2024-02-295-1Multi-AffiliateStatutoryProspectus

Gateway Equity Call Premium Fund

Investment Goal

The Fund seeks total return with less risk than U.S. equity markets.

Fund Fees & Expenses

The following table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in this table. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the Natixis Funds Complex. More information about these and other discounts is available from your financial professional and in the section “How Sales Charges Are Calculated” on page 61 of the Prospectus, in Appendix A to the Prospectus and on page 111 in the section “Reduced Sales Charges” of the Statement of Additional Information (“SAI”).

Shareholder Fees


(fees paid directly from your investment)	Class A	Class C	Class N	Class T	Class Y
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	5.75%	None	None	2.50%	None
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)	None*	1.00%	None	None	None
Redemption fees	None	None	None	None	None

*	A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.

Annual Fund Operating Expenses


(expenses that you pay each year as a percentage of the value of your investment)	Class A	Class C	Class N	Class T	Class Y
Management fees	0.58%	0.58%	0.58%	0.58%	0.58%
Distribution and/or service (12b-1) fees	0.25%	1.00%	0.00%	0.25%	0.00%
Other expenses	0.26%	0.26%	0.70%	0.26%¹	0.26%
Total annual fund operating expenses	1.09%	1.84%	1.28%	1.09%	0.84%
Fee waiver and/or expense reimbursement²^,³	0.16%	0.16%	0.65%	0.16%	0.16%
Total annual fund operating expenses after fee waiver and/or expense reimbursement	0.93%	1.68%	0.63%	0.93%	0.68%

1	Other expenses for Class T shares are estimated for the current fiscal year.

Gateway Investment Advisers, LLC (“Gateway” or the “Adviser”) has given a binding contractual undertaking to the Fund to limit the amount of the Fund’s total annual fund operating expenses to 0.93%, 1.68%, 0.63%, 0.93% and 0.68% of the Fund’s average daily net assets for Class A, Class C, Class N, Class T and Class Y shares, respectively, exclusive of brokerage expenses, interest expense, taxes, acquired fund fees and expenses, organizational and extraordinary expenses, such as litigation and indemnification expenses. This undertaking is in effect through April 30, 2025 and may be terminated before then only with the consent of the Fund’s Board of Trustees. The Adviser will be permitted to recover, on a class-by-class basis, management fees waived and/or expenses reimbursed to the extent that expenses in later periods fall below both (1) the class’ applicable expense limitation at the time such amounts were waived/reimbursed and (2) the class’ current applicable expense limitation. The Fund will not be obligated to repay any such waived/reimbursed fees and expenses more than one year after the end of the fiscal year in which the fees or expenses were waived/reimbursed.

Natixis Advisors, LLC (“Natixis Advisors”) has given a binding contractual undertaking to the Fund to reimburse any and all transfer agency expenses for Class N shares. This undertaking is in effect through April 30, 2025 and may be terminated before then only with the consent of the Fund’s Board of Trustees.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods (except where indicated). The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same except that the example is based on the Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement assuming that such waiver and/or reimbursement will only be in place through the date noted above and on the Total Annual Fund Operating Expenses for the remaining periods. The example for Class C shares for the ten-year period reflects the conversion to Class A shares after eight years. The example does not take into account brokerage commissions and other fees to financial intermediaries that you may pay on your purchases and sales of shares of the Fund. Although your actual costs may be higher or lower, based on these assumptions your costs would be:


If shares are redeemed:	1 year		3 years		5 years		10 years
Class A	$	664	$	887	$	1,127	$	1,814
Class C	$	271	$	563	$	981	$	1,949
Class N	$	64	$	342	$	640	$	1,488
Class T	$	343	$	572	$	821	$	1,531
Class Y	$	69	$	252	$	450	$	1,022


If shares are not redeemed:	1 year		3 years		5 years		10 years
Class C	$	171	$	563	$	981	$	1,949

Portfolio Turnover

The Fund pays transaction costs, such as commissions, 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 for you if your Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During its most recently ended fiscal year, the Fund’s portfolio turnover rate was 32% of the average value of its portfolio.

Investments, Risks and Performance

Principal Investment Strategies

Under normal circumstances, the Fund will invest at least 80% of its net assets (plus any borrowings made for investment purposes) in equity securities. Equity securities purchased by the Fund may include the following U.S. exchange-listed securities: common stocks; American Depositary Receipts (“ADRs”), which are securities issued by a U.S. bank that represent interests in foreign equity securities; and interests in real estate investment trusts (“REITs”). The Fund ordinarily invests in a broadly diversified equity portfolio, while also writing (selling) index call options with an aggregate notional value approximately equal to the market value of the equity portfolio. Writing index call options is intended to reduce the Fund’s volatility and provide steady cash flow. Cash flow from call option writing is intended to be an important source of the Fund’s return, although the Fund’s option writing activity reduces the Fund’s ability to profit from increases in the value of its equity portfolio. The combination of a diversified stock portfolio and the steady cash flow from the sale of index call options is intended to moderate the volatility of returns relative to an all-equity portfolio. The Fund may invest in companies with small, medium or large market capitalizations.

The Fund’s combination of a broadly diversified portfolio of common stocks and written index call options is similar to the components of the Cboe S&P 500 BuyWrite Index (the “BXM^SM”). The BXM^SM is a passive total return index based on (1) buying an S&P 500^® stock index portfolio, and (2) writing (selling) the near-term S&P 500^® Index “covered” call option. The Fund’s more flexible, active option management approach creates the potential for it to achieve higher long-term returns than the BXM^SM while exhibiting a similar level of volatility, as defined by standard deviation of returns. The similarities between the BXM^SM and the Fund’s equity investment strategy are expected to result in the Fund exhibiting a positive correlation to the broad U.S. equity markets similar to that exhibited by the BXM^SM.

With its core investment in equities, the Fund is intended to be significantly less vulnerable to fluctuations in value caused by interest rate volatility, a risk factor present in both fixed-income investments and “hybrid investments” (blends of equity and fixed-income securities). Through the use of index options, the Fund intends that its risk management strategy will reduce the volatility inherent in equity investments while also allowing for more participation in equity returns than hybrid investments. Thus, the Fund seeks to provide an efficient trade-off between risk and reward, where risk is characterized by volatility or fluctuations in value over time.

Purchasing Stocks

The Fund invests in a diversified stock portfolio, generally consisting of approximately 200 to 400 stocks (including ADRs and REITs), designed to support the Fund’s index option-based risk management strategy as efficiently as possible while seeking to enhance the Fund’s after-tax total return. The Adviser uses a multifactor quantitative model to construct the stock portfolio. The model evaluates U.S.-exchange-traded equities that meet the criteria and constraints established by the Adviser. Generally, the Adviser tries to minimize the difference between the performance of the Fund’s stock portfolio and the performance of the index or indices underlying the Fund’s option strategies while also considering other factors, such as predicted dividend yield. The Adviser monitors this difference and other factors, and rebalances and adjusts the stock portfolio from time to time, by purchasing and selling stocks. To the extent consistent with the Fund’s investment goal, the Adviser may also sell stocks to realize capital losses in an effort to minimize any required capital gain distributions. The Adviser expects the portfolio to generally represent the broad U.S. equity market.

Writing Index Call Options

The Fund continuously writes index call options, typically on broad-based securities market indices, with an aggregate notional value approximately equal to the market value of its broadly diversified stock portfolio. As the seller of the index call option, the Fund receives cash (the “premium”) from the purchaser. The purchaser of an index call option has the right to any appreciation in the value of the index over a fixed price (the “exercise price”) on a certain date in the

future (the “expiration date”). If the purchaser does not exercise the option, the Fund retains the premium. If the purchaser exercises the option, the Fund pays the purchaser the difference between the value of the index and the exercise price of the option. The premium, the exercise price and the value of the index determine the gain or loss realized by the Fund as the seller of the index call option. The Fund can also repurchase the call option prior to the expiration date, ending its obligation. In such a case, the difference between the cost of repurchasing the option and the premium received will determine the gain or loss realized by the Fund.

Other Investments

The Fund may invest in foreign securities traded in U.S. markets (through ADRs or stocks traded in U.S. dollars). The Fund may enter into repurchase agreements and/or hold cash and cash equivalents.

Principal Investment Risks

The principal risks of investing in the Fund are summarized below. The Fund does not represent a complete investment program. You may lose money by investing in the Fund.

Fund shares are not bank deposits and are not guaranteed, endorsed or insured by the Federal Deposit Insurance Corporation or any other government agency, and are subject to investment risks, including possible loss of the principal invested.

The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund’s portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

Management Risk: A strategy used by the Fund’s portfolio managers may fail to produce the intended result.

Call Options Risk: The value of the Fund’s positions in index options will fluctuate in response to changes in the value of the underlying index. Writing index call options limits the opportunity to profit from an increase in the market value of stocks in exchange for up-front cash at the time of selling the call option. Unusual market conditions or the lack of a ready market for any particular option at a specific time may reduce the effectiveness of the Fund’s option-based risk management strategy, and for these and other reasons the Fund’s option strategy may not reduce the Fund’s volatility to the extent desired.

Equity Securities Risk: The value of the Fund’s investments in equity securities could be subject to unpredictable declines in the value of individual securities and periods of below-average performance in individual securities or in the equity market as a whole. In the event an issuer is liquidated or declares bankruptcy, the claims of owners of the issuer’s bonds generally take precedence over the claims of those who own preferred stock or common stock. Securities of real estate-related companies and REITs in which the Fund may invest may be considered equity securities, thus subjecting the Fund to the risks of investing in equity securities generally. Small- and mid-capitalization and emerging growth companies may be subject to more abrupt price movements, limited markets and less liquidity than larger, more established companies, which could adversely affect the value of the Fund’s equity portfolio.

Correlation Risk: The Fund’s ability to manage the volatility of its equity portfolio by writing index options depends on the correlation between the returns of the equity portfolio and those of the index on which the Fund’s index options are written. Accordingly, the effectiveness of the Fund’s index option-based risk management strategy may be reduced to the extent the performance of the Fund’s equity portfolio does not correlate to that of the indices underlying its option positions.

Market/Issuer Risk: The market value of the Fund’s investments will move up and down, sometimes rapidly and unpredictably, based upon overall market and economic conditions, as well as a number of reasons that directly relate to the issuers of the Fund’s investments, such as management performance, financial condition and demand for the issuers’ goods and services.

Cybersecurity and Technology Risk: The Fund, its service providers, and other market participants increasingly depend on complex information technology and communications systems, which are subject to a number of different threats and risks that could adversely affect the Fund and its shareholders. Cybersecurity and other operational and technology issues may result in financial losses to the Fund and its shareholders.

Foreign Securities Risk: Investments in foreign securities may be subject to greater political, economic, environmental, credit/counterparty and information risks. The Fund’s investments in foreign securities also are subject to foreign currency fluctuations and other foreign currency-related risks. Foreign securities may be subject to higher volatility than U.S. securities, varying degrees of regulation and limited liquidity.

Large Investor Risk: Ownership of shares of the Fund may be concentrated in one or a few large investors. Such investors may redeem shares in large quantities or on a frequent basis. Redemptions by a large investor can affect the performance of the Fund, may increase realized capital gains, including short-term capital gains taxable as ordinary income, may accelerate the realization of taxable income to shareholders and may increase transaction costs. These transactions potentially limit the use of any capital loss carryforwards and certain other losses to offset future realized capital gains (if any). Such transactions may also increase the Fund’s expenses.

REITs Risk: Investments in the real estate industry, including REITs, are particularly sensitive to economic downturns and are sensitive to factors such as changes in real estate values, property taxes and tax laws, interest rates, cash flow of underlying real estate assets, occupancy rates, government regulations affecting zoning, land use and rents and the management skill and creditworthiness of the issuer. Companies in the real estate industry also may be subject to liabilities under environmental and hazardous waste laws. In addition, the value of a REIT is affected by changes in the value of the properties owned by the REIT or mortgage loans held by the REIT. REITs are also subject to default and prepayment risk. Many REITs are highly leveraged, increasing their risk. The

Fund will indirectly bear its proportionate share of expenses, including management fees, paid by each REIT in which it invests in addition to the expenses of the Fund.

Risk/Return Bar Chart and Table

The bar chart and table shown below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year-to-year and by showing how the Fund’s average annual returns for the one-year, five-year, life-of-fund and life-of-class periods (as applicable) compare to those of a broad-based securities market index that reflects the performance of the overall market applicable to the Fund and an additional index that represents the market sectors in which the Fund primarily invests. Performance for Class C shares includes the automatic conversion to Class A shares after eight years, where applicable. The Fund’s past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information is available online at im.natixis.com and/or by calling the Fund toll-free at 800-225-5478.

The chart does not reflect any sales charge that you may be required to pay when you buy or redeem the Fund’s shares. A sales charge will reduce your return. To the extent that a class of shares was subject to the waiver or reimbursement of certain expenses during a period, had such expenses not been waived or reimbursed during the period, total returns would have been lower.

Total Returns for Class Y Shares


	Highest Quarterly Return: Second Quarter 2020, 11.74% Lowest Quarterly Return: First Quarter 2020, -15.92%


Average Annual Total Returns
(for the periods ended December 31, 2023)	Past 1 Year	Past 5 Years	Life of Fund (9/30/14)	Life of Class N (5/1/17)
Class Y - Return Before Taxes	17.59%	9.47%	7.03%	-
Return After Taxes on Distributions	17.32%	9.23%	6.76%	-
Return After Taxes on Distributions and Sale of Fund Shares	10.59%	7.46%	5.61%	-
Class A - Return Before Taxes	10.61%	7.92%	6.08%	-
Class C - Return Before Taxes	15.44%	8.38%	6.08%	-
Class N - Return Before Taxes	17.74%	9.51%	-	7.33%
Class T - Return Before Taxes	14.45%	8.66%	6.47%	-
S&P 500^® Index¹	26.29%	15.69%	12.05%	12.88%
CBOE S&P 500 BuyWrite Index (BXM)	11.82%	6.08%	5.32%	4.91%

Effective May 1, 2024, the Fund’s primary broad-based performance index changed to the S&P 500® Index. The S&P 500® Index is a broad-based securities market index that represents the overall market applicable to the Fund. The Fund will retain CBOE S&P 500 BuyWrite Index (BXM) as its additional benchmark for performance comparison.

The Fund did not have Class T shares outstanding during the periods shown above. The returns of Class T shares would have been substantially similar to the returns of the Fund’s other share classes because they would have been invested in the same portfolio of securities and would only differ to the extent the other share classes did not have the same expenses. Performance of Class T shares shown above is that of Class A shares, which have the same expenses as Class T shares, restated to reflect the different sales load applicable to Class T shares.

After-tax returns are calculated using the historical highest 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 those shown. After-tax returns shown are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans, qualified plans, education savings accounts, such as 529 plans, or individual retirement accounts. The after-tax returns are shown for only one class of the Fund. After-tax returns for the other classes of the Fund will vary. Index performance reflects no deduction for fees, expenses or taxes.

Management

Investment Adviser

Gateway

Portfolio Managers

Daniel M. Ashcraft, CFA^®, Vice President and Portfolio Manager of the Adviser, has served as co-portfolio manager of the Fund since 2014.

Michael T. Buckius, CFA^®, President, Chief Executive Officer and Chief Investment Officer of the Adviser, has served as co-portfolio manager of the Fund since 2014.

Kenneth H. Toft, CFA^®, Senior Vice President and Portfolio Manager of the Adviser, has served as co-portfolio manager of the Fund since 2014.

Mitchell J. Trotta, CFA^®, Portfolio Manager of the Adviser, has served as co-portfolio manager of the Fund since 2021.

Purchase and Sale of Fund Shares

Class A and C Shares

The following chart shows the investment minimums for various types of accounts:


Type of Account	Minimum Initial Purchase
Any account other than those listed below	$2,500
For shareholders participating in Natixis Funds’ Automatic Investment Plan	$1,000
For Traditional IRA, Roth IRA, Rollover IRA, SEP-IRA and Keogh plans	$1,000

There is no subsequent investment minimum for these shares. There is no initial investment minimum for:

•	Fee Based Programs (such as wrap accounts) where an advisory fee is paid to the broker-dealer or other financial intermediary. Please consult your financial representative to determine if your fee based program is subject to additional or different conditions or fees.

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Clients of a Registered Investment Adviser where the Registered Investment Adviser receives an advisory, management or consulting fee.

The minimum investment requirements for Class A shares may be waived or lowered for investments effected through certain financial intermediaries that have entered into special arrangements with Natixis Distribution, LLC (the “Distributor”). Consult your financial intermediary for additional information regarding the minimum investment requirement applicable to your investment.

Class N Shares

Class N shares of the Fund are subject to a $1,000,000 initial investment minimum. This minimum applies to Fee Based Programs and accounts (such as wrap accounts) where an advisory fee is paid to the broker-dealer or other financial intermediary. There is no subsequent investment minimum for these shares. There is no initial investment minimum for:

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Sub-accounts held within an omnibus account, where the omnibus account has at least $1,000,000.

•	Funds of funds that are distributed by the Distributor.

In its sole discretion, the Distributor may waive the investment minimum requirement for accounts as to which the Distributor reasonably believes will have enough assets to exceed the investment minimum requirement within a relatively short period of time following the establishment date of such accounts in Class N. The Distributor and the Fund, at any time, reserve the right to liquidate these accounts or any other account that does not meet the eligibility requirements of this class.

Class T Shares

Class T shares of the Fund are not currently available for purchase.

Class T shares of the Fund may only be purchased by investors who are investing through an authorized third party, such as a broker-dealer or other financial intermediary, that has entered into a selling agreement with the Distributor. Investors may not hold Class T shares directly with the Fund. Class T shares are subject to a minimum initial investment of $2,500. There is no subsequent investment minimum for these shares. Not all financial intermediaries make Class T shares available to their clients.

Class Y Shares

Class Y shares of the Fund are generally subject to a minimum initial investment of $100,000. There is no subsequent investment minimum for these shares. There is no minimum initial investment for:

•	Fee Based Programs (such as wrap accounts) where an advisory fee is paid to the broker-dealer or other financial intermediary. Please consult your financial representative to determine if your fee based program is subject to additional or different conditions or fees.

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Certain Individual Retirement Accounts if the amounts invested represent rollover distributions from investments by any of the retirement plans invested in the Fund.

•	Clients of a Registered Investment Adviser where the Registered Investment Adviser receives an advisory, management or consulting fee.

•

Fund Trustees, former Fund trustees, employees of affiliates of the Natixis Funds and other individuals who are affiliated with any Natixis Fund (this also applies to any spouse, parents, children, siblings, grandparents, grandchildren and in-laws of those mentioned) and Natixis affiliate employee benefit plans.

At the discretion of Natixis Advisors, clients of Natixis Advisors and its affiliates may purchase Class Y shares of the Fund below the stated minimums.

Due to operational limitations at your financial intermediary, certain fee based programs, retirement plans, individual retirement accounts and accounts of registered investment advisers may be subject to the investment minimums described above.

The Fund’s shares are available for purchase and are redeemable on any business day through your investment dealer, directly from the Fund by writing to the Fund at Natixis Funds, P.O. Box 219579, Kansas City, MO 64121-9579, by exchange, by wire, by internet at im.natixis.com (certain restrictions may apply), through the Automated Clearing House system, or, in the case of redemptions, by telephone at 800-225-5478 or by the Systematic Withdrawal Plan.

Tax Information

Fund distributions are generally taxable to you as ordinary income or capital gains, except for distributions to retirement plans and other investors that qualify for tax-advantaged treatment under U.S. federal income tax law generally. Investments through such tax-advantaged plans will generally be taxed only upon withdrawal of monies from the tax-advantaged arrangement.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and its related companies may pay the intermediary for the sale of the Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

Gateway Fund

Investment Goal

The Fund seeks to capture the majority of the returns associated with equity market investments, while exposing investors to less risk than other equity investments.

Fund Fees & Expenses

Shareholder Fees


(fees paid directly from your investment)	Class A	Class C	Class N	Class T	Class Y
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	5.75%	None	None	2.50%	None
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)	None*	1.00%	None	None	None
Redemption fees	None	None	None	None	None

*	A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.

Annual Fund Operating Expenses


(expenses that you pay each year as a percentage of the value of your investment)	Class A	Class C	Class N	Class T	Class Y
Management fees	0.59%	0.59%	0.59%	0.59%	0.59%
Distribution and/or service (12b-1) fees	0.25%	1.00%	0.00%	0.25%	0.00%
Other expenses	0.14%	0.14%	0.07%	0.14%¹	0.14%
Total annual fund operating expenses	0.98%	1.73%	0.66%	0.98%	0.73%
Fee waiver and/or expense reimbursement²	0.04%	0.03%	0.01%	0.04%	0.03%
Total annual fund operating expenses after fee waiver and/or expense reimbursement	0.94%	1.70%	0.65%	0.94%	0.70%

1	Other expenses for Class T shares are estimated for the current fiscal year.

Gateway Investment Advisers, LLC (“Gateway” or the “Adviser”) has given a binding contractual undertaking to the Fund to limit the amount of the Fund’s total annual fund operating expenses to 0.94%, 1.70%, 0.65%, 0.94% and 0.70% of the Fund’s average daily net assets for Class A, Class C, Class N, Class T and Class Y shares, respectively, exclusive of brokerage expenses, interest expense, taxes, acquired fund fees and expenses, organizational and extraordinary expenses, such as litigation and indemnification expenses. This undertaking is in effect through April 30, 2025 and may be terminated before then only with the consent of the Fund’s Board of Trustees. The Adviser will be permitted to recover, on a class-by-class basis, management fees waived and/or expenses reimbursed to the extent that expenses in later periods fall below both (1) the class’ applicable expense limitation at the time such amounts were waived/reimbursed and (2) the class’ current applicable expense limitation. The Fund will not be obligated to repay any such waived/reimbursed fees and expenses more than one year after the end of the fiscal year in which the fees or expenses were waived/reimbursed.

Example


If shares are redeemed:	1 year		3 years		5 years		10 years
Class A	$	665	$	865	$	1,082	$	1,704


If shares are redeemed:	1 year		3 years		5 years		10 years
Class C	$	273	$	542	$	936	$	1,840
Class N	$	66	$	210	$	367	$	822
Class T	$	344	$	550	$	774	$	1,418
Class Y	$	72	$	230	$	403	$	904


If shares are not redeemed:	1 year		3 years		5 years		10 years
Class C	$	173	$	542	$	936	$	1,840

Portfolio Turnover

Investments, Risks and Performance

Principal Investment Strategies

Under normal circumstances, the Fund invests in a broadly diversified portfolio of common stocks, while also selling index call options and purchasing index put options. Writing index call options is intended to reduce the Fund’s volatility, provides steady cash flow and is an important source of the Fund’s return, although it also reduces the Fund’s ability to profit from increases in the value of its equity portfolio. The Fund also buys index put options, which can protect the Fund from a significant market decline that may occur over a short period of time. The value of an index put option generally increases as the prices of the stocks constituting the index decrease, and decreases as those stocks increase in price. From time to time, the Fund may reduce its holdings of put options, resulting in an increased exposure to a market decline. The combination of the diversified stock portfolio, the steady cash flow from the sale of index call options and the downside protection from index put options is intended to provide the Fund with the majority of the returns associated with equity market investments while exposing investors to less risk than other equity investments. The Fund may invest in companies with small, medium or large market capitalizations. Equity securities purchased by the Fund may include U.S. exchange-listed common stocks, American Depositary Receipts (“ADRs”), which are securities issued by a U.S. bank that represent interests in foreign equity securities, and interests in real estate investment trusts (“REITs”).

The Fund strives not only for the majority of the returns associated with equity market investments, but also for returns in excess of those available from other investments comparable in volatility. Because, as described above, the Fund writes index call options and purchases index put options in addition to investing in equity securities, the Fund’s historical volatility has been closer to intermediate- to long-term fixed-income investments (intermediate-term are those with approximately five-year maturities and long-term are those with maturities of ten or more years) and hybrid investments (blends of equity and short-term fixed-income securities) than to equity investments. With its core investment in equities, the Fund is significantly less vulnerable to fluctuations in value caused by interest rate volatility, a risk factor present in both fixed-income investments and “hybrid investments” (blends of equity and short-term fixed-income), although the Fund expects to generally have lower long-term returns than a fund consisting solely of equity securities. Through the use of index options, the Fund intends that its risk management strategy will reduce the volatility inherent in equity investments while also allowing for more participation in equity returns than hybrid investments. Thus, the Fund seeks to provide an efficient trade-off between risk and reward where risk is characterized by volatility or fluctuations in value over time.

Purchasing Stocks

The Fund invests in a diversified stock portfolio, generally consisting of approximately 200 to 400 stocks, designed to support the Fund’s index option based risk management strategy as efficiently as possible while seeking to enhance the Fund’s after tax total return. The Adviser uses a multifactor quantitative model to construct the stock portfolio. The model evaluates U.S.-exchange-traded equities that meet criteria and constraints established by the Adviser. Generally, the Adviser tries to minimize the difference between the performance of the stock portfolio and that of the index or indices underlying the Fund’s option strategies while also considering other factors, such as predicted dividend yield. The Adviser monitors this difference and the other factors, and rebalances and adjusts the stock portfolio from time to time, by purchasing and selling stocks. To the extent consistent with the Fund’s investment goal, the Adviser may also sell stocks to realize capital losses in an effort to minimize any required capital gain distributions. The Adviser expects the portfolio to generally represent the broad U.S. equity market.

Writing Index Call Options

The Fund continuously writes index call options, typically on broad-based securities market indices, on the full value of its broadly diversified stock portfolio. As the seller of the index call option, the Fund receives cash (the “premium”) from the purchaser. The purchaser of an index call option has the right to any appreciation in the value of the index over a fixed price (the “exercise price”) on a certain date in the future (the “expiration date”). If the purchaser does not exercise the option, the Fund retains the premium. If the purchaser exercises the option, the Fund pays the purchaser the difference between the value of the index and the exercise price of the option. The premium, the exercise price and the value of the index determine the gain or loss realized by the Fund as the

seller of the index call option. The Fund can also repurchase the call option prior to the expiration date, ending its obligation. In this case, the difference between the cost of repurchasing the option and the premium received will determine the gain or loss realized by the Fund.

Purchasing Index Put Options

The Fund may buy index put options in an attempt to protect the Fund from a significant market decline that may occur over a short period of time. The value of an index put option generally increases as stock prices (and the value of the index) decrease and decreases as those stocks (and the index) increase in price.

Other Investments

The Fund may invest in foreign securities traded in U.S. markets (through ADRs or stocks traded in U.S. dollars). The Fund may enter into repurchase agreements and/or hold cash and cash equivalents.

Principal Investment Risks

The principal risks of investing in the Fund are summarized below. The Fund does not represent a complete investment program. You may lose money by investing in the Fund.

Management Risk: A strategy used by the Fund’s portfolio managers may fail to produce the intended result.

Options Risk: The value of the Fund’s positions in index options will fluctuate in response to changes in the value of the underlying index. Writing index call options limits the opportunity to profit from an increase in the market value of stocks in exchange for up-front cash at the time of selling the call option. The Fund also risks losing all or part of the cash paid for purchasing index put options. Unusual market conditions or the lack of a ready market for any particular option at a specific time may reduce the effectiveness of the Fund’s option strategies, and for these and other reasons the Fund’s option strategies may not reduce the Fund’s volatility to the extent desired.

Correlation Risk: The Fund’s ability to manage the volatility of its equity portfolio by writing index options depends on the correlation between the returns of the equity portfolio and those of the index on which the Fund’s index options are written. Accordingly, the effectiveness of the Fund’s index option-based risk management strategy may be reduced if the performance of the Fund’s equity portfolio does not correlate to that of the indices underlying its option positions.

Risk/Return Bar Chart and Table

The bar chart and table shown below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year-to-year and by showing how the Fund’s average annual returns for the one-year, five-year, ten-year and life-of-class periods (as applicable) compare to those of two broad measures of market performance. Performance for Class C shares includes the automatic conversion to Class A shares after eight years, where applicable. The Fund’s past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information is available online at im.natixis.com and/or by calling the Fund toll-free at 800-225-5478.

Total Returns for Class Y Shares


	Highest Quarterly Return: Second Quarter 2020, 8.36% Lowest Quarterly Return: First Quarter 2020, -10.01%


Average Annual Total Returns
(for the periods ended December 31, 2023)	Past 1 Year	Past 5 Years	Past 10 Years	Life of Class N (5/1/17)
Class Y - Return Before Taxes	14.70%	6.07%	4.72%	-
Return After Taxes on Distributions	14.44%	5.82%	4.36%	-
Return After Taxes on Distributions and Sale of Fund Shares	8.87%	4.72%	3.66%	-
Class A - Return Before Taxes	7.85%	4.57%	3.85%	-
Class C - Return Before Taxes	12.56%	5.02%	3.83%	-
Class N - Return Before Taxes	14.75%	6.13%	-	4.80%
Class T - Return Before Taxes	11.58%	5.28%	4.20%	-
S&P 500^® Index	26.29%	15.69%	12.03%	12.88%
Bloomberg U.S. Aggregate Bond Index	5.53%	1.10%	1.81%	1.14%

Management

Investment Adviser

Gateway

Portfolio Managers

Daniel M. Ashcraft, CFA^®, Vice President and Portfolio Manager of the Adviser, has served as co-portfolio manager of the Fund since 2016.

Michael T. Buckius, CFA^®, President, Chief Executive Officer and Chief Investment Officer of the Adviser, has served as co-portfolio manager of the Fund since 2008.

Kenneth H. Toft, CFA^®, Senior Vice President and Portfolio Manager of the Adviser, has served as co-portfolio manager of the Fund since 2013.

Mitchell J. Trotta, CFA^®, Portfolio Manager of the Adviser, has served as co-portfolio manager of the Fund since 2021.

Purchase and Sale of Fund Shares

Class A and C Shares

The following chart shows the investment minimums for various types of accounts:


Type of Account	Minimum Initial Purchase
Any account other than those listed below	$2,500
For shareholders participating in Natixis Funds’ Automatic Investment Plan	$1,000
For Traditional IRA, Roth IRA, Rollover IRA, SEP-IRA and Keogh plans	$1,000

There is no subsequent investment minimum for these shares. There is no initial investment minimum for:

•	Fee Based Programs (such as wrap accounts) where an advisory fee is paid to the broker-dealer or other financial intermediary. Please consult your financial representative to determine if your fee based program is subject to additional or different conditions or fees.

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Clients of a Registered Investment Adviser where the Registered Investment Adviser receives an advisory, management or consulting fee.

Class N Shares

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Sub-accounts held within an omnibus account, where the omnibus account has at least $1,000,000.

•	Funds of funds that are distributed by the Distributor.

Class T Shares

Class T shares of the Fund are not currently available for purchase.

Class Y Shares

Class Y shares of the Fund are generally subject to a minimum initial investment of $100,000. There is no subsequent investment minimum for these shares. There is no minimum initial investment for:

•	Fee Based Programs (such as wrap accounts) where an advisory fee is paid to the broker-dealer or other financial intermediary. Please consult your financial representative to determine if your fee based program is subject to additional or different conditions or fees.

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Certain Individual Retirement Accounts if the amounts invested represent rollover distributions from investments by any of the retirement plans invested in the Fund.

•	Clients of a Registered Investment Adviser where the Registered Investment Adviser receives an advisory, management or consulting fee.

•

At the discretion of Natixis Advisors, LLC (“Natixis Advisors”), clients of Natixis Advisors and its affiliates may purchase Class Y shares of the Fund below the stated minimums.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Mirova Global Green Bond Fund

Investment Goal

The Fund seeks to provide total return, through a combination of capital appreciation and current income, by investing in green bonds.

Fund Fees & Expenses

The following table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in this table. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in the Natixis Funds Complex. More information about these and other discounts is available from your financial professional and in the section “How Sales Charges Are Calculated” on page 61 of the Prospectus, in Appendix A to the Prospectus and on page 111 in the section “Reduced Sales Charges” of the Statement of Additional Information (“SAI”).

Shareholder Fees


(fees paid directly from your investment)	Class A	Class N	Class Y
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	4.25%	None	None
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)	None*	None	None
Redemption fees	None	None	None

*	A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.

Annual Fund Operating Expenses


(expenses that you pay each year as a percentage of the value of your investment)	Class A	Class N	Class Y
Management fees	0.50%	0.50%	0.50%
Distribution and/or service (12b-1) fees	0.25%	0.00%	0.00%
Other expenses	0.66%	0.58%	0.66%
Total annual fund operating expenses	1.41%	1.08%	1.16%
Fee waiver and/or expense reimbursement¹^,²	0.48%	0.46%	0.48%
Total annual fund operating expenses after fee waiver and/or expense reimbursement	0.93%	0.62%	0.68%

Mirova US LLC (“Mirova US” or the “Adviser”) has given a binding contractual undertaking to the Fund to limit the amount of the Fund’s total annual fund operating expenses to 0.90%, 0.60% and 0.65% of the Fund’s average daily net assets for Class A, Class N and Class Y shares, respectively, exclusive of brokerage expenses, interest expense, taxes, acquired fund fees and expenses, organizational and extraordinary expenses, such as litigation and indemnification expenses. This undertaking is in effect through April 30, 2025 and may be terminated before then only with the consent of the Fund’s Board of Trustees. The Adviser will be permitted to recover, on a class-by-class basis, management fees waived and/or expenses reimbursed to the extent that expenses in later periods fall below both (1) the class’ applicable expense limitation at the time such amounts were waived/reimbursed and (2) the class’ current applicable expense limitation. The Fund will not be obligated to repay any such waived/reimbursed fees and expenses more than one year after the end of the fiscal year in which the fees or expenses were waived/reimbursed.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods (except where indicated). The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same except that the example is based on the Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement assuming that such waiver and/or reimbursement will only be in place through the date noted above and on the Total Annual Fund Operating Expenses for the remaining periods. The example does not take into account brokerage commissions and other fees to financial intermediaries that you may pay on your purchases and sales of shares of the Fund. Although your actual costs may be higher or lower, based on these assumptions your costs would be:


If shares are redeemed:	1 year		3 years		5 years		10 years
Class A	$	516	$	807	$	1,120	$	2,004
Class N	$	63	$	298	$	551	$	1,276
Class Y	$	69	$	321	$	592	$	1,366

Portfolio Turnover

Investments, Risks and Performance

Principal Investment Strategies

Under normal circumstances, the Fund will invest at least 80% of its net assets (plus any borrowings made for investment purposes) in “green bonds.” “Green bonds” are bonds and notes all of the proceeds of which are used to finance projects which the Adviser believes will have a positive environmental impact. The Fund invests in securities of issuers located in no fewer than three countries, which may include the U.S. Under normal circumstances, the Fund will invest at least 40% of its assets in securities of issuers located outside the U.S. and the Fund may invest up to 20% of its assets in securities of issuers located in emerging markets. The Adviser considers an issuer to be located outside the U.S. if its head office is located outside the U.S. Emerging markets are economies that the Adviser believes are not generally recognized to be fully developed markets, as measured by gross national income, financial market infrastructure, market capitalization and/or other factors. The Fund may invest up to 20% of its assets, at the time of purchase, in securities rated below investment grade (i.e., none of the three major ratings agencies (Moody’s Investors Services, Inc., Fitch Investor Services, Inc. or S&P Global Ratings) have rated the securities in one of their top four ratings categories) (commonly known as “junk bonds”), or, if unrated, securities determined by the Adviser to be of comparable quality. The Fund may invest in bonds of any maturity and expects that under normal circumstances the modified duration of its portfolio will range between 0 and 10 years. This flexibility is intended to allow the portfolio managers to reposition the Fund to take advantage of significant interest rate movements. Performance is expected to derive primarily from security selection and duration is not expected to be a major source of excess return relative to the benchmark.

The Fund primarily invests in fixed-income securities issued by companies, banks, supranational entities, development banks, agencies, regions and governments. In deciding which securities to buy and sell, the Adviser selects securities based on their financial valuation profile and an analysis of the global environmental, social and governance (“ESG”) impact of the issuer or the projects funded with the securities. The Adviser applies a Minimum Standards Policy, as described further in the “More About Goals and Strategies” section below, which sets forth criteria for specific exclusions that the Adviser will consider as part of its ESG analysis. Following the evaluation of a security, the portfolio managers value the security based, among other factors, on what they believe is a fair spread for the issue relative to comparable government securities, as well as historical and expected default and recovery rates. The portfolio managers will re-evaluate and possibly sell a security if there is a deterioration of its ESG quality and/or financial rating, among other reasons.

Green bonds are usually issued to finance specific projects intended to generate an environmental benefit while offering potential market return in the same manner as other “conventional” fixed income securities. Beyond fundamental security analysis, the Adviser independently analyzes each green bond it selects for the Fund along the following lines:

•	Use of Proceeds: legal documentation specifies that proceeds will be used to finance or refinance projects with a positive environmental impact, such as projects relating to climate change, preservation of resources, pollution prevention or mitigation and biodiversity.

•

Impact on Sustainable Opportunity: quality of the environmental impact of the project is analyzed. Five evaluation levels have been defined with respect to the positive environmental impact: High, Moderate, Low, Negligible and Negative. Only issues that the Adviser believes will have a High, Moderate or Low positive environmental impact can qualify.

•	Risk Evaluation: an analysis of the general practices of the issuer and of the management of the environmental and social risks during the life cycle of the projects.

•	Reporting: issuer should provide regular reports on the use of proceeds. This reporting will also be used to reevaluate all other aspects of the Adviser’s analysis as described above.

To be considered eligible for investment, the Adviser will consider the characteristics of the project(s) underlying the green bonds. In particular, the Adviser will consider (i) whether the bond’s stated use of proceed aims at financing projects with an environmental objective; (ii) management of environmental and social risks linked to the projects underlying the bond; and (ii) the alignment of the underlying projects with the issuers’ overall energy transition strategy. To the extent a security’s status changes such that it longer meets this exception from exclusion under the Minimum Standards Policy, the Fund shall take steps to divest its holdings within a reasonable period of time. Because the Fund’s divestment of such investments may not be immediate, the Fund could be invested temporarily in investments that do meet the qualification for exclusion and are not otherwise excepted therefrom. This screening criteria may be updated periodically.

The Adviser monitors developments in the global green bond market and may revise the above criteria in the future.

In connection with its principal investment strategies, the Fund may also invest in securities issued pursuant to Rule 144A under the Securities Act of 1933 (“Rule 144A securities”), municipal securities, mortgage-related and asset-backed securities, debt-linked and equity-linked securities, hybrid instruments and futures, forwards and foreign currency transactions for hedging and investment purposes. Except as provided above or as required by applicable law, the Fund is not limited in the percentage of its assets that it may invest in these instruments. The Adviser generally attempts to hedge the Fund’s foreign currency risk, though there is no guarantee its attempts to hedge all foreign currency risk will be successful.

Principal Investment Risks

The principal risks of investing in the Fund are summarized below. The Fund does not represent a complete investment program. You may lose money by investing in the Fund.

Below Investment Grade Fixed-Income Securities Risk: The Fund’s investments in below investment grade fixed-income securities, also known as “junk bonds,” may be subject to greater risks than other fixed-income securities, including being subject to greater levels of interest rate risk, credit/counterparty risk (including a greater risk of default) and liquidity risk. The ability of the issuer to make principal and interest payments is predominantly speculative for below investment grade fixed-income securities.

Emerging Markets Risk: In addition to the risks of investing in foreign investments generally, emerging markets investments are subject to greater risks arising from political or economic instability, war, nationalization or confiscatory taxation, currency exchange or repatriation restrictions, sanctions by other countries (such as the United States or the European Union), new or inconsistent government treatment of or restrictions on issuers and instruments, and an issuer’s unwillingness or inability to make dividend, principal or interest payments on its securities. Emerging markets companies may be smaller and have shorter operating histories than companies in developed markets.

ESG Investing Risk: The Fund’s ESG investment approach could cause the Fund to perform differently compared to funds that do not have such an approach or compared to the market as a whole. The Fund’s application of ESG-related considerations may affect the Fund’s exposure to certain issuers, industries, sectors, style factors or other characteristics and may impact the relative performance of the Fund—positively or negatively—depending on the relative performance of such investments. Excluding stocks that do not meet the ESG standards (as determined by the Adviser) results in a smaller universe of investments in which the Fund may invest, which may exacerbate this risk. In addition, certain green bonds may be dependent on government incentives and subsidies and lack of political support for the financing of projects with a positive environmental impact could negatively impact the performance of the Fund. Views on what constitutes “ESG investing,” and therefore what investments are appropriate for a fund that has an ESG investment approach, may differ by fund, adviser and investor. In evaluating an investment, a portfolio manager may be reliant upon information and data that may turn out to be incomplete, inaccurate or unavailable, which may negatively impact the portfolio manager’s assessment of an issuer’s ESG performance or the Fund’s performance generally. There is no guarantee that the Adviser’s efforts to select investments based on ESG practices will be successful.

Credit/Counterparty Risk: Credit/counterparty risk is the risk that the issuer or guarantor of a fixed-income security, or the counterparty to a derivative or other transaction, will be unable or unwilling to make timely payments of interest or principal or to otherwise honor its obligations. As a result, the Fund may sustain losses or be unable or delayed in its ability to realize gains. The Fund will be subject to credit/counterparty risk with respect to the counterparties to its derivatives transactions. This risk will be heightened to the extent the Fund enters into derivative transactions with a single counterparty (or affiliated counterparties that are part of the same organization), causing the Fund to have significant exposure to such counterparty. Many of the protections afforded to participants on organized exchanges and clearing houses, such as the performance guarantee given by a central clearing house, are not available in connection with over-the-counter (“OTC”) derivatives transactions, such as foreign currency transactions. For centrally cleared derivatives, such as cleared swaps, futures and many options, the primary credit/counterparty risk is the creditworthiness of the Fund’s clearing broker and the central clearing house itself.

Currency Risk: Fluctuations in the exchange rates between different currencies may negatively affect an investment. The Fund may be subject to currency risk because it may invest in currency-related instruments and may invest in securities or other instruments denominated in, or that generate income denominated in, foreign currencies. The Fund may elect not to hedge currency risk, or may hedge such risk imperfectly, which may cause the Fund to incur losses that would not have been incurred had the risk been hedged.

Derivatives Risk: Derivative instruments (such as those in which the Fund may invest, including futures, forwards and foreign currency transactions) are subject to changes in the value of the underlying assets or indices on which such instruments are based. There is no guarantee that the use of derivatives will be effective or that suitable transactions will be available. Even a small investment in derivatives may give rise to leverage risk and can have a significant impact on the Fund’s exposure to securities market values, interest rates or currency exchange rates. It is possible that the Fund’s liquid assets may be insufficient to support its obligations under its derivatives positions. The use of derivatives for other than hedging purposes may be considered a speculative activity, and involves greater risks than are involved in hedging. The use of derivatives may cause the Fund to incur losses greater than those that would have occurred had derivatives not been used. The Fund’s use of derivatives involves other risks, such as credit/counterparty risk relating to the other party to a

derivative contract (which is greater for forward currency contracts, uncleared swaps and other OTC derivatives), the risk of difficulties in pricing and valuation, the risk that changes in the value of a derivative may not correlate as expected with changes in the value of relevant assets, rates or indices, liquidity risk, allocation risk and the risk of losing more than any amounts paid or margin transferred to initiate derivatives positions. There is also the risk that the Fund may be unable to terminate or sell a derivative position at an advantageous time or price. The Fund’s derivative counterparties may experience financial difficulties or otherwise be unwilling or unable to honor their obligations, possibly resulting in losses to the Fund.

Interest Rate Risk: Interest rate risk is the risk that the value of the Fund’s investments will fall if interest rates rise. Generally, the value of fixed-income securities rises when prevailing interest rates fall and falls when interest rates rise. Interest rate risk generally is greater for funds that invest in fixed-income securities with relatively longer durations than for funds that invest in fixed-income securities with shorter durations. In addition, an economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Fund’s ability to sell them, negatively impacting the performance of the Fund. Potential future changes in government and/or central bank monetary policy and action may also affect the level of interest rates. Recently, there have been inflationary price movements, which have caused the fixed income securities markets to experience heightened levels of interest volatility and liquidity risk. Monetary policy measures have in the past, and may in the future, exacerbate risks associated with rising interest rates.

Leverage Risk: Leverage is the risk associated with securities or investment practices (e.g., borrowing and the use of certain derivatives) that multiply small index, market or asset-price movements into larger changes in value. The use of leverage increases the impact of gains and losses on the Fund’s returns, and may lead to significant losses if investments are not successful.

Liquidity Risk: Liquidity risk is the risk that the Fund may be unable to find a buyer for its investments when it seeks to sell them or to receive the price it expects. Decreases in the number of financial institutions willing to make markets in the Fund’s investments or in their capacity or willingness to transact may increase the Fund’s exposure to this risk. Events that may lead to increased redemptions, such as market disruptions or increases in interest rates, may also negatively impact the liquidity of the Fund’s investments when it needs to dispose of them. Markets may become illiquid quickly. If the Fund is forced to sell its investments at an unfavorable time and/or under adverse conditions in order to meet redemption requests, such sales could negatively affect the Fund. During times of market turmoil, there may be no buyers or sellers for securities in certain asset classes. Securities acquired in a private placement, such as Rule 144A securities, are generally subject to significant liquidity risk because they are subject to strict restrictions on resale and there may be no liquid secondary market or ready purchaser for such securities. In other circumstances, liquid investments may become illiquid. Derivatives, and particularly OTC derivatives, are generally subject to liquidity risk as well. Liquidity issues may also make it difficult to value the Fund’s investments. The Fund may invest in liquid investments that become illiquid due to financial distress, or geopolitical events such as sanctions, trading halts or wars.

Management Risk: A strategy used by the Fund’s portfolio managers may fail to produce the intended result.

Mortgage-Related and Asset-Backed Securities Risk: In addition to the risks associated with investments in fixed-income securities generally (for example, credit, liquidity, inflation and valuation risk), mortgage-related and asset-backed securities are subject to the risks of the mortgages and assets underlying the securities as well as prepayment risk, the risk that the securities may be prepaid and result in the reinvestment of the prepaid amounts in securities with lower yields than the prepaid obligations. Conversely, there is a risk that a rise in interest rates will extend the life of a mortgage-related or asset-backed security beyond the expected prepayment time, typically reducing the security’s value, which is called extension risk. The Fund also may incur a loss when there is a prepayment of securities that were purchased at a premium. The Fund’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.

Risk/Return Bar Chart and Table

The bar chart and table shown below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year-to-year and by showing how the Fund’s average annual returns for the one-year, five-year and life-of-fund periods compare to those of a broad-based securities market index that reflects the performance of the overall market applicable to the Fund and an additional index that represents the market sectors in which the Fund primarily invests. The Fund’s past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information is available online at im.natixis.com and/or by calling the Fund toll-free at 800-225-5478.

Total Returns for Class Y Shares


	Highest Quarterly Return: Fourth Quarter 2023, 7.62% Lowest Quarterly Return: Second Quarter 2022, -8.82%


Average Annual Total Returns
(for the periods ended December 31, 2023)	Past 1 Year	Past 5 Years	Life of Fund (2/28/17)
Class Y - Return Before Taxes	8.69%	0.84%	0.98%
Return After Taxes on Distributions	7.74%	-0.26%	-0.15%
Return After Taxes on Distributions and Sale of Fund Shares	5.15%	0.38%	0.42%
Class A - Return Before Taxes	3.92%	-0.30%	0.09%
Class N - Return Before Taxes	8.73%	0.87%	1.03%
Bloomberg Global Aggregate Bond Index - USD Hedged¹	7.15%	1.40%	1.65%
Bloomberg MSCI Global Green Bond Index - USD Hedged	9.55%	0.77%	1.30%

Effective May 1, 2024, the Fund’s primary broad-based performance index changed to the Bloomberg Global Aggregate Bond Index - USD Hedged. The Bloomberg Global Aggregate Bond Index - USD Hedged is a broad-based securities market index that represents the overall market applicable to the Fund. The Fund will retain the Bloomberg MSCI Global Green Bond Index - USD Hedged as its additional benchmark for performance comparison.

Management

Investment Adviser

Mirova US LLC (“Mirova US”)

Portfolio Managers

Marc Briand, has served as portfolio manager of the Fund since 2017.

Charles Portier, has served as portfolio manager of the Fund since 2018.

Bertrand Rocher, has served as portfolio manager of the Fund since 2020.

Each portfolio manager is an employee of Mirova, the parent company of Mirova US, and provides portfolio management through a personnel-sharing arrangement between Mirova and Mirova US.

Purchase and Sale of Fund Shares

Class A Shares

The following chart shows the investment minimums for various types of accounts:


Type of Account	Minimum Initial Purchase
Any account other than those listed below	$2,500
For shareholders participating in Natixis Funds’ Automatic Investment Plan	$1,000


Type of Account	Minimum Initial Purchase
For Traditional IRA, Roth IRA, Rollover IRA, SEP-IRA and Keogh plans	$1,000

There is no subsequent investment minimum for these shares. There is no initial investment minimum for:

•	Fee Based Programs (such as wrap accounts) where an advisory fee is paid to the broker-dealer or other financial intermediary. Please consult your financial representative to determine if your fee based program is subject to additional or different conditions or fees.

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Clients of a Registered Investment Adviser where the Registered Investment Adviser receives an advisory, management or consulting fee.

Class N Shares

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Sub-accounts held within an omnibus account, where the omnibus account has at least $1,000,000.

•	Funds of funds that are distributed by the Distributor.

Class Y Shares

Class Y shares of the Fund are generally subject to a minimum initial investment of $100,000. There is no subsequent investment minimum for these shares. There is no minimum initial investment for:

•	Fee Based Programs (such as wrap accounts) where an advisory fee is paid to the broker-dealer or other financial intermediary. Please consult your financial representative to determine if your fee based program is subject to additional or different conditions or fees.

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Certain Individual Retirement Accounts if the amounts invested represent rollover distributions from investments by any of the retirement plans invested in the Fund.

•	Clients of a Registered Investment Adviser where the Registered Investment Adviser receives an advisory, management or consulting fee.

•

At the discretion of Natixis Advisors, clients of Natixis Advisors and its affiliates may purchase Class Y shares of the Fund below the stated minimums.

Tax Information

Mirova Global Sustainable Equity Fund

Investment Goal

The Fund seeks long-term capital appreciation.

Fund Fees & Expenses

Shareholder Fees


(fees paid directly from your investment)	Class A	Class C	Class N	Class T	Class Y
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	5.75%	None	None	2.50%	None
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)	None*	1.00%	None	None	None
Redemption fees	None	None	None	None	None

*	A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.

Annual Fund Operating Expenses


(expenses that you pay each year as a percentage of the value of your investment)	Class A	Class C	Class N	Class T	Class Y
Management fees	0.80%	0.80%	0.80%	0.80%	0.80%
Distribution and/or service (12b-1) fees	0.25%	1.00%	0.00%	0.25%	0.00%
Other expenses	0.19%	0.19%	0.09%	0.19%¹	0.19%
Total annual fund operating expenses	1.24%	1.99%	0.89%	1.24%	0.99%
Fee waiver and/or expense reimbursement²^,³	0.04%	0.04%	0.00%	0.04%	0.04%
Total annual fund operating expenses after fee waiver and/or expense reimbursement	1.20%	1.95%	0.89%	1.20%	0.95%

1	Other expenses for Class T shares are estimated for the current fiscal year.

Mirova US LLC (“Mirova US” or the “Adviser”) has given a binding contractual undertaking to the Fund to limit the amount of the Fund’s total annual fund operating expenses to 1.20%, 1.95%, 0.90%, 1.20% and 0.95% of the Fund’s average daily net assets for Class A, C, N, T and Y shares, respectively, exclusive of brokerage expenses, interest expense, taxes, acquired fund fees and expenses, organizational and extraordinary expenses, such as litigation and indemnification expenses. This undertaking is in effect through April 30, 2025 and may be terminated before then only with the consent of the Fund’s Board of Trustees. The Adviser will be permitted to recover, on a class-by-class basis, management fees waived and/or expenses reimbursed to the extent that expenses in later periods fall below both (1) the class’ applicable expense limitation at the time such amounts were waived/reimbursed and (2) the class’ current applicable expense limitation. The Fund will not be obligated to repay any such waived/reimbursed fees and expenses more than one year after the end of the fiscal year in which the fees or expenses were waived/reimbursed.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods (except where indicated). The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same except that the example is based on the Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement assuming that such waiver and/or reimbursement for classes A, C, T and Y will only be in place through the date noted above and on the Total Annual Fund Operating Expenses for the remaining periods. The example for Class C shares for the ten-year period reflects the conversion to Class A shares after eight years. The example does not take into account brokerage commissions and other fees to financial intermediaries that you may pay on your purchases and sales of shares of the Fund. Although your actual costs may be higher or lower, based on these assumptions your costs would be:


If shares are redeemed:	1 year		3 years		5 years		10 years
Class A	$	690	$	942	$	1,213	$	1,985
Class C	$	298	$	621	$	1,069	$	2,120


If shares are redeemed:	1 year		3 years		5 years		10 years
Class N	$	91	$	284	$	493	$	1,096
Class T	$	369	$	630	$	910	$	1,709
Class Y	$	97	$	311	$	543	$	1,209


If shares are not redeemed:	1 year		3 years		5 years		10 years
Class C	$	198	$	621	$	1,069	$	2,120

Portfolio Turnover

Investments, Risks and Performance

Principal Investment Strategies

Under normal circumstances, the Fund will invest at least 80% of its net assets (plus any borrowings made for investment purposes) in equity securities. Equity securities may include common stocks, preferred stocks, depositary receipts and real estate investment trusts (“REITs”). The Fund invests in securities of companies located in no fewer than three countries, which may include the U.S. Under normal circumstances, the Fund will invest a percentage of its assets in securities of companies located outside the U.S. equal to at least the lesser of 40% or the percentage of foreign issuers in the Fund’s benchmark, the MSCI World Index, less 5%. The percentage of the Fund’s investments in foreign securities is at least partially based on the composition of the Fund’s benchmark. As a result, the Fund’s exposure to securities of companies located outside the U.S. may fluctuate in connection with variations in the foreign exposure of the Fund’s benchmark. The Fund may invest up to 25% of its assets in securities of companies located in emerging markets. Emerging markets are economies that the Adviser believes are not generally recognized to be fully developed markets, as measured by gross national income, financial market infrastructure, market capitalization and/or other factors. The Fund may invest in growth and value companies of any size and may also invest in initial public offerings.

In making its investment decisions, the Adviser uses a bottom-up approach focused on individual companies, rather than focusing on specific themes, specific industries or economic factors. The Adviser applies a thematic approach to investment idea generation, identifying securities of companies that it believes offer solutions to the major transitions that our world is going through. These transitions include (i) demographics, such as an aging population, (ii) environmental issues, such as water scarcity, (iii) technological advances, such as cloud computing, and (iv) governance changes, such as the growing importance of corporate responsibility. The Adviser applies a Minimum Standards Policy, as described further in the “More About Goals and Strategies” section below, which sets forth criteria for specific exclusions that the Adviser will consider as part of its ESG analysis.

The Adviser may sell a security due to a deterioration in the company’s fundamental quality, a change in thematic exposure or impact relative to the United Nations’ Sustainable Development Goals, a controversy alert such as one relating to human rights, or if the Adviser believes the security has little potential for price appreciation or there is greater relative value in other securities in the Fund’s investment universe.

Principal Investment Risks

The principal risks of investing in the Fund are summarized below. The Fund does not represent a complete investment program. You may lose money by investing in the Fund.

Equity Securities Risk: The value of the Fund’s investments in equity securities could be subject to unpredictable declines in the value of individual securities and periods of below-average performance in individual securities or in the equity market as a whole. Growth stocks are generally more sensitive to market movements than other types of stocks primarily because their stock prices are based heavily on future expectations. If the Adviser’s assessment of the prospects for a company’s growth is wrong, or if the Adviser’s judgment of how other investors will value the company’s growth is wrong, then the price of the company’s stock may fall or not approach the value that the Adviser has placed on it. Value stocks can perform differently from the market as a whole and from other types of stocks. Value stocks also present the risk that their lower valuations fairly reflect their business prospects and that investors will not agree that the stocks represent favorable investment opportunities, and they may fall out of favor with investors and underperform growth stocks during any given period. Securities issued in IPOs tend to involve greater market risk than other equity securities due, in part, to public perception and the lack of publicly

available information and trading history. In the event an issuer is liquidated or declares bankruptcy, the claims of owners of the issuer’s bonds generally take precedence over the claims of those who own preferred stock or common stock. Securities of real estate-related companies and REITs in which the Fund may invest may be considered equity securities, thus subjecting the Fund to the risks of investing in equity securities generally.

Small- and Mid-Capitalization Companies Risk: Compared to large-capitalization companies, small- and mid-capitalization companies are more likely to have limited product lines, markets or financial resources. Stocks of these companies often trade less frequently and in limited volume and their prices may fluctuate more than stocks of large-capitalization companies. As a result, it may be relatively more difficult for the Fund to buy and sell securities of small- and mid-capitalization companies.

ESG Investing Risk: The Fund’s ESG investment approach could cause the Fund to perform differently compared to funds that do not have such an approach or compared to the market as a whole. The Fund’s application of ESG-related considerations may affect the Fund’s exposure to certain issuers, industries, sectors, style factors or other characteristics and may impact the relative performance of the Fund—positively or negatively—depending on the relative performance of such investments. Excluding stocks that do not meet the ESG standards (as determined by the Adviser) results in a smaller universe of investments in which the Fund may invest, which may exacerbate this risk. Views on what constitutes “ESG investing,” and therefore what investments are appropriate for a fund that has an ESG investment approach, may differ by fund, adviser and investor. In evaluating an investment, a portfolio manager may be reliant upon information and data that may turn out to be incomplete, inaccurate or unavailable, which may negatively impact the portfolio manager’s assessment of an issuer’s ESG performance or the Fund’s performance generally. There is no guarantee that the Adviser’s efforts to select investments based on ESG practices will be successful.

Management Risk: A strategy used by the Fund’s portfolio managers may fail to produce the intended result.

Risk/Return Bar Chart and Table

necessarily indicate how the Fund will perform in the future. Updated performance information is available online at im.natixis.com and/or by calling the Fund toll-free at 800-225-5478.

Total Returns for Class Y Shares


	Highest Quarterly Return: Second Quarter 2020, 22.67% Lowest Quarterly Return: Second Quarter 2022, -15.11%


Average Annual Total Returns
(for the periods ended December 31, 2023)	Past 1 Year	Past 5 Years	Life of Fund (3/31/16)	Life of Class N (5/1/17)
Class Y - Return Before Taxes	18.63%	13.88%	11.53%	-
Return After Taxes on Distributions	18.46%	12.82%	10.66%	-
Return After Taxes on Distributions and Sale of Fund Shares	11.15%	11.11%	9.33%	-
Class A - Return Before Taxes	11.51%	12.25%	10.40%	-
Class C - Return Before Taxes	16.41%	12.73%	10.41%	-
Class N - Return Before Taxes	18.70%	13.94%	-	11.50%
Class T - Return Before Taxes	15.36%	13.02%	10.88%	-
MSCI World Index (Net)	23.79%	12.80%	10.69%	9.95%

Management

Investment Adviser

Mirova US LLC (“Mirova US”)

Portfolio Managers

Jens Peers, CFA^®, has served as co-portfolio manager of the Fund since 2016.

Hua Cheng, CFA^®, PhD, has served as co-portfolio manager of the Fund since 2016.

Soliane Varlet has served as co-portfolio manager of the Fund since 2022.

Ms. Varlet is an employee of Mirova, the parent company of Mirova US, and provides portfolio management through a personnel-sharing arrangement between Mirova and Mirova US.

Purchase and Sale of Fund Shares

Class A and C Shares

The following chart shows the investment minimums for various types of accounts:


Type of Account	Minimum Initial Purchase
Any account other than those listed below	$2,500
For shareholders participating in Natixis Funds’ Automatic Investment Plan	$1,000
For Traditional IRA, Roth IRA, Rollover IRA, SEP-IRA and Keogh plans	$1,000

There is no subsequent investment minimum for these shares. There is no initial investment minimum for:

•	Fee Based Programs (such as wrap accounts) where an advisory fee is paid to the broker-dealer or other financial intermediary. Please consult your financial representative to determine if your fee based program is subject to additional or different conditions or fees.

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Clients of a Registered Investment Adviser where the Registered Investment Adviser receives an advisory, management or consulting fee.

Class N Shares

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Sub-accounts held within an omnibus account, where the omnibus account has at least $1,000,000.

•	Funds of funds that are distributed by the Distributor.

Class T Shares

Class T shares of the Fund are not currently available for purchase.

Class Y Shares

Class Y shares of the Fund are generally subject to a minimum initial investment of $100,000. There is no subsequent investment minimum for these shares. There is no minimum initial investment for:

•	Fee Based Programs (such as wrap accounts) where an advisory fee is paid to the broker-dealer or other financial intermediary. Please consult your financial representative to determine if your fee based program is subject to additional or different conditions or fees.

•	Certain Retirement Plans. Please consult your retirement plan administrator to determine if your retirement plan is subject to additional or different conditions or fees imposed by the plan administrator.

•	Certain Individual Retirement Accounts if the amounts invested represent rollover distributions from investments by any of the retirement plans invested in the Fund.

•	Clients of a Registered Investment Adviser where the Registered Investment Adviser receives an advisory, management or consulting fee.

•

At the discretion of Natixis Advisors, clients of Natixis Advisors and its affiliates may purchase Class Y shares of the Fund below the stated minimums.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Mirova International Sustainable Equity Fund

Investment Goal

The Fund seeks long-term capital appreciation.

Fund Fees & Expenses

Shareholder Fees


(fees paid directly from your investment)	Class A	Class N	Class Y
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	5.75%	None	None
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)	None*	None	None
Redemption fees	None	None	None

*	A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.

Annual Fund Operating Expenses


(expenses that you pay each year as a percentage of the value of your investment)	Class A	Class N	Class Y
Management fees	0.80%	0.80%	0.80%
Distribution and/or service (12b-1) fees	0.25%	0.00%	0.00%
Other expenses	1.59%	1.48%	1.59%
Total annual fund operating expenses	2.64%	2.28%	2.39%
Fee waiver and/or expense reimbursement¹^,²	1.44%	1.38%	1.44%
Total annual fund operating expenses after fee waiver and/or expense reimbursement	1.20%	0.90%	0.95%

Mirova US LLC (“Mirova US” or the “Adviser”) has given a binding contractual undertaking to the Fund to limit the amount of the Fund’s total annual fund operating expenses to 1.20%, 0.90% and 0.95% of the Fund’s average daily net assets for Class A, N and Y shares, respectively, exclusive of brokerage expenses, interest expense, taxes, acquired fund fees and expenses, organizational and extraordinary expenses, such as litigation and indemnification expenses. This undertaking is in effect through April 30, 2025 and may be terminated before then only with the consent of the Fund’s Board of Trustees. The Adviser will be permitted to recover, on a class-by-class basis, management fees waived and/or expenses reimbursed to the extent that expenses in later periods fall below both (1) the class’ applicable expense limitation at the time such amounts were waived/reimbursed and (2) the class’ current applicable expense limitation. The Fund will not be obligated to repay any such waived/reimbursed fees and expenses more than one year after the end of the fiscal year in which the fees or expenses were waived/reimbursed.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods (except where indicated). The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same except that the example is based on the Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement assuming that such waiver and/or reimbursement will only be in place through the date noted above and on the Total Annual Fund Operating Expenses for the remaining periods. The example does not take into account brokerage commissions and other fees to financial intermediaries that you may pay on your purchases and sales of shares of the Fund. Although your actual costs may be higher or lower, based on these assumptions your costs would be:


If shares are redeemed:	1 year		3 years		5 years		10 years
Class A	$	690	$	1,219	$	1,773	$	3,277
Class N


	Class A	Class C	Class N	Class T*	Class Y
Gateway Equity Call Premium Fund	GCPAX	GCPCX	GCPNX	GCPTX	GCPYX
Gateway Fund	GATEX	GTECX	GTENX	GATTX	GTEYX
Mirova Global Green Bond Fund	MGGAX		MGGNX		MGGYX
Mirova Global Sustainable Equity Fund	ESGMX	ESGCX	ESGNX	ETSGX	ESGYX
Mirova International Sustainable Equity Fund	MRVAX		MRVNX		MRVYX
Vaughan Nelson Mid Cap Fund	VNVAX	VNVCX	VNVNX	VNVTX	VNVYX
Vaughan Nelson Small Cap Value Fund	NEFJX	NEJCX	VSCNX	NEJTX	NEJYX


Fund Summary	1
Gateway Equity Call Premium Fund	1
Gateway Fund	7
Mirova Global Green Bond Fund	13
Mirova Global Sustainable Equity Fund	20
Mirova International Sustainable Equity Fund	26
Vaughan Nelson Mid Cap Fund	31
Vaughan Nelson Small Cap Value Fund	37
Investment Goals, Strategies and Risks	43
More About Goals and Strategies	43
Gateway Equity Call Premium Fund	43
Gateway Fund	44
Mirova Global Green Bond Fund	45
Mirova Global Sustainable Equity Fund	46
Mirova International Sustainable Equity Fund	47
Vaughan Nelson Mid Cap Fund	48
Vaughan Nelson Small Cap Value Fund	49
All Funds	50
More About Risks	51
Management Team	57
Meet the Funds' Investment Advisers and Subadviser	57
Meet the Funds' Portfolio Managers	58
Additional Information	59
Fund Services	59
Investing in the Funds	59
How Sales Charges Are Calculated	61
Compensation to Securities Dealers	64
How to Purchase Shares	64
How to Redeem Shares	66
Exchanging or Converting Shares	68
Restrictions on Buying, Selling and Exchanging Shares	68
Self-Servicing Your Account	70
Restructuring and Liquidations	70
How Fund Shares are Priced	71
Dividends and Distributions	72
Tax Consequences	73
Additional Investor Services	74
Financial Performance	76
Appendix A - Intermediary Specific Information	A-1
Appendix B - Financial Intermediary Specific Commissions & Investment Minimum Waivers	B-1
Appendix C - Additional Index Information	C-1