485BPOS
Prospectus
March 1, 2023
Columbia Seligman Semiconductor and Technology ETF
An Actively Managed ETF
    
Ticker Symbol
SEMI
This prospectus provides important information about Columbia Seligman Semiconductor and Technology ETF (the Fund), an exchange-traded fund (ETF) that is a series of Columbia ETF Trust I (the Trust), that you should know before investing. Please read it carefully and keep it for future reference.
This ETF is different from traditional ETFs.
Traditional ETFs tell the public what assets they hold each day. This ETF will not. This may create additional risks for your investment. For example:
You may have to pay more money to trade this ETF’s shares. This ETF will provide less information to traders, who tend to charge more for trades when they have less information.
The price you pay to buy this ETF shares on an exchange may not match the value of the ETF’s portfolio. The same is true when you sell shares. These price differences may be greater for this ETF compared to other ETFs because it provides less information to traders.
These additional risks may be even greater in bad or uncertain market conditions.
This ETF will publish on its website each business day a “Tracking Basket” designed to help trading in shares of the ETF. While the Tracking Basket includes some of the ETF’s holdings, it is not the ETF’s actual portfolio.
The differences between this ETF and other ETFs may also have advantages. By keeping certain information about this ETF secret, this ETF may face less risk that other traders can predict or copy its investment strategy. This may improve the ETF’s performance. If other traders are able to copy or predict the ETF’s investment strategy, however, this may hurt the ETF’s performance.
For additional information regarding the unique attributes and risks of this ETF, see the section entitled “Principal Risks” in the Summary Prospectus and the Prospectus, and the sections “How the Fund Differs from Traditional Mutual Funds” and “How the Fund Differs from ETFs that Disclose their Portfolio Holdings Daily” in the Prospectus.
These securities have not been approved or disapproved by the Securities and Exchange Commission (SEC), nor has the SEC passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.
Shares of the Fund are listed and traded on NYSE Arca, Inc. (the Exchange).
No person has been authorized to give any information or to make any representations other than those contained in this prospectus and the Fund's Statement of Additional Information (SAI) dated March 1, 2023 (which is incorporated by reference into this prospectus and is legally a part of this prospectus) and, if given or made, such information or representations may not be relied upon as having been authorized by us.

Columbia Seligman Semiconductor and Technology ETF
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2 Prospectus 2023

Table of Contents
Columbia Seligman Semiconductor and Technology ETF
Summary of the Fund
Investment Objective
Columbia Seligman Semiconductor and Technology ETF (the Fund) seeks capital appreciation.
Fees and Expenses of the Fund
This 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, to financial intermediaries, which are not reflected in the table and example below. If such expenses were reflected, the expenses set forth below would be higher.
    
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management fees(a) 0.75%
Distribution and/or service (12b-1) fees 0.00%
Other expenses 0.00%
Total annual Fund operating expenses 0.75%
(a) Pursuant to the Investment Management Services Agreement with Columbia ETF Trust I on behalf of the Fund, Columbia Management Investment Advisers, LLC pays the operating costs and expenses of the Fund, but not taxes, interest, brokerage expenses, portfolio transaction expenses, and infrequent and/or unusual expenses.
 Example
The following example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example illustrates the hypothetical expenses that you would incur over the time periods indicated (whether or not shares are redeemed), and assumes that:
you invest $10,000 in the Fund for the periods indicated,
your investment has a 5% return each year, and
the Fund’s total annual operating expenses remain the same as shown in the Annual Fund Operating Expenses table above.
Although your actual costs may be higher or lower, based on the assumptions listed above, your costs would be:
    
  1 year 3 years 5 years 10 years
  $77 $240 $417 $930
Portfolio Turnover
The Fund may pay 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 when 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. For the fiscal period from March 29, 2022 (commencement of operations) to October 31, 2022, the Fund’s portfolio turnover rate was 19% of the average value of its portfolio.
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Table of Contents
Columbia Seligman Semiconductor and Technology ETF
Summary of the Fund (continued)
Principal Investment Strategies
The Fund is an actively managed exchange-traded fund (ETF) that operates pursuant to an exemptive order from the Securities and Exchange Commission (the Order) and is not required to publicly disclose its complete portfolio holdings each business day. Additional information about this appears below.
Under normal market conditions, the Fund invests at least 80% of its net assets in securities of semiconductor, semiconductor equipment and related technology companies (Semiconductor and Tech Companies). A company is considered a Semiconductor and Tech Company if, at the time of Fund investment, the company is categorized by the Global Industry Classification Standard (GICS®) as within the semiconductor and semiconductor equipment industry or at least 50% of the company’s revenues, sales, earnings or assets arises from or is dedicated to the design, development, manufacturing process, distribution or sale of semiconductors, other integrated circuits (ICs) or semiconductor equipment. A Semiconductor and Tech Company may also include a company that primarily internally sources/develops (versus purchasing from third parties) its own semiconductors, ICs or semiconductor equipment for its technology products. The companies that the Fund invests in generally operate in the following industries as categorized by GICS®: semiconductors and semiconductor equipment; communication equipment; electronic equipment, instruments and components; technology hardware, storage and peripherals; and software. The Fund has a policy of investing at least 25% of its assets in companies in the semiconductor and semiconductor equipment industry as categorized by GICS®.
The Fund may invest in securities of companies of any size, including small- and mid-capitalization companies. The Fund typically employs a focused portfolio investing style, generally holding between 30 and 50 securities. However, the Fund may at any time hold less or more securities than the range noted. The Fund is non-diversified, which means that it can invest a greater percentage of its assets in the securities of fewer issuers than can a diversified fund. The Fund will generally invest in common stocks. The Fund’s portfolio managers use extensive in-depth research into specific companies to find those companies that they believe offer significant prospects for future growth (i.e., growth stocks). The Fund may invest in or have investment exposure to foreign companies.
The Fund is an actively managed ETF that operates pursuant to the Order and is not required to publicly disclose its complete portfolio holdings each business day. Instead, the Fund publishes each business day on its website a “Tracking Basket,” which is designed to closely track the daily performance of the Fund but is not the Fund’s actual portfolio. The Tracking Basket is comprised of: select recently disclosed portfolio holdings and/or select securities from the universe from which the Fund’s investments are selected (Strategy Components); liquid ETFs that convey information about the types of instruments (that are not otherwise fully represented by the Strategy Components) in which the Fund invests (Representative ETFs); and cash and cash equivalents. The Tracking Basket often may include a significant percentage of the securities held in the Fund’s portfolio, but it will exclude (or modify the weightings of) certain securities held in the Fund’s portfolio, such as those securities that the Fund’s portfolio managers are actively looking to purchase or sell, or securities which, if disclosed, could increase the risk of front-running (trading ahead) or free-riding (mirroring) the Fund's investment strategy. For additional information regarding the Tracking Basket, see the section “How the Fund Differs from ETFs that Disclose their Portfolio Holdings Daily” in the Prospectus.
The Fund also publishes each business day on its website the “Tracking Basket Weight Overlap,” which is the percentage weight overlap between the holdings of the prior business day’s Tracking Basket compared to the holdings of the Fund that formed the basis for the Fund’s calculation of net asset value per share (NAV) at the end of the prior business day. The Tracking Basket Weight Overlap is designed to provide investors with an understanding of how similar the Tracking Basket is to the Fund’s actual portfolio in percentage terms.
The GICS® was developed by and/or is the exclusive property of MSCI, Inc. (MSCI®) and S&P Global Market Intelligence Inc. (S&P Global Market Intelligence). GICS® is a service mark of MSCI® and S&P Global Market Intelligence and has been licensed for use by Columbia Management Investment Advisers, LLC (the Fund's Investment Manager). Neither GICS®, MSCI®, nor S&P Global Market Intelligence are affiliated with the Fund, the Investment Manager or any Columbia entity.
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Table of Contents
Columbia Seligman Semiconductor and Technology ETF
Summary of the Fund (continued)
Principal Risks
An investment in the Fund involves risks, including Tracking Basket Structure Risk, Semiconductor and Semiconductor Equipment Industry Risk, Active Management Risk, Focused Portfolio Risk, and New Fund Risk, among others. Descriptions of these and other principal risks of investing in the Fund are provided below. There is no assurance that the Fund will achieve its investment objective and you may lose money. The value of the Fund’s holdings may decline, and the Fund’s net asset value (NAV) and share price may go down. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. 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 below carefully, because any one or more of these risks may result in losses to the Fund. 
Active Management Risk. The Fund is actively managed and its performance therefore will reflect, in part, the ability of the portfolio managers to make investment decisions that seek to achieve the Fund’s investment objective. The Fund is not an index fund (it does not seek to track the performance of an index), nor does it provide daily transparency into its portfolio holdings like most other ETFs. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives and/or strategies. Active trading of portfolio and Tracking Basket securities may result in added expenses, a lower return and increased tax liability, including relative to other ETFs.
 
Arbitrage Risk. Unlike ETFs that publicly disclose their complete portfolio holdings daily, the Fund discloses each business day the Tracking Basket and Tracking Basket Weight Overlap, which are intended to allow market participants to estimate the value of positions in the Fund’s shares. Although this information is designed to facilitate arbitrage opportunities in Fund shares to minimize bid/ask spreads and/or premiums or discounts between the market price and the NAV of the Fund’s shares, this structure is novel and there is no guarantee the Fund’s arbitrage mechanism will operate as intended or that the Fund will not experience greater premiums or discounts between the market price and NAV of the Fund’s shares and/or wider bid/ask spreads than those experienced by other ETFs. 
Authorized Participant Concentration Risk. Only an Authorized Participant (as defined below) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that may act as Authorized Participants, none of which are or will be obligated to engage in creation or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units, Fund shares may trade at a greater premium or discount between the market price and the NAV of the Fund’s shares and/or wider bid/ask spreads than those experienced by other ETFs. Additionally, the Fund could possibly face trading halts and/or delisting from the Exchange. This risk may be heightened due to the fact that the Fund does not disclose its complete portfolio holdings daily, unlike passive ETFs and certain other actively managed ETFs, and could be greater in times of market stress, including at both the Fund share level and at the Fund holdings level. 
Early/Late Close/Trading Halt Risk.  An exchange or market may close early, close late or issue trading halts on specific securities, or the ability to buy or sell certain securities may be restricted, which may result in the Fund being unable to buy or sell these securities. There may be circumstances where a security held in the Fund’s portfolio but not in the Tracking Basket does not have readily available market quotations. If the Investment Manager determines that such circumstance may affect the reliability of the Tracking Basket as an arbitrage vehicle, that information, along with the identity and weighting of that security in the Fund’s portfolio, will be publicly disclosed on the Fund’s website and the Investment Manager will assess appropriate remedial measures. In these circumstances, market participants may use this information to engage in certain predatory trading practices that may have the potential to harm the Fund and its shareholders. If securities representing 10% or more of the Fund’s portfolio do not have readily available market quotations, the Investment Manager will promptly request the Exchange to halt trading on the Fund, meaning that investors would not be able to trade Fund shares. 
Focused Portfolio Risk. Because the Fund may invest in a limited number of companies, the Fund as a whole is subject to greater risk of loss if any of those securities decline in price. 
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Table of Contents
Columbia Seligman Semiconductor and Technology ETF
Summary of the Fund (continued)
Foreign Securities Risk. Investments in or exposure to securities of foreign companies may involve heightened risks relative to investments in or exposure to securities of U.S. companies. Investing in securities of foreign companies subjects the Fund to the risks associated with an issuer’s (and any of its related companies’) country of organization and places of business operations, including risks related to political, regulatory, economic, social, diplomatic and other conditions or events (including, for example, military confrontations and actions, war, other conflicts, terrorism and disease/virus outbreaks and epidemics) occurring in the country or region, as well as risks associated with less developed custody and settlement practices. Foreign securities may be more volatile and less liquid than securities of U.S. companies, and are subject to the risks associated with potential imposition of economic and other sanctions against a particular foreign country, its nationals or industries or businesses within the country. In addition, foreign governments may impose withholding or other taxes on the Fund’s income, capital gains or proceeds from the disposition of foreign securities, which could reduce the Fund’s return on such securities. 
Fund Shares Liquidity Risk. Although the Fund’s shares are listed on the Exchange, there can be no assurance that an active, liquid or otherwise orderly trading market for shares will be established or maintained by market makers or Authorized Participants, particularly in times of stressed market conditions. There is no guarantee that the Fund will be able to attract market makers and Authorized Participants. There is no obligation for market makers to make a market in the Fund’s shares or for Authorized Participants to submit purchase or redemption orders for creation units. Accordingly, if such parties determine not to perform their respective functions, this could, such as during times of market stress, in turn, lead to variances between the market price of the Fund’s shares and the underlying value of those shares and bid/ask spreads could widen. Trading in Fund shares on the Exchange also may be disrupted or even halted due to market conditions or for reasons that, in the view of the Exchange, make trading in Fund shares inadvisable. In addition, trading in Fund shares on the Exchange may be subject to trading halts caused by extraordinary market volatility pursuant to the Exchange “circuit breaker” rules. There also can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund’s shares will continue to be met or will remain unchanged. 
Growth Securities Risk. Growth securities typically trade at a higher multiple of earnings than other types of equity securities. Accordingly, the market values of growth securities may never reach their expected market value and may decline in price. In addition, growth securities, at times, may not perform as well as value securities or the stock market in general, and may be out of favor with investors for varying periods of time. 
Issuer Risk. An issuer in which the Fund invests or to which it has exposure may perform poorly or below expectations, and the value of its securities may therefore decline, which may negatively affect the Fund’s performance. Underperformance of an issuer may be caused by poor management decisions, competitive pressures, breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters, military confrontations and actions, war, other conflicts, terrorism, disease/virus outbreaks, epidemics or other events, conditions and factors which may impair the value of an investment in the Fund and could result in a greater premium or discount between the market price and the NAV of the Fund's shares and wider bid/ask spreads than those experienced by other ETFs. 
Small- and Mid-Cap Stock Risk. Investments in small- and mid-capitalization companies (small- and mid-cap companies) often involve greater risks than investments in larger, more established companies (larger companies) because small- and mid-cap companies tend to have less predictable earnings and may lack the management experience, financial resources, product diversification and competitive strengths of larger companies. Securities of small- and mid-cap companies may be less liquid and more volatile than the securities of larger companies. 
Large-Cap Stock Risk. Investments in larger companies may involve certain risks associated with their larger size. For instance, larger companies may be less able to respond quickly to new competitive challenges, such as changes in consumer tastes or innovation from smaller competitors. Also, larger companies are sometimes less able to achieve as high growth rates as successful smaller companies, especially during extended periods of economic expansion. 
Market Price Relative to NAV Risk. Shares of the Fund may trade at prices that vary from Fund NAV. Shares of the Fund are listed for trading on the Exchange and are bought and sold in the secondary market at market prices that may differ, in some cases significantly, from their NAV. The NAV of the Fund will generally fluctuate with changes in 
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Table of Contents
Columbia Seligman Semiconductor and Technology ETF
Summary of the Fund (continued)
the market value of the Fund’s holdings. The market prices of shares, however, will generally fluctuate in response to changes in NAV, as well as the relative supply of, and demand for, Fund shares on the Exchange. Fund shares may trade at a greater premium or discount between the market price and the NAV of the Fund's shares and/or wider bid/ask spreads than those experienced by other ETFs, including ETFs that make their full portfolio holdings public on a daily or otherwise more frequent basis than the Fund. The Investment Manager cannot predict whether Fund shares will trade below, at or above their NAV. Price differences may result because of, among other factors, supply and demand forces in the secondary trading market for Fund shares. It is expected that these forces generally will be closely related to, but not identical to, the same forces influencing the prices of the Fund’s holdings. In this regard, if a shareholder purchases Fund shares at a time when the market price is at a premium to the NAV or sells shares at a time when the market price is at a discount to the NAV, the shareholder may sustain losses. Different investment strategies or techniques, including those intended to be defensive in nature, including, as examples, stop loss orders to sell an ETF’s shares in the secondary market during negative market events or conditions, such as a “flash crash” or other market disruptions, may not work as intended and may produce significant losses to investors. Investors should consult their financial intermediary prior to using any such investment strategies or techniques, or before investing in the Fund. 
Market Risk. The Fund may incur losses due to declines in the value of one or more securities in which it invests. These declines may be due to factors affecting a particular issuer, or the result of, among other things, political, regulatory, market, economic or social developments affecting the relevant market(s) more generally. In addition, turbulence in financial markets and reduced liquidity in equity, credit and/or fixed income markets may negatively affect many issuers, which could adversely affect the Fund’s ability to price or value hard-to-value assets in thinly traded and closed markets and could cause significant redemptions and operational challenges. Global economies and financial markets are 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. These risks may be magnified if certain events or developments adversely interrupt the global supply chain; in these and other circumstances, such risks might affect companies worldwide. As a result, local, regional or global events such as terrorism, war, other conflicts, natural disasters, disease/virus outbreaks and epidemics or other public health issues, recessions, depressions or other events – or the potential for such events – could have a significant negative impact on global economic and market conditions and could result in a greater premium or discount between the market price and the NAV of the Fund's shares and wider bid/ask spreads than those experienced by other ETFs. 
New Fund Risk. The Fund is a newly formed ETF that operates differently from ETFs that publish their full portfolio holdings daily. There can be no assurance that an active trading market will develop or be maintained or that the market for Fund shares will operate as intended, which could lead to the Fund’s shares trading at a greater premium or discount between the market price and the NAV of the Fund's shares and/or wider bid/ask spreads than other ETFs that publish their portfolio holdings on a daily basis, particularly during periods of market disruption or volatility. As a result, it may cost investors more to trade Fund shares than shares of other ETFs. There is no guarantee that the Fund will be able to attract market makers and Authorized Participants. Market makers and Authorized Participants are not obligated to make a market in the Fund’s shares or to submit purchase and redemption orders for creation units. Accordingly, investors in the Fund bear the risk that the Fund may not be successful, which could result in the Fund being liquidated at any time without shareholder approval and/or at a time that may not be favorable to shareholders. Such a liquidation could have negative tax consequences for shareholders. 
Non-Diversified Fund Risk. The Fund is non-diversified, which generally means that it may invest a greater percentage of its total assets in the securities of fewer issuers than a “diversified” fund. This increases the risk that a change in the value of any one investment held by the Fund could affect the overall value of the Fund more than it would affect that of a diversified fund holding a greater number of investments. Accordingly, the Fund's value will likely be more volatile than the value of a more diversified fund. 
Secondary Market Trading Risk. Investors buying or selling Fund shares will pay brokerage commissions or other charges imposed by brokers as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of Fund shares. The Fund has no public trading history and may operate differently from ETFs that publish their complete portfolio holdings on a daily basis, which could lead to the Fund shares trading at a greater premium or discount between the 
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Table of Contents
Columbia Seligman Semiconductor and Technology ETF
Summary of the Fund (continued)
market price and the NAV of the Fund's shares and/or wider bid/ask spreads (particularly during periods of market disruption or volatility) than those experienced by other ETFs. As a result, it may cost investors more to trade Fund shares than shares of other ETFs. 
Semiconductor and Semiconductor Equipment Industry Risk. The Fund will concentrate (have at least 25% of its assets) in companies in the semiconductor and semiconductor equipment industry as categorized by GICS®. Companies in the same or related industries may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund more vulnerable to unfavorable developments than funds that invest more broadly. Generally, the more broadly a fund invests, the more it spreads risk and potentially reduces the risks of loss and volatility. The Fund is sensitive to, and its performance may depend to a greater extent on, the overall condition of the semiconductor and semiconductor equipment industry. The risks of investments in the industry include: intense competition, both domestically and internationally, including competition from subsidized foreign competitors with lower production costs; wide fluctuations in securities prices due to risks of rapid obsolescence of products and related technology; economic performance of the customers of semiconductor and related companies; their research costs and the risks that their products may not prove commercially successful; and thin capitalization and limited product lines, markets, financial resources or quality management and personnel. These companies rely on a combination of patents, trade secret laws and contractual provisions to protect their technologies. The industry is characterized by frequent litigation regarding patent and other intellectual property rights, which may require such companies to defend against competitors’ assertions of intellectual property infringement or misappropriation. The international operations of many companies expose them to the risks associated with instability and changes in economic and political conditions, foreign currency fluctuations, changes in foreign regulations, tariffs, and trade disputes. Business conditions in this industry can change rapidly from periods of strong demand to periods of weak demand. Any future downturn in the industry could harm the business and operating results of these companies. The stock prices of companies in the industry have been and will likely continue to be volatile relative to the overall market. 
Tracking Basket Structure Risk. The Fund’s Tracking Basket structure may affect the price at which the Fund shares trade in the secondary market. Although the Tracking Basket is intended to provide investors with enough information to allow for an effective arbitrage mechanism that will keep the market price of the Fund at or close to the Fund’s NAV per share, there is a risk that market prices will vary significantly from NAV. ETFs trading on the basis of a published Tracking Basket may trade at a wider bid/ask spread than ETFs that publish their complete portfolio holdings on a daily basis and therefore, may cost investors more to trade. These risks may increase during periods of market disruption or volatility. In addition, although the Fund seeks to benefit from not disclosing portfolio holdings daily, market participants may attempt to use the Tracking Basket to identify the Fund’s trading strategy. If successful, this could result in such market participants engaging in certain predatory trading practices that may have the potential to harm the Fund and its shareholders, such as front-running (trading ahead) or free-riding (mirroring) the Fund’s strategy. 
Performance Information
The Fund has not had a full calendar year of operations as of the date of this prospectus and therefore performance information is not available. 
When available, the Fund intends to compare its performance to the performance of the PHLX Semiconductor Sector Index and the S&P 500 Index. 
When available, updated performance information can be obtained by calling toll-free 800.426.3750 or visiting columbiathreadneedleus.com/etfs
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Table of Contents
Columbia Seligman Semiconductor and Technology ETF
Summary of the Fund (continued)
Fund Management
Investment Manager: Columbia Management Investment Advisers, LLC
    
Portfolio Management   Role with Fund   Managed Fund Since
Paul Wick   Lead Portfolio Manager   2022
Shekhar Pramanick   Technology Team Member   2022
Sanjay Devgan   Technology Team Member   2022
    
Portfolio Implementation   Role with Fund   With the Fund Since
Christopher Lo, CFA   Implementation Portfolio Manager   2022
Purchase and Sale of Fund Shares
The Fund issues and redeems shares only through Authorized Participants (intermediaries, typically broker-dealers who have executed an agreement with the Fund's distributor that governs transactions in Fund creation units) in large blocks of shares, typically 25,000 shares, called Creation Units. Creation Units are issued and redeemed generally in-kind in exchange for the deposit or delivery of the securities and cash included, in the case of this Fund, in the Fund's Tracking Basket. However, the Fund also reserves the right to permit or require Creation Units to be issued in exchange entirely or in part for cash. As a general matter, the Fund expects to receive cash for (or, cash in lieu of) Representative ETFs held in the Tracking Basket. Except when aggregated in Creation Units, the Fund shares are not redeemable securities of the Fund.
Individual shares may only be purchased and sold on secondary markets through a financial intermediary, such as a broker-dealer or a bank. Because the Fund’s shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). You may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the ETF (bid) and the lowest price a seller is willing to accept for shares of the ETF (ask) when buying or selling shares in the secondary market (the bid/ask spread). Recent information, including information regarding the Fund’s NAV, market price, premiums and discounts, and bid/ask spread, is available at columbiathreadneedleus.com/etfs.
Tax Information
Distributions you receive from the Fund are taxed as ordinary income for federal income tax purposes, except to the extent designated as net capital gain, qualified dividend or return of capital and may also be subject to state or local taxes, unless you are investing through a tax-advantaged retirement plan account or are a tax-exempt investor.
Payments to Broker-Dealers and Other Financial Intermediaries
If you purchase shares 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 Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your financial advisor to recommend the Fund over another investment. Ask your financial advisor or visit your financial intermediary’s website for more information.
Prospectus 2023 9

Table of Contents
Columbia Seligman Semiconductor and Technology ETF
More Information About the Fund
Investment Objective
Columbia Seligman Semiconductor and Technology ETF (the Fund) seeks capital appreciation. The Fund’s investment objective is not a fundamental policy and may be changed by the Fund’s Board of Trustees without shareholder approval. Because any investment involves risk, there is no assurance the Fund’s investment objective will be achieved.
Principal Investment Strategies
The Fund is an actively managed exchange-traded fund (ETF) that operates pursuant to an exemptive order from the Securities and Exchange Commission (the Order) and is not required to publicly disclose its complete portfolio holdings each business day. Additional information about this appears below.
Under normal market conditions, the Fund invests at least 80% of its net assets in securities of semiconductor, semiconductor equipment and related technology companies (Semiconductor and Tech Companies). A company is considered a Semiconductor and Tech Company if, at the time of Fund investment, the company is categorized by the Global Industry Classification Standard (GICS®) as within the semiconductor and semiconductor equipment industry or at least 50% of the company’s revenues, sales, earnings or assets arises from or is dedicated to the design, development, manufacturing process, distribution or sale of semiconductors, other integrated circuits (ICs) or semiconductor equipment. A Semiconductor and Tech Company may also include a company that primarily internally sources/develops (versus purchasing from third parties) its own semiconductors, ICs or semiconductor equipment for its technology products. The companies that the Fund invests in generally operate in the following industries as categorized by GICS®: semiconductors and semiconductor equipment; communication equipment; electronic equipment, instruments and components; technology hardware, storage and peripherals; and software. The Fund has a policy of investing at least 25% of its assets in companies in the semiconductor and semiconductor equipment industry as categorized by GICS®.
The Fund may invest in securities of companies of any size, including small- and mid-capitalization companies. The Fund typically employs a focused portfolio investing style, generally holding between 30 and 50 securities. However, the Fund may at any time hold less or more securities than the range noted. The Fund is non-diversified, which means that it can invest a greater percentage of its assets in the securities of fewer issuers than can a diversified fund. The Fund will generally invest in common stocks. The Fund’s portfolio managers use extensive in-depth research into specific companies to find those companies that they believe offer significant prospects for future growth (i.e., growth stocks). The Fund may invest in or have investment exposure to foreign companies.
The Fund is an actively managed ETF that operates pursuant to the Order and is not required to publicly disclose its complete portfolio holdings each business day. Instead, the Fund publishes each business day on its website a “Tracking Basket,” which is designed to closely track the daily performance of the Fund but is not the Fund’s actual portfolio. The Tracking Basket is comprised of: select recently disclosed portfolio holdings and/or select securities from the universe from which the Fund’s investments are selected (Strategy Components); liquid ETFs that convey information about the types of instruments (that are not otherwise fully represented by the Strategy Components) in which the Fund invests (Representative ETFs); and cash and cash equivalents. The Tracking Basket often may include a significant percentage of the securities held in the Fund’s portfolio, but it will exclude (or modify the weightings of) certain securities held in the Fund’s portfolio, such as those securities that the Fund’s portfolio managers are actively looking to purchase or sell, or securities which, if disclosed, could increase the risk of front-running (trading ahead) or free-riding (mirroring) the Fund's investment strategy. The Tracking Basket is constructed utilizing a mathematical optimization process to minimize deviations in the daily returns of the Tracking Basket relative to the daily returns of the Fund. For additional information regarding the Tracking Basket, see the section “How the Fund Differs from ETFs that Disclose their Portfolio Holdings Daily” in the Prospectus.
The Fund also publishes each business day on its website the “Tracking Basket Weight Overlap,” which is the percentage weight overlap between the holdings of the prior business day’s Tracking Basket compared to the holdings of the Fund that formed the basis for the Fund’s calculation of net asset value per share (NAV) at the end of the prior business day. The Tracking Basket Weight Overlap is designed to provide investors with an understanding of how similar the Tracking Basket is to the Fund’s actual portfolio in percentage terms.
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Table of Contents
Columbia Seligman Semiconductor and Technology ETF
More Information About the Fund (continued)
The Fund uses a bottom-up stock selection approach. This means that Columbia Management Investment Advisers, LLC (the Investment Manager) uses extensive in-depth research into specific companies to find those companies that it believes offer significant prospects for future growth. In selecting individual securities, the Investment Manager generally looks for companies that it believes display or are expected to display:
High profit margins or return on capital;
Attractive valuation relative to expected earnings or cash flow;
Quality management; and/or
Unique competitive advantages.
The Fund generally sells a stock if the Investment Manager believes:
its target price is reached;
its valuation becomes excessive;
its earnings or revenue growth are disappointing;
its underlying fundamentals have deteriorated; and/or
more attractive investment opportunities are believed to be available.
The Fund’s investment policy with respect to 80% of its assets may be changed by the Fund’s Board of Trustees without shareholder approval as long as shareholders are given 60 days’ advance written notice of the change.
The GICS® was developed by and/or is the exclusive property of MSCI, Inc. (MSCI®) and S&P Global Market Intelligence Inc. (S&P Global Market Intelligence). GICS® is a service mark of MSCI® and S&P Global Market Intelligence and has been licensed for use by the Investment Manager. Neither GICS®, MSCI®, nor S&P Global Market Intelligence are affiliated with the Fund, the Investment Manager or any Columbia entity.
Principal Risks
An investment in the Fund involves risks, including Tracking Basket Structure Risk, Semiconductor and Semiconductor Equipment Industry Risk, Active Management Risk, Focused Portfolio Risk, and New Fund Risk, among others. Descriptions of these and other principal risks of investing in the Fund are provided below. There is no assurance that the Fund will achieve its investment objective and you may lose money. The value of the Fund’s holdings may decline, and the Fund’s net asset value (NAV) and share price may go down. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. 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 below carefully, because any one or more of these risks may result in losses to the Fund.
Active Management Risk. The Fund is actively managed and its performance therefore will reflect, in part, the ability of the portfolio managers to make investment decisions that seek to achieve the Fund’s investment objective. The Fund is not an index fund (it does not seek to track the performance of an index), nor does it provide daily transparency into its portfolio holdings like most other ETFs. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives and/or strategies. Active trading of portfolio and Tracking Basket securities may result in added expenses, a lower return and increased tax liability, including relative to other ETFs.
Arbitrage Risk. Unlike ETFs that publicly disclose their complete portfolio holdings daily, the Fund discloses each business day the Tracking Basket and Tracking Basket Weight Overlap, which are intended to allow market participants to estimate the value of positions in the Fund’s shares. Although this information is designed to facilitate arbitrage opportunities in Fund shares to minimize bid/ask spreads and/or premiums or discounts between the market price and the NAV of the Fund’s shares, this structure is novel and there is no guarantee the Fund’s arbitrage mechanism will operate as intended or that the Fund will not experience greater premiums or discounts between the market price and NAV of the Fund’s shares and/or wider bid/ask spreads than those experienced by other ETFs.
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Authorized Participant Concentration Risk. Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that may act as Authorized Participants, none of which are or will be obligated to engage in creation or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units, Fund shares may trade at a greater premium or discount between the market price and the NAV of the Fund’s shares and/or wider bid/ask spreads than those experienced by other ETFs. Additionally, the Fund could possibly face trading halts and/or delisting from the Exchange. This risk may be heightened due to the fact that the Fund does not disclose its complete portfolio holdings daily, unlike passive ETFs and certain other actively managed ETFs, and could be greater in times of market stress, including at both the Fund share level and at the Fund holdings level.
Early/Late Close/Trading Halt Risk.  An exchange or market may close early, close late or issue trading halts on specific securities, or the ability to buy or sell certain securities may be restricted, which may result in the Fund being unable to buy or sell these securities. There may be circumstances where a security held in the Fund’s portfolio but not in the Tracking Basket does not have readily available market quotations. If the Investment Manager determines that such circumstance may affect the reliability of the Tracking Basket as an arbitrage vehicle, that information, along with the identity and weighting of that security in the Fund’s portfolio, will be publicly disclosed on the Fund’s website and the Investment Manager will assess appropriate remedial measures. In these circumstances, market participants may use this information to engage in certain predatory trading practices that may have the potential to harm the Fund and its shareholders. If securities representing 10% or more of the Fund’s portfolio do not have readily available market quotations, the Investment Manager will promptly request the Exchange to halt trading on the Fund, meaning that investors would not be able to trade Fund shares.
Focused Portfolio Risk. The Fund, because it may invest in a limited number of companies, may have more volatility in its NAV and is considered to have more risk than a fund that invests in a greater number of companies because changes in the value of a single security may have a more significant effect, either negative or positive, on the Fund’s NAV. To the extent the Fund invests its assets in fewer securities, the Fund is subject to greater risk of loss if any of those securities decline in price.
Foreign Securities Risk. Investments in or exposure to securities of foreign companies may involve heightened risks relative to investments in or exposure to securities of U.S. companies. For example, foreign markets can be extremely volatile. Foreign securities may also be less liquid, making them more difficult to trade, than securities of U.S. companies so that the Fund may, at times, be unable to sell foreign securities at desirable times or prices. Brokerage commissions, custodial costs and other fees are also generally higher for foreign securities. The Fund may have limited or no legal recourse in the event of default with respect to certain foreign securities, including those issued by foreign governments. In addition, foreign governments may impose withholding or other taxes on the Fund’s income, capital gains or proceeds from the disposition of foreign securities, which could reduce the Fund’s return on such securities. In some cases, such withholding or other taxes could potentially be confiscatory. Other risks include: possible delays in the settlement of transactions or in the payment of income; generally less publicly available information about foreign companies; the impact of economic, political, social, diplomatic or other conditions or events (including, for example, military confrontations and actions, war, other conflicts, terrorism and disease/virus outbreaks and epidemics), possible seizure, expropriation or nationalization of a company or its assets or the assets of a particular investor or category of investors; accounting, auditing and financial reporting standards that may be less comprehensive and stringent than those applicable to domestic companies; the imposition of economic and other sanctions against a particular foreign country, its nationals or industries or businesses within the country; and the generally less stringent standard of care to which local agents may be held in the local markets. In addition, it may be difficult to obtain reliable information about the securities and business operations of certain foreign issuers. Governments or trade groups may compel local agents to hold securities in designated depositories that are not subject to independent evaluation. The less developed a country’s securities market is, the greater the level of risks. Economic sanctions may be, and have been, imposed against certain countries, organizations, companies, entities and/or individuals. Economic sanctions and other similar governmental actions could, among other things, effectively restrict or eliminate the Fund’s ability to purchase or sell securities, and thus may make the Fund’s investments in
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such securities less liquid or more difficult to value. In addition, as a result of economic sanctions, the Fund may be forced to sell or otherwise dispose of investments at inopportune times or prices, which could result in losses to the Fund and increased transaction costs. These conditions may be in place for a substantial period of time and enacted with limited advance notice to the Fund. The risks posed by sanctions against a particular foreign country, its nationals or industries or businesses within the country may be heightened to the extent the Fund invests significantly in the affected country or region or in issuers from the affected country that depend on global markets. Additionally, investments in certain countries may subject the Fund to a number of tax rules, the application of which may be uncertain. Countries may amend or revise their existing tax laws, regulations and/or procedures in the future, possibly with retroactive effect. Changes in or uncertainties regarding the laws, regulations or procedures of a country could reduce the after-tax profits of the Fund, directly or indirectly, including by reducing the after-tax profits of companies located in such countries in which the Fund invests, or result in unexpected tax liabilities for the Fund. Currency rates in foreign countries may fluctuate significantly over short or long periods of time for a number of reasons, including changes in interest rates, imposition of currency exchange controls and economic or political developments in the U.S. or abroad. The Fund may also incur currency conversion costs when converting foreign currencies into U.S. dollars and vice versa.
Fund Shares Liquidity Risk. Although the Fund’s shares are listed on the Exchange, there can be no assurance that an active, liquid or otherwise orderly trading market for shares will be established or maintained by market makers or Authorized Participants, particularly in times of stressed market conditions. There is no guarantee that the Fund will be able to attract market makers and Authorized Participants. There is no obligation for market makers to make a market in the Fund’s shares or for Authorized Participants to submit purchase or redemption orders for creation units. Accordingly, if such parties determine not to perform their respective functions, this could, such as during times of market stress, in turn, lead to variances between the market price of the Fund’s shares and the underlying value of those shares and bid/ask spreads could widen. Trading in Fund shares on the Exchange also may be disrupted or even halted due to market conditions or for reasons that, in the view of the Exchange, make trading in Fund shares inadvisable. In addition, trading in Fund shares on the Exchange may be subject to trading halts caused by extraordinary market volatility pursuant to the Exchange “circuit breaker” rules. There also can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund’s shares will continue to be met or will remain unchanged.
Growth Securities Risk. Growth securities typically trade at a higher multiple of earnings than other types of equity securities. Accordingly, the market values of growth securities may never reach their expected market value and may decline in price. In addition, growth securities, at times, may not perform as well as value securities or the stock market in general, and may be out of favor with investors for varying periods of time.
Issuer Risk. An issuer in which the Fund invests or to which it has exposure may perform poorly or below expectations, and the value of its securities may therefore decline, which may negatively affect the Fund’s performance. Underperformance of an issuer may be caused by poor management decisions, competitive pressures, breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters, military confrontations and actions, war, other conflicts, terrorism, disease/virus outbreaks, epidemics or other events, conditions and factors which may impair the value of an investment in the Fund and could result in a greater premium or discount between the market price and the NAV of the Fund's shares and wider bid/ask spreads than those experienced by other ETFs.
Small- and Mid-Cap Stock Risk. Securities of small- and mid-cap companies can, in certain circumstances, have a higher potential for gains than securities of larger companies but are more likely to have more risk than larger companies. For example, small- and mid-cap companies may be more vulnerable to market downturns and adverse business or economic events than larger companies because they may have more limited financial resources and business operations. Small- and mid-cap companies are also more likely than larger companies to have more limited product lines and operating histories and to depend on smaller and generally less experienced management teams. Securities of small- and mid-cap companies may trade less frequently and in smaller volumes and may be less liquid and fluctuate more sharply in value than securities of larger companies. When the Fund takes significant positions in small- and mid-cap companies with limited trading volumes, the liquidation of those
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  positions, particularly in a distressed market, could be prolonged and result in Fund investment losses that would affect the value of your investment in the Fund. In addition, some small- and mid-cap companies may not be widely followed by the investment community, which can lower the demand for their stocks.
Large-Cap Stock Risk. Investments in larger companies may involve certain risks associated with their larger size. For instance, larger companies may be less able to respond quickly to new competitive challenges, such as changes in consumer tastes or innovation from smaller competitors. Also, larger companies are sometimes less able to achieve as high growth rates as successful smaller companies, especially during extended periods of economic expansion.
Market Price Relative to NAV Risk. Shares of the Fund may trade at prices that vary from Fund NAV. Shares of the Fund are listed for trading on the Exchange and are bought and sold in the secondary market at market prices that may differ, in some cases significantly, from their NAV. The NAV of the Fund will generally fluctuate with changes in the market value of the Fund’s holdings. The market prices of shares, however, will generally fluctuate in response to changes in NAV, as well as the relative supply of, and demand for, Fund shares on the Exchange. Fund shares may trade at a greater premium or discount between the market price and the NAV of the Fund's shares and/or wider bid/ask spreads than those experienced by other ETFs, including ETFs that make their full portfolio holdings public on a daily or otherwise more frequent basis than the Fund. The Investment Manager cannot predict whether Fund shares will trade below, at or above their NAV. Price differences may result because of, among other factors, supply and demand forces in the secondary trading market for Fund shares. It is expected that these forces generally will be closely related to, but not identical to, the same forces influencing the prices of the Fund’s holdings. In this regard, if a shareholder purchases Fund shares at a time when the market price is at a premium to the NAV or sells shares at a time when the market price is at a discount to the NAV, the shareholder may sustain losses. Different investment strategies or techniques, including those intended to be defensive in nature, including, as examples, stop loss orders to sell an ETF’s shares in the secondary market during negative market events or conditions, such as a “flash crash” or other market disruptions, may not work as intended and may produce significant losses to investors. Investors should consult their financial intermediary prior to using any such investment strategies or techniques, or before investing in the Fund.
Market Risk. The Fund may incur losses due to declines in the value of one or more securities in which it invests. These declines may be due to factors affecting a particular issuer, or the result of, among other things, political, regulatory, market, economic or social developments affecting the relevant market(s) more generally. In addition, turbulence in financial markets and reduced liquidity in equity, credit and/or fixed income markets may negatively affect many issuers, which could adversely affect the Fund’s ability to price or value hard-to-value assets in thinly traded and closed markets and could cause significant redemptions and operational challenges. Global economies and financial markets are 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. These risks may be magnified if certain events or developments adversely interrupt the global supply chain; in these and other circumstances, such risks might affect companies worldwide. As a result, local, regional or global events such as terrorism, war, other conflicts, natural disasters, disease/virus outbreaks and epidemics or other public health issues, recessions, depressions or other events – or the potential for such events – could have a significant negative impact on global economic and market conditions and could result in a greater premium or discount between the market price and the NAV of the Fund's shares and wider bid/ask spreads than those experienced by other ETFs.
The large-scale invasion of Ukraine by Russia in February 2022 has resulted in sanctions and market disruptions, including declines in regional and global stock markets, unusual volatility in global commodity markets and significant devaluations of Russian currency. The extent and duration of the military action are impossible to predict but could be significant. Market disruption caused by the Russian military action, and any counter measures or responses thereto (including international sanctions, a downgrade in a country’s credit rating, purchasing and financing restrictions, boycotts, tariffs, changes in consumer or purchaser preferences, cyberattacks and espionage) could have severe adverse impacts on regional and/or global securities and commodities markets, including markets for oil and natural gas. These impacts may include reduced market liquidity, distress in credit markets, further disruption of global supply chains, increased risk of inflation, and limited access to investments in certain international markets and/or issuers. These developments and other related events could negatively impact Fund performance.
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The pandemic caused by coronavirus disease 2019 and its variants (COVID-19) has resulted in, and may continue to result in, significant global economic and societal disruption and market volatility due to disruptions in market access, resource availability, facilities operations, imposition of tariffs, export controls and supply chain disruption, among others. Such disruptions may be caused, or exacerbated by, quarantines and travel restrictions, workforce displacement and loss in human and other resources. The uncertainty surrounding the magnitude, duration, reach, costs and effects of the global pandemic, as well as actions that have been or could be taken by governmental authorities or other third parties, present unknowns that are yet to unfold. The impacts, as well as the uncertainty over impacts to come, of COVID-19 – and any other infectious illness outbreaks, epidemics and pandemics that may arise in the future – could negatively affect global economies and markets in ways that cannot necessarily be foreseen. In addition, the impact of infectious illness outbreaks and epidemics in less developed countries may be greater due to generally less established healthcare systems, governments and financial markets. Public health crises caused by the COVID-19 outbreak may exacerbate other pre-existing political, social and economic risks in certain countries or globally. The disruptions caused by COVID-19 could prevent the Fund from executing advantageous investment decisions in a timely manner and negatively impact the Fund’s ability to achieve its investment objective. Any such events could have a significant adverse impact on the value and risk profile of the Fund.
New Fund Risk. The Fund is a newly formed ETF that operates differently from ETFs that publish their full portfolio holdings daily. There can be no assurance that an active trading market will develop or be maintained or that the market for Fund shares will operate as intended, which could lead to the Fund’s shares trading at a greater premium or discount between the market price and the NAV of the Fund's shares and/or wider bid/ask spreads than other ETFs that publish their portfolio holdings on a daily basis, particularly during periods of market disruption or volatility. As a result, it may cost investors more to trade Fund shares than shares of other ETFs. There is no guarantee that the Fund will be able to attract market makers and Authorized Participants. Market makers and Authorized Participants are not obligated to make a market in the Fund’s shares or to submit purchase and redemption orders for creation units. Accordingly, investors in the Fund bear the risk that the Fund may not be successful, which could result in the Fund being liquidated at any time without shareholder approval and/or at a time that may not be favorable to shareholders. Such a liquidation could have negative tax consequences for shareholders.
Non-Diversified Fund Risk. The Fund is non-diversified, which generally means that it may invest a greater percentage of its total assets in the securities of fewer issuers than a “diversified” fund. This increases the risk that a change in the value of any one investment held by the Fund could affect the overall value of the Fund more than it would affect that of a diversified fund holding a greater number of investments. Accordingly, the Fund's value will likely be more volatile than the value of a more diversified fund.
Secondary Market Trading Risk. Investors buying or selling Fund shares will pay brokerage commissions or other charges imposed by brokers as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of Fund shares. The Fund has no public trading history and may operate differently from ETFs that publish their complete portfolio holdings on a daily basis, which could lead to the Fund shares trading at a greater premium or discount between the market price and the NAV of the Fund's shares and/or wider bid/ask spreads (particularly during periods of market disruption or volatility) than those experienced by other ETFs. As a result, it may cost investors more to trade Fund shares than shares of other ETFs.
Semiconductor and Semiconductor Equipment Industry Risk. The Fund will concentrate (have at least 25% of its assets) in companies in the semiconductor and semiconductor equipment industry as categorized by GICS®. Companies in the same or related industries may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund more vulnerable to unfavorable developments than funds that invest more broadly. Generally, the more broadly a fund invests, the more it spreads risk and potentially reduces the risks of loss and volatility.
The Fund is sensitive to, and its performance may depend to a greater extent on, the overall condition of the semiconductor and semiconductor equipment industry. The risks of investments in the industry include: intense competition, both domestically and internationally, including competition from subsidized foreign competitors with lower production costs; wide fluctuations in securities prices due to risks of rapid obsolescence of products and
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related technology; economic performance of the customers of semiconductor and related companies; their research costs and the risks that their products may not prove commercially successful; and thin capitalization and limited product lines, markets, financial resources or quality management and personnel. Semiconductor design and process methodologies are subject to rapid technological change requiring large expenditures, potentially requiring financing that may be difficult or impossible to obtain, for research and development in order to improve product performance and increase manufacturing yields. These companies rely on a combination of patents, trade secret laws and contractual provisions to protect their technologies. The process of seeking patent protection can be long and expensive. The industry is characterized by frequent litigation regarding patent and other intellectual property rights, which may require such companies to defend against competitors’ assertions of intellectual property infringement or misappropriation. Some companies are also engaged in other lines of business unrelated to the semiconductor business, and these companies may experience problems with these lines of business that could adversely affect their operating results. The international operations of many companies expose them to the risks associated with instability and changes in economic and political conditions, foreign currency fluctuations, changes in foreign regulations, tariffs, and trade disputes. Business conditions in this industry can change rapidly from periods of strong demand to periods of weak demand. Any future downturn in the industry could harm the business and operating results of these companies. The stock prices of companies in the industry have been and will likely continue to be volatile relative to the overall market.
The industry may also be affected by risks that affect the broader technology sector, including: government regulation, dramatic and often unpredictable changes in growth rates and competition for qualified personnel, a small number of companies representing a large portion of the technology semiconductor industry as a whole, cyclical market patterns, significant product price erosion hampering company profits, periods of over-capacity and production shortages, changing demand, variations in manufacturing costs and yields and significant expenditures for capital equipment and product development.
Tracking Basket Structure Risk. The Fund’s Tracking Basket structure may affect the price at which the Fund shares trade in the secondary market. Although the Tracking Basket is intended to provide investors with enough information to allow for an effective arbitrage mechanism that will keep the market price of the Fund at or close to the Fund’s NAV per share, there is a risk that market prices will vary significantly from NAV. ETFs trading on the basis of a published Tracking Basket may trade at a wider bid/ask spread than ETFs that publish their complete portfolio holdings on a daily basis and therefore, may cost investors more to trade. These risks may increase during periods of market disruption or volatility. In addition, although the Fund seeks to benefit from not disclosing portfolio holdings daily, market participants may attempt to use the Tracking Basket to identify the Fund’s trading strategy. If successful, this could result in such market participants engaging in certain predatory trading practices that may have the potential to harm the Fund and its shareholders, such as front-running (trading ahead) or free-riding (mirroring) the Fund’s strategy.
How the Fund Differs from Traditional Mutual Funds
Redeemability. Traditional mutual fund shares may be bought from, and redeemed with, the issuing fund for cash at NAV typically calculated once at the end of each business day. Shares of an ETF, by contrast, cannot be purchased from or redeemed with the ETF except by or through Authorized Participants, and then generally in-kind in exchange for the deposit or delivery of the securities and cash included, in the case of this Fund, in the Fund's Tracking Basket. However, the Fund also reserves the right to permit or require Creation Units to be issued in exchange entirely or in part for cash. As a general matter, the Fund expects to receive cash for (or, cash in lieu of) Representative ETFs held in the Tracking Basket. Except when aggregated in Creation Units, the Fund shares are not redeemable securities of the Fund. In addition, ETFs issue and redeem shares on a continuous basis only in large blocks of shares, typically 25,000 shares (which is the case for the Fund), called Creation Units.
With respect to foreign securities, the Fund may pay redemption proceeds more than seven (but no more than fifteen) calendar days after the Fund's shares are tendered for redemption as a result of local market holidays. This risk applies to those who purchase and sell Creation Units directly from and to the Fund and does not apply to investors who will buy and sell shares of the Fund in secondary market transactions on the Exchange through a broker or other financial intermediary.
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Exchange Listing. Unlike traditional mutual fund shares, the Fund’s shares are listed for trading on the Exchange. Investors can purchase and sell shares on the secondary market through a broker or other financial intermediary (collectively, financial intermediary(ies)). There can be no assurance that the Fund's shares will continue to trade on the Exchange or that the Fund's shares will continue to meet the requirements for listing or trading on the Exchange. Investors purchasing shares in the secondary market through a brokerage account or with the assistance of a financial intermediary may be subject to brokerage commissions and charges. Secondary-market transactions do not occur at NAV, but at market prices that change throughout the day, based on the supply of, and demand for, shares and on changes in the prices of the Fund’s portfolio holdings. The market price of shares may differ from the NAV of the Fund. The difference between market price of shares and the NAV of the Fund is called a premium when the market price is above the reported NAV and called a discount when the market price is below the reported NAV. The market price of the Fund's shares may deviate significantly from the NAV of the shares, for example, in times of extreme market volatility or other conditions.
Tax Treatment. The Fund’s structure may provide for enhanced tax efficiency relative to a traditional mutual fund’s structure. Specifically, to the extent the Fund redeems its shares in kind, the distribution of portfolio securities to meet such redemption requests may mitigate certain adverse tax consequences associated with traditional mutual fund shares to continuing Fund shareholders. This is because traditional mutual funds typically sell portfolio securities to obtain cash to meet redemptions and, as necessary, may recognize taxable gains in connection with such sales. By contrast, to the extent the Fund redeems its shares in kind, as opposed to in cash, the Fund’s in-kind redemption mechanism will potentially reduce, relative to a traditional mutual fund, taxable gains resulting from redemptions. However, the Fund cannot predict to what extent, if any, it will redeem its shares in kind rather than in cash, particularly during the Fund’s growth stages when portfolio changes are more likely to be implemented within the Fund rather than through the in-kind redemption mechanism. Nor can the Fund predict the extent to which any such in-kind redemptions will reduce the taxable gain recognized in connection therewith.
ETFs generally are able to make in-kind redemptions and avoid being taxed on gain on the distributed portfolio securities at the Fund level. Because the Fund may effect redemptions partly or entirely in cash, rather than in-kind distributions, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. If the Fund recognizes gain on these sales, this generally will cause the Fund to recognize gain it might not otherwise have recognized, or to recognize such gain sooner than would otherwise be required if it were to distribute portfolio securities in-kind. The Fund generally intends to distribute these gains to shareholders to avoid being taxed on this gain at the Fund level and otherwise comply with the special tax rules that apply to it. This strategy may cause shareholders to be subject to tax on gains they would not otherwise be subject to, or at an earlier date than, if they had made an investment in a different ETF. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid and may involve considerable brokerage fees and taxes. These brokerage fees and taxes, which will be higher than if the Fund sold and redeemed its shares principally in-kind, will be passed on to purchasers and redeemers of Creation Units in the form of creation and redemption transaction fees.
How the Fund Differs from ETFs that Disclose their Portfolio Holdings Daily
The Fund is an actively managed ETF that operates pursuant to the Order. Like other ETFs, shares of the Fund are generally purchased and redeemed in creation unit aggregations through Authorized Participants, shares of the Fund are listed and traded on a stock exchange, and individual investors can purchase or sell shares in less than creation unit sizes and for cash in the secondary market through a financial intermediary, such as a broker. The Fund’s creation units generally can be purchased or redeemed in-kind in exchange for the Strategy Components included in the Fund’s Tracking Basket, together with an amount of cash corresponding to the value of the Representative ETFs and cash and cash equivalents that form the remainder of the Tracking Basket.
Tracking Basket Structure. However, the Fund has some unique features that differentiate it from other ETFs. As described above, the Fund does not disclose its complete portfolio holdings each business day. Instead, the Fund discloses other information to the market that is designed to facilitate arbitrage opportunities in Fund shares to maintain efficient secondary market trading of shares. Each business day before the commencement of trading in shares on the Exchange, the Fund publishes on its website a Tracking Basket that is designed to closely track the
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daily performance of the Fund. The Tracking Basket is comprised of Strategy Components (select recently disclosed portfolio holdings and/or select securities from the universe from which the Fund’s investments are selected), Representative ETFs (liquid ETFs that convey information about the types of instruments (that are not otherwise fully represented by the Strategy Components) in which the Fund invests), and cash and cash equivalents. Representative ETFs are selected for inclusion in the Tracking Basket such that, when aggregated with the other Tracking Basket components, the Tracking Basket corresponds to the Fund’s overall holdings exposure. Representative ETFs may constitute no more than 50% of the Tracking Basket’s assets on each business day at the time that the Tracking Basket is published. The Tracking Basket is constructed utilizing an optimization process to minimize daily deviations in return of the Tracking Basket relative to the Fund and is used to facilitate the creation/redemption process and arbitrage. The Tracking Basket is typically expected to be rebalanced on schedule with the public disclosure of the Fund’s holdings; however, a new Tracking Basket may be generated as frequently as daily. In determining whether to rebalance the Tracking Basket, the Investment Manager will consider various factors, including liquidity of the securities in the Tracking Basket, tracking error of the Tracking Basket relative to the Fund, and the cost to create and trade the Tracking Basket.
Tracking Basket Weight Overlap. In addition to the daily disclosure of the Tracking Basket, the Fund publishes the “Tracking Basket Weight Overlap” on its website on each business day before the commencement of trading in Fund shares on the Exchange. The Tracking Basket Weight Overlap is the percentage weight overlap between the holdings of the prior day’s Tracking Basket compared to the holdings of the Fund that formed the basis for the Fund’s calculation of NAV at the end of the prior business day. It is calculated by taking the lesser weight of each asset held in common between the Fund’s portfolio and the Tracking Basket, and adding the totals. The Tracking Basket Weight Overlap is intended to provide investors with an understanding of the degree to which the Tracking Basket and the Fund’s portfolio overlap and help investors evaluate the risk that the performance of the Tracking Basket may deviate from the performance of the portfolio holdings of the Fund.
The Fund is subject to ongoing monitoring of the level of market price premium or discount to NAV, bid/ask spreads on market transactions, and the tracking error of the Tracking Basket relative to the Fund, with reporting to the Fund’s Board of Trustees at certain thresholds in each case.
Information Available at Fund Website and Fund Portfolio Holdings Disclosure
Information about the Fund may be found at columbiathreadneedleus.com/etfs. Among other things, this website includes the Summary Prospectus, this prospectus, the SAI and, when available, the Fund’s annual and semiannual reports.
Information regarding how often the Fund shares traded on the Exchange at a price above (at a premium) or below (at a discount) the NAV of the Fund during the prior calendar year and subsequent quarters, when available, can also be found on the Fund’s website, columbiathreadneedleus.com/etfs. Additionally, each business day before the commencement of trading of Fund shares, the Fund will publish on the Fund’s website further information, including: the Tracking Basket, the Tracking Basket Weight Overlap, the prior business day’s NAV and the closing price or bid/ask price, a calculation of the premium or discount of the prior business day's closing price or bid/ask price against the prior business day's NAV. The Fund also discloses on its website its full portfolio holdings, including the name, identifier, market value and weight of each security and instrument in the portfolio, as of month-end approximately, but no earlier than, 15 calendar days after such month-end.
In addition, the Tracking Basket, which identifies the securities (cash in lieu of Representative ETFs, as described above) that may be delivered in exchange for purchases and redemptions of Creation Units, are publicly disseminated each business day prior to the opening of trading on the Exchange via the National Securities Clearing Corporation (NSCC).
Permissible Investments and Other Fund Policies
This section describes certain investment strategies and policies that the Fund may utilize in pursuit of its investment objective and some additional factors and risks involved with investing in the Fund.
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More Information About the Fund (continued)
Under the terms of the Order, the Fund’s investments are limited to the following: ETFs, notes, common stocks, preferred stocks, American Depositary Receipts (ADRs), real estate investment trusts (REITs), commodity pools, metals trusts, and currency trusts, in each case that are traded on a U.S. securities exchange; common stocks listed on a foreign exchange that trade on such exchange contemporaneously with the Fund’s shares; exchange-traded futures (where the future contract’s reference asset is an asset that the Fund could invest in directly, or in the case of an index future, is based on an index of a type of asset that the Fund could invest in directly) that are traded on a U.S. futures exchange contemporaneously with the Fund’s shares; and cash and cash equivalents, which are short-term U.S. Treasury securities, government money market funds, and repurchase agreements (collectively, Permissible Investments). The Fund may invest in any of the Permissible Investments. These investments and their risks are described in the SAI. The Fund may not borrow for investment purposes or hold short positions. The Fund may not purchase any securities that are illiquid investments at the time of purchase.
Investing Defensively
The Fund may from time to time take temporary defensive investment positions that may be inconsistent with the Fund’s principal investment strategies in attempting to respond to adverse market, economic, political, social or other conditions, including, without limitation, investing some or all of its assets in money market instruments or shares of affiliated or unaffiliated government money market funds or holding some or all of its assets in cash or cash equivalents. The Fund may take such defensive investment positions for as long a period as deemed necessary.
The Fund may not achieve its investment objective while it is investing defensively. Investing defensively may adversely affect Fund performance. During these times, the portfolio managers may make frequent portfolio holding changes, which could result in increased trading expenses and taxes, and decreased Fund performance.
Other Strategic and Investment Measures
The Fund may also from time to time take temporary portfolio positions that may or may not be consistent with the Fund’s principal investment strategies in attempting to respond to adverse market, economic, political, social or other conditions, including, without limitation, investing in exchange-traded futures contracts for various purposes, including among others, in seeking to reduce investment exposures, or in seeking to achieve indirect investment exposures, to a sector, country, region or currency where the Investment Manager believes such positioning is appropriate. The Fund may take such portfolio positions for as long a period as deemed necessary. While the Fund is so positioned, the Fund may not achieve its investment objective. Investing in this manner may adversely affect Fund performance. During these times, the portfolio managers may make frequent portfolio holding changes, which could result in increased trading expenses and taxes, and decreased Fund performance.
Understanding Annual Fund Operating Expenses
The Fund’s annual operating expenses, as presented in the Annual Fund Operating Expenses table in the Fees and Expenses of the Fund section of this prospectus, generally are based on expenses incurred during the Fund’s most recently completed fiscal year and are expressed as a percentage (expense ratio) of the Fund’s average net assets during that fiscal year. The expense ratio reflects the Fund’s fee arrangements as of the date of this prospectus and, unless indicated otherwise, is based on expenses incurred during the Fund’s most recent fiscal year. The Fund’s assets will fluctuate, but unless indicated otherwise in the Annual Fund Operating Expenses table, no adjustments have been or will be made to the expense ratio to reflect any differences in the Fund’s average net assets between the most recently completed fiscal year and the date of this prospectus or a later date. As applicable, any commitment by the Investment Manager and/or its affiliates to waive fees and/or cap (reimburse) expenses is expected, in part, to limit the impact of any increase in the Fund’s expense ratio that would otherwise result because of a decrease in the Fund’s assets in the current fiscal year. The Fund’s annual operating expenses are comprised of (i) investment management fees, (ii) distribution and/or service fees, and (iii) other expenses. No distribution or service fees are currently paid by the Fund, and there are no current plans to impose these fees.
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Columbia Seligman Semiconductor and Technology ETF
More Information About the Fund (continued)
Primary Service Provider Contracts
The Fund enters into contractual arrangements (Service Provider Contracts) with various service providers, including, among others, the Investment Manager, the administrator, the distributor, the transfer agent and the Fund’s custodian. The Fund’s Service Provider Contracts are solely among the parties thereto. Shareholders are not parties to, or intended to be third-party beneficiaries of, any Service Provider Contracts. Further, this prospectus, the SAI and any Service Provider Contracts are not intended to give rise to any agreement, duty, special relationship or other obligation between the Fund and any investor, or give rise to any contractual, tort or other rights in any individual shareholder, group of shareholders or other person, including any right to assert a fiduciary or other duty, enforce the Service Provider Contracts against the parties or to seek any remedy thereunder, either directly or on behalf of the Fund. Nothing in the previous sentence should be read to suggest any waiver of any rights under federal or state securities laws.
The Investment Manager
Columbia Management Investment Advisers, LLC is located at 290 Congress Street, Boston, MA 02210 and serves as investment adviser to the Columbia Funds, including the Fund. The Investment Manager is a registered investment adviser and a wholly-owned subsidiary of Ameriprise Financial, Inc. (Ameriprise Financial). The Investment Manager’s management experience covers all major asset classes, including equity securities, debt instruments and money market instruments. In addition to serving as an investment adviser to traditional mutual funds, exchange-traded funds and closed-end funds, the Investment Manager acts as an investment adviser for itself, its affiliates, individuals, corporations, retirement plans, private investment companies and financial intermediaries.
Subject to oversight by the Board, the Investment Manager manages the day-to-day operations of the Fund.
The SEC has issued an order that permits the Investment Manager, subject to the approval of the Board, to appoint affiliated and unaffiliated subadvisers by entering into subadvisory agreements with them, and to change in material respects the terms of those subadvisory agreements, including the fees paid thereunder, for the Fund without first obtaining shareholder approval, thereby avoiding the expense and delays typically associated with obtaining shareholder approval. The Fund furnishes shareholders with information about new subadvisers retained in reliance on the order within 90 days after hiring the subadviser. The Investment Manager and its affiliates may have other relationships, including significant financial relationships, with current or potential subadvisers or their affiliates, which may create certain conflicts of interest. When making recommendations to the Board to appoint or to change a subadviser, or to change the terms of a subadvisory agreement, the Investment Manager discloses to the Board the nature of any such material relationships. The SEC has issued a separate order that permits the Board to approve new subadvisory agreements or material changes to existing subadvisory agreements at a meeting that is not in person, provided that the Trustees are able to participate in the meeting using a means of communication that allows them to hear each other simultaneously during the meeting and other conditions of the order are satisfied. At present, the Investment Manager has not engaged any investment subadviser for the Fund.
The Fund pays the Investment Manager a fee for its investment advisory services. The fee is calculated as a percentage of the daily net assets of the Fund and is paid monthly. In return for this fee (which is sometimes referred to as a unitary or unified fee), the Investment Manager has agreed to pay the operating costs and expenses of the Fund other than the following expenses, which will be paid by the Fund: taxes, interest incurred on borrowing by the Fund, if any, brokerage fees and commissions, interest and fee expense related to the Fund’s participation in inverse floater structures and any other portfolio transaction expenses, infrequent and/or unusual expenses, including without limitation litigation expenses, distribution and/or service fees, expenses incurred in connection with lending securities, and any other expenses approved by the Board. For the Fund’s most recent fiscal year, investment advisory services fees paid to the Investment Manager by the Fund amounted to 0.75% of average daily net assets of the Fund, before any applicable reimbursements.
A discussion regarding the basis for the Board’s approval of the investment management services agreement with the Investment Manager is available in the Fund’s semiannual report to shareholders for the fiscal period ended April 30, 2022.
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More Information About the Fund (continued)
A discussion regarding the basis for the Board’s approval of the renewal of the investment management services agreement with the Investment Manager is available in the Fund’s annual report to shareholders for the fiscal year ended October 31, 2022.
Portfolio Managers
Information about the portfolio managers primarily responsible for overseeing the Fund’s investments is shown below. The SAI provides additional information about the portfolio managers, including information relating to compensation, other accounts managed by the portfolio managers, and ownership by the portfolio managers of Fund shares.
    
Portfolio Management   Role with Fund   Managed Fund Since
Paul Wick   Lead Portfolio Manager   2022
Shekhar Pramanick   Technology Team Member   2022
Sanjay Devgan   Technology Team Member   2022
Mr. Wick joined one of the Columbia Management legacy firms or acquired business lines in 1987. Mr. Wick is Team Leader and Portfolio Manager for the Columbia Seligman Technology strategies. Mr. Wick began his investment career in 1987 and earned a B.A. from Duke and an M.B.A. from Duke’s Fuqua School of Business.
Dr. Pramanick joined the Investment Manager in 2012. Dr. Pramanick began his investment career in 1993 and earned a B.S. from the National Institute of Technology, an M.S. from the University of Oregon and a Ph.D. from North Carolina State University.
Mr. Devgan joined the Investment Manager in 2012. Mr. Devgan began his investment career in 1995 and earned a B.S. from University of California and an M.B.A. from Santa Clara University.
    
Portfolio Implementation   Role with Fund   With the Fund Since
Christopher Lo, CFA   Implementation Portfolio Manager   2022
Dr. Lo joined one of the Columbia Management legacy firms or acquired business lines in 1998. Dr. Lo began his investment career in 1998 and earned a B.S. and M.E. from Rensselaer Polytechnic Institute, an M.B.A. from the Stern School of Business at New York University and a doctoral degree in professional studies (DPS) from Pace University, with a concentration in finance and international economics.
Other Service Providers
ALPS Distributors, Inc. (the Distributor), 1290 Broadway, Suite 1100, Denver, CO 80203, serves as the distributor of Creation Units for the Fund on an agency basis. The Distributor does not maintain a secondary market in shares.
BNY Mellon Corporation (BNY Mellon), 240 Greenwich Street, New York, NY 10286, is the administrator, fund accountant, transfer agent and custodian for the Fund.
PricewaterhouseCoopers LLP, 45 South Seventh Street, Suite 3400, Minneapolis, MN 55402, serves as the Fund’s independent registered public accounting firm. The independent registered public accounting firm is responsible for auditing the annual financial statements of the Fund.
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More Information About the Fund (continued)
Other Roles and Relationships of Ameriprise Financial and its Affiliates — Certain Conflicts of Interest
The Investment Manager provides various services to the Fund and other Columbia Funds for which it is compensated. Ameriprise Financial and its affiliates may also provide other services to these funds and be compensated for them.
The Investment Manager and its affiliates may provide investment advisory and other services to other clients and customers substantially similar to those provided to the Columbia Funds. These activities, and other financial services activities of Ameriprise Financial and its affiliates, may present actual and potential conflicts of interest and introduce certain investment constraints.
Ameriprise Financial is a major financial services company, engaged in a broad range of financial activities beyond the fund-related activities of the Investment Manager, including, among others, insurance, broker-dealer (sales and trading), asset management, banking and other financial activities. These additional activities may involve multiple advisory, financial, insurance and other interests in securities and other instruments, and in companies that issue securities and other instruments, that may be bought, sold or held by the Columbia Funds.
Conflicts of interest and limitations that could affect a Columbia Fund may arise from, for example, the following:
compensation and other benefits received by the Investment Manager and other Ameriprise Financial affiliates related to the management/administration of a Columbia Fund and the sale of its shares;
the allocation of, and competition for, investment opportunities among the Fund, other funds and accounts advised/managed by the Investment Manager and other Ameriprise Financial affiliates, or Ameriprise Financial itself and its affiliates;
separate and potentially divergent management of a Columbia Fund and other funds and accounts advised/managed by the Investment Manager and other Ameriprise Financial affiliates;
regulatory and other investment restrictions on investment activities of the Investment Manager and other Ameriprise Financial affiliates and accounts advised/managed by them;
insurance and other relationships of Ameriprise Financial affiliates with companies and other entities in which a Columbia Fund invests; and
regulatory and other restrictions relating to the sharing of information between Ameriprise Financial and its affiliates, including the Investment Manager, and a Columbia Fund.
The Investment Manager and Ameriprise Financial have adopted various policies and procedures that are intended to identify, monitor and address conflicts of interest. However, there is no assurance that these policies, procedures and disclosures will be effective.
Additional information about Ameriprise Financial and the types of conflicts of interest and other matters referenced above is set forth in the Investment Management and Other Services — Other Roles and Relationships of Ameriprise Financial and its Affiliates — Certain Conflicts of Interest section of the SAI. Investors in the Columbia Funds should carefully review these disclosures and consult with their financial advisor if they have any questions.
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More Information About the Fund (continued)
Certain Legal Matters
Ameriprise Financial and certain of its affiliates are involved in the normal course of business in legal proceedings which include regulatory inquiries, arbitration and litigation, including class actions concerning matters arising in connection with the conduct of its activities as a diversified financial services firm. Ameriprise Financial believes that the Fund is not currently the subject of, and that neither Ameriprise Financial nor any of its affiliates are the subject of, any pending legal, arbitration or regulatory proceedings that are likely to have a material adverse effect on the Fund or the ability of Ameriprise Financial or its affiliates to perform under their contracts with the Fund. Information regarding certain pending and settled legal proceedings may be found in the Fund’s shareholder reports and in the SAI. Additionally, Ameriprise Financial is required to make quarterly (10-Q), annual (10-K) and, as necessary, 8-K filings with the SEC on legal and regulatory matters that relate to Ameriprise Financial and its affiliates. Copies of these filings may be obtained by accessing the SEC website at sec.gov.
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Columbia Seligman Semiconductor and Technology ETF
Buying and Selling Fund Shares
Shares are issued or redeemed by the Fund at NAV per share only in Creation Units of 25,000 shares. As of December 31, 2022, the value of one Creation Unit of the Fund was $388,018.46.
Shares trade on the secondary market, which is where most retail investors will buy and sell shares. It is expected that only a limited number of institutional investors will purchase and redeem shares directly from the Fund. Thus, certain information in this prospectus is not relevant to most retail investors. For example, information about buying and redeeming Creation Units directly from the Fund and about transaction fees imposed on such purchases and redemptions is not relevant to most retail investors.
Except when aggregated in Creation Units, the Fund’s shares are not redeemable with the Fund. Additional information about the procedures regarding creation and redemption of Creation Units (including the cut-off times for receipt of creation and redemption orders) is included in the SAI.
Buying and Selling Fund Shares on the Secondary Market
The Fund issues or redeems its shares at NAV per share only in Creation Units and only to Authorized Participants (or APs). Most investors will buy and sell shares in secondary market transactions through brokers or other financial intermediaries, and therefore must have an account with them to buy and sell shares. Shares can be bought or sold through your financial intermediary throughout the trading day like shares of any publicly traded issuer. When buying or selling shares through a financial intermediary, you will incur customary brokerage commissions and charges, and you may pay some or all of the spread between the bid and the offered prices in the secondary market for shares. The price at which you buy or sell shares (i.e., the market price) may be more (a premium to) or less than (a discount to) the NAV of the shares. Unless imposed by your financial intermediary, there is no minimum dollar amount you must invest in the Fund and no minimum number of shares you must buy.
Shares of the Fund are listed on the Exchange under the symbol: SEMI
The Exchange is generally open Monday through Friday and is closed for weekends and the following holidays: New Year’s Day, Martin Luther King, Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Juneteenth National Independence Day, Independence Day, Labor Day, Thanksgiving Day, and Christmas Day.
For information about buying and selling shares on the Exchange or in the secondary markets, please contact your financial intermediary.
Book Entry. Shares are held in book entry form, which means that no stock certificates are issued. The Depository Trust Company (DTC), or its nominee, is the registered owner of all outstanding shares of the Fund and is recognized as the owner of all shares. Participants in DTC include securities brokers and dealers, banks, trust companies, clearing corporations and other institutions that directly or indirectly maintain a custodial relationship with DTC. As a beneficial owner of shares, you are not entitled to receive physical delivery of Fund Shares certificates or to have shares registered in your name, and you are not considered a registered owner of shares. Therefore, to exercise any right as an owner of shares, you must rely on the procedures of DTC and its participants. These procedures are the same as those that apply to any stocks that you hold in book entry or “street name” through your brokerage account. Your account information will be maintained by your financial intermediary, which will provide you with account statements, confirmations of your purchases and sales of shares, and tax information. Your financial intermediary also will be responsible for distributing income dividends and capital gain distributions and for ensuring that you receive shareholder reports and other communications from the Fund.
Share Trading Prices. The trading prices of the Fund’s shares may differ from the Fund’s daily NAV and can be affected by market forces of supply and demand for the Fund’s shares, the prices of the Fund’s investments, economic conditions and other factors.
Additional Information About Buying and Selling Fund Shares
Continuous Offering. Authorized Participants should be aware of certain legal risks unique to investors purchasing Creation Units directly from the Fund. Because shares may be issued on an ongoing basis, a “distribution” of shares could be occurring at any time. Certain activities that Authorized Participants perform with respect to the sale of shares could, depending on the circumstances, result in Authorized Participants being deemed to be a participant in
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Buying and Selling Fund Shares (continued)
the distribution, in a manner that could render Authorized Participants a statutory underwriter and subject Authorized Participants to the prospectus delivery and liability provisions of the Securities Act. For example, Authorized Participants could be deemed a statutory underwriter if Authorized Participants purchase Creation Units from the issuing Fund, break them down into the constituent shares, and sell those shares directly to customers, or if Authorized Participants choose to couple the creation of a supply of new shares with an active selling effort involving solicitation of secondary market demand for shares. Whether a person is an underwriter for purposes of the Securities Act depends upon all of the facts and circumstances pertaining to that person’s activities, and the examples mentioned here should not be considered a complete description of all the activities that could cause Authorized Participants to be deemed an underwriter.
Broker-dealer firms should also note that dealers who are not “underwriters” but are effecting transactions in shares, whether or not participating in the distribution of shares, are generally required to deliver a prospectus. This is because the prospectus delivery exemption in Section 4(3) of the Securities Act is not available in respect of such transactions as a result of Section 24(d) of the 1940 Act. As a result, broker-dealer firms should note that dealers who are not “underwriters” but are participating in a distribution (as opposed to engaging in ordinary secondary market transactions), and thus dealing with shares as part of an unsold allotment within the meaning of Section 4(3)(C) of the Securities Act, will be unable to take advantage of the prospectus delivery exemption provided by Section 4(3) of the Securities Act. For delivery of prospectuses to exchange members, the prospectus delivery mechanism of Rule 153 under the Securities Act is only available with respect to transactions on a national exchange.
Active Investors and Market Timing
The Board has determined not to adopt policies and procedures designed to prevent or monitor for frequent purchases and redemptions of the Fund’s shares because investors primarily transact in Fund shares on the secondary market. Frequent trading of shares on the secondary market does not disrupt portfolio management, increase the Fund’s trading costs, lead to realization of capital gains or otherwise harm Fund shareholders because these trades do not involve the issuance or redemption of Fund shares.
The Fund sells and redeems its shares at NAV only in Creation Units pursuant to the terms of a Participant Agreement between an Authorized Participant and the Distributor, and accepted by the Transfer Agent. With respect to such trades directly with the Fund to the extent effected in-kind (i.e., for securities), they generally would not cause the harmful effects that may result from frequent cash trades.
The Board recognizes that to the extent that the Fund allows or requires trades to be effected in whole or in part in cash, those trades could result in dilution to a Fund and increased transaction costs, which could negatively impact the Fund’s ability to achieve its investment objective. The Board also recognizes, however, that direct trading by Authorized Participants is critical to ensuring that the Fund’s shares trade at or close to NAV. Further, the Fund may employ fair valuation pricing to minimize the potential for dilution. Moreover, the Fund imposes transaction fees on purchases and redemptions of Creation Units reflecting the fact that the Fund’s costs increase in those circumstances. The Fund reserves the right to impose additional restrictions on disruptive, excessive or short-term purchases.
Distribution and Service Fees
The Board has approved, and the Fund has adopted, a distribution and service plan (the Plan) pursuant to Rule 12b-1 under the 1940 Act. Under the Plan, the Fund is authorized to pay distribution fees to the Distributor and other firms that provide distribution and shareholder services (Service Providers). If a Service Provider provides such services, the Fund may pay fees at an annual rate not to exceed 0.25% of average daily net assets, pursuant to Rule 12b-1 under the 1940 Act.
No distribution or service fees are currently paid by the Fund, and there are no current plans to impose these fees. Future payments may be made under the Plan without any further shareholder approval. In the event Rule 12b-1 fees are charged, over time they would increase the cost of an investment in the Fund.
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Columbia Seligman Semiconductor and Technology ETF
Buying and Selling Fund Shares (continued)
Determination of Net Asset Value
 FUNDamentals
NAV Calculation
The Fund calculates its NAV as follows:
NAV =  (Value of assets) – (Liabilities)
Number of outstanding shares
 FUNDamentals
Business days
A business day is any day that the New York Stock Exchange (NYSE) is open. A business day typically ends at the close of regular trading on the NYSE, usually at 4:00 p.m. Eastern time. If the NYSE is scheduled to close early, the business day will be considered to end as of the time of the NYSE’s scheduled close. For purposes of this section only, the Fund will not treat an intraday unscheduled disruption in NYSE trading or an intraday unscheduled closing as a close of regular trading on the NYSE for these purposes and will price its shares as of the regularly scheduled closing time for that day (typically, 4:00 p.m. Eastern time). Notwithstanding the foregoing, the NAV of Fund shares may be determined at such other time or times (in addition to or in lieu of the time set forth above) as the Fund’s Board may approve or ratify. On holidays and other days when the NYSE is closed, the Fund’s NAV is not calculated and the Fund does not accept buy or sell orders. However, the value of the Fund’s assets may still be affected on such days to the extent that the Fund holds foreign securities that trade on days that foreign securities markets are open.
Equity securities listed on an exchange are typically valued at the closing price or last trade on their primary exchange at the close of business of the NYSE. Securities without a readily available closing price or that are not listed on any exchange are typically valued at the mean between the closing bid and asked prices. Other equity securities, debt securities and other assets are valued differently. For instance, bank loans trading in the secondary market are fair valued unless market quotations are readily available, fixed income investments maturing in 60 days or less are valued primarily using the amortized cost method, unless this methodology results in a valuation that does not approximate the market value of these securities, and those maturing in excess of 60 days are valued based on prices obtained from a pricing service, if available (which may represent market values or fair values). Investments in other open-end funds are valued at their published NAVs. The value of each Fund’s portfolio securities is determined in accordance with the valuation policy approved by the Board.
If a market price is not readily available or is deemed not to reflect market value, the Investment Manager will determine the price of a portfolio security based on a determination of the security's fair value pursuant to the valuation policy approved by the Fund's Board. In addition, the Fund may use fair valuation to price securities that trade on a foreign exchange when a significant event has occurred after the foreign exchange closes but before the time at which the Fund's share price is calculated. Foreign exchanges typically close before the time at which Fund share prices are calculated, and may be closed altogether on some days when the Fund is open. Such significant events affecting a foreign security may include, but are not limited to: (1) corporate actions, earnings announcements, litigation or other events impacting a single issuer; (2) governmental action that affects securities in one sector or country; (3) natural disasters or armed conflicts affecting a country or region; or (4) significant domestic or foreign market fluctuations. The Fund uses various criteria in determining whether a foreign security's market price is readily available and reflective of market value and, if not, the fair value of the security.
Fair valuation may have the effect of reducing stale pricing arbitrage opportunities presented by the pricing of Fund shares. However, when the Investment Manager uses fair valuation to price equity securities, it may value those securities higher or lower than another fund would have priced the security. Also, the use of fair valuation may cause the Fund's performance to diverge to a greater degree from the performance of various benchmarks used to
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Buying and Selling Fund Shares (continued)
compare the Fund's performance because benchmarks generally do not use fair valuation techniques. Because of the judgment involved in fair valuation decisions, there can be no assurance that the value ascribed to a particular security is accurate.
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Distributions and Taxes
Distributions to Shareholders
A fund can make money two ways:
It can earn income on its investments. Examples of fund income are interest paid on money market instruments and dividends paid on common stocks.
A fund can also have capital gains if the value of its investments increases. While a fund continues to hold an investment, any gain is generally unrealized. If the fund sells an investment, it generally will realize a capital gain if it sells that investment for a higher price than its adjusted cost basis, and will generally realize a capital loss if it sells that investment for a lower price than its adjusted cost basis. Capital gains and losses are either short-term or long-term, depending on whether the fund holds the securities for one year or less (short-term) or more than one year (long-term).
Funds make payments of fund earnings to shareholders, distributing them among all shareholders of the fund. As a shareholder, you are entitled to your portion of a fund's distributed income, including capital gains. Reinvesting your distributions buys you more shares of a fund which lets you take advantage of the potential for compound growth. Putting the money you earn back into your investment means it, in turn, may earn even more money (or be exposed to additional losses, if the fund earns a negative return). Over time, the power of compounding has the potential to significantly increase the value of your investment. There is no assurance, however, that you'll earn more money if you reinvest your distributions rather than receive them in cash.
Brokers may make available to their customers who own shares the DTC book-entry dividend reinvestment service. To determine whether the dividend reinvestment service is available and whether there is a commission or other charge for using this service, consult your broker. Brokers may require Fund shareholders to adhere to specific procedures and timetables. If this service is available and used, dividend distributions of both income and net realized gains will be automatically reinvested in additional whole shares of the distributing Fund purchased in the secondary market. Without this service, investors would receive their distributions in cash.
The Fund intends to pay out, in the form of distributions to shareholders, a sufficient amount of its income and gains so that the Fund will qualify for treatment as a regulated investment company and generally will not have to pay any federal income or excise tax. The Fund generally intends to distribute any net realized capital gain (whether long-term or short-term gain) at least once a year. Normally, the Fund will declare and pay distributions of net investment income according to the following schedule:
    
Declaration and Distribution Schedule
Declarations Annually
Distributions Annually
The Fund may declare or pay distributions of net investment income more frequently.
Each time a distribution is made, the NAV per share is reduced by the amount of the distribution.
The Fund generally pays cash distributions within five business days after the distribution was declared. If you sell all of your shares after the record date, but before the payment date, for a distribution, you'll normally receive that distribution in cash within five business days after the sale was made.
Unless you are a tax-exempt investor or holding Fund shares through a tax-advantaged account (such as a 401(k) plan or IRA), you should consider avoiding buying Fund shares shortly before the Fund makes a distribution (other than distributions of net investment income that are declared daily) of net investment income or net realized capital gain, because doing so can cost you money in taxes to the extent the distribution consists of taxable income or gains. This is because you will, in effect, receive part of your purchase price back in the distribution. This is known as “buying a dividend.” To avoid “buying a dividend,” before you invest check the Fund's distribution schedule, which is available at the Funds' website and/or by calling 800.426.3750.
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Distributions and Taxes (continued)
Taxes
You should be aware of the following considerations applicable to the Fund:
The Fund intends to qualify and to be eligible for treatment each year as a regulated investment company. A regulated investment company generally is not subject to tax at the fund level on income and gains from investments that are distributed to shareholders. However, the Fund's failure to qualify for treatment as a regulated investment company would result in Fund-level taxation, and consequently, a reduction in income available for distribution to you and in the NAV of your shares. Even if the Fund qualifies for treatment as a regulated investment company, the Fund may be subject to federal excise tax on certain undistributed income or gains.
Otherwise taxable distributions generally are taxable to you when paid, whether they are paid in cash or automatically reinvested in additional Fund shares. Dividends paid in January are deemed paid on December 31 of the prior year if the dividend was declared and payable to shareholders of record in October, November, or December of such prior year.
Distributions of the Fund's ordinary income and net short-term capital gain, if any, generally are taxable to you as ordinary income. Distributions of the Fund's net long-term capital gain, if any, generally are taxable to you as long-term capital gain. Whether capital gains are long-term or short-term is determined by how long the Fund has owned the investments that generated them, rather than how long you have owned your shares. Certain events may require the Fund to sell significant amounts of appreciated securities and make large dividends relative to the Fund’s NAV. Such events may include portfolio rebalancing or fund mergers. The Fund generally provides estimates of expected capital gain dividends (if any) prior to the distribution on columbiathreadneedleus.com/etfs.
From time to time, a distribution from the Fund could constitute a return of capital. A return of capital is a return of an amount of your original investment and is not a distribution of income or capital gain from the Fund. Therefore, a return of capital is not taxable to you so long as the amount of the distribution does not exceed your tax basis in your Fund shares. A return of capital reduces your tax basis in your Fund shares, with any amounts exceeding such basis generally taxable as capital gain.
If you are an individual and you meet certain holding period and other requirements for your Fund shares, a portion of your distributions may be treated as “qualified dividend income” taxable at the lower net long-term capital gain rates instead of the higher ordinary income rates. Qualified dividend income is income attributable to the Fund's dividends received from certain U.S. and foreign corporations, as long as the Fund meets certain holding period and other requirements for the stock producing such dividends.
Certain high-income individuals (as well as estates and trusts) are subject to a 3.8% tax on net investment income. For individuals, the 3.8% tax applies to the lesser of (1) the amount (if any) by which the taxpayer's modified adjusted gross income exceeds certain threshold amounts or (2) the taxpayer's “net investment income.”
  Net investment income generally includes for this purpose dividends, including any capital gain dividends, paid by the Fund, and net gains recognized on the sale, redemption or exchange of shares of the Fund.
Certain derivative instruments when held in the Fund's portfolio subject the Fund to special tax rules, the effect of which may be to, among other things, accelerate income to the Fund, defer Fund losses, cause adjustments in the holding periods of Fund portfolio securities, or convert capital gains into ordinary income, short-term capital losses into long-term capital losses or long-term capital gains into short-term capital gains. These rules could therefore affect the amount, timing and/or character of distributions to shareholders.
Generally, a Fund realizes a capital gain or loss on an option when the option expires, or when it is exercised, sold or otherwise terminated. However, if an option is a “section 1256 contract,” which includes most traded options on a broad-based index, and the Fund holds such option at the end of its taxable year, the Fund is deemed to sell such option at fair market value at such time and recognize any gain or loss thereon, which is generally deemed to be 60% long-term and 40% short-term capital gain or loss, as described further in the SAI.
Income and proceeds received by the Fund from sources within foreign countries may be subject to foreign taxes. If at the end of the taxable year more than 50% of the value of the Fund's assets consists of securities of foreign corporations, and the Fund makes a special election, you will generally be required to include in your income for
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Columbia Seligman Semiconductor and Technology ETF
Distributions and Taxes (continued)
  U.S. federal income tax purposes your share of the qualifying foreign income taxes paid by the Fund in respect of its foreign portfolio securities. You may be able to claim a foreign tax credit or deduction in respect of this amount, subject to certain limitations. There is no assurance that the Fund will make this election for a taxable year, even if it is eligible to do so.
A sale, redemption or exchange of Fund shares is a taxable event. This includes redemptions where you are paid in securities. Your sales, redemptions and exchanges of Fund shares, including those paid in securities or other instruments, usually will result in a taxable capital gain or loss to you, equal to the difference between the amount you receive for your shares (or are deemed to have received in the case of exchanges) and your adjusted tax basis in the shares, which is generally the amount you paid (or are deemed to have paid in the case of exchanges) for them. Any such capital gain or loss generally will be long-term capital gain or loss if you have held your Fund shares for more than one year at the time of sale or exchange. In certain circumstances, capital losses may be converted from short-term to long-term; in other circumstances, capital losses may be disallowed under the “wash sale” rules.
Your broker will be responsible for furnishing tax reporting information for Fund shares held in a nonqualified account, shareholder reports, and other communications from the Fund. For sales or exchanges of Fund shares acquired in a nonqualified account after 2011, your broker is required to report basis and holding period information to you and the IRS. Your broker may offer a choice of basis calculation methods. Contact your broker to determine which basis methods are available for your account.
The Fund or, in the case of sales of Fund shares in the secondary market, your broker, will generally be required by federal law to withhold tax on any distributions and proceeds paid to you if you have not provided a correct taxpayer identification number (TIN) or have not certified to the Fund or its agent, or your broker, as the case may be, that withholding does not apply.
For Authorized Participants Purchasing and Redeeming in Creation Units: An Authorized Participant that exchanges equity securities for one or more Creation Units will generally recognize a gain or a loss on the exchange. The gain or loss will be equal to the difference between (i) the market value of the Creation Unit(s) at the time and, (ii) the exchanger’s aggregate basis in the securities surrendered plus (or minus) the Cash Component paid (or received). A person who redeems one or more Creation Units for equity securities will generally recognize a gain or loss equal to the difference between (i) the exchanger’s basis in the Creation Unit(s) and, (ii) the aggregate market value of the securities received plus (or minus) the Cash Component received (or paid). The IRS, however, may assert that a loss realized upon an exchange of securities for Creation Unit(s) cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in economic position. Persons exchanging securities should consult their own tax advisors with respect to whether wash sale rules apply and when a loss might be deductible. Any capital gain or loss realized upon a redemption of one or more Creation Units is generally treated as long-term capital gain or loss if the Creation Unit(s) have been held for more than one year and as short-term capital gain or loss if they have been held for one year or less. If you purchase or redeem Creation Units, you will be sent a confirmation statement showing how many shares you purchased or sold and at what price.
 FUNDamentals
Taxes
The information provided above is only a summary of how U.S. federal income taxes may affect your investment in the Fund. It is not intended as a substitute for careful tax planning. Your investment in the Fund may have other tax implications. It does not apply to certain types of investors who may be subject to special rules, including foreign or tax-exempt investors or those holding Fund shares through a tax-advantaged account, such as a 401(k) plan or IRA. Please see the SAI for more detailed tax information. You should consult with your own tax advisor about the particular tax consequences to you of an investment in the Fund, including the effect of any foreign, state and local taxes, and the effect of possible changes in applicable tax laws.
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Columbia Seligman Semiconductor and Technology ETF
Financial Highlights
The financial highlights table is intended to help you understand the Fund’s financial performance for the past five fiscal years or, if shorter, the Fund’s period of operations. Certain information reflects financial results for a single Fund share. The total return in the table represents the rate that an investor would have earned (or lost) on an investment in the Fund assuming all dividends and distributions had been reinvested. This information has been audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, whose report, along with the Fund’s financial statements, is included in the Fund’s annual report, which is available upon request.
    
  Year Ended
October 31,
2022 (a)
Per share data  
Net asset value, beginning of year $20.00
Income (loss) from investment operations:  
Net investment income 0.00(b)
Net realized and unrealized loss (5.12)
Total from investment operations (5.12)
Net asset value, end of year $14.88
Total Return at NAV (25.60)%
Total Return at Market (25.80)%
Ratios to average net assets:  
Total gross expenses(c) 0.75%(d)
Total net expenses(c)(e) 0.75%(d)
Net investment income 0.09%(d)
Supplemental data  
Net assets, end of year (in thousands) $12,278
Portfolio turnover 19%
  
(a) The Fund commenced operations on March 29, 2022. Per share data and total return reflect activity from that date.
(b) Rounds to zero.
(c) In addition to the fees and expenses that the Fund bears directly, the Fund indirectly bears a pro rata share of the fees and expenses of any other funds in which it invests. Such indirect expenses are not included in the Fund’s reported expense ratios.
(d) Annualized
(e) Total net expenses include the impact of certain fee waivers/expense reimbursements made by the Investment Manager and certain of its affiliates, if applicable.
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Columbia Seligman Semiconductor and Technology ETF
290 Congress Street
Boston, MA 02210
Additional Information About the Fund
Additional information about the Fund’s investments is available in the Fund’s annual and semiannual reports to shareholders. In the annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund’s performance during its last fiscal year. The SAI also provides additional information about the Fund and its policies. The SAI, which has been filed with the SEC, is legally part of this prospectus (incorporated by reference). To obtain these documents free of charge, to request other information about the Fund and to make shareholder inquiries, please contact the Fund as follows:
By Mail:  Columbia Funds
290 Congress Street
Boston, MA 02210
By Telephone: 800.426.3750
Online: columbiathreadneedleus.com/etfs
Reports and other information about the Fund are also available in the EDGAR Database on the SEC’s website at http://www.sec.gov. You can receive copies of this information, for a duplication fee, by electronic request at the following e-mail address: [email protected].
The investment company registration number of Columbia ETF Trust I, of which the Fund is a series, is 811-22736.
Columbia Threadneedle Investments is the global brand name of the Columbia and Threadneedle group of companies.
© 2023 Columbia Management Investment Advisers, LLC. All rights reserved.
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