PIMCO Managed Accounts Trust
Prospectus
May 1, 2024
Fixed Income SHares (FISH)
Fixed Income SHares: Series C (“FISH: Series C”)
FXICX
Fixed Income SHares: Series M (“FISH: Series M”)
FXIMX
Fixed Income SHares: Series R (“FISH: Series R”)
FXIRX
Fixed Income SHares: Series TE (“FISH: Series TE”)
FXIEX
Fixed Income SHares: Series LD (“FISH: Series LD”)
FXIDX
Neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.



Fixed Income SHares: Series C

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
The table below describes the fees and expenses you pay if you buy, hold and sell shares of the Portfolio. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below.
Shareholder Fees (fees paid directly from your investment):
None
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
FISH: Series C
Advisory Fees (1)
0.00 %
Other Expenses (2)
0.03 %
Total Annual Portfolio Operating Expenses
0.03 %
1
The Portfolio does not pay an advisory fee to Pacific Investment Management Company LLC (“PIMCO”) under the Investment Advisory Contract between PIMCO Managed Accounts Trust (the “Trust”) and PIMCO (the “Investment Advisory Contract”). However, the Portfolio is an integral part of “wrap-fee” programs, including those sponsored by investment advisers and broker- dealers unaffiliated with the Portfolio or PIMCO. Participants in these programs pay a “wrap” fee to the sponsor of the program. You should read carefully the wrap-fee brochure provided to you by the sponsor or your investment adviser. The brochure is required to include information about the fees charged to you by the sponsor and the fees paid by the sponsor to PIMCO and its affiliates. You pay no additional fees or expenses to purchase shares of the Portfolio.
2
“Other Expenses” include interest expense of 0.03%. Interest expense is borne by the Portfolio separately from the management fees paid to PIMCO. Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.00%.
Example. This Example is intended to help you compare the cost of investing in shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 in shares of the Portfolio for the time periods indicated, and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions.
 
1 Year
3 Years
5 Years
10 Years
FISH: Series C
$ 3
$ 10
$ 17
$ 39
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, can adversely affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 571 % of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by normally investing substantially all (and at least 80%) of its net assets (plus borrowings made for investment purposes) in a portfolio of U.S. and foreign fixed income instruments including (but not limited to): corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper; floating and variable rate debt instruments, inflation-indexed bonds issued by corporations; structured notes, including hybrid or “indexed” securities and event-linked bonds; loan participations and assignments; delayed funding loans and revolving credit facilities; bank certificates of deposit, fixed time deposits and bankers’ acceptances; repurchase agreements and reverse repurchase agreements; debt securities issued by states or local governments and their agencies, authorities and other instrumentalities; obligations of non-U.S. governments and their subdivisions, agencies and government sponsored enterprises; obligations of international agencies or supranational entities; obligations issued or guaranteed by the U.S. Government, its agencies and instrumentalities; mortgage-related and other asset-backed securities, such as mortgage pass-through securities, collateralized mortgage obligations, commercial mortgage-backed securities, mortgage dollar rolls, stripped mortgage-backed securities, collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities; and derivative instruments that have economic characteristics similar to the securities referenced above.
The Portfolio may invest up to 50% of its assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investor Services (“Moody’s”), or equivalently rated by Standard & Poor’s (“S&P”) or Fitch Ratings, Inc. (“Fitch”) or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. Subject to the limitations set forth in this prospectus, the Portfolio may invest in foreign (non-U.S.) currencies, securities denominated in foreign (non-U.S.) currencies, U.S. dollar denominated securities of foreign issuers, and securities and instruments of issuers that are economically tied to emerging market countries.
The Portfolio may invest up to 55% of its assets in securities issued or guaranteed by the U.S. Government, its agencies or instrumentalities. Certain of these securities issued by U.S. Government-sponsored entities may not be backed by the full faith and credit of the U.S. Government. Mortgage-related and other asset-backed securities issued or guaranteed by the U.S. Government, its agencies or instrumentalities are not subject to this limitation. The Portfolio may invest without limitation in mortgage-related and other asset-backed securities, including mortgage-related and other asset-backed securities issued or guaranteed by the U.S. Government, its agencies or instrumentalities.

PIMCO Managed Accounts Trust | Prospectus 1

Fixed Income SHares: Series C

The Portfolio may invest in instruments of any maturity. The average portfolio duration of the Portfolio is expected to vary and may range anywhere from relatively short (e.g., less than two years) to relatively long (e.g., more than ten years) based on PIMCO’s forecast for interest rates.
The Portfolio may invest without limit in derivative instruments, such as options, futures contracts or swap agreements, which may relate to fixed income securities, interest rates, currencies or currency exchange rates, commodities, real estate and other assets, and related indices. The Portfolio may lend its portfolio securities to brokers, dealers and other financial institutions to earn income. Although the Portfolio may invest in derivatives of any kind, it expects to invest in futures contracts, swaps and forward foreign currency contracts and to write (sell) put and call options on securities for hedging, risk management or other purposes, including for the purpose or having the effect of creating leverage. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest in contingent convertible securities. The “total return” sought by the Portfolio consists of income earned on its investments, plus capital appreciation, if any, generally arising from decreases in interest rates or improving credit fundamentals for a particular sector or security.
The Portfolio will not change its policy to, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income instruments unless the Portfolio provides shareholders with the notice required by Rule 35d-1 under the Investment Company Act of 1940, as it may be amended or interpreted by the Securities and Exchange Commission (the “SEC”) from time to time (the “1940 Act”).
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below:
Interest Rate Risk: the risk that fixed income securities will fluctuate in value because of a change in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, or the issuer or guarantor of collateral, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Foreign (Non-U.S.) Investment Risk: the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing
more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, political changes, diplomatic developments or the imposition of sanctions and other similar measures. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Mortgage-Related and Other Asset-Backed Securities Risk: the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk. The Portfolio may invest in any tranche or mortgage-related and other asset-backed securities, including junior and/or equity tranches (to the extent consistent with the other of the Portfolio's guidelines), which generally carry higher levels of the foregoing risks
Emerging Markets Risk: the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Focused Investment Risk: the risk that, to the extent that the Portfolio focuses its investments in a particular sector, it may be susceptible to loss due to adverse developments affecting that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to market developments, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region
Derivatives Risk: the risk of investing in derivative instruments (such as forwards, futures, swaps and structured securities) and other similar investments, including leverage, liquidity, interest rate, market, counterparty (including credit), operational, legal and management risks, and valuation complexity. Changes in the value of a derivative or other similar investment may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. Changes in the value of a derivative or other similar instrument may also create margin delivery or settlement payment obligations for the Portfolio. The Portfolio’s use of derivatives or other similar investments may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Non-centrally-cleared over-the-counter (“OTC”) derivatives or other similar investments are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for non-centrally-cleared OTC derivatives or other similar investments. The primary credit risk on derivatives or other similar investments that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker

2  Prospectus | PIMCO Managed Accounts Trust

Prospectus

or the clearinghouse. Changes in regulation relating to a registered fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives or other similar investments and/or adversely affect the value of derivatives or other similar investments and the Portfolio’s performance
Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio managers in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Currency Risk: the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, changes in financial condition or credit rating, financial leverage, reputation or reduced demand for the issuer’s goods or services
Turnover Risk: the risk that high levels of portfolio turnover may increase transaction costs and taxes and may lower investment performance
Municipal Securities Risk: the risk that investing in municipal securities subjects the Portfolio to certain risks, including variations in the quality of municipal securities, both within a particular classification and between classifications. The rates of return on municipal securities can depend on a variety of factors, including general money market conditions, the financial condition of the issuer, general conditions of the municipal bond market, the size of a particular offering, the maturity of the obligation and the rating of the issue
Inflation/Deflation Risk: the risk that the value of assets or income from a Portfolio's investments will be worth less in the future as inflation decreases the value of payments at future dates. As inflation increases, the real value of a Portfolio's investments could decline. Deflation risk is the risk that prices throughout the economy decline over time. Deflation may have an adverse effect on the creditworthiness of issuers and may make issuer default more likely, which may result in a decline in the value of a Portfolio's investments
Contingent Convertible Securities Risk: the risks of investing in contingent convertible securities, including the risk that interest payments will be cancelled by the issuer or a regulatory authority, the risk of ranking junior to other creditors in the event of a liquidation or other bankruptcy-related event as a result of holding subordinated debt, the risk of the Portfolio’s investment becoming further subordinated as a result of conversion from debt to equity, the risk that principal amount due can be written down to a lesser amount (including potentially to zero), and the general risks applicable to fixed income investments, including interest rate risk, credit risk, market risk and liquidity risk, any of which could result in losses to the Portfolio
LIBOR Transition Risk: the risk related to the discontinuation and replacement of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely or relied in some fashion upon LIBOR. Although the transition process away from LIBOR for most instruments has been completed, some LIBOR use is continuing and there are potential effects related to the transition away from LIBOR or the continued use of LIBOR on the Portfolio, or on certain instruments in which the Portfolio invests, which can be difficult to ascertain and could result in losses to the Portfolio
Collateralized Loan Obligations Risk: the risk that investing in collateralized loan obligations (“CLOs”) and other similarly structured investments exposes the Portfolio to heightened credit risk, interest rate risk, liquidity risk, market risk and prepayment and extension risk, as well as the risk of default on the underlying asset. In addition, investments in CLOs carry additional risks including, but not limited to: (i) the possibility that distributions from collateral securities will not be adequate to make interest or other payments; (ii) the quality of the collateral may decline in value or default; (iii) risks related to the capability of the servicer of the securitized assets; (iv) the risk that the Portfolio may invest in tranches of CLOs that are subordinate to other tranches; (v) the structure and complexity of the transaction and the legal documents may not be fully understood at the time of investment and could lead to disputes with the issuer or among investors regarding

May 1, 2024 | Prospectus 3

Fixed Income SHares: Series C

the characterization of proceeds or unexpected investment results; and (vi) the CLO's manager may perform poorly
Please see “Description of Principal Risks” for more information regarding the risks associated with investing in the Portfolio. An investment in the Portfolio is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual total returns compare with the returns of a broad-based securities market index. Absent any applicable fee waivers and/or expense limitations, performance would have been lower. The information in the bar chart and Average Annual Total Returns Table does not reflect payment of any applicable “wrap” fees by clients of “wrap-fee” programs that invest in the Portfolio to the program sponsors. The Portfolio’s past performance, before and after taxes, is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s benchmark is the Bloomberg U.S. Intermediate Credit Index. The Bloomberg U.S. Intermediate Credit Index is an unmanaged index of publicly issued U.S. corporate and specified non-U.S. debentures and secured notes with intermediate maturities ranging from 1 to less than 10 years. Securities must also meet specific liquidity and quality requirements. To qualify, bonds must be SEC-registered. It is not possible to invest directly in an index.
Calendar Year Total Returns
Best Quarter
December 31, 2023
7.51 %
Worst Quarter
June 30, 2022
- 7.81 %
Average Annual Total Returns (for periods ended 12/31/23)
 
1 Year
5 Years
10 Years
Fixed Income SHares: Series C - Before Taxes
8.34 %
1.64 %
2.01 %
Fixed Income SHares: Series C - After Taxes on
Distributions (1)
6.35 %
0.01 %
- 0.13 %
Fixed Income SHares: Series C - After Taxes on
Distributions and Sale of Portfolio Shares (1)
4.88 %
0.58 %
0.62 %
Bloomberg U.S. Intermediate Credit Index (reflects no
deductions for fees, expenses or taxes)
6.94 %
2.44 %
2.46 %
1
After-tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from tax returns shown. After-tax returns are not relevant to investors who hold their shares through tax advantaged arrangements such as 401(k) plans or individual retirement accounts. In some cases the return after taxes may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of Portfolio shares at the end of the measurement period.
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser and administrator for the Portfolio. The Portfolio is jointly and primarily managed by David Braun, Mike Cudzil and Vinayak Seshasayee. Mr. Braun is a Managing Director in PIMCO’s New York office and head of the U.S. financial institutions group and stable value portfolio management teams. Mr. Cudzil is a Managing Director in PIMCO’s Newport Beach office and Mr. Seshasayee is an Executive Vice President in PIMCO’s New York office. Mr. Braun has managed the Portfolio since May 2016 and Messrs. Cudzil and Seshasayee have managed the Portfolio since October 2022.
Other Important Information Regarding Portfolio Shares
For important information about purchase and sale of Portfolio shares and tax information, please turn to the “Summary of Other Important Information Regarding Portfolio Shares” section on page 21 of this prospectus.

4  Prospectus | PIMCO Managed Accounts Trust

Fixed Income SHares: Series M

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
The table below describes the fees and expenses you pay if you buy, hold and sell shares of the Portfolio. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below.
Shareholder Fees (fees paid directly from your investment):
None
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
FISH: Series M
Advisory Fees (1)
0.00 %
Other Expenses (2)
0.04 %
Total Annual Portfolio Operating Expenses
0.04 %
1
The Portfolio does not pay an advisory fee to Pacific Investment Management Company LLC (“PIMCO”) under the Investment Advisory Contract between PIMCO Managed Accounts Trust (the “Trust”) and PIMCO (the “Investment Advisory Contract”). However, the Portfolio is an integral part of “wrap-fee” programs, including those sponsored by investment advisers and broker- dealers unaffiliated with the Portfolio or PIMCO. Participants in these programs pay a “wrap” fee to the sponsor of the program. You should read carefully the wrap-fee brochure provided to you by the sponsor or your investment adviser. The brochure is required to include information about the fees charged to you by the sponsor and the fees paid by the sponsor to PIMCO and its affiliates. You pay no additional fees or expenses to purchase shares of the Portfolio.
2
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to PIMCO. Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.00%.
Example. This Example is intended to help you compare the cost of investing in shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 in shares of the Portfolio for the time periods indicated, and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions.
 
1 Year
3 Years
5 Years
10 Years
FISH: Series M
$ 4
$ 13
$ 23
$ 51
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, can adversely affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 569 % of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by normally investing at least 80% of its net assets (plus borrowings made for investment purposes) in a portfolio of U.S. and foreign fixed income instruments of varying maturities including (but not limited to): mortgage-and other asset-backed securities, such as mortgage pass-through securities, collateralized mortgage obligations, commercial mortgage-backed securities, mortgage dollar rolls, stripped mortgage-backed securities, collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property; obligations issued or guaranteed by the U.S. Government, its agencies and instrumentalities; corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper; floating and variable rate debt instruments; structured notes, including hybrid or “indexed” securities and event-linked bonds, loan participations and assignments, delayed funding loans and revolving credit facilities, debt securities issued by states or local governments and their agencies, authorities and other instrumentalities; bank certificates of deposit and fixed time deposits and bankers’ acceptances; repurchase agreements and reverse repurchase agreements; and derivative instruments that have economic characteristics similar to the securities referenced above.
The Portfolio may invest in instruments of any maturity. The average portfolio duration of the Portfolio is expected to vary and may range anywhere from relatively short (e.g., less than two years) to relatively long (e.g., more than ten years) based on PIMCO’s forecast for interest rates.
Subject to the limitations set forth in this prospectus, the Portfolio may invest in foreign (non-U.S.) currencies, securities denominated in foreign (non- U.S.) currencies, U.S. dollar denominated securities of foreign issuers, and securities and instruments of issuers that are economically tied to emerging market countries.
The Portfolio may invest without limit in securities issued or guaranteed by the U.S. Government, its agencies or instrumentalities. Certain of these securities issued by U.S. Government-sponsored entities may not be backed by the full faith and credit of the U.S. Government.
The Portfolio may invest up to 50% of its assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investor Services (“Moody’s”), or equivalently rated by Standard & Poor’s (“S&P”) or Fitch Ratings, Inc. (“Fitch”) or, if unrated, determined by PIMCO to be of comparable quality (except that, within such 50% limitation, the Portfolio may invest in mortgage-related securities rated below B). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest without limit in derivative instruments, such as options, futures contracts or swap agreements, which may relate to fixed income securities, interest rates, currencies or currency exchange rates, commodities, real estate and other assets, and related indices.

PIMCO Managed Accounts Trust | Prospectus 5

Fixed Income SHares: Series M

The Portfolio may invest without limit in mortgage- or asset-backed securities, including mortgage-related and other asset-backed securities issued or guaranteed by the U.S. Government, its agencies or instrumentalities. Although the Portfolio may invest in derivatives of any kind, it expects to invest in futures contracts, swaps and forward foreign currency contracts and to write (sell) put and call options on securities for hedging, risk management or other purposes, including for the purpose or having the effect of creating leverage. The Portfolio may lend its portfolio securities to brokers, dealers and other financial institutions to earn income. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest in contingent convertible securities. The “total return” sought by the Portfolio consists of income earned on its investments, plus capital appreciation, if any, generally arising from decreases in interest rates or improving credit fundamentals for a particular sector or security.
The Portfolio will not change its policy to, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in a portfolio of U.S. and foreign fixed income instruments of varying maturities unless the Portfolio provides shareholders with the notice required by Rule 35d-1 under the Investment Company Act of 1940, as it may be amended or interpreted by the Securities and Exchange Commission (the “SEC”) from time to time (the “1940 Act”).
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below:
Mortgage-Related and Other Asset-Backed Securities Risk: the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk. The Portfolio may invest in any tranche or mortgage-related and other asset-backed securities, including junior and/or equity tranches (to the extent consistent with the other of the Portfolio's guidelines), which generally carry higher levels of the foregoing risks
Interest Rate Risk: the risk that fixed income securities will fluctuate in value because of a change in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, or the issuer or guarantor of collateral, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Focused Investment Risk: the risk that, to the extent that the Portfolio focuses its investments in a particular sector, it may be susceptible to loss due to adverse developments affecting that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to market developments, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region
Foreign (Non-U.S.) Investment Risk: the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, political changes, diplomatic developments or the imposition of sanctions and other similar measures. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Derivatives Risk: the risk of investing in derivative instruments (such as forwards, futures, swaps and structured securities) and other similar investments, including leverage, liquidity, interest rate, market, counterparty (including credit), operational, legal and management risks, and valuation complexity. Changes in the value of a derivative or other similar investment may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. Changes in the value of a derivative or other similar instrument may also create margin delivery or settlement payment obligations for the Portfolio. The Portfolio’s use of derivatives or other similar investments may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Non-centrally-cleared over-the-counter (“OTC”) derivatives or other similar investments are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for non-centrally-cleared OTC derivatives or other similar investments. The primary credit risk on derivatives or other similar investments that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a registered fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives or other similar investments and/or adversely affect the value of derivatives or other similar investments and the Portfolio’s performance
Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid

6  Prospectus | PIMCO Managed Accounts Trust

Prospectus

investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio managers in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Emerging Markets Risk: the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, changes in financial condition or credit rating, financial leverage, reputation or reduced demand for the issuer’s goods or services
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Turnover Risk: the risk that high levels of portfolio turnover may increase transaction costs and taxes and may lower investment performance
Currency Risk: the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Municipal Securities Risk: the risk that investing in municipal securities subjects the Portfolio to certain risks, including variations in the quality of municipal securities, both within a particular classification and between classifications. The rates of return on municipal securities can depend on a variety of factors, including general money market conditions, the financial condition of the issuer, general conditions of
the municipal bond market, the size of a particular offering, the maturity of the obligation and the rating of the issue
Inflation/Deflation Risk: the risk that the value of assets or income from a Portfolio's investments will be worth less in the future as inflation decreases the value of payments at future dates. As inflation increases, the real value of a Portfolio's investments could decline. Deflation risk is the risk that prices throughout the economy decline over time. Deflation may have an adverse effect on the creditworthiness of issuers and may make issuer default more likely, which may result in a decline in the value of a Portfolio's investments
Contingent Convertible Securities Risk: the risks of investing in contingent convertible securities, including the risk that interest payments will be cancelled by the issuer or a regulatory authority, the risk of ranking junior to other creditors in the event of a liquidation or other bankruptcy-related event as a result of holding subordinated debt, the risk of the Portfolio’s investment becoming further subordinated as a result of conversion from debt to equity, the risk that principal amount due can be written down to a lesser amount (including potentially to zero), and the general risks applicable to fixed income investments, including interest rate risk, credit risk, market risk and liquidity risk, any of which could result in losses to the Portfolio
LIBOR Transition Risk: the risk related to the discontinuation and replacement of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely or relied in some fashion upon LIBOR. Although the transition process away from LIBOR for most instruments has been completed, some LIBOR use is continuing and there are potential effects related to the transition away from LIBOR or the continued use of LIBOR on the Portfolio, or on certain instruments in which the Portfolio invests, which can be difficult to ascertain and could result in losses to the Portfolio
Collateralized Loan Obligations Risk: the risk that investing in collateralized loan obligations (“CLOs”) and other similarly structured investments exposes the Portfolio to heightened credit risk, interest rate risk, liquidity risk, market risk and prepayment and extension risk, as well as the risk of default on the underlying asset. In addition, investments in CLOs carry additional risks including, but not limited to: (i) the possibility that distributions from collateral securities will not be adequate to make interest or other payments; (ii) the quality of the collateral may decline in value or default; (iii) risks related to the capability of the servicer of the securitized assets; (iv) the risk that the Portfolio may invest in tranches of CLOs that are subordinate to other tranches; (v) the structure and complexity of the transaction and the legal documents may not be fully understood at the time of investment and could lead to disputes with the issuer or among investors regarding the characterization of proceeds or unexpected investment results; and (vi) the CLO's manager may perform poorly
Please see “Description of Principal Risks” for more information regarding the risks associated with investing in the Portfolio. An investment in the Portfolio is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

May 1, 2024 | Prospectus 7

Fixed Income SHares: Series M

Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual total returns compare with the returns of a broad-based securities market index. Absent any applicable fee waivers and/or expense limitations, performance would have been lower. The information in the bar chart and Average Annual Total Returns Table does not reflect payment of any applicable “wrap” fees by clients of “wrap-fee” programs that invest in the Portfolio to the program sponsors. The Portfolio’s past performance, before and after taxes, is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s benchmark is the Bloomberg U.S. MBS Fixed-Rate Index. The Bloomberg U.S. MBS Fixed-Rate Index is an unmanaged index of mortgage-backed pass-through securities and hybrid ARM pools of Ginnie Mae (GNMA), Fannie Mae (FNMA), and Freddie Mac (FHLMC). The MBS Index is formed by grouping individual fixed rate MBS pools into generic aggregates. It is not possible to invest directly in an index.
Calendar Year Total Returns
Best Quarter
June 30, 2020
7.93 %
Worst Quarter
June 30, 2022
- 6.26 %
Average Annual Total Returns (for periods ended 12/31/23)
 
1 Year
5 Years
10 Years
Fixed Income SHares: Series M - Before Taxes
9.12 %
2.17 %
3.65 %
Fixed Income SHares: Series M - After Taxes on
Distributions (1)
6.63 %
- 0.06 %
1.33 %
Fixed Income SHares: Series M - After Taxes on
Distributions and Sale of Portfolio Shares (1)
5.32 %
0.74 %
1.83 %
Bloomberg U.S. MBS Fixed-Rate Index (reflects no
deductions for fees, expenses or taxes)
5.05 %
0.25 %
1.39 %
1
After-tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from tax returns shown. After-tax returns are not relevant to investors who hold their shares through tax advantaged arrangements such as 401(k) plans or individual retirement accounts. In some cases the return after taxes may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of Portfolio shares at the end of the measurement period.
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser and administrator for the Portfolio. The Portfolio is jointly and primarily managed by David Braun, Mike Cudzil and Vinayak Seshasayee. Mr. Braun is a Managing Director in PIMCO’s New York office and head of the U.S. financial institutions group and stable value portfolio management teams. Mr. Cudzil is a Managing Director in PIMCO’s Newport Beach office and Mr. Seshasayee is an Executive Vice President in PIMCO’s New York office. Mr. Braun has managed the Portfolio since May 2016 and Messrs. Cudzil and Seshasayee have managed the Portfolio since October 2022.
Other Important Information Regarding Portfolio Shares
For important information about purchase and sale of Portfolio shares and tax information, please turn to the “Summary of Other Important Information Regarding Portfolio Shares” section on page 21 of this prospectus.

8  Prospectus | PIMCO Managed Accounts Trust

Fixed Income SHares: Series R

Investment Objective
The Portfolio seeks maximum real return, consistent with preservation of real capital and prudent investment management.
Fees and Expenses of the Portfolio
The table below describes the fees and expenses you pay if you buy, hold and sell shares of the Portfolio. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below.
Shareholder Fees (fees paid directly from your investment):
None
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
FISH: Series R
Advisory Fees (1)
0.00 %
Other Expenses (2)
3.31 %
Total Annual Portfolio Operating Expenses
3.31 %
1
The Portfolio does not pay an advisory fee to Pacific Investment Management Company LLC (“PIMCO”) under the Investment Advisory Contract between PIMCO Managed Accounts Trust (the “Trust”) and PIMCO (the “Investment Advisory Contract”). However, the Portfolio is an integral part of “wrap-fee” programs, including those sponsored by investment advisers and broker- dealers unaffiliated with the Portfolio or PIMCO. Participants in these programs pay a “wrap” fee to the sponsor of the program. You should read carefully the wrap-fee brochure provided to you by the sponsor or your investment adviser. The brochure is required to include information about the fees charged to you by the sponsor and the fees paid by the sponsor to PIMCO and its affiliates. You pay no additional fees or expenses to purchase shares of the Portfolio.
2
“Other Expenses” include interest expense of 3.31%. Interest expense is borne by the Portfolio separately from the management fees paid to PIMCO. Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.00%.
Example. This Example is intended to help you compare the cost of investing in shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 in shares of the Portfolio for the time periods indicated, and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions.
 
1 Year
3 Years
5 Years
10 Years
FISH: Series R
$ 334
$ 1,018
$ 1,726
$ 3,604
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, can adversely affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 223 % of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by normally investing at least 80% of its net assets (plus borrowings made for investment purposes) in a portfolio of U.S. and foreign fixed income instruments including (but not limited to): inflation-indexed bonds issued by both U.S. and non-U.S. governments and corporations, including Treasury Inflation Protected Securities (“TIPS”); corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper; obligations issued or guaranteed by the U.S. Government, its agencies and instrumentalities; obligations of non-U.S. governments or their subdivisions, agencies and government sponsored enterprises; obligations of international agencies or supranational entities; debt securities issued by states or local governments and their agencies, authorities and other instrumentalities; mortgage-related and other asset-backed securities including collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities; floating and variable rate debt instruments; structured notes, including hybrid or “indexed” securities and event-linked bonds; loan participations and assignments; delayed funding loans and revolving credit facilities; bank certificates of deposit, fixed time deposits and bankers’ acceptances; repurchase agreements and reverse repurchase agreements; and derivative instruments that have economic characteristics similar to the securities referenced above.
In pursuing its investment objective of real return, the Portfolio ordinarily expects to invest a substantial portion of its assets in inflation-indexed bonds of various maturities issued by U.S. and non-U.S. governments, their agencies or instrumentalities, and corporations. Certain securities issued by U.S. Government-sponsored entities may not be backed by the full faith and credit of the U.S. Government. “Real return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. Inflation-indexed bonds are fixed income securities that are structured to provide protection against inflation. The value of the bond’s principal or the interest income paid on the bond is adjusted to track changes in an official inflation measure. The U.S. Treasury uses the non-seasonally adjusted Consumer Price Index for All Urban Consumers as the inflation measure. Inflation-indexed bonds issued by a foreign government are generally adjusted to reflect a comparable inflation index, calculated by that government.
The Portfolio invests primarily in investment grade securities, but may invest up to 20% of its assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investor Services (“Moody’s”), or equivalently rated by Standard & Poor’s (“S&P”) or Fitch Ratings, Inc. (“Fitch”) or, if unrated, determined by PIMCO to be of comparable quality (except that within such 20% limitation, the Portfolio may invest in mortgage-related securities rated below B). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest, subject to applicable law, without limit in foreign (non-U.S.) currencies, securities denominated in foreign (non-U.S.) currencies, and U.S. dollar denominated securities of foreign issuers. The Portfolio may

PIMCO Managed Accounts Trust | Prospectus 9

Fixed Income SHares: Series R

invest without limit in investment grade sovereign debt denominated in the relevant country’s local currency with less than 1 year remaining to maturity (“short-term investment grade sovereign debt”), including short-term investment grade sovereign debt issued by emerging market issuers. The Portfolio may invest up to 20% of its total assets in securities of issuers economically tied to “emerging market” countries other than investments in short-term investment grade sovereign debt issued by emerging market issuers, where as noted above there is no limit.
The Portfolio may invest in instruments of any maturity. The average portfolio duration of the Portfolio is expected to vary and may range anywhere from relatively short (e.g., less than two years) to relatively long (e.g., more than ten years) based on PIMCO’s forecast for interest rates.
The Portfolio may invest without limit in derivative instruments, such as options, futures contracts or swap agreements, which may relate to fixed income securities, interest rates, currencies or currency exchange rates, commodities, real estate and other assets, and related indices. Although the Portfolio may invest in derivatives of any kind, it expects to invest in futures contracts, swaps and forward foreign currency contracts and to write (sell) put and call options on securities for hedging, risk management or other purposes, including for the purpose or having the effect of creating leverage. The Portfolio may lend its securities to brokers, dealers and other financial institutions to earn income. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls).
The Portfolio will not change its policy to, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in U.S. and foreign fixed income instruments unless the Portfolio provides shareholders with the notice required by Rule 35d-1 under the Investment Company Act of 1940, as it may be amended or interpreted by the Securities and Exchange Commission (the “SEC”) from time to time (the “1940 Act”).
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below:
Interest Rate Risk: the risk that fixed income securities will fluctuate in value because of a change in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, or the issuer or guarantor of collateral, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Foreign (Non-U.S.) Investment Risk: the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, political changes, diplomatic developments or the imposition of sanctions and other similar measures. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Mortgage-Related and Other Asset-Backed Securities Risk: the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk. The Portfolio may invest in any tranche or mortgage-related and other asset-backed securities, including junior and/or equity tranches (to the extent consistent with the other of the Portfolio's guidelines), which generally carry higher levels of the foregoing risks
Emerging Markets Risk: the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Focused Investment Risk: the risk that, to the extent that the Portfolio focuses its investments in a particular sector, it may be susceptible to loss due to adverse developments affecting that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to market developments, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region
Derivatives Risk: the risk of investing in derivative instruments (such as forwards, futures, swaps and structured securities) and other similar investments, including leverage, liquidity, interest rate, market, counterparty (including credit), operational, legal and management risks, and valuation complexity. Changes in the value of a derivative or other similar investment may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. Changes in the value of a derivative or other similar instrument may also create margin delivery or settlement payment obligations for the Portfolio. The Portfolio’s use of derivatives or other similar investments may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Non-centrally-cleared over-the-counter (“OTC”) derivatives or other similar investments are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the

10  Prospectus | PIMCO Managed Accounts Trust

Prospectus

protections afforded to centrally-cleared derivative transactions might not be available for non-centrally-cleared OTC derivatives or other similar investments. The primary credit risk on derivatives or other similar investments that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a registered fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives or other similar investments and/or adversely affect the value of derivatives or other similar investments and the Portfolio’s performance
Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio managers in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Currency Risk: the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance,
changes in financial condition or credit rating, financial leverage, reputation or reduced demand for the issuer’s goods or services
Turnover Risk: the risk that high levels of portfolio turnover may increase transaction costs and taxes and may lower investment performance
Municipal Securities Risk: the risk that investing in municipal securities subjects the Portfolio to certain risks, including variations in the quality of municipal securities, both within a particular classification and between classifications. The rates of return on municipal securities can depend on a variety of factors, including general money market conditions, the financial condition of the issuer, general conditions of the municipal bond market, the size of a particular offering, the maturity of the obligation and the rating of the issue
Inflation/Deflation Risk: the risk that the value of assets or income from a Portfolio's investments will be worth less in the future as inflation decreases the value of payments at future dates. As inflation increases, the real value of a Portfolio's investments could decline. Deflation risk is the risk that prices throughout the economy decline over time. Deflation may have an adverse effect on the creditworthiness of issuers and may make issuer default more likely, which may result in a decline in the value of a Portfolio's investments
Sovereign Debt Risk: the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Please see “Description of Principal Risks” for more information regarding the risks associated with investing in the Portfolio. An investment in the Portfolio is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual total returns compare with the returns of a broad-based securities market index. Absent any applicable fee waivers and/or expense limitations, performance would have been lower. The information in the bar chart and Average Annual Total Returns Table does not reflect payment of any applicable “wrap” fees by clients of “wrap-fee” programs that invest in the Portfolio to the program sponsors. The Portfolio’s past performance, before and after taxes, is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s benchmark is the Bloomberg U.S. TIPS Index. The Bloomberg U.S. TIPS Index is an unmanaged index comprised of all U.S. Treasury Inflation Protected Securities rated investment grade (Baa3

May 1, 2024 | Prospectus 11

Fixed Income SHares: Series R

or better), have at least one year to final maturity, and at least $500 million par amount outstanding. It is not possible to directly invest in an index.
Calendar Year Total Returns
Best Quarter
June 30, 2020
7.16 %
Worst Quarter
June 30, 2022
- 9.44 %
Average Annual Total Returns (for periods ended 12/31/23)
 
1 Year
5 Years
10 Years
Fixed Income SHares: Series R - Before Taxes
3.18 %
3.45 %
2.52 %
Fixed Income SHares: Series R - After Taxes on
Distributions (1)
2.19 %
1.36 %
0.52 %
Fixed Income SHares: Series R - After Taxes on
Distributions and Sale of Portfolio Shares (1)
1.87 %
1.82 %
1.07 %
Bloomberg U.S. TIPS Index (reflects no deductions for
fees, expenses or taxes)
3.90 %
3.15 %
2.42 %
1
After-tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from tax returns shown. After-tax returns are not relevant to investors who hold their shares through tax advantaged arrangements such as 401(k) plans or individual retirement accounts. In some cases the return after taxes may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of Portfolio shares at the end of the measurement period.
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser and administrator for the Portfolio. The Portfolio is jointly and primarily managed by Steve Rodosky and Daniel He. Mr. Rodosky is a Managing Director and portfolio manager in PIMCO’s Newport Beach office. Mr. He is an Executive Vice President and portfolio manager in PIMCO’s Newport Beach office. Mr. Rodosky has managed the Portfolio since January 2019. Mr. He has managed the Portfolio since December 2019.
Other Important Information Regarding Portfolio Shares
For important information about purchase and sale of Portfolio shares and tax information, please turn to the “Summary of Other Important Information Regarding Portfolio Shares” section on page 21 of this prospectus.

12  Prospectus | PIMCO Managed Accounts Trust

Fixed Income SHares: Series TE

Investment Objectives
The Portfolio seeks high current income exempt from U.S. federal income tax consistent with prudent investment management. Total return/capital appreciation is a secondary objective.
Fees and Expenses of the Portfolio
The table below describes the fees and expenses you pay if you buy, hold and sell shares of the Portfolio. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below.
Shareholder Fees (fees paid directly from your investment):
None
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
FISH: Series TE
Advisory Fees (1)
0.00 %
Other Expenses (2)
0.06 %
Total Annual Portfolio Operating Expenses
0.06 %
1
The Portfolio does not pay an advisory fee to Pacific Investment Management Company LLC (“PIMCO”) under the Investment Advisory Contract between PIMCO Managed Accounts Trust (the “Trust”) and PIMCO (the “Investment Advisory Contract”). However, the Portfolio is an integral part of “wrap-fee” programs, including those sponsored by investment advisers and broker- dealers unaffiliated with the Portfolio or PIMCO. Participants in these programs pay a “wrap” fee to the sponsor of the program. You should read carefully the wrap-fee brochure provided to you by the sponsor or your investment adviser. The brochure is required to include information about the fees charged to you by the sponsor and the fees paid by the sponsor to PIMCO and its affiliates. You pay no additional fees or expenses to purchase shares of the Portfolio.
2
“Other Expenses” include interest expense of 0.06%. Interest expense is borne by the Portfolio separately from the management fees paid to PIMCO. Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.00%.
Example. This Example is intended to help you compare the cost of investing in shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 in shares of the Portfolio for the time periods indicated, and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions.
 
1 Year
3 Years
5 Years
10 Years
FISH: Series TE
$ 6
$ 19
$ 34
$ 77
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example
table, can adversely affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 56 % of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its objective by investing in municipal securities to generate income exempt from U.S. federal income tax. The Portfolio normally invests at least 80% of its net assets (plus borrowings made for investment purposes) in a portfolio of U.S. fixed income instruments comprised of debt securities whose interest is, in the opinion of bond counsel for the issuer at the time of issuance, exempt from federal income tax ( i.e. , excluded from gross income for federal income tax purposes but not necessarily exempt from the federal alternative minimum tax (“AMT”)) (the “80% Tax Exempt Policy”), including (but not limited to):
municipal debt securities issued by states and their agencies, authorities and other instrumentalities which are exempt from federal income tax;
municipal debt securities issued by local governments and their agencies, authorities and other instrumentalities which are exempt from federal income tax; and
tax-exempt structured notes, which may contain embedded derivatives.
The Portfolio may invest without limit in bonds whose interest is a tax-preference item for purposes of the federal AMT.
The Portfolio may invest in instruments of any maturity. The average portfolio duration of the Portfolio is expected to vary and may range anywhere from relatively short ( e.g. , less than two years) to relatively long (e.g., more than ten years) based on PIMCO’s forecast for interest rates.
The Portfolio may invest without limit in U.S. dollar denominated securities. The Portfolio may invest without limit in U.S. Government securities, money market instruments and/or “private activity” bonds. Distributions derived from “private activity” bonds may be subject to the federal AMT. The Portfolio may invest more than 25% of its total assets in bonds of issuers in either California or New York, or both. To the extent that the Portfolio concentrates its investments in California or New York, it will be particularly subject to California or New York state-specific risks, as applicable.
The Portfolio may invest up to 80% of its total assets in high yield securities (“junk bonds”) rated below Baa3 by Moody’s Investor Services (“Moody’s”), or equivalently rated by Standard & Poor’s (“S&P”) or Fitch Ratings, Inc. (“Fitch”) or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security.
Subject to the 80% Tax Exempt Policy noted above, the Portfolio may invest the remainder of its assets in fixed income securities that generate income that is not exempt from federal income tax (for example, Build America Bonds).

PIMCO Managed Accounts Trust | Prospectus 13

Fixed Income SHares: Series TE

The Portfolio may invest in derivative instruments, such as options, futures contracts or swap agreements, which may relate to fixed income securities, interest rates, currencies or currency exchange rates, commodities, real estate and other assets, and related indices. Although the Portfolio did not invest significantly in derivative instruments as of the most recent fiscal year end, it may do so at any time. The Portfolio may lend its portfolio securities to brokers, dealers and other financial institutions to earn income. The Portfolio may also invest in securities issued by entities, such as trusts, whose underlying assets are municipal bonds, including, without limitation, inverse floating rate debt securities (“inverse floaters”). The Portfolio may seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls).
The Portfolio will not change the 80% Tax Exempt Policy unless the Portfolio provides shareholders with the notice required by Rule 35d-1 under the Investment Company Act of 1940, as it may be amended or interpreted by the Securities and Exchange Commission (the “SEC”) from time to time (the “1940 Act”).
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below:
Small Portfolio Risk: the risk that a smaller portfolio may not achieve investment or trading efficiencies. Additionally, a smaller portfolio may be more adversely affected by large purchases or redemptions of portfolio shares
Municipal Securities Risk: the risk that investing in municipal securities subjects the Portfolio to certain risks, including variations in the quality of municipal securities, both within a particular classification and between classifications. The rates of return on municipal securities can depend on a variety of factors, including general money market conditions, the financial condition of the issuer, general conditions of the municipal bond market, the size of a particular offering, the maturity of the obligation and the rating of the issue
Municipal Project-Specific Risk: the risk that the Portfolio may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation and utilities), industrial development bonds, or in bonds from issuers in a single state
Municipal Bond Market Risk: the risk that the Portfolio may be adversely affected due to factors such as limited amount of public information available regarding the municipal bonds held in the Portfolio as compared to that for corporate equities or bonds, legislative changes and local and business developments, general conditions of the municipal bond market, the size of the particular offering, the rating of the issue and the maturity of the obligation
Interest Rate Risk: the risk that fixed income securities will fluctuate in value because of a change in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, or the issuer or guarantor of collateral, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Focused Investment Risk: the risk that, to the extent that the Portfolio focuses its investments in a particular sector, it may be susceptible to loss due to adverse developments affecting that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to market developments, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region
Derivatives Risk: the risk of investing in derivative instruments (such as forwards, futures, swaps and structured securities) and other similar investments, including leverage, liquidity, interest rate, market, counterparty (including credit), operational, legal and management risks, and valuation complexity. Changes in the value of a derivative or other similar investment may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. Changes in the value of a derivative or other similar instrument may also create margin delivery or settlement payment obligations for the Portfolio. The Portfolio’s use of derivatives or other similar investments may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Non-centrally-cleared over-the-counter (“OTC”) derivatives or other similar investments are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for non-centrally-cleared OTC derivatives or other similar investments. The primary credit risk on derivatives or other similar investments that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a registered fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives or other similar investments and/or adversely affect the value of derivatives or other similar investments and the Portfolio’s performance

14  Prospectus | PIMCO Managed Accounts Trust

Prospectus

Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio managers in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, changes in financial condition or credit rating, financial leverage, reputation or reduced demand for the issuer’s goods or services
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
California State-Specific Risk: the risk that the Portfolio, to the extent it concentrates its investments in California municipal bonds, may be affected significantly by economic, regulatory or political developments affecting the ability of California issuers to pay interest or repay principal
New York State-Specific Risk: the risk that the Portfolio, to the extent it concentrates its investments in New York municipal bonds, may be affected significantly by economic, regulatory or political developments affecting the ability of New York issuers to pay interest or repay principal
Puerto Rico-Specific Risk: the risk that by investing in Municipal Bonds issued by Puerto Rico or its instrumentalities, the Portfolio may be affected by certain developments, such as political, economic, environmental, social, regulatory or debt restructuring developments,
that impact the ability or obligation of Puerto Rico municipal issuers to pay interest or repay principal
AMT Bonds Risk: the risk that “AMT Bonds,” which are municipal securities that pay interest that is taxable under the federal alternative minimum tax applicable to noncorporate taxpayers, may expose the Portfolio to certain risks in addition to those typically associated with municipal bonds. Interest or principal on AMT Bonds paid out of current or anticipated revenues from a specific project or specific asset may be adversely impacted by declines in revenue from the project or asset. Declines in general business activity could also affect the economic viability of facilities that are the sole source of revenue to support AMT Bonds. In this regard, AMT Bonds may entail greater risks than general obligation municipal bonds. For shareholders subject to the federal alternative minimum tax, a portion of the Portfolio’s distributions may not be exempt from gross federal income, which may give rise to alternative minimum tax liability
Inflation/Deflation Risk: the risk that the value of assets or income from a Portfolio's investments will be worth less in the future as inflation decreases the value of payments at future dates. As inflation increases, the real value of a Portfolio's investments could decline. Deflation risk is the risk that prices throughout the economy decline over time. Deflation may have an adverse effect on the creditworthiness of issuers and may make issuer default more likely, which may result in a decline in the value of a Portfolio's investments
Please see “Description of Principal Risks” for more information regarding the risks associated with investing in the Portfolio. An investment in the Portfolio is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual total returns compare with the returns of a broad-based securities market index. Absent any applicable fee waivers and/or expense limitations, performance would have been lower. The information in the bar chart and Average Annual Total Returns Table does not reflect payment of any applicable “wrap” fees by clients of “wrap-fee” programs that invest in the Portfolio to the program sponsors. The Portfolio’s past performance, before and after taxes, is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s benchmark is the Bloomberg 1-Year Municipal Bond Index. The Bloomberg 1-Year Municipal Bond Index is the 1 Year (1-2) component of the Bloomberg Municipal Bond Index. The Bloomberg Municipal Bond Index is a rules-based, market-value-weighted index engineered for the long term tax-exempt bond market. To be included in the Bloomberg Municipal Bond Index, bonds must be rated investment-grade (Baa3/BBB- or higher) by at least two of the following

May 1, 2024 | Prospectus 15

Fixed Income SHares: Series TE

ratings agencies: Moody’s, S&P and Fitch. If only two of the three agencies rate the security, the lower rating is used to determine index eligibility. If only one of the three agencies rates a security, the rating must be investment-grade. They must have an outstanding par value of at least $7 million and be issued as part of a transaction of at least $75 million. The bonds must be fixed rate, have a dated-date after December 31, 1990, and must be at least one year from their maturity date. Remarketed issues, taxable municipal bonds, bonds with floating rates, and derivatives, are excluded from the benchmark. It is not possible to invest directly in an index.
Calendar Year Total Returns
Best Quarter
December 31, 2023
7.77 %
Worst Quarter
March 31, 2022
- 5.91 %
Average Annual Total Returns (for periods ended 12/31/23)
 
1 Year
5 Years
10 Years
Fixed Income SHares: Series TE - Before Taxes
9.74 %
3.43 %
3.74 %
Fixed Income SHares: Series TE - After Taxes on
Distributions (1)
9.29 %
3.30 %
3.51 %
Fixed Income SHares: Series TE - After Taxes on
Distributions and Sale of Portfolio Shares (1)
7.38 %
3.44 %
3.51 %
Bloomberg 1-Year Municipal Bond Index (reflects no
deductions for fees, expenses or taxes)
3.39 %
1.34 %
1.09 %
1
After-tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from tax returns shown. After-tax returns are not relevant to investors who hold their shares through tax advantaged arrangements such as 401(k) plans or individual retirement accounts. In some cases the return after taxes may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of Portfolio shares at the end of the measurement period.
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser and administrator for the Portfolio. The Portfolio is jointly and primarily managed by David Hammer and Kyle Christine. Mr. Hammer is a Managing Director and head of municipal bond portfolio management in PIMCO’s Newport Beach office. Mr. Christine is a Senior Vice President and municipal bond portfolio manager in PIMCO’s Newport Beach office. Mr. Hammer has managed the Portfolio since August 2015. Mr. Christine has managed the Portfolio since April 2023.
Other Important Information Regarding Portfolio Shares
For important information about purchase and sale of Portfolio shares and tax information, please turn to the “Summary of Other Important Information Regarding Portfolio Shares” section on page 21 of this prospectus.

16  Prospectus | PIMCO Managed Accounts Trust

Fixed Income SHares: Series LD

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
The table below describes the fees and expenses you pay if you buy, hold and sell shares of the Portfolio. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below.
Shareholder Fees (fees paid directly from your investment):
None
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
FISH: Series LD
Advisory Fees (1)
0.00 %
Other Expenses (2)
2.31 %
Total Annual Portfolio Operating Expenses
2.31 %
1
The Portfolio does not pay an advisory fee to Pacific Investment Management Company LLC (“PIMCO”) under the Investment Advisory Contract between PIMCO Managed Accounts Trust (the “Trust”) and PIMCO (the “Investment Advisory Contract”). However, the Portfolio is an integral part of “wrap-fee” programs, including those sponsored by investment advisers and broker- dealers unaffiliated with the Portfolio or PIMCO. Participants in these programs pay a “wrap” fee to the sponsor of the program. You should read carefully the wrap-fee brochure provided to you by the sponsor or your investment adviser. The brochure is required to include information about the fees charged to you by the sponsor and the fees paid by the sponsor to PIMCO and its affiliates. You pay no additional fees or expenses to purchase shares of the Portfolio.
2
“Other Expenses” include interest expense of 2.31%. Interest expense is borne by the Portfolio separately from the management fees paid to PIMCO. Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.00%.
Example. This Example is intended to help you compare the cost of investing in shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 in shares of the Portfolio for the time periods indicated, and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions.
 
1 Year
3 Years
5 Years
10 Years
FISH: Series LD
$ 234
$ 721
$ 1,235
$ 2,646
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, can adversely affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 192 % of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by normally investing at least 80% of its net assets (plus borrowings made for investment purposes) in a diversified portfolio of U.S. and foreign fixed income securities of varying maturities, including (but not limited to): obligations issued or guaranteed by the U.S. Government, its agencies and instrumentalities; corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper; mortgage-related and other asset-backed securities including collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities; inflation-indexed bonds issued by both U.S. and non-U.S. governments and corporations, including Treasury Inflation Protected Securities (“TIPS”); structured notes, including hybrid or “indexed” securities and event-linked bonds; bank capital and trust preferred securities; loan participations and assignments; delayed funding loans and revolving credit facilities; bank certificates of deposit, fixed time deposits and bankers’ acceptances; repurchase agreements and reverse repurchase agreements; debt securities issued by states or local governments and their agencies, authorities and other instrumentalities; obligations of non-U.S. governments and their subdivisions, agencies and government sponsored enterprises; obligations of international agencies or supranational entities; floating and variable rate debt instruments; and derivative instruments that have economic characteristics similar to the securities referenced above.
The average duration of the Portfolio will normally be between zero and five years; however, the duration of the Portfolio will vary based on PIMCO’s forecast for interest rates. The Portfolio’s average duration may vary significantly from time to time, and there is no assurance that the Portfolio’s duration will be within the zero to five year range at any time. The Portfolio may invest in instruments of any maturity or duration.
The Portfolio may invest without limit in high yield securities (“junk bonds”) rated below Baa by Moody’s Investor Services (“Moody’s”), or equivalently rated by Standard & Poor’s (“S&P”) or Fitch Ratings, Inc. (“Fitch”) or, if unrated, determined by PIMCO to be of comparable quality. Subject to the limitations set forth in this prospectus, the Portfolio may invest in foreign (non-U.S.) currencies, securities denominated in foreign (non-U.S.) currencies, U.S. dollar denominated securities of foreign issuers, and securities and instruments of issuers that are economically tied to emerging market countries. The Portfolio may invest without limit in securities issued or guaranteed by the U.S. Government, its agencies or instrumentalities. Certain of these securities issued by U.S. Government-sponsored entities may not be backed by the full faith and credit of the U.S. Government. The Portfolio may invest without limit in mortgage-related and other asset-backed securities, including mortgage-related and other asset-backed securities issued or guaranteed by the U.S. Government, its agencies or instrumentalities.
The Portfolio may invest without limit in derivative instruments, such as options, futures contracts or swap agreements, which may relate to fixed income securities, interest rates, currencies or currency exchange

PIMCO Managed Accounts Trust | Prospectus 17

Fixed Income SHares: Series LD

rates, commodities, real estate and other assets, and related indices. The Portfolio may lend its portfolio securities to brokers, dealers and other financial institutions to earn income. Although the Portfolio may invest in derivatives of any kind, it expects to invest in futures contracts, swaps and forward foreign currency contracts and to write (sell) put and call options on securities for hedging, risk management or other purposes, including for the purpose or having the effect of creating leverage. The Portfolio may, without limitation, seek to obtain market exposure by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on its investments, plus capital appreciation, if any, generally arising from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest in preferred securities.
The Portfolio will not change its policy to, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in U.S. and foreign fixed income securities of varying maturities unless the Portfolio provides shareholders with the notice required by Rule 35d-1 under the Investment Company Act of 1940, as it may be amended or interpreted by the Securities and Exchange Commission (the “SEC”) from time to time (the “1940 Act”).
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below:
Small Portfolio Risk: the risk that a smaller portfolio may not achieve investment or trading efficiencies. Additionally, a smaller portfolio may be more adversely affected by large purchases or redemptions of portfolio shares
Interest Rate Risk: the risk that fixed income securities will fluctuate in value because of a change in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, or the issuer or guarantor of collateral, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Foreign (Non-U.S.) Investment Risk: the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of
portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, political changes, diplomatic developments or the imposition of sanctions and other similar measures. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Mortgage-Related and Other Asset-Backed Securities Risk: the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk. The Portfolio may invest in any tranche or mortgage-related and other asset-backed securities, including junior and/or equity tranches (to the extent consistent with the other of the Portfolio's guidelines), which generally carry higher levels of the foregoing risks
Emerging Markets Risk: the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Focused Investment Risk: the risk that, to the extent that the Portfolio focuses its investments in a particular sector, it may be susceptible to loss due to adverse developments affecting that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to market developments, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region
Derivatives Risk: the risk of investing in derivative instruments (such as forwards, futures, swaps and structured securities) and other similar investments, including leverage, liquidity, interest rate, market, counterparty (including credit), operational, legal and management risks, and valuation complexity. Changes in the value of a derivative or other similar investment may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. Changes in the value of a derivative or other similar instrument may also create margin delivery or settlement payment obligations for the Portfolio. The Portfolio’s use of derivatives or other similar investments may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Non-centrally-cleared over-the-counter (“OTC”) derivatives or other similar investments are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for non-centrally-cleared OTC derivatives or other similar investments. The primary credit risk on derivatives or other similar investments that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a registered fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives or

18  Prospectus | PIMCO Managed Accounts Trust

Prospectus

other similar investments and/or adversely affect the value of derivatives or other similar investments and the Portfolio’s performance
Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio managers in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Currency Risk: the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Municipal Securities Risk: the risk that investing in municipal securities subjects the Portfolio to certain risks, including variations in the quality of municipal securities, both within a particular classification and between classifications. The rates of return on municipal securities can depend on a variety of factors, including general money market conditions, the financial condition of the issuer, general conditions of the municipal bond market, the size of a particular offering, the maturity of the obligation and the rating of the issue
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, changes in financial condition or credit rating, financial leverage, reputation or reduced demand for the issuer’s goods or services
Turnover Risk: the risk that high levels of portfolio turnover may increase transaction costs and taxes and may lower investment performance
Inflation/Deflation Risk: the risk that the value of assets or income from a Portfolio's investments will be worth less in the future as inflation decreases the value of payments at future dates. As inflation increases, the real value of a Portfolio's investments could decline. Deflation risk is the risk that prices throughout the economy decline over time. Deflation may have an adverse effect on the creditworthiness of issuers and may make issuer default more likely, which may result in a decline in the value of a Portfolio's investments
LIBOR Transition Risk: the risk related to the discontinuation and replacement of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely or relied in some fashion upon LIBOR. Although the transition process away from LIBOR for most instruments has been completed, some LIBOR use is continuing and there are potential effects related to the transition away from LIBOR or the continued use of LIBOR on the Portfolio, or on certain instruments in which the Portfolio invests, which can be difficult to ascertain and could result in losses to the Portfolio
Collateralized Loan Obligations Risk: the risk that investing in collateralized loan obligations (“CLOs”) and other similarly structured investments exposes the Portfolio to heightened credit risk, interest rate risk, liquidity risk, market risk and prepayment and extension risk, as well as the risk of default on the underlying asset. In addition, investments in CLOs carry additional risks including, but not limited to: (i) the possibility that distributions from collateral securities will not be adequate to make interest or other payments; (ii) the quality of the collateral may decline in value or default; (iii) risks related to the capability of the servicer of the securitized assets; (iv) the risk that the Portfolio may invest in tranches of CLOs that are subordinate to other tranches; (v) the structure and complexity of the transaction and the legal documents may not be fully understood at the time of investment and could lead to disputes with the issuer or among investors regarding the characterization of proceeds or unexpected investment results; and (vi) the CLO's manager may perform poorly
Please see “Description of Principal Risks” for more information regarding the risks associated with investing in the Portfolio. An investment in the Portfolio is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual total returns compare with the returns of a broad-based securities market index. Absent any applicable fee waivers and/or expense limitations, performance would have been lower. The information in the bar chart

May 1, 2024 | Prospectus 19

Fixed Income SHares: Series LD

and Average Annual Total Returns Table does not reflect payment of any applicable “wrap” fees by clients of “wrap-fee” programs that invest in the Portfolio to the program sponsors. The Portfolio’s past performance, before and after taxes, is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s benchmark is the ICE BofAML 1-3 Year U.S. Treasury Index. The ICE BofAML 1-3 Year U.S. Treasury Index is an unmanaged index comprised of U.S. Treasury securities, other than inflation-protection securities and STRIPS, with at least $1 billion in outstanding face value and a remaining term to final maturity of at least one year and less than three years. It is not possible to invest directly in an index.
Calendar Year Total Returns
Best Quarter
June 30, 2020
7.08 %
Worst Quarter
March 31, 2020
- 3.87 %
Average Annual Total Returns (for periods ended 12/31/23)
 
1 Year
5 Years
10 Years
Fixed Income SHares: Series LD - Before Taxes
6.07 %
2.11 %
2.70 %
Fixed Income SHares: Series LD - After Taxes on
Distributions (1)
4.63 %
0.73 %
1.04 %
Fixed Income SHares: Series LD - After Taxes on
Distributions and Sale of Portfolio Shares (1)
3.57 %
1.04 %
1.33 %
ICE BofAML 1-3 Year U.S. Treasury Index (reflects no
deductions for fees, expenses or taxes)
4.26 %
1.30 %
1.05 %
1
After-tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from tax returns shown. After-tax returns are not relevant to investors who hold their shares through tax advantaged arrangements such as 401(k) plans or individual retirement accounts. In some cases the return after taxes may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of Portfolio shares at the end of the measurement period.
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser and administrator for the Portfolio. The Portfolio is jointly and primarily managed by Jerome Schneider and Andrew Wittkop. Mr. Schneider is a Managing Director in PIMCO’s Newport Beach office and head of the short-term portfolio management and funding. Mr. Wittkop is an Executive Vice President and portfolio manager in PIMCO’s Newport Beach office. They have managed the Portfolio since its inception in December 2013.
Other Important Information Regarding Portfolio Shares
For important information about purchase and sale of Portfolio shares and tax information, please turn to the “Summary of Other Important Information Regarding Portfolio Shares” section on page 21 of this prospectus.

20  Prospectus | PIMCO Managed Accounts Trust

Summary of Other Important Information Regarding Portfolio Shares

Purchase and Sale of Portfolio Shares
Shares of the Portfolio may be purchased only by or on behalf of “wrap” account clients where PIMCO or Virtus Fund Advisers, LLC (each, as applicable, the “Wrap Program Adviser”) has an agreement to serve as investment adviser or sub-adviser to the account with the wrap program sponsor (typically a registered investment adviser, bank or broker-dealer) or directly with the client. A client agreement to open an account typically may be obtained by contacting the wrap program sponsor. Minimum investment amounts for investing in a Portfolio can be found in the wrap-fee brochure provided to you by the wrap program sponsor or your investment adviser. Generally, purchase and redemption orders for Portfolio shares are processed at the net asset value (“NAV”) next calculated after the broker-dealer who executes trades for the applicable wrap account receives the order on behalf of the account. Orders received by the broker-dealer prior to the time the Portfolio’s NAV is determined on a business day will be processed at that day’s NAV, even if the order is received by the transfer agent after the Portfolio’s NAV has been calculated that day, as long as the order is received by the transfer agent prior to such time as agreed upon by the transfer agent and the broker-dealer.
Tax Information
Except as noted below, each Portfolio’s distributions are generally taxable to you as ordinary income, capital gains or a combination of the two, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account, in which case distributions may be taxable upon withdrawal.
FISH Series TE Portfolio intends to make distributions that consist of exempt-interest dividends, which are generally not taxable to shareholders for federal income tax purposes, but a portion of its distributions may be subject to the federal AMT. A portion of that Portfolio’s distributions may not qualify as exempt-interest dividends; such distributions will generally be taxable to shareholders as ordinary income or capital gains.
Additional Information About the Portfolios
The Portfolios’ investment adviser is PIMCO. Developed by PIMCO exclusively for use within separately managed accounts, the Portfolios represent shares of specialized bond portfolios. They are used in combination with selected individual securities to effectively model institutional-level investment strategies. The Portfolios can permit greater diversification than smaller managed accounts might otherwise achieve. PIMCO uses these specialized bond portfolios within the PIMCO Total Return, PIMCO Real Return, PIMCO National Intermediate Municipal Bond, PIMCO Municipal Bond and PIMCO Low Duration managed account portfolios as follows.
Within the PIMCO Total Return managed account portfolio:
Fixed Income SHares: Series C, normally investing substantially all (and at least 80%) of its net assets (plus borrowings made for investment purposes) in a portfolio of U.S. and foreign fixed income instruments.
Fixed Income SHares: Series M, normally investing at least 80% of its net assets (plus borrowing made for investment purposes) in a portfolio of U.S. and foreign fixed income instruments of varying maturities.
Within the PIMCO Real Return managed account portfolio:
Fixed Income SHares: Series R, normally investing at least 80% of its net assets (plus borrowing made for investment purposes) in a portfolio of U.S. and foreign fixed income instruments.
Within the PIMCO National Intermediate Municipal Bond and PIMCO Municipal Bond managed account portfolios:
Fixed Income SHares: Series TE, normally investing at least 80% of its net assets (plus borrowings made for investment purposes) in a portfolio of U.S. fixed income instruments comprised of debt securities whose interest is, in the opinion of bond counsel for the issuer at the time of issuance, exempt from federal income tax ( i.e. , excluded from gross income for federal income tax purposes but not necessarily exempt from the federal alternative minimum tax).
Within the PIMCO Low Duration managed account portfolio:
Fixed Income SHares: Series LD, normally investing at least 80% of its net assets (plus borrowings made for investment purposes) in a diversified portfolio of U.S. and foreign fixed income securities of varying maturities and normally maintaining an average portfolio duration between zero and five years; however, the duration of the Portfolio will vary based on PIMCO’s forecast for interest rates.
Descriptions of different Portfolios should be read independently of one another. How or whether a particular Portfolio utilizes an investment strategy, technique or instrument should not be inferred from how or whether other Portfolios are described as utilizing the same investment strategy, technique or instrument in their descriptions.

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Description of Principal Risks
The value of your investment in a Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on a particular Portfolio are called “principal risks.” The principal risks of each Portfolio identified in the Portfolio Summaries and in the table below are described further in this section. Each Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by a Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques” or in the Statement of Additional Information (“SAI”). That section and “Investment Objectives and Policies” in the SAI also include more information about the Portfolios, their investments and the related risks. There is no guarantee that a Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in a Portfolio.
Principal Risk
FISH: Series C
FISH: Series M
FISH: Series R
FISH: Series TE
FISH: Series LD
Small Portfolio
x
x
Interest Rate
x
x
x
x
x
Credit
x
x
x
x
x
Market
x
x
x
x
x
Foreign (Non-U.S.) Investment
x
x
x
x
Mortgage-Related and Other Asset-Backed Securities
x
x
x
x
Emerging Markets
x
x
x
x
Focused Investment
x
x
x
x
x
Derivatives
x
x
x
x
x
Liquidity
x
x
x
x
x
Management
x
x
x
x
x
High Yield
x
x
x
x
x
Currency
x
x
x
x
Leveraging
x
x
x
x
x
Issuer
x
x
x
x
x
Turnover
x
x
x
x
Municipal Securities
x
x
x
x
x
Municipal Project-Specific
x
Municipal Bond Market
x
California State Specific
x
New York State-Specific
x
Puerto Rico-Specific
x
Sovereign Debt
x
Inflation/Deflation
x
x
x
x
x
Contingent Convertible Securities
x
x
LIBOR Transition
x
x
x
Collateralized Loan Obligations
x
x
x
AMT Bonds
x
AMT Bonds Risk
To the extent that a Portfolio may invest in “AMT Bonds,” which are municipal securities that pay interest that is taxable under the federal alternative minimum tax applicable to noncorporate taxpayers, such investments may expose the Portfolio to certain risks in addition to those typically associated with municipal bonds. Interest or principal on AMT Bonds paid out of current or anticipated revenues from a specific project or specific asset may be adversely impacted by declines in revenue from the project or asset. Declines in general business activity could also affect the economic viability of facilities that are the sole source of revenue to support AMT Bonds. In this regard, AMT Bonds may entail greater risks than general obligation municipal bonds. For shareholders subject to the federal alternative minimum tax, a portion of the Portfolio’s distributions may not be exempt from gross federal income, which may give rise to alternative minimum tax liability.

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California State-Specific Risk
To the extent a Portfolio concentrates its investments in California Municipal Bonds, the Portfolio may be affected significantly by political, economic, regulatory, social, environmental, or public health developments affecting the ability of California tax exempt issuers to pay interest or repay principal. Certain issuers of California Municipal Bonds have experienced serious financial difficulties in the past and reoccurrence of these difficulties may impair the ability of certain California issuers to pay principal or interest on their obligations. Provisions of the California Constitution and state statutes that limit the taxing and spending authority of California governmental entities may impair the ability of California issuers to pay principal and/or interest on their obligations. While California’s economy is broad, it does have major concentrations in advanced technology, aerospace and defense-related manufacturing, trade, entertainment, real estate and financial services, and may be sensitive to economic problems affecting those industries. Future California political and economic developments, constitutional amendments, legislative measures, executive orders, administrative regulations, litigation and voter initiatives, as well as environmental events, natural disasters, pandemics, epidemics or social unrest, could have an adverse effect on the debt obligations of California issuers.
Collateralized Loan Obligations Risk
Certain Portfolios may invest in collateralized loan obligation (“CLOs”) and other similarly structured investments. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. In addition to the risks associated with investment in such underlying assets, the structure and characteristics of a CLO present certain additional risks. A Portfolio’s investments in CLOs and other similarly structured investments may expose the Portfolio to heightened credit risk, interest rate risk, liquidity risk, market risk and prepayment and extension risk, as well as the risk of default on the underlying asset. In addition, investments in CLOs carry additional risks including, but not limited to: (i) the possibility that distributions from collateral securities will not be adequate to make interest or other payments; (ii) the quality of the collateral may decline in value or default; (iii) risks related to the capability of the servicer of the securitized assets; (iv) the risk that a Portfolio may invest in tranches of CLOs that are subordinate to other tranches; (v) the structure and complexity of the transaction and the legal documents may not be fully understood at the time of investment and could lead to disputes with the issuer or among investors regarding the characterization of proceeds or unexpected investment results; and (vi) the CLO’s manager may perform poorly. CLOs may charge management and other administrative fees, which are in addition to those of a Portfolio.
The cash flows from a CLO are split into two or more portions, called tranches, varying in risk and yield. The riskiest portion is the “equity” tranche which bears the first loss of any defaults from the bonds or loans in the trust, although more senior tranches may also bear losses. Since they are partially protected from defaults, senior tranches from a CLO typically have higher ratings and lower yields than their underlying securities, and can be rated investment grade. Despite the protection from the equity tranche, CLO tranches can experience substantial losses due to actual defaults, increased sensitivity to defaults due to collateral default and disappearance of protecting tranches, market anticipation of defaults, as well as aversion to CLO securities as a class. The risks of an investment in a CLO depend largely on the type of the collateral securities and the class of the instrument in which a Portfolio invests. Typically, CLOs are privately offered and sold, and thus, are not registered under the securities laws.
Contingent Convertible Securities Risk
Contingent convertible securities (“CoCos”) have no stated maturity, have fully discretionary coupons and are typically issued in the form of subordinated debt instruments. CoCos generally either convert into equity or have their principal written down (including potentially to zero) upon the occurrence of certain triggering events (“triggers”) linked to regulatory capital thresholds or regulatory actions relating to the issuer’s continued viability. As a result, an investment by the Portfolio in CoCos is subject to the risk that coupon ( i.e. , interest) payments may be cancelled by the issuer or a regulatory authority in order to help the issuer absorb losses and the risk of total loss. An investment by the Portfolio in CoCos is also subject to the risk that, in the event of the liquidation, dissolution or winding-up of an issuer prior to a trigger event, the Portfolio’s rights and claims will generally rank junior to the claims of holders of the issuer’s other debt obligations and CoCos may also be treated as junior to an issuer’s other obligations and securities. In addition, if CoCos held by the Portfolio are converted into the issuer’s underlying equity securities following a trigger event, the Portfolio’s holding may be further subordinated due to the conversion from a debt to equity instrument. Further, the value of an investment in CoCos is unpredictable and will be influenced by many factors and risks, including interest rate risk, credit risk, market risk and liquidity risk. An investment by the Portfolio in CoCos may result in losses to the Portfolio.
Credit Risk
A Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities , or the issuer or guarantor of collateral, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The risk that such issuer, guarantor or counterparty is less willing or able to do so is heightened in market environments where interest rates are rising. The downgrade of the credit rating of a security or of the issuer of

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a security held by a Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings . Measures such as average credit quality may not accurately reflect the true credit risk of a Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if a Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. Credit risk is greater to the extent the Portfolio uses leverage or derivatives. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest. Rising or high interest rates may deteriorate the credit quality of an issuer or counterparty, particularly if an issuer or counterparty faces challenges rolling or refinancing its obligations.
Currency Risk
If a Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies , or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies , it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar, will decline in value relative to the currency being hedged. Although a Portfolio may attempt to hedge its currency exposure into the U.S. dollar, it may not be successful in reducing the effects of currency fluctuations. A Portfolio may also hedge from one foreign currency to another. In addition, a Portfolio’s use of currency hedging may not be successful and the use of such strategies may lower a Portfolio’s potential returns.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance of payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, a Portfolio’s investments in or exposure to foreign (non-U.S.) currencies and/or foreign (non-U.S.) currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that a Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Derivatives Risk
Derivatives and other similar instruments (referred to collectively as “derivatives”) are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolios may use are referenced under “Characteristics and Risks of Securities and Investment Techniques — Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolios typically use derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolios may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject a Portfolio to the potential for unlimited loss. The use of derivatives may cause a Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
A Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, leverage risk, counterparty (including credit) risk, operational risk (such as documentation issues, settlement issues and systems failures), legal risk (such as insufficient capacity or authority of a counterparty, and issues with the legality or enforceability of a contract), and management risk, as well as risks arising from changes in applicable requirements, risks arising from margin requirements and risks arising from mispricing or valuation complexity. They also involve the risk of unfavorable or ambiguous documentation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. By investing in a derivative instrument, a Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. The 1940 Act and related rules no longer require asset segregation for derivatives transactions, however asset segregation and posting of collateral may still be utilized for risk management or other purposes. A Portfolio may be required to hold additional cash or sell other investments in order to obtain cash to close out a position and changes in the value of a derivative may also create margin delivery or settlement payment obligations for the Portfolio. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that a Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, a Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Non-centrally-cleared over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not

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fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for non-centrally-cleared OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which a Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If a Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of a Portfolio and its counterparty. Therefore, it may not be possible for a Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, a Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a Portfolio may wish to retain its position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, a Portfolio will be subject to increased liquidity and investment risk.
The Portfolios may invest in commodity-linked derivative instruments to the extent that the Portfolios’ exposure to commodities through these instruments is 5% or less of the Portfolio’s total assets at the time of investment (although the Portfolios may invest directly in other commodity-related investments independent of this restriction). The Portfolios’ investments in commodity-linked derivative instruments may subject the Portfolios to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, embargoes, tariffs and international economic, political and regulatory developments.
The Portfolios may invest in real-estate linked derivative instruments to the extent that a Portfolio’s exposure to real estate through these instruments is 5% or less of the Portfolios’ total assets at the time of investment (although the Portfolio may invest directly in other real estate-related investments independent of this restriction). To the extent the Portfolios invest in real estate-linked derivative instruments, they are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses.
When a derivative is used as a hedge against a position that a Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that a Portfolio’s hedging transactions will be effective. Derivatives used for hedging or risk management may not operate as intended or may expose a Portfolio to additional risks. In addition, derivatives used for hedging may partially protect a Portfolio from the risks they were intended to hedge yet not fully mitigate the impact of such risks.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of a Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities . Emerging market securities may present market, credit, currency, liquidity, volatility, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. A Portfolio that focuses its investments in multiple asset classes of emerging market securities may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established regulatory, disclosure, legal, accounting, recordkeeping and financial reporting systems than those in

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more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments, or to obtain information needed to pursue or enforce such judgments, against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. In addition, foreign companies with securities listed on U.S. exchanges may be delisted if they do not meet U.S. accounting standards and auditor oversight requirements, which may decrease the liquidity and value of the securities.
A Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities . Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Focused Investment Risk
To the extent that a Portfolio focuses its investments in a particular sector, it may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to: governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, a Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. A Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Foreign (Non-U.S.) Investment Risk
Foreign (non-U.S.) securities may experience more rapid and extreme changes in value than securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, legal, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Foreign (non-U.S.) market trading hours, clearance and settlement procedures, and holiday schedules may limit a Portfolio’s ability to buy and sell securities. Investments in foreign (non-U.S.) markets may also be adversely affected by governmental actions such as the imposition of capital controls, nationalization of companies or industries, expropriation of assets or the imposition of punitive taxes. The governments of certain countries may prohibit or impose substantial restrictions on foreign (non-U.S.) investing in their capital markets or in certain sectors or industries. In addition, a foreign (non-U.S.) government may limit or cause delay in the convertibility or repatriation of its currency which would adversely affect the U.S. dollar value and/or liquidity of investments denominated in that currency. Certain foreign (non-U.S.) investments may become less liquid in response to market developments or adverse investor perceptions, or become illiquid after purchase by a Portfolio, particularly during periods of market turmoil. A reduction in trading in securities of issuers located in countries whose economies are heavily dependent upon trading with key partners may have an adverse impact on a Portfolio's investments. Also, nationalization, expropriation or confiscatory taxation, unstable governments, decreased market liquidity, currency blockage, market disruptions, political changes, security suspensions, diplomatic developments or the imposition of sanctions or other similar measures could adversely affect a Portfolio’s investments in a foreign (non-U.S.) country. In the event of nationalization, expropriation or other confiscation, a Portfolio could lose its entire investment in foreign (non-U.S.) securities. The type and severity of sanctions and other similar measures, including counter sanctions and other retaliatory actions, that may be imposed could vary broadly in scope, and their impact is difficult to ascertain. These types of measures may include, but are not limited to, banning a sanctioned country or certain persons or entities associated with such country from global payment systems that facilitate cross-border payments, restricting the settlement of securities transactions by certain investors, and freezing the assets of particular countries, entities or persons. The imposition of sanctions and other similar measures could, among other things, result in a decline in the value and/or liquidity of securities issued by the sanctioned country or companies located in or economically tied to the sanctioned country, downgrades in the credit ratings of the sanctioned country's securities or those of companies located in or economically tied to the sanctioned country, currency devaluation or volatility, and increased market volatility and disruption in the sanctioned country and throughout the world. Sanctions and other similar measures could directly or indirectly limit or prevent a Portfolio from buying and selling securities (in the sanctioned country and other markets), significantly delay or prevent the settlement of securities transactions and adversely impact a Portfolio's liquidity and performance. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that a Portfolio

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Prospectus

invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid (particularly during market closures due to local holidays or other reasons) and more difficult to value than securities of U.S. issuers.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce a Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require a Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in a Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. A Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities . In addition, the high yield securities in which a Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in a Portfolio being unable to realize full value for these securities and/or may result in a Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to a Portfolio. In addition, adverse publicity and investor perceptions, whether or not based on fundamental analysis, may decrease the values and liquidity of high yield securities, especially in thinly-traded markets. When secondary markets for high yield securities are less liquid than the market for other types of securities, it may be more difficult to value the securities because such valuation may require more research, and elements of judgments may play a greater role in the valuation because there is less reliable, objective data available. Because of the risks involved in investing in high yield securities , an investment in Portfolios that invest in such securities should be considered speculative.
Inflation/Deflation Risk
Inflation risk is the risk that the value of assets or income from a Portfolio's investments will be worth less in the future as inflation decreases the value of payments at future dates. As inflation increases, the real value of a Portfolio's investments could decline. Inflation has recently increased and it cannot be predicted whether it may decline. Deflation risk is the risk that prices throughout the economy decline over time. Deflation may have an adverse effect on the creditworthiness of issuers and may make issuer default more likely, which may result in a decline in the value of a Portfolio's investments.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities, dividend-paying equity securities and other instruments in a Portfolio’s portfolio will fluctuate in value because of a change in interest rates. For example, as nominal interest rates rise, the value of certain fixed income securities held by a Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and a Portfolio may lose money as a result of movements in interest rates. A Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended. Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates.
Inflation-indexed bonds , including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Dividend-paying equity securities, particularly those whose market price is closely related to their yield, may be more sensitive to changes in interest rates. During periods of rising interest rates, the values of such securities may decline and may result in losses to the Portfolio.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility

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than a fixed rate obligation with similar credit quality. When a Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the NAV of the Portfolio’s shares. Dividend-paying equity securities, particularly those whose market price is closely related to their yield, may be more sensitive to changes in interest rates. During periods of rising interest rates, the values of such securities may decline, which may result in losses to the Portfolio.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments. Risks associated with rising interest rates are heightened under recent market conditions, including because the U.S. Federal Reserve (the “Federal Reserve”) has raised interest rates from historically low levels and the U.S. and other governments have increased, and are likely to continue increasing, their debt issuances. There is the risk that the income generated by investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates. Periods of higher inflation could cause such authorities to raise interest rates, which may adversely affect a Portfolio and its investments. In addition, changes in monetary policy may exacerbate the risks associated with changing interest rates. Further, in market environments where interest rates are rising, issuers may be less willing or able to make principal and interest payments on fixed income investments when due.
Rising interest rates may result in a decline in value of a Portfolio’s fixed income investments and in periods of volatility. Further, while U.S. bond markets have steadily grown over the past three decades, dealer “market making” ability has remained relatively stagnant. As a result, dealer inventories of certain types of bonds and similar instruments, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty. All of these factors, collectively and/or individually, could cause a Portfolio to lose value.
During periods of very low or negative interest rates, a Portfolio may be unable to maintain positive returns. Certain European countries have previously experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from Portfolio performance to the extent a Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of a Portfolio. This is especially the case if a Portfolio consists of securities with widely varying durations. Therefore, if a Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or Portfolio’s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if a Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, major litigation, investigations or other controversies, changes in the issuer’s financial condition or credit rating, changes in government regulations affecting the issuer or its competitive environment and strategic initiatives such as mergers, acquisitions or dispositions and the market response to any such initiatives, financial leverage, reputation or reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect one or more other issuers or securities markets as a whole.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities , and the use of when-issued, delayed delivery or forward commitment transactions . The use of derivatives may also create leveraging risk. A Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause a Portfolio to liquidate portfolio positions to satisfy its obligations when it may not be advantageous to do so. Leverage, including borrowing , may cause a Portfolio to be more volatile than if a Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box” ( i.e ., short sales where a Portfolio does not hold the security or have the right to acquire it without payment of further consideration), could

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theoretically be subject to unlimited losses in cases where a Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent a Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed a Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, a Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so. Leveraging transactions pursued by a Portfolio may increase its duration and sensitivity to interest rate environments.
LIBOR Transition Risk
Certain instruments in which a Portfolio may invest have relied or continue to rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR was traditionally an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On March 5, 2021, the Financial Conduct Authority (“FCA”), the United Kingdom's financial regulatory body and regulator of LIBOR, publicly announced that all U.S. Dollar LIBOR settings will either cease to be provided by any administrator or will no longer be representative (i) immediately after December 31, 2021 for one-week and two-month U.S. Dollar LIBOR settings and (ii) immediately after June 30, 2023 for the remaining U.S. Dollar LIBOR settings. As of January 1, 2022, as a result of supervisory guidance from U.S. regulators, U.S. regulated entities have generally ceased entering into new LIBOR contracts with limited exceptions. Publication of all Japanese yen and the one- and six-month sterling LIBOR settings have ceased, and while publication of the three-month Sterling LIBOR setting will continue through at least the end of March 2024 on the basis of a changed methodology (known as “synthetic LIBOR”), this rate has been designated by the FCA as unrepresentative of the underlying market that it seeks to measure and is solely available for use in legacy transactions. Certain bank-sponsored committees in other jurisdictions, including Europe, the United Kingdom, Japan and Switzerland, have selected alternative reference rates denominated in other currencies. Although the transition process away from LIBOR for many instruments has been completed, some LIBOR use is continuing and there are potential effects related to the transition away from LIBOR or continued use of LIBOR on a Portfolio, or on certain instruments in which a Portfolio invests, which can be difficult to ascertain, and may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants adopt new reference rates for affected instruments. So called “tough legacy” contracts have LIBOR interest rate provisions with no fallback provisions contemplating a permanent discontinuation of LIBOR, inadequate fallback provisions or fallback provisions which may not effectively result in a transition away from LIBOR prior to LIBOR's planned replacement date. On March 15, 2022, the Adjustable Interest Rate (LIBOR) Act was signed into law. This law provides a statutory fallback mechanism on a nationwide basis to replace LIBOR with a benchmark rate that is selected by the Board of Governors of the Federal Reserve System based on the Secured Overnight Financing Rate (“SOFR”) for tough legacy contracts. On February 27, 2023, the Federal Reserve System's final rule in connection with this law became effective, establishing benchmark replacements based on SOFR and Term SOFR (a forward-looking measurement of market expectations of SOFR implied from certain derivatives markets) for applicable tough legacy contracts governed by U.S. law. In addition, the FCA has announced that it will require the publication of synthetic LIBOR for the one-month, three-month and six-month U.S. Dollar LIBOR settings after June 30, 2023 through at least September 30, 2024. Certain of the Portfolio's investments may involve individual tough legacy contracts which may be subject to the Adjustable Interest Rate (LIBOR) Act or synthetic LIBOR and no assurances can be given that these measures will have had the intended effects. Moreover, certain aspects of the transition from LIBOR have relied or will continue to rely on the actions of third-party market participants, such as clearing houses, trustees, administrative agents, asset servicers and certain service providers; PIMCO cannot guarantee the performance of such market participants and any failure on the part of such market participants to manage their part of the LIBOR transition could impact the Portfolios. The transition of investments from LIBOR to a replacement rate as a result of amendment, application of existing fallbacks, statutory requirements or otherwise may also result in a reduction in the value of certain instruments held by a Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of a Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to a Portfolio.
Liquidity Risk
The Securities and Exchange Commission (“SEC”) defines liquidity risk as the risk that a Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in a Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that a Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. A Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require a Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make

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markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, a Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that a Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities , Rule 144A securities, illiquid sectors of fixed income securities , derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for a Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require a Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as a Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of a Portfolio’s shares. Redemptions by these shareholders of their holdings in a Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force a Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Liquidity risk also refers to the risk that a Portfolio may be required to hold additional cash or sell other investments in order to obtain cash to close out derivatives or meet the liquidity demands that derivatives can create to make payments of margin, collateral, or settlement payments to counterparties. A Portfolio may have to sell a security at a disadvantageous time or price to meet such obligations. Actions by governments and regulators may have the effect of reducing market liquidity, market resiliency and money supply, such as through higher rates, tighter financial regulations and proposals related to open-end fund liquidity that may prevent mutual funds and exchange-traded funds from participating in certain markets.
Management Risk
Each Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolios, or may determine that certain factors are more significant than others. There can be no guarantee that these decisions will produce the desired results or that the due diligence conducted by PIMCO, or such other investment adviser or sub-adviser, as applicable, and individual portfolio managers will expose all material risks associated with an investment. Additionally, PIMCO, or such other investment adviser or sub-adviser, as applicable, and individual portfolio managers may not be able to identify suitable investment opportunities and may face competition from other investment managers when identifying and consummating certain investments. Certain securities or other instruments in which a Portfolio seeks to invest may not be available in the quantities desired, including in circumstances where other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies, and/or portfolio management teams, similar to a Portfolio, are seeking to invest in the same or similar securities or instruments. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent a Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. Each Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systemic) could prevent a Portfolio from purchasing a security expected to appreciate in value. Please refer to “Portfolio Managers – Conflicts of Interest” in the SAI for further information. Additionally, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolios and may also adversely affect the ability of the Portfolios to achieve their investment objectives. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of services of one or more key employees of PIMCO could have an adverse impact on a Portfolio’s ability to realize its investment objective.
In addition, a Portfolio may rely on various third-party sources to calculate its NAV. As a result, a Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculations of its NAV, and such NAV calculation issues may result in inaccurately calculated NAVs, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. A Portfolio may be unable to recover any losses associated with such failures.

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Market Risk
The market price of securities owned by a Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries or issuers represented in the securities markets. The value of a security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously even if the performance of those asset classes is not otherwise historically correlated. Investments may also be negatively impacted by market disruptions and by attempts by other market participants to manipulate the prices of particular investments. Equity securities generally have greater price volatility than fixed income securities . Credit ratings downgrades may also negatively affect securities held by a Portfolio. Even when markets perform well, there is no assurance that the investments held by a Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, social unrest, recessions, supply chain disruptions, market manipulation, government defaults, government shutdowns, political changes, diplomatic developments or the imposition of sanctions and other similar measures, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolios to lose value. These events could reduce consumer demand or economic output, result in market closures, changes in interest rates, inflation/deflation, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on a Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect a Portfolio’s investments. Any market disruptions could also prevent a Portfolio from executing advantageous investment decisions in a timely manner. Portfolios that have focused their investments in a region enduring geopolitical market disruption will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether a Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to a Portfolio that may invest in fixed income securities. As discussed more under “Interest Rate Risk,” the Federal Reserve has raised interest rates from historically low levels. In addition, changes in monetary policy may exacerbate the risks associated with changing interest rates. Any additional interest rate increases in the future could cause the value of any Portfolio that invests in fixed income securities to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause a Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Although interest rates have significantly increased since 2022 through the date of this prospectus, the prices of real estate-related assets generally have not decreased as much as may be expected based on historical correlations between interest rates and prices of real estate-related assets. This presents an increased risk of a correction or severe downturn in real estate-related asset prices, which could adversely impact the value of other investments as well (such as loans, securitized debt and other fixed income securities). This risk is particularly present with respect to commercial real estate-related asset prices, and the value of other investments with a connection to the commercial real estate sector. As examples of the current risks faced by real estate-related assets; tenant vacancy rates, tenant turnover and tenant concentration have increased; owners of real estate have faced headwinds, delinquencies and difficulties in collecting rents and other payments (which increases the risk of owners being unable to pay or otherwise defaulting on their own borrowings and obligations); property values have declined; inflation, upkeep costs and other expenses have increased; and rents have declined for many properties.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities, or generally which may result in, among other things, a Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments.

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Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. Compared to other fixed income investments with similar maturity and credit, mortgage-related securities may increase in value to a lesser extent when interest rates decline and may decline in value to a similar or greater extent when interest rates rise. As a result, in a period of rising interest rates, if a Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing a Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of a Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. In addition, the creditworthiness, servicing practices, and financial viability of the servicers of the underlying mortgage pools present significant risks. For instance, a servicer may be required to make advances in respect of delinquent loans underlying the mortgage-related securities ; however, servicers experiencing financial difficulties may not be able to perform these obligations. Additionally, both mortgage-related securities and asset-backed securities are subject to risks associated with fraud or negligence by, or defalcation of, their servicers. These securities are also subject to the risks of the underlying loans. In some circumstances, a servicer’s or originator’s mishandling of documentation related to the underlying collateral (e.g., failure to properly document a security interest in the underlying collateral) may affect the rights of security holders in and to the underlying collateral. In addition, the underlying loans may have been extended pursuant to inappropriate underwriting guidelines, to no underwriting guidelines at all, or to fraudulent origination practices. The owner of a mortgage-backed security’s ability to recover against the sponsor, servicer or originator is uncertain and is often limited. A Portfolio’s investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. FISH: Series M is particularly sensitive to mortgage risk because the Portfolio normally invests substantially in mortgage-related securities. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets. A Portfolio may invest in a tranche of mortgage-related or other asset-backed securities, including junior and/or equity tranches (to the extent consistent with other of the Portfolio's guidelines), which generally carry higher levels of the foregoing risks.
Additionally, investments in subordinate mortgage-backed and other asset-backed securities will be subject to risks arising from delinquencies and foreclosures, thereby exposing a Portfolio’s investment portfolio to potential losses. Subordinate securities of mortgage-backed and other asset-backed securities are also subject to greater credit risk than those mortgage-backed or other asset-backed securities that are more highly rated.
Municipal Bond Market Risk
A Portfolio that invests in the municipal bond market is subject to certain risks. The amount of public information available about the municipal bonds held by a Portfolio is generally less than that for corporate equities or bonds, and the investment performance of the Portfolio may therefore be more dependent on the analytical abilities of PIMCO than would be a stock fund or taxable bond fund. The secondary market for municipal bonds, also tends to be less well-developed or liquid than many other securities markets, which may adversely affect a Portfolio’s ability to sell its bonds at attractive prices.
The ability of municipal issuers to make timely payments of interest and principal may be diminished during general economic downturns and as governmental cost burdens are reallocated among federal, state and local governments. In addition, laws enacted in the future by Congress or state legislatures or referenda could extend the time for payment of principal and/or interest, or impose other constraints on enforcement of such obligations or on the ability of municipal issuers to levy taxes. Issuers of municipal securities might seek protection under the bankruptcy laws. In the event of bankruptcy of such an issuer, a Portfolio investing in the issuer’s securities could experience delays in collecting principal and interest and the Portfolio may not, in all circumstances, be able to collect all principal and interest to which it is entitled. To enforce its rights in the event of a default in the payment of interest or repayment of principal, or both, a Portfolio may take possession of, and manage, the assets securing the issuer’s obligations on such securities, which may increase the Portfolio’s operating expenses. Any income derived from the Portfolio’s ownership or operation of such assets may not be tax-exempt. More generally, the Portfolios other than FISH: Series TE do not expect to be eligible to pass through to shareholders the tax-exempt character of interest earned on municipal bonds.
Municipal Project-Specific Risk
A Portfolio may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation and utilities), industrial development bonds, or in general obligation bonds, particularly if there is a large concentration from issuers in a single state. This is because the value of municipal securities can be

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significantly affected by the political, economic, legal and legislative realities of the particular issuer’s locality or municipal sector events. In addition, a significant restructuring of federal income tax rates or even serious discussion on the topic in Congress could cause municipal bond prices to fall. The demand for municipal securities is strongly influenced by the value of tax-exempt income to investors. Lower income tax rates could reduce the advantage of owning municipal securities. Similarly, changes to state or federal regulation tied to a specific sector, such as the hospital sector, could have an impact on the revenue stream for a given subset of the market.
Municipal Securities Risk
Municipal securities are debt obligations generally issued to obtain funds for various public purposes, including general financing for state and local governments, or financing for a specific project or public facility. Municipal securities may be fully or partially backed by the taxing authority of the local government, by the credit of a private issuer, by the current or anticipated revenues from a specific project or specific assets or by domestic or foreign entities providing credit support, such as letters of credit, guarantees or insurance, and are generally classified into general obligation bonds and special revenue obligations. General obligation bonds are backed by an issuer’s taxing authority and may be vulnerable to limits on a government’s power or ability to raise revenue or increase taxes. They may also depend for payment on legislative appropriation and/or funding or other support from other governmental bodies. Revenue obligations are payable from revenues generated by a particular project or other revenue source, and are typically subject to greater risk of default than general obligation bonds because investors can look only to the revenue generated by the project or other revenue source backing the project, rather than to the general taxing authority of the state or local government issuer of the obligations. Because many municipal securities are issued to finance projects in sectors such as education, health care, transportation and utilities, conditions in those sectors can affect the overall municipal market. Municipal securities generally pay interest that, in the opinion of bond counsel, is free from U.S. federal income tax (and, in some cases, the federal alternative minimum tax). There is no assurance that the Internal Revenue Service (“IRS”) will agree with this opinion. In the event the IRS determines that the issuer does not comply with relevant tax requirements, interest payments from a security could become federally taxable, possibly retroactively to the date the security was issued, and the value of the security would likely fall. As a shareholder of FISH: Series TE, you may be required to file an amended tax return and pay additional taxes as a result.
Municipal securities are also subject to interest rate, credit and liquidity risk.
Interest Rate risk: The value of municipal securities, similar to other fixed income securities, will likely drop as interest rates rise in the general market. Conversely, when rates decline, bond prices generally rise.
Credit Risk: The risk that a borrower may be unable to make interest or principal payments when they are due. Portfolios that invest in municipal securities rely on the ability of the issuer to service its debt. This subjects a Portfolio to credit risk in that the municipal issuer may be fiscally unstable or exposed to large liabilities that could impair its ability to honor its obligations. Municipal issuers with significant debt service requirements, in the near-to mid-term, unrated issuers and those with less capital and liquidity to absorb additional expenses may be most at risk. A Portfolio that invests in lower quality or high yield municipal securities may be more sensitive to the adverse credit events in the municipal market. The treatment of municipalities in bankruptcy is more uncertain, and potentially more adverse to debt holders, than for corporate issues.
Liquidity Risk: The risk that investors may have difficulty finding a buyer when they seek to sell, and therefore, may be forced to sell at a discount to the market value. Liquidity may sometimes be impaired in the municipal market and Portfolios that primarily invest in municipal securities may find it difficult to purchase or sell such securities at opportune times. Liquidity can be impaired due to interest rate concerns, credit events, or general supply and demand imbalances. These adverse developments sometimes cause a Portfolio to endure higher redemption rates. Depending on the particular issuer and current economic conditions, municipal securities could be deemed more volatile investments.
In addition to general municipal market risks, different municipal sectors may face different risks. For instance, general obligation bonds are secured by the full faith, credit and taxing power of the municipality issuing the obligation. As such, timely payment depends on the municipality’s ability to raise tax revenue and maintain a fiscally sound budget. The timely payments may also be influenced by any unfunded pension liabilities or other post-employee benefit plan liabilities.
Revenue bonds are secured by special tax revenues or other revenue sources. If the specified revenues do not materialize, then the bonds may not be repaid.
Private activity bonds are yet another type of municipal security. Municipalities use private activity bonds to finance the development of industrial facilities for use by private enterprise. Principal and interest payments are to be made by the private enterprise benefiting from the development, which means the holder of the bond is exposed to the risk that the private issuer may default on the bond.
Moral obligation bonds are usually issued by special purpose public entities. If the public entity defaults, repayment becomes a “moral obligation” instead of a legal one. The lack of a legally enforceable right to payment in the event of default poses a special risk for a holder of the bond because it has little or no ability to seek recourse in the event of default.
Municipal notes are similar to general municipal debt obligations, but they generally possess shorter terms. Municipal notes can be used to provide interim financing and may not be repaid if anticipated revenues are not realized.

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New York State-Specific Risk
To the extent a Portfolio concentrates its investments in New York Municipal Bonds , the Portfolio may be affected significantly by economic, regulatory or political developments affecting the ability of New York issuers to pay interest or repay principal. Certain issuers of New York Municipal Bonds have experienced serious financial difficulties in the past and reoccurrence of these difficulties may impair the ability of certain New York issuers to pay principal or interest on their obligations. Provisions of the New York Constitution and State statutes which limit the taxing and spending authority of New York governmental entities may impair the ability of New York issuers to pay principal and/or interest on their obligations. While New York’s economy is broad, it does have major concentrations in certain industries, such as financial services, and may be sensitive to economic problems affecting those industries. Future New York political and economic developments, constitutional amendments, legislative measures, executive orders, administrative regulations, litigation and voter initiatives as well as environmental events, natural disasters, pandemics, epidemics or social unrest could have an adverse effect on the debt obligations of New York issuers to pay principal or interest on their obligations. The financial health of New York City affects that of the State, and when New York City experiences financial difficulty it may have an adverse effect on New York Municipal Bonds held by the Portfolio. The growth rate of New York has at times been somewhat slower than the nation overall. The economic and financial condition of New York also may be affected by various financial, social, economic and political factors.
Puerto Rico-Specific Risk
A Portfolio that invests in Municipal Bonds issued by Puerto Rico or its instrumentalities may be affected by certain developments, such as political, economic, environmental, social, regulatory or debt restructuring developments, that impact the ability or obligation of Puerto Rico municipal issuers to pay interest or repay principal. Certain issuers of Puerto Rico Municipal Bonds have experienced significant financial difficulties and the continuation or reoccurrence of these difficulties may impair their ability to pay principal or interest on their obligations. Provisions of the Puerto Rico Constitution and Commonwealth laws, including a federally-appointed oversight board to oversee the Commonwealth’s financial operations, which limit the taxing and spending authority of Puerto Rico governmental entities, may impair the ability of Puerto Rico issuers to pay principal and/or interest on their obligations. Puerto Rico’s economy has sizable concentrations in certain industries, such as the manufacturing and service industries, and may be sensitive to economic problems affecting those industries. Future Puerto Rico-related developments, such as political and economic developments, constitutional amendments, legislative measures, executive orders, administrative regulations, litigation, debt restructuring, and voter initiatives as well as environmental events, natural disasters, pandemics, epidemics or social unrest could have an adverse effect on the debt obligations of Puerto Rico issuers.
Small Portfolio Risk
A smaller portfolio may not grow to or maintain an economically viable size to achieve investment or trading efficiencies, which may negatively impact performance and/or force the portfolio to liquidate. Additionally, a smaller portfolio may be more adversely affected by large purchases or redemptions of portfolio shares, which can occur at any time and may impact the portfolio in the same manner as a high volume of purchases or redemptions.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to a Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond a Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Turnover Risk
A change in the securities held by a Portfolio is known as “portfolio turnover.” Higher portfolio turnover involves correspondingly greater expenses to a Portfolio, including brokerage commissions or dealer mark-ups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed as ordinary income when distributed to individual shareholders), and may adversely impact a Portfolio’s after-tax returns. The trading costs and tax effects associated with portfolio turnover may adversely affect a Portfolio’s performance.

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Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of each Portfolio’s holdings.

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Management of the Portfolios
Investment Adviser and Administrator
PIMCO serves as the investment adviser and administrator to the Portfolios. Subject to the supervision of the Board of Trustees, PIMCO is responsible for managing the investment activities of the Portfolios. PIMCO, in its role as administrator, is also responsible for managing the Portfolios’ business affairs and other administrative matters. Effective as of the close of business on September 5, 2014, PIMCO replaced its affiliate Allianz Global Investors Fund Management LLC as the investment adviser and administrator to the Portfolios. Prior thereto PIMCO was responsible for day-to-day portfolio management services it provided to each Portfolio as its sub-adviser.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to registered investment companies. PIMCO is a majority-owned indirect subsidiary of Allianz SE, a publicly traded European insurance and financial services company. As of December 31, 2023, PIMCO had approximately $1.86 trillion in assets under management.
Advisory and Other Fees
The Portfolios do not pay any fees, including an advisory or administrative fee, to PIMCO under the Investment Advisory Contract or the Supervision and Administrative Agreement between the Trust and PIMCO. However, each Portfolio is an integral part of “wrap-fee” programs, including those sponsored by investment advisers and broker-dealers unaffiliated with the Portfolio or PIMCO. Participants in these programs pay a “wrap” fee to the sponsor of the program. You should read carefully the wrap-fee brochure provided to you by the sponsor or your investment adviser for additional information on the “wrap” fee program. The brochure is required to include information about the fees charged to you by the sponsor and the fees paid by the sponsor to PIMCO and its affiliates. You pay no additional fees or expenses to purchase shares of the Portfolios.
Pursuant to an Expense Limitation Agreement between the Trust and PIMCO, PIMCO has contractually agreed to waive all fees and/or pay or reimburse all expenses of the Portfolios, including organizational and offering expenses and expenses associated with obtaining or maintaining a Legal Entity Identifier, but excluding any brokerage fees and commissions and other portfolio transaction expenses, costs, including interest expenses, of borrowing money or engaging in other types of leverage financing including, without limitation, through reverse repurchase agreements, tender option bonds, bank borrowings and credit facilities, fees and expenses of any underlying funds or other pooled vehicles in which the Portfolio invests, taxes, governmental fees, dividends and interest on short positions, and extraordinary expenses, including extraordinary legal expenses. The Expense Limitation Agreement will continue in effect, unless sooner terminated by the Trust’s Board of Trustees, for so long as PIMCO serves as the investment adviser to the Portfolios pursuant to the Investment Advisory Contract. See “Fees and Expenses of the Portfolio” for more information on these arrangements with respect to each Portfolio.
A discussion regarding the basis for the Board of Trustees’ approval of the Investment Advisory Contract is available in the Portfolios’ semi-annual report to shareholders for the period ended June 30, 2023.
Individual Portfolio Managers
The following individuals have or share primary responsibility for managing each of the noted Portfolios.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
FISH: Series C
FISH: Series M
David L. Braun
5/16
5/16
Managing Director, PIMCO. Mr. Braun joined PIMCO in 2009 and is head of the U.S. financial
institutions group and stable value portfolio management teams and a senior member of the
liability driven investment and U.S. core portfolio management teams.
FISH: Series TE
Kyle Christine
4/23
Senior Vice President, PIMCO. Mr. Christine is a senior vice president and municipal bond
portfolio manager in the Newport Beach office. He has previously served as a rotating
member of PIMCO's Americas portfolio committee. Prior to joining PIMCO in 2017, he was
an institutional high yield and taxable municipal bond trader at Morgan Stanley. He has
investment and financial services experience since 2013 and holds an undergraduate degree
from Union College (NY).
FISH: Series C
FISH: Series M
Mike Cudzil
10/22
10/22
Managing Director, PIMCO. Mr. Cudzil is a portfolio manager and mortgage specialist. Prior
to joining PIMCO in 2012, he worked as a managing director and head of pass-through
trading at Nomura.
FISH: Series TE
David Hammer
8/15
Managing Director, PIMCO. Mr. Hammer is a managing director in the Newport Beach office
and head of municipal bond portfolio management, with oversight of the firm’s municipal
investment grade, high yield, taxable, and separately managed accounts. He is the lead
portfolio manager on PIMCO’s municipal bond fund complex, including investment grade,
high yield, state-specific, closed-end funds, and interval funds. Prior to rejoining PIMCO in
2015, he was a managing director at Morgan Stanley, where he was head of municipal
trading, risk management, and research. He has investment experience since 2002 and holds
an undergraduate degree from Syracuse University.

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Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
FISH: Series R
Daniel He
12/19
Executive Vice President, PIMCO. Mr. He is a member of the liquid products group
specializing in real return and mortgage-backed securities. Prior to joining PIMCO in 2011,
he structured and traded derivative strategies for a global macro hedge fund. He previously
developed trading strategies at a hedge fund that focused on foreign exchange volatility. He
has investment experience since 2005 and holds an MBA from the University of Chicago
Booth School of Business. He also holds a master’s degree in financial engineering and an
undergraduate degree in computer science from the National University of Singapore.
FISH: Series R
Steve Rodosky
1/19
Managing Director, PIMCO. Mr. Rodosky is a portfolio manager for real return and U.S. long
duration strategies. He leads the rates liquid products team and also leads talent
management for portfolio management in the U.S. Prior to joining PIMCO in 2001, Mr.
Rodosky was vice president of institutional sales with Merrill Lynch. He has 29 years of
investment experience and holds a master's degree in financial markets from Illinois Institute
of Technology. He received an undergraduate degree from Villanova University.
FISH: Series LD
Jerome Schneider
12/13
Managing Director, PIMCO. Mr. Schneider joined PIMCO in 2008. Prior to joining PIMCO, he
served as Senior Managing Director with Bear Stearns, specializing in credit and
mortgage-related funding transactions. Mr. Schneider joined Bear Sterns in 1995.
FISH: Series C
FISH: Series M
Vinayak Seshasayee
10/22
10/22
Executive Vice President, PIMCO. Mr. Seshasayee is a generalist portfolio manager in the
New York office, leading Canadian portfolio management. He is a member of PIMCO’s
Americas portfolio committee. Previously, he was a portfolio manager on the MBS and
investment grade credit desks and a member of PIMCO’s diversified income portfolio
management team. Prior to joining PIMCO in 2013, he was a member of the fixed income
research group at Morgan Stanley. He has 13 years of investment experience and holds an
MBA from the University of Chicago Booth School of Business. He received an
undergraduate degree from the Indian Institute of Technology, Mumbai.
FISH: Series LD
Andrew Wittkop
12/13
Executive Vice President, PIMCO. Mr. Wittkop is a portfolio manager focusing on Treasury
bonds, agencies and interest rate derivatives. He previously worked on the real return desk.
Prior to that, he was a portfolio analyst with the global portfolio management team and a
product manager for absolute return strategies. He has investment experience since 2001
and holds an MBA from Stern School of Business at New York University and an
undergraduate degree from the University of California, Los Angeles.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers' compensation and the portfolio managers' ownership of shares of the Portfolios.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (“Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the SEC. Effective as of the close of business on September 5, 2014, PIMCO Investments LLC replaced Allianz Global Investors Distributors LLC as the distributor of the Portfolios.
Additional Information
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor, the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolios. Shareholders are not parties to or third-party beneficiaries of such service agreements.
Neither this prospectus, any summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or a Portfolio creates a contract between or among any shareholder of a Portfolio, on the one hand, and the Trust, a Portfolio, a service provider to the Trust or a Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to a Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or a Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to any Portfolio without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.

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Purchases and Redemptions
Eligible Investors and Opening an Account
Shares of the Portfolios may be purchased only by or on behalf of “wrap” account clients where PIMCO or Virtus Fund Advisers, LLC (each, as applicable, the “Wrap Program Adviser”) has an agreement to serve as investment adviser or sub-adviser to the account with the wrap program sponsor (typically a registered investment adviser, bank or broker-dealer) or directly with the client. A client agreement to open an account typically may be obtained by contacting the wrap program sponsor.
The Portfolios intend to redeem shares held by or on behalf of a shareholder who ceases to be an eligible investor as described above and each investor, by purchasing shares, agrees to any such redemption.
There are no maximum or minimum initial investment requirements imposed by the Portfolios. Minimum investment amounts for investing in a Portfolio may be imposed by wrap program sponsors, and can be found in the wrap-fee brochure provided to you by the wrap program sponsor or your investment adviser. The broker-dealer acting on behalf of an eligible client must submit a purchase or redemption order to the Portfolios’ transfer agent, SS&C Global Investor & Distribution Solutions, Inc., 330 West 9th Street, 5th Floor, Kansas City, Missouri 64105, either directly or through an appropriate clearing agency (e.g., the National Securities Clearing Corporation — Fund/SERV). The broker-dealer submitting an initial or subsequent order to purchase Portfolio shares must arrange to have federal funds wired to the transfer agent. Wiring instructions may be obtained by calling 1-800-927-4648.
Other Purchase Information Purchases of Portfolio shares will normally be made only in full shares, but may be made in fractional shares under certain circumstances. Certificates for shares will not be issued.
Each Portfolio reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order. Each Portfolio may do so in consultation with the Wrap Program Adviser.
The Trust typically does not offer or sell its shares to non-U.S. residents. For purposes of this policy, a U.S. resident is defined as an account with (i) a U.S. address of record and (ii) all account owners residing in the U.S. at the time of the sale.
Other Redemption Information
Redemption proceeds will ordinarily be sent by wire. Redemption proceeds will normally be wired within one to three business days after the redemption request, but may take up to seven days. Shareholders who are no longer eligible to invest in the Portfolios may receive their redemption proceeds by check. See “Eligible Investors and Opening an Account” above.
Redemptions of Portfolio shares may be made on any day the New York Stock Exchange (“NYSE”) is open, but may be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the applicable Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as
permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemptions or postpone payments for more than seven days, as permitted by law.
In order to meet redemption requests, the Portfolios typically expect to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolios) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolios reserve the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information.
It is highly unlikely that shares would ever be redeemed in kind. However, in consideration of the best interests of the remaining investors, and to the extent permitted by law, each Portfolio reserves the right to pay any redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. When shares are redeemed in kind, the investor should expect to incur transaction costs upon the disposition of the securities received in the distribution.
Calculation of Share Price and Redemption Payments
When Portfolio shares are purchased or redeemed, the price that is paid or received is equal to the net asset value (“NAV”) of the shares, without any sales charges or other fees. NAVs are ordinarily determined as of the close of regular trading on the New York Stock Exchange (normally 4:00 p.m., Eastern time) (the “NYSE Close”) on each day the New York Stock Exchange is open. See “How Portfolio Shares are Priced.”
On any day that the New York Stock Exchange (“NYSE”) closes earlier than 4:00 pm, Eastern time (scheduled or unscheduled), the Portfolio reserves the right to: (i) advance the time the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
In most cases, purchase and redemption orders are made based on instructions from the Wrap Program Adviser, in its capacity as investment adviser or sub-adviser to the applicable wrap account, to the broker-dealer who executes trades for the account. Purchases and redemption orders may also be made by wrap account sponsors or their affiliates from time to time. Purchase and redemption orders are

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processed at the NAV next calculated after the broker-dealer receives the order on behalf of the account. Orders received by the broker-dealer prior to the time a Portfolio’s NAV is determined on a business day will be processed at that day’s NAV, even if the order is received by the transfer agent after the Portfolio’s NAV has been calculated that day, as long as the order is received by the transfer agent prior to such time as agreed upon by the transfer agent and the broker-dealer.
The Portfolios do not calculate NAVs or process purchase or redemption orders on days when the NYSE is closed. If a purchase or redemption order is made on a day when the NYSE is closed, it will be processed on the next succeeding day when the NYSE is open (at the succeeding day’s NAV).
Market Timing Policy
In general, the practice of “market timing,” which includes short-term or excessive trading of mutual fund shares and other abusive trading practices, may have a detrimental effect on a mutual fund and its shareholders. Depending upon various factors such as the mutual fund’s size and the amount of its assets maintained in cash, market timing by fund shareholders may interfere with the efficient management of the fund’s portfolio, increase transaction costs and taxes, and harm the performance of the fund and its shareholders. Because the Portfolios are designed to be components of “wrap” accounts that also invest, at the direction of the applicable Wrap Program Adviser, in individual securities and other investments, Portfolio shares may be purchased or redeemed on a frequent basis for rebalancing purposes or in order to invest new monies (including through dividend reinvestment) or to accommodate reductions in account size. The Portfolios are managed in a manner that is consistent with their role in the “wrap” accounts. Because all purchase and redemption orders are initiated by the applicable Wrap Program Adviser, “wrap” account clients are not in a position to effect purchase and redemption orders and are, therefore, unable to directly trade in Portfolio shares. Accordingly, the Board of Trustees has not adopted a market timing policy for the Portfolios. However, each Portfolio reserves the right to refuse purchase orders.
How Portfolio Shares are Priced
The price of a Portfolio’s shares is based on the Portfolio’s NAV. The NAV of a Portfolio’s shares is determined by dividing the total value of a Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolios or their agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, each Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. Each Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is
closed on a day it would normally be open for business, each Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotations are readily available are valued at market value. A market quotation is readily available only when that quotation is a quoted price (unadjusted) in active markets for identical investments that the Portfolio can access at the measurement date, provided that a quotation will not be readily available if it is not reliable. Market value is generally determined on the basis of official closing prices or the last reported sales prices. The Portfolios will normally use pricing data for domestic equity securities received shortly after the NYSE Close and do not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Investments for which market quotations are not readily available are valued at fair value as determined in good faith pursuant to Rule 2a-5 under the 1940 Act. As a general principle, the fair value of a security or asset is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Pursuant to Rule 2a-5, the Board of Trustees has designated PIMCO as the valuation designee (“Valuation Designee”) for each Portfolio to perform the fair value determination relating to all Portfolio investments. PIMCO may carry out its designated responsibilities as Valuation Designee through various teams and committees. The Valuation Designee’s policies and procedures govern the Valuation Designee’s selection and application of methodologies for determining and calculating the fair value of portfolio investments. The Valuation Designee may value Portfolio securities for which market quotations are not readily available and other Portfolio assets utilizing inputs from pricing services, quotation reporting systems, valuation agents and other third-party sources (together, “Pricing Sources”). Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Sources using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Sources may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Sources. With respect to any portion of a Portfolio’s assets that

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are invested in one or more open-end management investment companies, other than exchange-traded funds (“ETFs”), a Portfolio’s NAV will be calculated based upon the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value. Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, a Portfolio may determine the fair value of investments based on information provided by Pricing Sources, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Valuation Designee may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. A Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, unless otherwise determined by the Valuation Designee, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in a Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans will generally be valued at the mean of bid/ask prices in the market for such loans, as provided by Pricing Sources. Senior secured floating rate loans for which vendor prices are not available will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Sources. As a result, the value of such investments and, in turn, the NAV of a Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that a Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Fair valuation may require subjective determinations about the value of a security. While the Trust’s and Valuation Designee's policies and procedures are intended to result in a calculation of a Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values accurately reflect the price that a Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by a Portfolio may differ from the value that would be realized if the securities were sold.
Portfolio Distributions
Each Portfolio distributes substantially all of its net investment income to shareholders in the form of dividends. Generally, you begin earning dividends on the shares the day after a Portfolio receives your purchase payment. Each Portfolio intends to declare dividends daily and distribute them monthly to shareholders of record on the last business day of the month.
In addition, each Portfolio distributes any net capital gains it earns from the sale of portfolio securities to shareholders investing in the Portfolio no less frequently than annually. Net short-term capital gains may be paid more frequently.
A Portfolio’s dividend and capital gain distributions will be paid only in cash. Dividends and capital gains will not be reinvested in additional Portfolio shares.
Tax Consequences
Treatment as RIC
This section summarizes some of the U.S. federal income tax consequences to U.S. persons of investing in the Portfolios; the consequences under other tax laws and to non-U.S. shareholders may differ. Shareholders should consult their tax advisors as to the possible application of federal, state, local or non-U.S. income tax laws. This summary is based on the Code, U.S. Treasury regulations, and other applicable authority, all as of the date of this prospectus. These authorities are subject to change by legislative or administrative action, possibly with retroactive effect. Please see the SAI for additional information regarding the tax aspects of investing in the Portfolios.
Each Portfolio has elected and intends each year to qualify and be eligible to be treated as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”). A regulated investment company is not subject to U.S. federal income tax at the corporate level on income and gains that are distributed to shareholders. A Portfolio’s failure to qualify as a regulated investment company would result in corporate-level taxation, thereby reducing the return on your investment.
Taxes on Portfolio Distributions
A shareholder subject to U.S. federal income tax will generally be subject to tax on Portfolio distributions, unless, in the case of FISH: Series TE, the distribution is properly reported as an “exempt-interest

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dividend.” For U.S. federal income tax purposes, Portfolio distributions other than exempt-interest dividends will generally be taxable to a shareholder as either ordinary income or capital gains.
Portfolio dividends consisting of distributions of investment income generally are taxable to shareholders as ordinary income. Federal taxes on Portfolio distributions of capital gains are determined by how long the Portfolio owned or is deemed to have owned the investments that generated the capital gains, rather than how long a shareholder has owned the shares. Distributions of net capital gains (that is, the excess of net long-term capital gains over net short-term capital losses, in each case determined with reference to any loss carryforwards) that are properly reported by a Portfolio as capital gain dividends generally will be treated as long-term capital gains includible in a shareholder’s net capital gains and taxed to individuals at reduced rates. The Portfolios do not expect a significant portion of their distributions to be treated as long-term capital gains. Distributions of net short-term capital gains in excess of net long-term capital losses generally will be taxable to you as ordinary income.
A Note on FISH: Series TE Distributions. Distributions to shareholders that FISH: Series TE properly reports to shareholders as “exempt-interest dividends” are generally not subject to U.S. federal income taxation, but may be subject to state and local taxes. In addition, a portion of FISH: Series TE distributions may be included in the computation of federal and state alternative minimum tax liability for individuals. FISH: Series TE may invest a portion of its assets in securities that generate income that is not exempt from U.S. federal income tax. Dividends attributable to taxable interest or capital gains will be subject to federal income tax.
The Code generally imposes a 3.8% Medicare contribution tax on the net investment income of certain individuals, trusts and estates to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends (other than exempt-interest dividends) paid by a Portfolio, including any capital gain dividends, and including net capital gains recognized on the sale, redemption or exchange of shares of a Portfolio. Shareholders are advised to consult their tax advisors regarding the possible implications of this additional tax on their investment in a Portfolio.
The ultimate tax characterization of a Portfolio’s distributions made in a taxable year cannot be determined finally until after the end of that taxable year. As a result, there is a possibility that a Portfolio may make total distributions during a taxable year in an amount that exceeds such Portfolio’s current and accumulated earnings and profits. In that case, the excess generally would be treated as return of capital and would reduce the shareholders’ tax basis in the applicable shares, with any amounts exceeding such basis treated as gain from the sale of such shares. A return of capital is not taxable, but it reduces a shareholder’s tax basis in the shares, thus reducing any loss or increasing any gain on a subsequent taxable disposition by the shareholder of the shares.
Portfolio distributions are taxable to shareholders as described above even if they are paid from income or gains earned by a Portfolio before a shareholder’s investment (and thus were included in the price the shareholder paid).
A Portfolio’s transactions in derivatives, short sales or similar transactions could affect the amount, timing and character of distributions from the Portfolio, and could increase the amount or accelerate the timing for payment of taxes payable by shareholders. A Portfolio’s investments in certain debt instruments could cause the Portfolio to recognize taxable income in excess of the cash generated by such investments (which may require the Portfolio to sell investments in order to make required distributions).
Income received by a Portfolio from sources within foreign countries may be subject to withholding and other taxes imposed by such countries, which will reduce the Portfolio’s return on those investments. If eligible, a Portfolio may elect to pass through to you a deduction or credit for foreign taxes. If the Portfolio so elects, shareholders will include in gross income from foreign sources their pro rata shares of such taxes, if any, paid by the Portfolio. There can be no assurance that a Portfolio will make such election, even if it is eligible to do so. If the Portfolio does not qualify for or does not make such election, shareholders will not be entitled separately to claim a credit or deduction with respect to foreign taxes paid by the Portfolio; in that case the foreign tax will nonetheless reduce the Portfolio’s taxable income. A Portfolio’s investments in non-U.S. securities (other than equity securities) or foreign currencies may increase or accelerate the Portfolio’s recognition of ordinary income and may affect the timing or amount of the Portfolio’s distributions.
Taxes When You Sell (Redeem) Your Shares
Any gain resulting from the sale or redemption of Portfolio shares generally will be taxable to shareholders as capital gains for U.S. federal income tax purposes.
Backup Withholding
Each Portfolio generally is required to withhold and remit to the U.S. Treasury a percentage of the taxable distributions and redemption proceeds paid to any shareholder who fails to properly furnish the Portfolio with a correct taxpayer identification number, who has under-reported dividend or interest income, or who fails to certify to the Portfolio that he, she or it is not subject to such withholding. The backup withholding rules may also apply to distributions that are properly reported as exempt-interest dividends.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolios identified under “Portfolio Summaries” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolios from time to time. Most of these securities and investment techniques described

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herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolios. As with any fund, investors in the Portfolios rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolios.
Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time, including for the same or similar instruments, are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies and/or portfolio management teams, similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different strategy or portfolio management team, the execution venue(s) used for a given strategy or Portfolio, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management. For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances. While such risks may apply to a Portfolio of any size, such risks are heightened in a Portfolio with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, a Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other portfolios, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale,
accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
FISH: Series C, FISH: Series M and FISH: Series LD seek maximum total return, and FISH: Series R seeks maximum real return, in each case consistent with preservation of capital and prudent investment management. The total return sought by FISH: Series C, FISH: Series M and FISH: Series LD consists of both income earned on investments and capital appreciation, if any, arising from increases in the market value of a Portfolio’s holdings. The real return sought by FISH: Series R equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. FISH: Series TE seeks high current income exempt from U.S. federal income tax consistent with prudent investment management, and total return/capital appreciation is a secondary objective. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for a Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy, analyzes credit and call risks; and uses other security selection techniques. The proportion of a Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors. In selecting investments for a Portfolio, PIMCO may use proprietary quantitative models that are developed and maintained by PIMCO, and which are subject to change over time without notice in PIMCO’s discretion.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.

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Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this Prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loans, including participations in and assignments thereof;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises;
obligations of international agencies or supranational entities; and
floating and variable rate debt instruments.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolios, to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond fund with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Conversely, the price of a bond fund with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are
affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of a Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities. The U.S. Government Securities in which a Portfolio may invest may pay fixed, floating, variable, or adjustable interest rates. Investments in zero-coupon securities generally require a Portfolio to accrue and distribute income not yet received. As a result, in order to generate cash to make the requisite distributions, the Portfolio may be required to sell securities in its portfolio that it would otherwise have continued to hold. Please see “Taxation” in the SAI for more information.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors ( i.e. , not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government.

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Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
Mortgage-Related and Other Asset-Backed Securities
Each Portfolio may invest in mortgage-related securities and in other asset-backed securities. FISH: Series M invests principally in these securities and may invest its assets without limit in these and other asset-backed securities. FISH: Series C and FISH: Series LD may also invest their assets without limit in these and other asset-backed securities. Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property. A to-be-announced (“TBA”) transaction is a method of trading mortgage-backed securities. In a TBA transaction, the buyer and seller agree upon general trade parameters such as agency, settlement date, par amount and price. The actual pools delivered generally are determined two days prior to the settlement date.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose a Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The value of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
FISH: Series C, FISH: Series M, FISH: Series R and FISH: Series LD may also invest in in any level of the capital structure of an issuer of mortgage-backed or asset-backed securities, including the equity or
“first loss” tranche, which may be referred to as subordinate mortgage-backed or asset-backed securities and interest-only mortgage-backed or asset-backed securities, subject to any other restrictions described in the Portfolios’ prospectus or SAI in effect from time to time. Subordinate mortgage-backed or asset-backed securities are paid interest only to the extent that there are funds available to make payments. To the extent the collateral pool includes a large percentage of delinquent loans, there is a risk that interest payment on subordinate mortgage-backed or asset-backed securities will not be fully paid. There are multiple tranches of mortgage-backed and asset-backed securities, offering investors various maturity and credit risk characteristics. Tranches are categorized as senior, mezzanine, and subordinated/equity or “first loss,” according to their degree of risk. The most senior tranche of a mortgage-backed or asset-backed security has the greatest collateralization and pays the lowest interest rate. If there are defaults or the collateral otherwise underperforms, scheduled payments to senior tranches take precedence over those of mezzanine tranches, and scheduled payments to mezzanine tranches take precedence over those to subordinated/equity tranches. Lower tranches represent lower degrees of credit quality and pay higher interest rates intended to compensate for the attendant risks. The return on the lower tranches is especially sensitive to the rate of defaults in the collateral pool. The lowest tranche (i.e. the “equity” or “residual” tranche) specifically receives the residual interest payments (i.e., money that is left over after the higher tranches have been paid and expenses of the issuing entities have been paid) rather than a fixed interest rate. The Portfolios expect that investments in subordinate mortgage-backed and other asset-backed securities will be subject to risks arising from delinquencies and foreclosures, thereby exposing its investment portfolio to potential losses. Subordinate securities of mortgage-backed and other asset-backed securities are also subject to greater credit risk than those mortgage-backed or other asset-backed securities that are more highly rated.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolios may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolios to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.

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One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on a Portfolio’s yield to maturity from these securities. FISH: Series C and FISH: Series M may not invest more than 40% of their net assets, and FISH: Series R may not invest more than 20% of its net assets, in any combination of interest only (“IO”), principal-only (“PO”) or inverse floating rate securities.
The Portfolios may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. Each Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in a Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Commercial Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Reinvestment
Each Portfolio may be subject to the risk that the returns of a Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. A Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio managers believe the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by a Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that a Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; contagion risk within a particular industry or sector; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, a Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. A Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Inflation-Indexed Bonds
FISH: Series R ordinarily expects to invest a substantial portion of its assets in inflation-indexed bonds. Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal

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inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal. TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market. Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus the Consumer Price Index. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation-indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds. The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Short-term increases in inflation may lead to a decline in value. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity. As a result, in order to generate cash to make the requisite distributions, a Portfolio may be required to sell securities in its portfolio (including when it is not advantageous to do so) that it would otherwise have continued to hold. Please see “Taxation” in the SAI for more information.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophe and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. Each Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other
securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Each Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. Residual interest bonds are a type of inverse floater. See “Municipal Bonds” below. FISH: Series C and FISH: Series M may not invest more than 40% of their net assets, and FISH: Series R may not invest more than 20% of its net assets, in any combination of IO, PO, or inverse floating rate securities.
When a Portfolio holds variable- or floating-rate securities, a decrease (or, in the case of inverse floating-rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value of the Portfolio’s shares. Certain of a Portfolio’s investments, including variable- and floating-rate securities, may require the Portfolio to accrue and distribute income not yet received. As a result, in order to generate cash to make the requisite distributions, the Portfolio may be required to sell securities in its portfolio that it would otherwise have continued to hold. Please see “Taxation” in the SAI for more information.
Foreign (Non-U.S.) Securities
Certain Portfolios may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. Certain Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or OTC. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the

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issuer of such money market instrument is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for FISH: Series C and FISH: Series M, which may invest in securities issued by foreign companies and governments of foreign countries, and FISH: Series C, FISH: Series M, FISH: Series R, and FISH: Series LD, each of which may invest its assets, without limit, in securities denominated in non-U.S. currencies and may invest without limit in U.S. dollar denominated securities of foreign issuers. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of the imposition of sanctions and other similar measures, nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries’ financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility.
Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or
uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers' financial reporting.
FISH: Series C, FISH: Series M, FISH: Series R and FISH: Series LD also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
FISH: Series C, FISH: Series M, FISH: Series R and FISH: Series LD may invest in Brady Bonds, which are securities created through the exchange of existing commercial bank loans to sovereign entities for new obligations in connection with a debt restructuring. Investments in Brady Bonds may be viewed as speculative. Brady Bonds acquired by a Portfolio may be subject to restructuring arrangements or to requests for new credit, which may cause a Portfolio to suffer a loss of interest or principal on any of its holdings of relevant Brady Bonds.
Emerging Market Securities. FISH: Series C, FISH: Series M and FISH: Series LD may invest without limit in securities and instruments that are economically tied to developing (or “emerging market”) countries. FISH: Series R may invest, subject to applicable law, without limit in investment grade sovereign debt denominated in the relevant country’s local currency with less than 1 year remaining to maturity (“short-term investment grade sovereign debt”), including short-term investment grade sovereign debt issued by emerging market issuers. FISH: Series R may invest up to 20% of its total assets in securities of issuers economically tied to “emerging market” countries other than investments in short-term investment grade sovereign debt issued by emerging market issuers, where as noted above there is no limit. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below.
With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market

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country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, FISH: Series C, FISH: Series M, FISH: Series R and FISH: Series LD emphasize countries with relatively low gross national product per capita and with the potential for rapid economic growth.
Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to the imposition of sanctions and other similar measures, price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by a Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less
governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal, custodial and share registration systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause a Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies, will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments or central banks, or by currency controls or political developments. Currencies in which the Portfolios’ assets are denominated may be devalued against the U.S. dollar, resulting in a loss to a Portfolio.
Foreign Currency Transactions. FISH: Series C, FISH: Series M, FISH: Series R and FISH: Series LD may engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces a Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of a Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict a Portfolio’s ability to enter into foreign currency transactions, force a Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. A Portfolio may enter into these contracts to

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hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. To the extent foreign exchange transactions for the Portfolios are directed to the Portfolios' custodian for execution, execution of such transactions may be better or worse than comparable transactions effected by other intermediaries. Suitable hedging transactions may not be available in all circumstances, and there can be no assurance that a Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for a Portfolio to benefit from favorable fluctuations in relevant foreign currencies. A Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated.
Redenomination. Uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has at times created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of a Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, a Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. A Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities.
There can be no assurance that if a Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw a Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense, or delay in, doing so.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to, the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. Certain Portfolios may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case a Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which a Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this Prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P, and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings, and an issuer’s current financial condition may be better or worse than a rating indicates. A Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by a Portfolio could receive a higher rating or a lower rating during the period in which they are held by a Portfolio.
PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality. A Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO's rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit quality, which could result in the Portfolio’s portfolio having a higher level of credit and/or high yield risk than PIMCO has estimated or desires for the Portfolio, and could negatively impact the Portfolio’s performance and/or returns. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of

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higher-quality fixed income securities. To the extent that a Portfolio invests in high yield and/ or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager’s creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and higher-rated securities.
Derivatives
Each Portfolio may, but is not required to, use derivatives and similar instruments (referred to collectively as “derivatives”) for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, real estate and other assets, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). Each Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies, and there is no assurance that any derivatives strategy used by a Portfolio will succeed. A description of these and other derivative instruments that the Portfolios may use are described under “Investment Objectives and Policies” in the SAI.
A Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on a Portfolio. For example, a small investment in a derivative instrument may have a significant impact on a Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. A Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. A Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolios.
Management Risk. Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Counterparty Risk (including Credit Risk). The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if a Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based. Counterparty risk also refers to the risks of having concentrated exposure to a counterparty.
Market and Portfolio Liquidity Risk. Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price. Liquidity risk also refers to the risk that a Portfolio may be required to hold additional cash or sell other investments in order to obtain cash to close out derivatives or meet the liquidity demands that derivatives can create to make payments of margin, collateral, or settlement payments to counterparties. A Portfolio may have to sell a security at a disadvantageous time or price to meet such obligations.
Leverage Risk. Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When a Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. Leveraging transactions pursued by the Portfolio may increase its duration and sensitivity to interest rate movements.
Lack of Availability. Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain a Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. There is no assurance that a Portfolio will engage in derivatives transactions at any time or from time to time. A Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk . In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolios offered in this prospectus may seek to achieve their investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance)

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of an index on a daily basis. However, the overall investment strategies of these Portfolios are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) a Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of a Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks. Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to a Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for a Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of a Portfolio’s derivative transactions, or impede the employment of a Portfolio’s derivatives strategies or adversely affect the Portfolios’ performance.
Other risks in using derivatives include the risk of mispricing and/or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to a Portfolio. Also, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the
exchange-traded fund is based because the fund’s return is net of fees and expenses. In addition, a Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates when distributed to shareholders) than if the Portfolio had not used such instruments.
Operational and Legal Risk. Using derivatives is also subject to operational and legal risks. Operational risk generally refers to risk related to potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls, and human error. Legal risk generally refers to insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
Each Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. A Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
The Portfolios may invest in “synthetic“ convertible securities. “Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. A Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities represent an equity interest in a company that generally entitles the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Some preferred securities also entitle their holders to receive additional liquidation proceeds on the same basis as holders of a company's common stock, and thus also represent an ownership interest in that company. Preferred securities may pay fixed or adjustable rates of return. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Preferred securities of smaller companies may be more vulnerable to adverse developments than preferred securities of larger companies.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
Each Portfolio may invest in convertible securities or equity securities.  While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, a Portfolio may consider convertible securities or equity securities to gain exposure to such investments. At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, a Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by a Portfolio at any given time upon sale thereof, a Portfolio may determine to hold such securities in its portfolio. Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by a Portfolio may go up or down, sometimes rapidly or unpredictably.
Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage, and reduced demand for the issuer’s goods or services.
Municipal Bonds
The amount of public information available about the municipal bonds held by a Portfolio is generally less than for corporate equities or bonds, and the investment performance of the Portfolio may therefore be more dependent on the abilities of PIMCO than would be a stock fund or taxable bond fund. The secondary market for municipal bonds, particularly the lower-rated bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds.
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rated bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing

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unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. Municipal securities may also have exposure to potential physical risks resulting from climate change, including extreme weather, flooding and fires. Climate risks, if they materialize, can adversely impact a municipal issuer’s financial plans in current or future years including, for example, the physical impairment of a facility or other source generating revenues backing a municipal issuer’s revenue bonds. As a result, the impact of climate risks could adversely impact the value of a Portfolio’s Municipal Bond investments. The types of Municipal Bonds in which the Portfolios may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, loans, mortgages, pre-refunded and escrowed to maturity Municipal Bonds and other debt instruments and pools of any of the foregoing. The Portfolios may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolios may also invest in securities issued by entities whose underlying assets are Municipal Bonds. The Portfolios (other than FISH: Series TE) do not expect to be eligible to pass through the tax-exempt character of interest paid on Municipal Bonds to their shareholders.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by a Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by a Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk. In addition, while a secondary market exists for pre-refunded Municipal Bonds, if a Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale. The interest on pre-funded bonds issued on or before December 31, 2017 is exempt from federal income tax; the interest on such bonds issued after December 31, 2017 is not exempt from federal income tax.
The Portfolios may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest
rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that a Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status. A Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond a Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. A Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
A Portfolio may invest in municipal securities (including taxable municipal securities) issued by Puerto Rico. A Portfolio that invests in municipal securities issued by Puerto Rico may be particularly affected by political, economic, regulatory or restructuring developments affecting the ability of Puerto Rican municipal issuers to pay interest or repay principal.
Municipal Project Housing-Related Risk
A Portfolio may invest in the bonds of projects focused on low-income, affordable or other housing developments and businesses located in low-income areas or invest in or originate loans that finance or are generally related to such projects. There are significant risks associated with the Portfolio’s investment in the bonds of these types of projects and loans related to such projects. There may be federal, state and local governmental regulatory restrictions on the operation, rental and transfer of these projects, such as the requirement that the owners of these affordable housing developments rent or sell certain residential units to persons or families of low or moderate income and that the amount of rent that may be charged for these units may be less than market rates. These restrictions may adversely affect economic performance relative to properties that are not subject to these restrictions. There are also no assurances that a project owner will be able to achieve and maintain sufficient rental income in order to pay all operating expenses and maintenance and repair costs of such a project and the debt service on the related bonds or loan on a timely basis. In the event that a project owner is unable to pay all such costs, expenses and debt service, a default on the related bonds or loan is likely to occur.
Loan Participations and Assignments
Each Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either

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PIMCO Managed Accounts Trust

of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and a Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If a Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Delayed Funding Loans and Revolving Credit Facilities
Each Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
Loans of Portfolio Securities
For the purpose of achieving income, each Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When a Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. A Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of a Portfolio. Cash collateral received by a Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. As a shareholder of an investment company or other pooled vehicle, a Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers. To the extent such cash collateral is invested in an affiliated money market or short-term mutual fund, such fees generally will not be waived, and PIMCO expects to select such an investment without considering or canvassing the universe of available unaffiliated investment companies. A Portfolio bears the risk of such investments.
Short Sales
Each Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose a Portfolio to the risk that it will be required to acquire, convert
or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. A short sale is ”against the box“ to the extent that a Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolios may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent a Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
When-Issued, Delayed Delivery and Forward Commitment Transactions
Each Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase or sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase a Portfolio’s overall investment exposure. Typically, no income accrues on securities a Portfolio has committed to purchase prior to the time delivery of the securities is made. When a Portfolio has sold a security on a when-issued, delayed-delivery or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, a Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed-delivery or forward commitment basis without owning the security, a Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Repurchase Agreements
Each Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, that agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price. Repurchase agreements may be or become illiquid. These events could also trigger adverse tax consequences for the Portfolio.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
Each Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by a Portfolio and its agreement to repurchase the instrument or a similar security at a specified time and price. A dollar roll is similar except that the

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Prospectus

counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for a Portfolio.
A Portfolio also may borrow money for investment purposes (including, with respect to FISH: Series R, FISH: Series TE and FISH: Series LD, borrowing money from certain affiliated funds pursuant to the Portfolios’ inter-fund lending program, as described more fully under “Investment Restrictions - Other Information Regarding Investment Restrictions” in the SAI) subject to any policies of the Portfolio currently described in this prospectus or in the Portfolio’s SAI.
Event-Linked Exposure
Each Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, a Portfolio may lose a portion of or its entire principal invested in the bond or notional amount on a swap. Event-linked exposures often provide for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposures may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposures may also be subject to liquidity risk.
Portfolio Turnover
The length of time a Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by a Portfolio is known as “portfolio turnover.” When the portfolio managers deem it appropriate and particularly during periods of volatile market movements, a Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover ( e.g. , an annual rate greater than 100% of the average value of a Portfolio’s portfolio) involves correspondingly greater expenses to a Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect a Portfolio’s performance. Please see a Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolios that were operational during the last fiscal year.
Illiquid Investments
Each Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments, and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e. , securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid ( i.e. , classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include a possible decline in the value of (or income generated by) the real estate, variations in rental income, fluctuations in occupancy levels, changes in the availability or terms of mortgages and other financing that may render the sale or refinancing of properties difficult or unattractive, loss to casualty or condemnation, and changes in local and general economic conditions. Additionally, an investment in REITs, and investing in the real estate market generally, is subject to risks involved with supply and demand, including reduced demand for properties or real estate-related services, reduced demand for commercial and office space as well as increased maintenance or tenant improvement costs to

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convert properties for other uses, default risk of tenants and borrowers, the financial condition of tenants, buyers and sellers, and the inability to re-lease space on attractive terms or to obtain mortgage financing on a timely basis or at all, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Real estate securities may have limited diversification and, therefore, tend to be subject to risks inherent in operating and financing a limited number of projects. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Investment in Other Investment Companies
Each Portfolio may invest in securities of other investment companies (including those advised by PIMCO), such as open-end or closed-end management investment companies, including exchange-traded funds and business development companies, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. A Portfolio may invest in other investment companies to gain broad market or sector exposure or for cash management purposes, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, a Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers. To the extent a Portfolio invests in other investment companies that are advised by PIMCO, PIMCO expects to select such investments without considering or canvassing the universe of available unaffiliated investment companies.
Each Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act, and the rules and regulations thereunder and any exemptive relief therefrom, each Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio. SEC regulations concerning investments by registered investment companies in the securities of other registered investment companies may, among
other things, limit investment flexibility and could affect the Portfolios’ ability to utilize the Central Funds. This could adversely impact the Portfolios’ investment strategies and operations. The “Investment Objectives and Policies -Regulatory Risk” section in the SAI discusses these changes in further detail.
Temporary Defensive Positions
For temporary defensive purposes, each Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When a Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of a Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in a Portfolio’s custody account. Cash assets are generally not income-generating and would impact a Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of each Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolios may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations and Alternative Means of Gaining Exposure
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. A Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. Unless otherwise indicated, references to assets in the percentage limitations on portfolio investments refer to total assets. Unless otherwise stated, if a Portfolio is described as investing in a particular type of security or other instrument, either generally or subject to a minimum investment percentage, the Portfolio may make such investments either directly or by gaining exposure through indirect means, such as depositary receipts, derivatives, placement warrants or other structured products. Such exposure may be achieved through a combination of multiple instruments or through a combination of one or more investment instruments and cash or cash equivalents.
Operational Risk
An investment in a Portfolio, like any fund, can involve operational risks arising from factors such as processing errors, human errors, inadequate or failed internal or external processes, failure in systems and technology, changes in personnel and errors caused by third-party service providers. The occurrence of any of these failures, errors or breaches could result in a loss of information, regulatory scrutiny, reputational damage or other events, any of which could have a significant adverse effect on a Portfolio. The occurrence of any of these

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Prospectus

failures, errors or breaches could result in a loss of information, regulatory scrutiny, reputational damage or other events, any of which could have a significant adverse effect on a Portfolio. While the Portfolios seek to minimize such events through controls and oversight, there may still be failures that could cause losses to a Portfolio.
Market Disruptions Risk
The Portfolios are subject to investment and operational risks associated with financial, economic and other global market developments and disruptions, including those arising from war, terrorism, market manipulation, government interventions, defaults and shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/ environmental disasters, which can all negatively impact the securities markets and cause a Portfolio to lose value. These events can also impair the technology and other operational systems upon which a Portfolio’s service providers, including PIMCO as the Portfolios’ investment adviser, rely, and could otherwise disrupt a Portfolio’s service providers’ ability to fulfill their obligations to the Portfolios.
Other Investments and Techniques
The Portfolios may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this Prospectus. These securities and techniques may subject the Portfolios to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this Prospectus and about additional securities and techniques that may be used by the Portfolios.
Geopolitical Conflicts
The occurrence of geopolitical conflicts, war or terrorist activities could have adverse impacts on markets in various and unpredictable ways. For example, following Russia’s large-scale invasion of Ukraine in February 2022, Russia, and other countries, persons and entities that were viewed as having provided material aid to Russia’s aggression against Ukraine, became the subject of economic sanctions and import and export controls imposed by countries throughout the world, including the United States. Such measures have had and may continue to have an adverse effect on the Russian, Belarusian and other securities and economies. The extent, duration and impact of geopolitical conflicts and related market impacts are difficult to ascertain, but could be significant and could have significant adverse effects on regional and global economies and the markets for certain securities and commodities, such as oil and natural gas, as well as other sectors, and on a Portfolio’s investments.
Cyber Security
As the use of technology, including cloud-based technology, has become more prevalent in the course of business, the Portfolios have become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events from
outside threat actors or internal resources that may, among other things, cause a Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to a Portfolio’s digital information systems ( e.g. , through “hacking” or malicious software coding), and may come from multiple sources, including outside attacks such as denial-of-service attacks ( i.e. , efforts to make network services unavailable to intended users) or cyber extortion, including exfiltration of data held for ransom and/or “ransomware” attacks that render systems inoperable until ransom is paid, or insider actions ( e.g. , intentionally or unintentionally harmful act of PIMCO personnel). In addition, cyber security breaches involving a Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, vendors, suppliers, distributors and other third parties), trading counterparties or issuers in which a Portfolio invests can also subject a Portfolio to many of the same risks associated with direct cyber security breaches or extortion of company data. PIMCO's use of cloud-based service providers could heighten or change these risks. Cyber security failures or breaches may result in financial losses to a Portfolio and its shareholders. For example, cyber security failures or breaches involving trading counterparties or issuers in which a Portfolio invests could adversely impact such counterparties or issuers and cause a Portfolio’s investments to lose value. In addition, work-from-home arrangements by a Portfolio, the Investment Manager or their service providers could increase all of the above risks, create additional data and information accessibility concerns, and make a Portfolio, PIMCO or its service providers susceptible to operational disruptions, any of which could adversely impact their operations.
These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with a Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; third party claims in litigation; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolios have established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios do not directly control the cyber security systems of issuers in which a Portfolio may invest, trading counterparties or third party service providers to the Portfolios. Such entities have experienced cyber attacks and other attempts to gain unauthorized access to systems from time to time, and there is no guarantee that efforts to prevent or mitigate the effects of such attacks or other attempts to gain

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unauthorized access will be successful. There is also a risk that cyber security breaches may not be detected. The Portfolios and their shareholders may suffer losses as a result of a cyber security breach related to the Portfolios, their service providers, trading counterparties or the issuers in which a Portfolio invests.
Regulatory Changes Risk
Financial entities, such as investment companies and investment advisers, are generally subject to extensive government regulation and intervention. Government regulation and/or intervention may change the way the Portfolio is regulated, affect the expenses incurred directly by the Portfolio and the value of its investments, and limit and/or preclude the Portfolio’s ability to achieve its investment objective. Government regulation may change frequently and may have significant adverse consequences. The Portfolio and the investment adviser have historically been eligible for exemptions from certain regulations. However, there is no assurance that the Portfolio and the investment adviser will continue to be eligible for such exemptions. Actions by governmental entities may also impact certain instruments in which the Portfolio invests.
Moreover, government regulation may have unpredictable and unintended effects. Legislative or regulatory actions to address perceived liquidity or other issues in fixed income markets generally, or in particular markets such as the municipal securities market, may alter or impair the Portfolio’s ability to pursue its investment objective or utilize certain investment strategies and techniques.

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PIMCO Managed Accounts Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the financial performance of FISH: Series C, FISH: Series LD, FISH: Series M, FISH: Series R and FISH: Series TE for the last five fiscal years. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in a particular Portfolio (assuming reinvestment of all dividends and distributions). This information has been audited by PricewaterhouseCoopers LLP, whose report, along with each Portfolio’s financial statements, are included in the Trust’s annual report to shareholders. The annual report is available free of charge by calling the Trust at the phone number on the back of this prospectus. The annual report is also available for download free of charge on the Trust’s website at pimco.com.
 
 
Investment Operations
Less Distributions (c)
 
 
 
 
Selected Per Share Data for
the Year Ended^:
Net Asset Value
Beginning of
Year (a)
Net Investment
Income (Loss) (b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gains
Tax Basis
Return of
Capital
Total
Series C
 
 
 
 
 
 
 
 
12/31/2023
$ 8.54
$0.40
$ 0.29
$ 0.69
$(0.39)
$ 0.00
$ 0.00
$(0.39)
12/31/2022
10.77
0.33
(2.12)
(1.79)
(0.44)
0.00
0.00
(0.44)
12/31/2021
11.08
0.34
(0.31)
0.03
(0.34)
0.00
0.00
(0.34)
12/31/2020
10.43
0.34
0.66
1.00
(0.35)
0.00
0.00
(0.35)
12/31/2019
9.94
0.38
0.52
0.90
(0.41)
0.00
0.00
(0.41)
Series LD
 
 
 
 
 
 
 
 
12/31/2023
$ 8.59
$ 0.34
$ 0.17
$ 0.51
$ (0.17)
$ 0.00
$ (0.12)
$ (0.29)
12/31/2022
9.41
0.25
(0.77)
(0.52)
(0.26)
(0.04)
0.00
(0.30)
12/31/2021
9.62
0.28
(0.24)
0.04
(0.25)
0.00
0.00
(0.25)
12/31/2020
9.40
0.35
0.23
0.58
(0.36)
0.00
0.00
(0.36)
12/31/2019
9.40
0.36
0.00
0.36
(0.36)
0.00
0.00
(0.36)
Series M
 
 
 
 
 
 
 
 
12/31/2023
$ 8.35
$0.47
$ 0.26
$ 0.73
$(0.48)
$ 0.00
$ 0.00
$(0.48)
12/31/2022
10.33
0.42
(1.95)
(1.53)
(0.45)
0.00
0.00
(0.45)
12/31/2021
10.68
0.42
(0.26)
0.16
(0.42)
(0.09)
0.00
(0.51)
12/31/2020
10.48
0.41
0.53
0.94
(0.41)
(0.33)
0.00
(0.74)
12/31/2019
10.14
0.47
0.37
0.84
(0.50)
0.00
0.00
(0.50)
Series R
 
 
 
 
 
 
 
 
12/31/2023
$ 7.94
$ 0.19
$ 0.05
$ 0.24
$ (0.04)
$ 0.00
$ (0.15)
$ (0.19)
12/31/2022
10.79
0.81
(2.59)
(1.78)
(1.07)
0.00
0.00
(1.07)
12/31/2021
10.74
0.72
0.02
0.74
(0.69)
0.00
0.00
(0.69)
12/31/2020
9.40
0.22
1.33
1.55
(0.21)
0.00
0.00
(0.21)
12/31/2019
8.68
0.26
0.70
0.96
(0.24)
0.00
0.00
(0.24)
Series TE
 
 
 
 
 
 
 
 
12/31/2023
$ 9.25
$0.47
$ 0.41
$ 0.88
$(0.46)
$ 0.00
$ 0.00
$(0.46)
12/31/2022
10.71
0.41
(1.47)
(1.06)
(0.40)
0.00
0.00
(0.40)
12/31/2021
10.76
0.38
(0.06)
0.32
(0.37)
0.00
0.00
(0.37)
12/31/2020
10.39
0.36
0.37
0.73
(0.36)
0.00
0.00
(0.36)
12/31/2019
9.94
0.38
0.45
0.83
(0.38)
0.00
0.00
(0.38)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolios.
(b)
Per share amounts based on average number of shares outstanding during the year.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolios. Additionally, excludes initial sales charges and contingent deferred sales charges.
(e)
The calculation assumes that all income dividends and capital gain distributions, if any, have been reinvested. Total return does not reflect broker commissions or “wrap fee” charges. Total investment return for a period of less than one year is not annualized.
(f)
The financial statements reflect the fact that no investment management fees or expenses are incurred by the Portfolios. The Portfolios are an integral part of “wrap-fee” programs sponsored by investment advisers and/or broker-dealers unaffiliated with the Portfolios and PIMCO. Participants in these programs pay a “wrap fee” to the sponsor of the program.

60  Prospectus | PIMCO Managed Accounts Trust

Prospectus

 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year (a)
Total
Return (d)(e)
Net Assets End of
Year (000s)
Expenses (f)
Expenses
Excluding Waivers (f)
Expenses Excluding
Interest Expense (f)
Expenses Excluding
Interest Expense
and Waivers (f)
Net Investment
Income (Loss)
Portfolio
Turnover Rate
$ 8.84
8.34
%
$ 1,282,061
0.03
%
0.03
%
0.00
%
0.00
%
4.69
%
571
%
8.54
(16.74
)
1,155,312
0.15
0.15
0.00
0.00
3.58
308
10.77
0.34
1,540,072
0.02
0.02
0.00
0.00
3.10
282
11.08
9.77
1,585,611
0.03
0.03
0.00
0.00
3.18
562
10.43
9.18
1,434,199
0.21
0.21
0.00
0.00
3.72
533
$ 8.81
6.07
%
$ 73,673
2.31
%
2.31
%
0.00
%
0.00
%
3.90
%
192
%
8.59
(5.53
)
74,964
1.57
1.57
0.00
0.00
2.75
43
9.41
0.38
122,608
0.23
0.23
0.00
0.00
2.94
97
9.62
6.28
108,895
0.66
0.66
0.00
0.00
3.63
69
9.40
3.85
79,806
2.98
2.98
0.00
0.00
3.82
88
$ 8.60
8.99
%
$ 1,279,095
0.04
%
0.04
%
0.00
%
0.00
%
5.62
%
569
%
8.35
(14.99
)
1,147,875
0.01
0.01
0.00
0.00
4.58
495
10.33
1.45
1,520,815
0.01
0.01
0.00
0.00
3.97
468
10.68
9.12
1,562,661
0.02
0.02
0.00
0.00
3.80
635
10.48
8.40
1,442,194
0.06
0.06
0.00
0.00
4.47
543
$ 7.99
3.05
%
$ 163,970
3.31
%
3.31
%
0.00
%
0.00
%
2.45
%
223
%
7.94
(17.22
)
216,389
0.87
0.87
0.00
0.00
8.88
93
10.79
7.09
259,263
0.05
0.05
0.00
0.00
6.71
162
10.74
16.58
157,315
0.26
0.26
0.00
0.00
2.13
295
9.40
11.10
130,421
1.35
1.35
0.00
0.00
2.80
357
$ 9.67
9.74
%
$ 61,959
0.06
%
0.06
%
0.00
%
0.00
%
5.05
%
56
%
9.25
(9.91
)
69,553
0.07
0.07
0.00
0.00
4.29
67
10.71
3.04
88,310
0.02
0.02
0.00
0.00
3.50
20
10.76
7.19
91,321
0.04
0.04
0.00
0.00
3.47
57
10.39
8.42
87,423
0.08
0.08
0.00
0.00
3.69
31

May 1, 2024 | Prospectus 61

PIMCO Managed Accounts Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securities are those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securities are those rated in one of the four highest rating categories, or, if unrated, deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”), are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of eleven months or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) or similar programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim ( e.g. , senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Managed Accounts Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued ( e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located ( e.g. , KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term debt obligations relative to other domestic issuers or issuances.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term debt obligations relative to other domestic issuers or issuances.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term debt obligations relative to other domestic issuers or issuances.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term debt obligations relative to other domestic issuers or issuances.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

May 1, 2024 | Prospectus   A-2

PIMCO Managed Accounts Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within the next five business days in the absence of a stated grace period or within the earlier of the stated grace period or the next 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Managed Accounts Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation, and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

May 1, 2024 | Prospectus   A-4

PIMCO Managed Accounts Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*: This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
i: This suffix was used for issues in which the credit factors, terms, or both that determine the likelihood of receipt of payment of interest are different from the credit factors, terms, or both that determine the likelihood of receipt of principal on the obligation. The 'i' suffix indicated that the rating addressed the interest portion of the obligation only. The 'i' suffix was always used in conjunction with the 'p' suffix, which addresses likelihood of receipt of principal. For example, a rated obligation could have been assigned a rating of 'AAApNRi' indicating that the principal portion was rated 'AAA' and the interest portion of the obligation was not rated.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary noncredit-related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.

A-5  Prospectus | PIMCO Managed Accounts Trust

Prospectus

B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met; however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Very low margin for safety. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.
A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch’s opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch’s opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.

May 1, 2024 | Prospectus   A-6

PIMCO Managed Accounts Trust

Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention (a long-term rating can also be used to rate an issue with short maturity). Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.
F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Managed Accounts Trust

INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 1100 Main Street, Suite 400, Kansas City, MO 64105
TRANSFER AGENT
SS&C Global Investor & Distribution Solutions, Inc., 430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Ropes & Gray LLP, Prudential Tower, 800 Boylston Street, Boston, MA 02199-3600

PIMCO Managed Accounts Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolios. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected each Portfolio’s performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolios. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolios by calling the Trust at 1-800-927-4648 or by writing to:
PIMCO Managed Accounts Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of a Portfolio may be obtained by calling 1-800-927-4648.
As permitted by regulations adopted by the Securities and Exchange Commission, paper copies of the Portfolio’s annual and semi-annual shareholder reports from your financial intermediary, such as a broker-dealer or bank, which offers the Portfolio will no longer be sent by mail, unless you specifically request paper copies from the Portfolio or from your financial intermediary. Instead, the shareholder reports will be made available on a website, and your financial intermediary will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your financial intermediary. Paper copies of the Portfolio’s shareholder reports are required to be provided free of charge by the financial intermediary.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s web site at www.sec.gov . You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to [email protected]. You can also visit our web site at pimco.com for additional information about the Portfolios, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-09721
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