As filed with the Securities and Exchange Commission on February 28, 2023.

Post-Effective Amendment No. 31

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Amendment No. 32

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☒        On March 1, 2023 pursuant to paragraph (b)

This Post-Effective Amendment relates solely to the Registrant’s Columbia Diversified Fixed Income Allocation ETF, Columbia International ESG Equity Income ETF, Columbia Multi-Sector Municipal Income ETF, Columbia Research Enhanced Core ETF, Columbia Research Enhanced Value ETF, Columbia Seligman Semiconductor and Technology ETF, Columbia Short Duration Bond ETF, and Columbia U.S. ESG Equity Income ETF series. Information contained in the Registrant’s Registration Statement relating to any other series of the Registrant is neither amended nor superseded hereby.

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Year by Year Total Return (%) as of December 31 Each Year	Best and Worst Quarterly Returns During the Period Shown in the Bar Chart
	Best	2nd Quarter 2020	6.77%
	Worst	2nd Quarter 2022	-8.95%

	Inception Date	1 Year	5 Years	Life of Fund
At NAV	10/12/2017
returns before taxes		-15.86%	0.27%	0.28%
returns after taxes on distributions		-16.99%	-0.98%	-0.97%
returns after taxes on distributions and sale of Fund shares		-9.37%	-0.28%	-0.27%
Beta Advantage® Multi-Sector Bond Index (reflects no deductions for fees, expenses or taxes)		-16.41%	0.29%	0.34%
Bloomberg U.S. Aggregate Bond Index (reflects no deductions for fees, expenses or taxes)		-13.01%	0.02%	0.09%

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Portfolio Management		Title		Role with Fund		Managed Fund Since
Gene Tannuzzo, CFA		Managing Director and Global Head of Fixed Income		Lead Portfolio Manager		2017
David Janssen, CFA		Portfolio Manager		Portfolio Manager		2017

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 50,000 shares, called Creation Units. Creation Units are issued and redeemed typically for an in-kind basket of securities. 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.

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Investment Objective

Beta Advantage^® Multi-Sector Approach to Debt Market Investing. The Index reflects a rules-based multi-sector strategic beta approach to measuring the performance of the debt market through representation of six segments of the debt market in the Index, each focused on yield, quality, and liquidity of the particular segment. The Index, and therefore the Fund, will have exposure to the following six segments of the debt market (% amount noted is the Index’s allocation to the particular segment at index rebalancing and reconstitution as described below): U.S. Treasury securities (10%); global ex-U.S. treasury securities (10%); U.S. agency mortgage-backed securities (15%); U.S. corporate investment grade bonds (15%); U.S. corporate high yield bonds (30%); and emerging markets sovereign and quasi-sovereign debt (20%). The Index’s allocation to each of the six segments of the debt market, represented by six sub-index models, is fixed as of each Index rebalancing and reconstitution, but may vary due to the performance of each segment between these events. The number of securities in each of the six sub-index models and the Index as a whole noted below are as of January 31, 2023 and are subject to change. The six sub-index models, each as discussed below, will generate all of the component securities of the Index. Each sub-index model is market value-weighted except for the Global Ex-U.S. Treasury Securities Sector sub-index model, which is equal-weighted.

Beta Advantage^® Strategy to Investing in the U.S. Treasury Securities Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those U.S. Treasury securities included in the Bloomberg Barclays US Treasury Total Return Index that meet the following criteria: have a remaining maturity of greater than 7 years, are rated investment grade, are U.S. dollar denominated, have a fixed-rate coupon, are non-convertible, and have $250 million or more of outstanding face value. At January 31, 2023, this sub-index model held 86 securities.

Beta Advantage^® Strategy to Investing in the Global Ex-U.S. Treasury Securities Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those securities included in the Bloomberg Barclays Global Treasury Ex-US Total Return Index (which is comprised of fixed rate, local currency, investment grade sovereign debt of countries outside the U.S.) that meet the following criteria: have a remaining maturity of between and including 7 to 12 years and a yield greater than 0.00% that are issued by the following countries: Australia, Canada, France, Germany, Italy, Japan, New Zealand, Norway, Sweden, Switzerland, and the United Kingdom. From these securities, the single largest debt instrument is selected (by amount outstanding) from each country, equally weighted per country. At January 31, 2023, this sub-index model held 11 securities.

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Beta Advantage^® Strategy to Investing in the U.S. Agency Mortgage-Backed Securities Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those securities included in the Bloomberg Barclays US MBS Total Return Index (which is comprised of U.S. agency mortgage pass-through securities backed by pools of mortgages and issued by the following U.S. government-sponsored enterprises: Federal National Mortgage Association (FNMA) and Federal Home Loan Mortgage Corporation (FHLMC)) that meet the following criteria: have a 30-year fixed-rate program, an issuance date less than 1,000 days, and that are denominated in U.S. dollars. At January 31, 2023, this sub-index model held 253 securities.

Beta Advantage^® Strategy to Investing in the U.S. Corporate Investment Grade Debt Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those securities included in the Bloomberg Barclays US Corporate Total Return Index (which is comprised of investment grade, fixed-rate, taxable, U.S. dollar denominated debt with $250 million or more of par amount outstanding, issued by U.S. and non-U.S. industrial companies, utilities, and financial institutions) that meet the following criteria: have a remaining maturity of between and including 5 to 15 years, a credit rating between and including BAA1 and BAA3 using the Bloomberg Barclays index rating methodology, and an issuance date not greater than 1,000 days. The two largest issues from each issuer are selected based on amount outstanding. At January 31, 2023, this sub-index model held 551 securities.

Beta Advantage^® Strategy to Investing in the U.S. Corporate High Yield Debt Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those securities included in the Bloomberg Barclays US Corporate High Yield Total Return Index (which is comprised of publicly issued U.S. dollar denominated, non-investment grade, fixed-rate, taxable corporate bonds) that meet the following criteria: have a (non-investment grade) credit rating above B3 using the Bloomberg index rating methodology, an outstanding face amount greater than $800 million, remaining maturity of less than 14 years, and issued within the past 5 years. Pay-in-kind (PIK) and partial PIK instruments are excluded from this sub-index model. The two largest issues from each issuer are selected based on amount outstanding, subject to a 2% issuer cap based on market value. At January 31, 2023, this sub-index model held 246 securities.

Beta Advantage^® Strategy to Investing in the Emerging Markets Sovereign and Quasi-Sovereign Debt Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those securities included in the Bloomberg Barclays Emerging Markets USD Aggregate Total Return Index (which is comprised of fixed-rate sovereign and quasi-sovereign debt of emerging market countries rated investment grade and non-investment grade) that meet the following criteria, with corporate issuers being excluded: have a credit rating between and including BAA1 and BA3 using the Bloomberg Barclays index rating methodology, remaining maturity of between and including 5 to 15 years, and a minimum amount outstanding of at least $2 billion. The two largest issues from each issuer are selected based on amount outstanding, subject to a maximum 10% country weighting (based on market value). At January 31, 2023, this sub-index model held 58 securities.

As noted above, the six sub-index models will generate all of the component securities of the Index. Columbia Management expects to utilize a “representative sampling” strategy whereby the Fund invests in only some of the component securities of the Index that, collectively, are believed by the Investment Manager to generally reflect the same risk and return characteristics of the Index. As such, the Fund may not track the Index with the same degree of accuracy as would a fund replicating (or investing in) the entire Index. Through its representative sampling investment technique, the Fund expects to typically hold 500-800 holdings, which is a subset of the total number of holdings in the Index, which, as of January 31, 2023, had 1,205 holdings. There may be instances in which the Fund may overweight (or underweight) an Index holding, purchase (or sell) instruments not in the Index as a substitute for one or more securities in the Index or utilize various combinations of other available investment techniques in seeking to

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An investment in the Fund involves risks, including Interest Rate Risk, Credit Risk, Passive Investment Risk, Market Risk, and Correlation/Tracking Error 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.

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 is heightened in times of market stress, including at both the Fund share level and at the Fund holdings level.

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performance of the Index, which is an indexing strategy that involves investing in only some of the components of the Index that collectively have an investment profile similar to that of the Index. Because the Fund uses a representative sampling approach, the Fund may not track the Index with the same degree of accuracy as would an investment vehicle replicating the entire Index. In addition, the Fund may invest in securities or other instruments not included in the Index. The Fund may take or refrain from taking investment positions for various reasons, such as tax efficiency purposes, or to comply with regulatory restrictions, which may negatively affect the Fund’s correlation with the Index. The Fund may also be subject to large movements of assets into and out of the Fund, potentially resulting in the Fund being over- or under-exposed to certain components of the Index and may be impacted by Index reconstitutions and Index rebalancing events. Additionally, the Fund's foreign investments may trade on markets that may not be open on the same day or at the same time as the Fund, which may cause a difference between the changes in the daily performance of the Fund and changes in the level of the Index. Furthermore, the Fund may need to execute currency trades that due to regulatory, legal and operational constraints will occur at a later date than the trading of the related security. Currency holdings may be valued at a different time and at different rates than that used by the Index. Holding cash balances may detract from the Fund’s ability to track the Index. In addition, the Fund’s NAV may deviate from the Index if the Fund fair values a portfolio security at a price other than the price used by the Index for that security. The Fund also bears management and other expenses and transaction costs in trading securities or other instruments, which the Index does not bear. The Fund, unlike the Index, is subject to regulatory requirements that can limit the Fund’s investments relative to what the Index can hold. The Fund, unlike the Index, is subject to Office of Foreign Assets Control and other regulatory restrictions, including, for example, restrictions on the ability of the Fund to invest in or hold certain securities. If the Fund is restricted from investing in or holding a security that was a component of the Index, and the Index did not remove such security, timely or at all, the Fund’s ability to track the Index could be negatively impacted. Accordingly, the Fund’s performance will likely fail to match the performance of the Index, after taking expenses into account, as well as regulatory limitations. Any of these factors could decrease correlation between the performance of the Fund and the Index and may hinder the Fund’s ability to meet its investment objective. It is not possible to invest directly in an index.

Credit Risk. Credit risk is the risk that the value of debt instruments may decline if the borrower or the issuer thereof defaults or otherwise becomes unable or unwilling, or is perceived to be unable or unwilling, to honor its financial obligations, such as making payments to the Fund when due. Various factors could affect the actual or perceived willingness or ability of the borrower or the issuer to make timely interest or principal payments, including changes in the financial condition of the borrower or the issuer or in general economic conditions. Credit rating agencies, such as S&P Global Ratings, Moody’s, Fitch, DBRS and KBRA, assign credit ratings to certain debt instruments to indicate their credit risk. A rating downgrade by such agencies can negatively impact the value of such instruments. Lower-rated or unrated instruments held by the Fund may present increased credit risk as compared to higher-rated instruments. Non-investment grade debt instruments may be subject to greater price fluctuations and are more likely to experience a default than investment grade debt instruments and therefore may expose the Fund to increased credit risk. If the Fund purchases unrated instruments, or if the ratings of instruments held by the Fund are lowered after purchase, the Fund will depend on analysis of credit risk more heavily than usual. If the issuer of a loan declares bankruptcy or is declared bankrupt, there may be a delay before the Fund can act on the collateral securing the loan, which may adversely affect the Fund. Further, there is a risk that a court could take action with respect to a loan that is adverse to the holders of the loan. Such actions may include invalidating the loan, the lien on the collateral, the priority status of the loan, or ordering the refund of interest previously paid by the borrower. Any such actions by a court could adversely affect the Fund’s performance. A default or expected default of a loan could also make it difficult for the Fund to sell the loan at a price approximating the value previously placed on it. In order to enforce its rights in the event of a default, bankruptcy or similar situation, the Fund may be required to retain legal or

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Depositary Receipts Risk. Depositary receipts are receipts issued by a bank or trust company reflecting ownership of underlying securities issued by foreign companies. Some foreign securities are traded in the form of American Depositary Receipts and/or Global Depositary Receipts. Depositary receipts involve risks similar to the risks associated with investments in foreign securities, including those associated with an issuer’s (and any of its related companies’) country of organization and places of business operations, which may be related to the particular political, regulatory, economic, social 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 and fluctuations in such country’s currency, as well as market risk tied to the underlying foreign company. In addition, holders of depositary receipts may have limited voting rights, may not have the same rights afforded to stockholders of a typical domestic company in the event of a corporate action, such as an acquisition, merger or rights offering, and may experience difficulty in receiving company stockholder communications. There is no guarantee that a financial institution will continue to sponsor a depositary receipt, or that a depositary receipt will continue to trade on an exchange, either of which could adversely affect the liquidity, availability and pricing of the depositary receipt. Changes in foreign currency exchange rates will affect the value of depositary receipts and, therefore, may affect the value of your investment in the Fund. To the extent that the exchange price of a depositary receipt differs from the local price of the underlying security used by the Index, the Fund may be prevented from fully achieving its investment objective of tracking the performance of the Index.

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. In these circumstances, the Fund may be unable to rebalance and reconstitute its portfolio, may be unable to accurately price its investments, may incur substantial trading losses and/or may be prevented from sufficiently tracking the performance of the Index.

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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 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. The performance of the Fund may also be negatively affected by fluctuations in a foreign currency's strength or weakness relative to the U.S. dollar, particularly to the extent the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar. 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. Additionally, the Fund’s foreign investments may trade in markets that may not be open on the same day or at the same time as the Fund, or foreign markets may close after the Fund has calculated its NAV for a given business day, which may cause a difference in the market price of such foreign securities and the value attributed to such securities by the Fund which in turn may result in 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.

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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.

Index Methodology and Provider Risk. The Fund seeks performance that corresponds to the performance of the Index. There is no guarantee or assurance that the Index will achieve high, or even positive, returns. The Index may underperform more traditional indices. In turn, the Fund could lose value while other indices or measures of market performance increase in value or performance. In addition, the Fund may be subject to the risk that the Index Provider may not follow its stated methodology for construction or errors may be made in Index computation, construction, reconstitution and rebalancing, despite any Index Provider procedures designed to prevent such

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occurrences and due diligence conducted by the Investment Manager. Errors may result in a negative performance impact to the Fund and its shareholders. The decision of whether to remove a security from the tracking index is made by an independent index provider who is not affiliated with the Fund or the Investment Manager.

Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if interest rates rise, the values of debt instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund receives from it but will generally affect the value of your investment in the Fund. Changes in interest rates may also affect the liquidity of the Fund’s investments in debt instruments. In general, the longer the maturity or duration of a debt instrument, the greater its sensitivity to changes in interest rates. Interest rate declines also may increase prepayments of debt obligations, which, in turn, would increase prepayment risk (the risk that the Fund will have to reinvest the money received in securities that have lower yields). Very low or negative interest rates may impact the Fund’s yield and may increase the risk that, if followed by rising interest rates, the Fund’s performance will be negatively impacted. The Fund is subject to the risk that the income generated by its investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates. Higher periods of inflation could lead such authorities to raise interest rates. Such actions may negatively affect the value of debt instruments held by the Fund, resulting in a negative impact on the Fund's performance and NAV. Debt instruments with floating coupon rates are typically less sensitive to interest rate changes, but these debt instruments may decline in value if their coupon rates do not rise as much as, or keep pace with, yields on such types of debt instruments. Because rates on certain floating rate loans and other debt instruments reset only periodically, changes in interest rates (and particularly sudden and significant changes) can be expected to cause fluctuations in the Fund’s NAV. Any interest rate increases could cause the value of the Fund’s investments in debt instruments to decrease. Rising interest rates may prompt redemptions from the Fund, which may force the Fund to sell investments at a time when it is not advantageous to do so, which could result in losses.

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/or wider bid/ask spreads than those experienced by other ETFs.

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purchased by the Fund may later become illiquid, particularly in times of overall economic distress. Changing regulatory, market or other conditions or environments (for example, the interest rate or credit environments) may also adversely affect the liquidity and the price of the Fund's investments. Judgment plays a larger role in valuing illiquid or less liquid investments as compared to valuing liquid or more liquid investments. Price volatility may be higher for illiquid or less liquid investments as a result of, for example, the relatively less frequent pricing of such securities (as compared to liquid or more liquid investments). Generally, the less liquid the market at the time the Fund sells a portfolio investment, the greater the risk of loss or decline of value to the Fund. Overall market liquidity and other factors can lead to an increase in redemptions of creation units, which may negatively impact Fund performance and NAV, including, for example, if the Fund is forced to sell investments in a down market. In certain circumstances, the Fund might not be able to dispose of certain holdings quickly or at fair prices, preventing the Fund from tracking the Index. Foreign securities can present enhanced liquidity risks, including as a result of less developed custody, settlement or other practices of foreign markets. In addition, in stressed market conditions, the market for Fund shares may become less liquid. Deterioration in the liquidity of Fund shares may adversely impact the liquidity of the Fund's underlying portfolio securities. These adverse impacts on the liquidity of Fund shares and on the liquidity of the Fund's underlying portfolio securities could in turn lead to 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.

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. 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/or 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

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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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Passive Investment Risk. The Fund is not actively managed and may be affected by a general decline in market segments related to its Index’s investment exposures. The Fund invests in securities or instruments included in, or believed by the Investment Manager to be representative of the Index regardless of their investment merits. The Fund does not seek temporary defensive positions when markets decline or appear overvalued.

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 shares. In addition, secondary market investors will also incur the cost of the difference between the price that an investor is willing to pay for Fund shares (the bid price) and the price at which an investor is willing to sell Fund shares (the ask price). This difference in bid and ask prices is often referred to as the “spread” or “bid/ask spread.” The bid/ask spread varies over time for Fund shares based on trading volume and market liquidity, and is generally lower if the Fund’s shares have more trading volume and market liquidity and higher if the Fund’s shares have little trading volume and market liquidity. Further, increased market volatility may cause widening of bid/ask spreads.

Sector Risk. At times, the Fund may have a significant portion of its assets invested in securities of companies conducting business in a related group of industries within one or more economic sectors. The Fund will concentrate its investments in issuers conducting business in a related group of industries to approximately the same extent as the Index. Companies in the same sector may be similarly affected by economic, regulatory, political or market

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events or conditions, which may make the Fund more vulnerable to unfavorable developments in that group of industries or economic sector than funds that invest more broadly. Generally, the more broadly the Fund invests, the more it spreads risk and potentially reduces the risks of loss and volatility.

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 typically for an in-kind basket of securities. 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 50,000 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 brokers.

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The Fund may enter into derivative transactions. Derivatives are financial contracts whose values are, for example, based on (or “derived” from) traditional securities (such as a stock or bond), assets (such as a commodity like gold or a foreign currency), reference rates (such as the Secured Overnight Financing Rate (commonly known as SOFR) or the London Interbank Offered Rate (commonly known as LIBOR)) or market indices (such as the Standard & Poor’s 500® Index). The use of derivatives is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. Derivatives involve special risks and may result in losses or may limit the Fund’s potential gain from favorable market movements. Derivative strategies often involve leverage, which may exaggerate a loss, potentially causing the Fund to lose more money than it would have lost had it invested in the underlying security or other asset directly. The values of derivatives may move in unexpected ways, especially in unusual market conditions, and may result in increased volatility in the value of the derivative and/or the Fund’s shares, among other consequences.  The use of derivatives may also increase the amount of taxes payable by shareholders holding shares in a taxable account. Other risks arise from the Fund’s potential inability to terminate or to sell derivative positions. A liquid secondary market may not always exist for the Fund’s derivative positions at times when the Fund might wish to terminate or to sell such positions. Over-the-counter instruments (investments not traded on an exchange) may be illiquid, and transactions in derivatives traded in the over-the-counter market are subject to the risk that the other party will not meet its obligations. The use of derivatives also involves the risks of mispricing or improper valuation and that changes in the value of the derivative may not correlate perfectly with the underlying security, asset, reference rate or index. The Fund also may not be able to find a suitable derivative transaction counterparty, and thus may be unable to engage in derivative transactions when it is deemed favorable to do so, or at all. U.S. federal legislation has been enacted that provides for new clearing, margin, reporting and registration requirements for participants in the derivatives market. These changes could restrict and/or impose significant costs or other burdens upon the Fund’s participation in derivatives transactions. The U.S. government and the European Union (and some other jurisdictions) have enacted regulations and similar requirements that prescribe clearing, margin, reporting and registration requirements for participants in the derivatives market. These requirements are evolving and their ultimate impact on the Fund remains unclear, but such impact could include restricting and/or imposing significant costs or other burdens upon the Fund’s participation in derivatives transactions. Additionally, in October 2020, the SEC adopted new regulations governing the use of derivatives by registered investment companies. Rule 18f-4, among other things, requires a fund that invests in derivative instruments beyond a specified limited amount to apply a value-at-risk-based limit to its portfolio and establish a comprehensive derivatives risk management program. As of the date of this prospectus, the Fund is required to maintain a comprehensive derivatives risk management program under Rule 18f-4 which could have an adverse impact on the Fund’s performance and ability to implement its investment strategies as it has historically. For more information on the risks of derivative investments and strategies, see the SAI.

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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 Management		Title		Role with Fund		Managed Fund Since
Gene Tannuzzo, CFA		Managing Director and Global Head of Fixed Income		Lead Portfolio Manager		2017
David Janssen, CFA		Portfolio Manager		Portfolio Manager		2017

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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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Shares are issued or redeemed by the Fund at NAV per share only in Creation Units of 50,000 shares. As of December 31, 2022, the value of one Creation Unit of the Fund was $864,647.10.

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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.

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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.

NAV Calculation

The Fund calculates its NAV as follows:

NAV =  (Value of assets) – (Liabilities)
Number of outstanding shares

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

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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 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 to Shareholders

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:

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 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.

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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.

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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Information regarding how often the shares of the Fund traded on the Exchange at a price above (at a premium) or below (at a discount) the NAV of the Fund during the past four calendar quarters can be found at the Internet address noted below.

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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	2021	2020	2019	2018
Per share data
Net asset value, beginning of year	$21.29	$21.36	$20.78	$18.86	$19.94
Income (loss) from investment operations:
Net investment income	0.54	0.50	0.60	0.72	0.67
Net realized and unrealized gain (loss)	(4.48)	(0.04)	0.57	1.91	(1.13)
Total from investment operations	(3.94)	0.46	1.17	2.63	(0.46)
Less distributions to shareholders:
Net investment income	(0.55)	(0.53)	(0.59)	(0.71)	(0.62)
Total distribution to shareholders	(0.55)	(0.53)	(0.59)	(0.71)	(0.62)
Net asset value, end of year	$16.80	$21.29	$21.36	$20.78	$18.86
Total Return at NAV	(18.80)%	2.16%	5.71%	14.21%	(2.32)%
Total Return at Market	(18.87)%	1.97%	5.69%	14.78%	(2.68)%
Ratios to average net assets:
Total gross expenses(a)	0.28%(b)	0.28%	0.28%	0.28%	0.28%(b)
Total net expenses(a)(c)	0.28%(b)	0.28%	0.28%	0.28%	0.24%(b)
Net investment income	2.78%	2.34%	2.87%	3.62%	3.49%
Supplemental data
Net assets, end of year (in thousands)	$572,031	$1,215,511	$536,060	$193,227	$84,884
Portfolio turnover	198%	171%	156%	171%	140%

(a)	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.
(b)	The ratio includes less than 0.01% attributed to overdraft expense, which is outside the Unitary Fee (as defined in Note 3).

(c)	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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By Telephone: 800.426.3750

© 2023 Columbia Management Investment Advisers, LLC. All rights reserved.

PRO290_10_N01_(03/23)

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Year by Year Total Return (%) as of December 31 Each Year	Best and Worst Quarterly Returns During the Period Shown in the Bar Chart
	Best	4th Quarter 2022	4.21%
	Worst	1st Quarter 2022	-6.66%

	Inception Date	1 Year	Life of Fund
At NAV	10/10/2018
returns before taxes		-8.67%	2.33%
returns after taxes on distributions		-9.32%	1.45%
returns after taxes on distributions and sale of Fund shares		-5.13%	1.43%
Beta Advantage® Multi-Sector Municipal Bond Index (reflects no deductions for fees, expenses or taxes)		-8.46%	2.21%
Bloomberg Municipal Bond Index (reflects no deductions for fees, expenses or taxes)		-8.53%	1.74%

Portfolio Management		Title		Role with Fund		Managed Fund Since
Catherine Stienstra		Senior Portfolio Manager and Head of Municipal Bond Investments		Lead Portfolio Manager		2018
Douglas Rangel, CFA		Senior Portfolio Manager		Portfolio Manager		June 2022
William (Bill) L. Callagy		Portfolio Manager		Portfolio Manager		June 2022

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 50,000 shares, called Creation Units. Creation Units are issued and redeemed typically for an in-kind basket of securities. 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.

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Investment Objective

The Index, and therefore the Fund, will have exposure to the following five segments of the municipal debt market (% amount noted is the Index’s allocation to the particular segment at Index rebalancing and reconstitution, as described below): the Municipal Core Revenue Segment, as described below (45%); health care-related debt – the Municipal Health Care Segment (20%); high quality revenue bonds – the Municipal High Quality Revenue Segment (15%); general obligation (GO) bonds – the Municipal Core GO Segment (10%); and high yield debt (also known as “junk bonds”) – the Municipal High Yield Segment (10%). Each of the five Segment’s component bonds, other than the Municipal High Yield Segment, is derived from a sub-set index or indices of the Bloomberg Barclays Municipal Bond Index (the Parent Index), which serves as each segment’s starting universe of securities eligible for inclusion in the Index. The Parent Index is a broad-based, market value-weighted index designed to measure the performance of the U.S. municipal bond market. The Index is designed to achieve higher yields and stronger risk-adjusted returns relative to that of the Parent Index. The Index’s allocation to each of the five segments of the municipal debt market, represented by five sub-index models is fixed as of each Index rebalancing and reconstitution, but may vary due to the performance of each segment between these events. The number of securities in each of the five sub-index models and the Index as a whole noted below are as of January 31, 2023 and may change over time. The five sub-index models, each as discussed below, will generate all of the component securities of the Index. Each sub-index model, as well as the Index itself, is market-value weighted.

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for the Bloomberg Barclays Municipal Bond: Electric Index and the Bloomberg Barclays Municipal Bond: Education Index, and $30 million for the Bloomberg Barclays Municipal Bond: Transportation Index; and were issued as part of a transaction of at least $100 million. At January 31, 2023, this sub-index model held 1,598 securities.

Beta Advantage^® Strategy to Investing in the Municipal Health Care Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those securities included in the Bloomberg Barclays Municipal Bond: Hospital Index that meet the following criteria: are rated Aa2 or lower; have a remaining maturity of between and including 10 and 25 years; have an outstanding par value of at least $10 million; and were issued as part of a transaction of at least $100 million. At January 31, 2023, this sub-index model held 1,476 securities.

Beta Advantage^® Strategy to Investing in the Municipal High Quality Revenue Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those securities included in the: (i) Bloomberg Barclays Municipal Bond: Housing Index that meet the following criteria: are rated Aa2 or higher; have a remaining maturity of between and including 2 and 15 years; have an outstanding par value of at least $10 million; and were issued as part of a transaction of at least $100 million; and (ii) the Bloomberg Barclays Municipal Bond: Water & Sewer Index that meet the following criteria: are rated A2 or higher; have a remaining maturity of between and including 2 and 10 years; have an outstanding par value of at least $15 million; and were issued as part of a transaction of at least $100 million. At January 31, 2023, this sub-index model held 825 securities.

Beta Advantage^® Strategy to Investing in the Municipal Core GO Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those securities included in the Bloomberg Barclays Municipal Bond: GO Index that meet the following criteria: are rated Aa3 or higher; have a remaining maturity of between and including 2 and 10 years; have an outstanding par value of at least $15 million for local GO bonds and $25 million for state GO bonds; and were issued as part of a transaction of at least $100 million. At January 31, 2023, this sub-index model held 1,752 securities.

Beta Advantage^® Strategy to Investing in the Municipal High Yield Segment. As part of its multi-sector approach, the Index holds, and therefore the Fund invests in, those securities included in the Bloomberg Barclays Municipal High Yield Bond Index that meet the following criteria: are rated B3 or higher; have a remaining maturity of between and including 10 and 25 years; have an outstanding par value of at least $5 million; and were issued as part of a transaction of at least $25 million. Tobacco bonds are excluded from this sector. At January 31, 2023, this sub-index model held 476 securities.

As noted above, the five sub-index models will generate all of the component securities of the Index. Columbia Management expects to utilize a “representative sampling” strategy whereby the Fund invests in only some of the component securities of the Index that, collectively, are believed by the Investment Manager to generally reflect the same risk and return characteristics of the Index. As such, the Fund may not track the Index with the same degree of accuracy as would a fund replicating (or investing in) the entire Index. Through its representative sampling investment technique, the Fund expects to typically hold 650-750 holdings, which is a subset of the total number of holdings in the Index, which, as of January 31, 2023, had 6,127 holdings. There may be instances in which the Fund may overweight (or underweight) an Index holding, purchase (or sell) instruments not in the Index as a substitute for one or more securities in the Index or utilize various combinations of other available investment techniques in seeking to track the performance of the Index. The Fund may hold less than or more than the typical number of holdings in the range stated above, with the Fund portfolio management team applying investment experience and insight with the goal of seeking investment results that closely correspond to the performance of the Index.

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An investment in the Fund involves risks, including Interest Rate Risk, Credit Risk, Market Risk, Municipal Securities Risk, Passive Investment Risk, and Correlation/Tracking Error 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.

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 is heightened in times of market stress, including at both the Fund share level and at the Fund holdings level.

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investment vehicle replicating the entire Index. In addition, the Fund may invest in securities or other instruments not included in the Index. The Fund may take or refrain from taking investment positions for various reasons, such as tax efficiency purposes, or to comply with regulatory restrictions, which may negatively affect the Fund’s correlation with the Index. The Fund may also be subject to large movements of assets into and out of the Fund, potentially resulting in the Fund being over- or under-exposed to certain components of the Index and may be impacted by Index reconstitutions and Index rebalancing events. Holding cash balances may detract from the Fund’s ability to track the Index. In addition, the Fund’s NAV may deviate from the Index if the Fund fair values a portfolio security at a price other than the price used by the Index for that security. The Fund also bears management and other expenses and transaction costs in trading securities or other instruments, which the Index does not bear. The Fund, unlike the Index, is subject to regulatory requirements that can limit the Fund’s investments relative to what the Index can hold. The Fund, unlike the Index, is subject to Office of Foreign Assets Control and other regulatory restrictions, including, for example, restrictions on the ability of the Fund to invest in or hold certain securities. If the Fund is restricted from investing in or holding a security that was a component of the Index, and the Index did not remove such security, timely or at all, the Fund’s ability to track the Index could be negatively impacted. Accordingly, the Fund’s performance will likely fail to match the performance of the Index, after taking expenses into account, as well as regulatory limitations. Any of these factors could decrease correlation between the performance of the Fund and the Index and may hinder the Fund’s ability to meet its investment objective. It is not possible to invest directly in an index.

Credit Risk. Credit risk is the risk that the value of debt instruments may decline if the issuer thereof defaults or otherwise becomes unable or unwilling, or is perceived to be unable or unwilling, to honor its financial obligations, such as making payments to the Fund when due. Various factors could affect the actual or perceived willingness or ability of the issuer to make timely interest or principal payments, including changes in the financial condition of the issuer or in general economic conditions. Debt instruments backed by an issuer's taxing authority may be subject to legal limits on the issuer's power to increase taxes or otherwise to raise revenue, or may be dependent on legislative appropriation or government aid. Certain debt instruments are backed only by revenues derived from a particular project or source, rather than by an issuer's taxing authority, and thus may have a greater risk of default. Credit rating agencies, such as S&P Global Ratings, Moody’s, Fitch, DBRS and KBRA, assign credit ratings to certain debt instruments to indicate their credit risk. A rating downgrade by such agencies can negatively impact the value of such instruments. Lower-rated or unrated instruments held by the Fund may present increased credit risk as compared to higher-rated instruments. Non-investment grade debt instruments may be subject to greater price fluctuations and are more likely to experience a default than investment grade debt instruments and therefore may expose the Fund to increased credit risk.

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. In these circumstances, the Fund may be unable to rebalance and reconstitute its portfolio, may be unable to accurately price its investments, may incur substantial trading losses and/or may be prevented from sufficiently tracking the performance of the Index.

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

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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.

Index Methodology and Provider Risk. The Fund seeks performance that corresponds to the performance of the Index. There is no guarantee or assurance that the Index will achieve high, or even positive, returns. The Index may underperform more traditional indices. In turn, the Fund could lose value while other indices or measures of market performance increase in value or performance. In addition, the Fund may be subject to the risk that the Index Provider may not follow its stated methodology for construction or errors may be made in Index computation, construction and reconstitution, as applicable, despite any Index Provider procedures designed to prevent such occurrences and due diligence conducted by the Investment Manager. Errors may result in a negative performance impact to the Fund and its shareholders. The decision of whether to remove a security from the tracking index is made by an independent index provider who is not affiliated with the Fund or the Investment Manager.

Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if interest rates rise, the values of debt instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund receives from it but will generally affect the value of your investment in the Fund. Changes in interest rates may also affect the liquidity of the Fund’s investments in debt instruments. In general, the longer the maturity or duration of a debt instrument, the greater its sensitivity to changes in interest rates. Interest rate declines also may increase prepayments of debt obligations, which, in turn, would increase prepayment risk (the risk that the Fund will have to reinvest the money received in securities that have lower yields). Very low or negative interest rates may impact the Fund’s yield and may increase the risk that, if followed by rising interest rates, the Fund’s performance will be negatively impacted. The Fund is subject to the risk that the income generated by its investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates. Higher periods of inflation could lead such authorities to raise interest rates. Such actions may negatively affect the value of debt instruments held by the Fund, resulting in a negative impact on the Fund's performance and NAV. Any interest rate increases could cause the value of the Fund’s investments in debt instruments to decrease. Rising interest rates may prompt redemptions from the Fund, which may force the Fund to sell investments at a time when it is not advantageous to do so, which could result in losses.

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including banks and broker-dealers, willing to make markets (match up sellers and buyers) in the Fund’s investments or decreases in their capacity or willingness to trade such investments may increase the Fund’s exposure to this risk. The debt market has experienced considerable growth, and financial institutions making markets in instruments purchased and sold by the Fund (e.g., bond dealers) have been subject to increased regulation. The impact of that growth and regulation on the ability and willingness of financial institutions to engage in trading or “making a market” in such instruments remains unsettled. Certain types of investments, such as lower-rated securities or those that are purchased and sold in over-the-counter markets, may be especially subject to liquidity risk. Securities or other assets in which the Fund invests may be traded in the over-the-counter market rather than on an exchange and therefore may be more difficult to purchase or sell at a fair price, which may have a negative impact on the Fund’s performance. Market participants attempting to sell the same or a similar instrument at the same time as the Fund could exacerbate the Fund’s exposure to liquidity risk. The Fund may have to accept a lower selling price for the holding, sell other liquid or more liquid investments that it might otherwise prefer to hold (thereby increasing the proportion of the Fund’s investments in less liquid or illiquid securities), or forego another more appealing investment opportunity. The liquidity of Fund investments may change significantly over time and certain investments that were liquid when purchased by the Fund may later become illiquid, particularly in times of overall economic distress. Changing regulatory, market or other conditions or environments (for example, the interest rate or credit environments) may also adversely affect the liquidity and the price of the Fund's investments. Judgment plays a larger role in valuing illiquid or less liquid investments as compared to valuing liquid or more liquid investments. Price volatility may be higher for illiquid or less liquid investments as a result of, for example, the relatively less frequent pricing of such securities (as compared to liquid or more liquid investments). Generally, the less liquid the market at the time the Fund sells a portfolio investment, the greater the risk of loss or decline of value to the Fund. Overall market liquidity and other factors can lead to an increase in redemptions of creation units, which may negatively impact Fund performance and NAV, including, for example, if the Fund is forced to sell investments in a down market. In certain circumstances, the Fund might not be able to dispose of certain holdings quickly or at fair prices, preventing the Fund from tracking the Index. The municipal securities market is an over-the-counter market, which means that the Fund purchases and sells investments through municipal bond dealers. The Fund’s ability to sell investments held in its portfolio is dependent on the willingness and ability of market participants to provide bids that, in the view of portfolio management, reflect current market prices. Adverse market conditions could result in a lack of liquidity by reducing the number of ready buyers. In addition, in stressed market conditions, the market for Fund shares may become less liquid. Deterioration in the liquidity of Fund shares may adversely impact the liquidity of the Fund's underlying portfolio securities. These adverse impacts on the liquidity of Fund shares and on the liquidity of the Fund's underlying portfolio securities could in turn lead to 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.

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. 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.

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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/or wider bid/ask spreads than those experienced by other ETFs.

Money Market Fund Investment Risk. An investment in a money market fund is not a bank deposit and is not insured or guaranteed by any bank, the FDIC or any other government agency. Certain money market funds float their NAV while others seek to preserve the value of investments at a stable NAV (typically $1.00 per share). An investment in a money market fund, even an investment in a fund seeking to maintain a stable NAV per share, is not guaranteed and it is possible for the Fund to lose money by investing in these and other types of money market funds. If the liquidity of a money market fund’s portfolio deteriorates below certain levels, the money market fund may suspend redemptions (i.e., impose a redemption gate) and thereby prevent the Fund from selling its investment in the money market fund or impose a fee of up to 2% on amounts the Fund redeems from the money market fund (i.e., impose a liquidity fee). These measures may result in an investment loss or prohibit the Fund from redeeming shares when the Investment Manager would otherwise redeem shares. In addition to the fees and expenses that the Fund directly bears, the Fund indirectly bears the fees and expenses of any money market funds in which it invests, including affiliated money market funds. To the extent these fees and expenses, along with the fees and expenses of any other funds in which the Fund may invest, are expected to equal or exceed 0.01% of the Fund’s average daily net assets, they will be reflected in the Annual Fund Operating Expenses set forth in the table under “Fees and Expenses of the Fund.” By investing in a money market fund, the Fund will be exposed to the investment risks of the money market fund in direct proportion to such investment. The money market fund may not achieve its investment objective. The Fund, through its investment in the money market fund, may not achieve its investment objective. To the extent the Fund invests in instruments such as derivatives, the Fund may hold investments, which may be significant, in money market fund shares to cover its obligations resulting from the Fund’s investments in such instruments. Money market funds and the securities they invest in are subject to comprehensive regulations. The enactment of new legislation or regulations, as well as changes in interpretation and enforcement of current laws, may affect the manner of operation, performance and/or yield of money market funds.

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Passive Investment Risk. The Fund is not actively managed and may be affected by a general decline in market segments related to its Index’s investment exposures. The Fund invests in securities or instruments included in, or believed by the Investment Manager to be representative of the Index regardless of their investment merits. The Fund does not seek temporary defensive positions when markets decline or appear overvalued.

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 shares. In addition, secondary market investors will also incur the cost of the difference between the price that an investor is willing to pay for Fund shares (the bid price) and the price at which an investor is willing to sell Fund shares (the ask price). This difference in bid and ask prices is often referred to as the “spread” or “bid/ask spread.” The bid/ask spread varies over time for Fund shares based on trading volume and market liquidity, and is generally lower if the Fund’s shares have more trading volume and market liquidity and higher if the Fund’s shares have little trading volume and market liquidity. Further, increased market volatility may cause widening of bid/ask spreads.

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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 typically for an in-kind basket of securities. 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 50,000 shares (which is the case for the Fund), called Creation Units.

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The Fund may enter into derivative transactions. Derivatives are financial contracts whose values are, for example, based on (or “derived” from) traditional securities (such as a stock or bond), assets (such as a commodity like gold or a foreign currency), reference rates (such as the Secured Overnight Financing Rate (commonly known as SOFR) or the London Interbank Offered Rate (commonly known as LIBOR)) or market indices (such as the Standard & Poor’s 500® Index). The use of derivatives is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. Derivatives involve special risks and may result in losses or may limit the Fund’s potential gain from favorable market movements. Derivative strategies often involve leverage, which may exaggerate a loss, potentially causing the Fund to lose more money than it would have lost had it invested in the underlying security or other asset directly. The values of derivatives may move in unexpected ways, especially in unusual market conditions, and may result in increased volatility in the value of the derivative and/or the Fund’s shares, among other consequences.  The use of derivatives may also increase the amount of taxes payable by shareholders holding shares in a taxable account. Other risks arise from the Fund’s potential inability to terminate or to sell derivative positions. A liquid secondary market may not always exist for the

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Fund’s derivative positions at times when the Fund might wish to terminate or to sell such positions. Over-the-counter instruments (investments not traded on an exchange) may be illiquid, and transactions in derivatives traded in the over-the-counter market are subject to the risk that the other party will not meet its obligations. The use of derivatives also involves the risks of mispricing or improper valuation and that changes in the value of the derivative may not correlate perfectly with the underlying security, asset, reference rate or index. The Fund also may not be able to find a suitable derivative transaction counterparty, and thus may be unable to engage in derivative transactions when it is deemed favorable to do so, or at all. U.S. federal legislation has been enacted that provides for new clearing, margin, reporting and registration requirements for participants in the derivatives market. These changes could restrict and/or impose significant costs or other burdens upon the Fund’s participation in derivatives transactions. The U.S. government and the European Union (and some other jurisdictions) have enacted regulations and similar requirements that prescribe clearing, margin, reporting and registration requirements for participants in the derivatives market. These requirements are evolving and their ultimate impact on the Fund remains unclear, but such impact could include restricting and/or imposing significant costs or other burdens upon the Fund’s participation in derivatives transactions. Additionally, in October 2020, the SEC adopted new regulations governing the use of derivatives by registered investment companies. Rule 18f-4, among other things, requires a fund that invests in derivative instruments beyond a specified limited amount to apply a value-at-risk-based limit to its portfolio and establish a comprehensive derivatives risk management program. As of the date of this prospectus, the Fund is not required to maintain a comprehensive derivatives risk management program under Rule 18f-4 given its more limited use of derivatives. For more information on the risks of derivative investments and strategies, see the SAI.

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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 Management		Title		Role with Fund		Managed Fund Since
Catherine Stienstra		Senior Portfolio Manager and Head of Municipal Bond Investments		Lead Portfolio Manager		2018
Douglas Rangel, CFA		Senior Portfolio Manager		Portfolio Manager		June 2022
William (Bill) L. Callagy		Portfolio Manager		Portfolio Manager		June 2022

Mr. Rangel joined the Investment Manager in 2019. Prior to joining the Investment Manager, he was a senior director for client portfolio management at Galliard Capital Management, a wholly-owned subsidiary of Wells Fargo. Mr. Rangel began his investment career in 2000 and earned a B.A. in Business Management from Greenville University and an M.B.A. from the University of St. Thomas.

Mr. Callagy joined the Investment Manager in 2017. Mr. Callagy began his investment career in 2008 and earned a B.S. from Fairfield University.

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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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Shares are issued or redeemed by the Fund at NAV per share only in Creation Units of 50,000 shares. As of December 31, 2022, the value of one Creation Unit of the Fund was $1,006,864.08.

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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.

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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.

NAV Calculation

The Fund calculates its NAV as follows:

NAV =  (Value of assets) – (Liabilities)
Number of outstanding shares

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

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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 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 to Shareholders

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:

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 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. The Fund expects to distribute net capital gains (if any) resulting from the Fund’s portfolio re-balancing, maturities, and other taxable dispositions of securities.

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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.

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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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Information regarding how often the shares of the Fund traded on the Exchange at a price above (at a premium) or below (at a discount) the NAV of the Fund during the past four calendar quarters can be found at the Internet address noted below.

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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	2021	2020	2019	2018(a)
Per share data
Net asset value, beginning of year	$22.30	$21.83	$21.56	$20.02	$20.00
Income (loss) from investment operations:
Net investment income	0.34	0.37	0.51	0.56	0.03
Net realized and unrealized gain (loss)	(3.03)	0.52	0.30	1.51	(0.01)
Total from investment operations	(2.69)	0.89	0.81	2.07	0.02
Less distributions to shareholders:
Net investment income	(0.32)	(0.38)	(0.51)	(0.53)	–
Net realized gains	(0.02)	(0.04)	(0.03)	–	–
Total distribution to shareholders	(0.34)	(0.42)	(0.54)	(0.53)	–
Net asset value, end of year	$19.27	$22.30	$21.83	$21.56	$20.02
Total Return at NAV	(12.17)%	4.11%	3.82%	10.42%	0.10%
Total Return at Market	(12.40)%	3.85%	4.18%	10.24%	0.45%
Ratios to average net assets:
Total gross expenses(b)	0.23%(c)	0.23%(c)	0.23%	0.26%	0.28%(d)
Total net expenses(b)(e)	0.23%(c)	0.23%(c)	0.23%	0.26%	0.28%(d)
Net investment income	1.63%	1.65%	2.37%	2.67%	2.34%(d)
Supplemental data
Net assets, end of year (in thousands)	$223,585	$141,619	$56,769	$26,946	$16,014
Portfolio turnover	14%	6%	11%	20%	48%

(c)	The ratio includes less than 0.01% attributed to overdraft expense, which is outside the Unitary Fee (as defined in Note 3).

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By Telephone: 800.426.3750

© 2023 Columbia Management Investment Advisers, LLC. All rights reserved.

PRO303_10_N01_(03/23)

Beta Advantage^® ETFs

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Mid-Cap Stock Risk. Investments in mid-capitalization companies (mid-cap companies) often involve greater risks than investments in larger, more established companies (larger companies) because 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, and may be less liquid than the securities of larger companies.

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Information Technology Sector. The Fund is more susceptible to the particular risks that may affect companies in the information technology sector than if it were invested in a wider variety of companies in unrelated sectors. Companies in the information technology sector are subject to certain risks, including the risk that new services, equipment or technologies will not be accepted by consumers and businesses or will become rapidly obsolete. Performance of such companies may be affected by factors including obtaining and protecting patents (or the failure to do so) and significant competitive pressures, including aggressive pricing of their products or services, new market entrants, competition for market share and short product cycles due to an accelerated rate of technological developments. Such competitive pressures may lead to limited earnings and/or falling profit margins. As a result, the value of their securities may fall or fail to rise. In addition, many information technology sector companies have limited operating histories and prices of these companies’ securities historically have been more volatile than other securities, especially over the short term. Some companies in the information technology sector are facing increased government and regulatory scrutiny and may be subject to adverse government or regulatory action, which could negatively impact the value of their securities.

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Year by Year Total Return (%) as of December 31 Each Year	Best and Worst Quarterly Returns During the Period Shown in the Bar Chart
	Best	2nd Quarter 2020	20.64%
	Worst	1st Quarter 2020	-20.42%

	Inception Date	1 Year	Life of Fund
At NAV	09/25/2019
returns before taxes		-14.30%	11.73%
returns after taxes on distributions		-14.60%	9.12%
returns after taxes on distributions and sale of Fund shares		-8.28%	8.36%
Beta Advantage® Research Enhanced U.S. Equity Index (reflects no deductions for fees, expenses or taxes)		-14.21%	11.95%
Russell 1000® Index (reflects no deductions for fees, expenses or taxes)		-19.13%	9.69%

Portfolio Management		Title		Role with Fund		Managed Fund Since
Christopher Lo, CFA		Senior Portfolio Manager		Lead Portfolio Manager		2019
Jason Wang, CFA		Portfolio Manager		Portfolio Manager		2019

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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 typically for an in-kind basket of securities. 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.

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Mid-Cap Stock Risk. Investments in mid-capitalization companies (mid-cap companies) often involve greater risks than investments in larger, more established companies (larger companies) because 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, and may be less liquid than the securities of larger companies.

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Financial Services Sector. The Fund is more susceptible to the particular risks that may affect companies in the financial services sector than if it were invested in a wider variety of companies in unrelated sectors. Companies in the financial services sector are subject to certain risks, including the risk of regulatory change, decreased liquidity in credit markets and unstable interest rates. Such companies may have concentrated portfolios, such as a high level of loans to one or more industries or sectors, which makes them vulnerable to economic conditions that affect such industries or sectors. Performance of such companies may be affected by competitive pressures and exposure to investments, agreements and counterparties, including credit products that, under certain circumstances, may lead to losses (e.g., subprime loans). Companies in the financial services sector are subject to extensive governmental regulation that may limit the amount and types of loans and other financial commitments they can make, and the interest rates and fees they may charge. In addition, profitability of such companies is largely dependent upon the availability and the cost of capital.

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Year by Year Total Return (%) as of December 31 Each Year	Best and Worst Quarterly Returns During the Period Shown in the Bar Chart
	Best	4th Quarter 2020	15.13%
	Worst	1st Quarter 2020	-26.26%

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	Inception Date	1 Year	Life of Fund
At NAV	09/25/2019
returns before taxes		-5.82%	8.94%
returns after taxes on distributions		-6.36%	6.68%
returns after taxes on distributions and sale of Fund shares		-3.07%	6.55%
Beta Advantage® Research Enhanced U.S. Value Index (reflects no deductions for fees, expenses or taxes)		-5.66%	9.07%
Russell 1000® Value Index (reflects no deductions for fees, expenses or taxes)		-7.54%	7.89%

Portfolio Management		Title		Role with Fund		Managed Fund Since
Christopher Lo, CFA		Senior Portfolio Manager		Lead Portfolio Manager		2019
Jason Wang, CFA		Portfolio Manager		Portfolio Manager		2019

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 typically for an in-kind basket of securities. 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.

16	Prospectus 2023

Investment Objective

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17

The methodology applied to select Index holdings and weightings does not set limits on sector or industry exposures. To the extent the Index is concentrated in a sector or industry, the Fund will necessarily be concentrated in that sector or industry. As of October 31, 2022, the Index (and therefore the Fund) was concentrated in the information technology sector.

An investment in the Fund involves risks, including Passive Investment Risk, Market Risk, and Correlation/Tracking Error 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.

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 is heightened in times of market stress, including at both the Fund share level and at the Fund holdings level.

18	Prospectus 2023

proportion as their weighting in the Index, at times, the Fund may not have investment exposure to all components of the Index, or its weighting of investment exposure to such components may be different from that of the Index. In addition, the Fund may invest in securities or other instruments not included in the Index. The Fund may take or refrain from taking investment positions for various reasons, such as tax efficiency purposes, or to comply with regulatory restrictions, which may negatively affect the Fund’s correlation with the Index. The Fund may also be subject to large movements of assets into and out of the Fund, potentially resulting in the Fund being over- or under-exposed to certain components of the Index and may be impacted by Index reconstitutions and Index rebalancing events. Additionally, the Fund's foreign investments may trade on markets that may not be open on the same day or at the same time as the Fund, which may cause a difference between the changes in the daily performance of the Fund and changes in the level of the Index. Furthermore, the Fund may need to execute currency trades that due to regulatory, legal and operational constraints will occur at a later date than the trading of the related security. Currency holdings may be valued at a different time and at different rates than that used by the Index. Holding cash balances may detract from the Fund’s ability to track the Index. In addition, the Fund’s NAV may deviate from the Index if the Fund fair values a portfolio security at a price other than the price used by the Index for that security. The Fund also bears management and other expenses and transaction costs in trading securities or other instruments, which the Index does not bear. The Fund, unlike the Index, is subject to regulatory requirements that can limit the Fund’s investments relative to what the Index can hold. The Fund, unlike the Index, is subject to Office of Foreign Assets Control and other regulatory restrictions, including, for example, restrictions on the ability of the Fund to invest in or hold certain securities. If the Fund is restricted from investing in or holding a security that was a component of the Index, and the Index did not remove such security, timely or at all, the Fund’s ability to track the Index could be negatively impacted. Accordingly, the Fund’s performance will likely fail to match the performance of the Index, after taking expenses into account, as well as regulatory limitations. Any of these factors could decrease correlation between the performance of the Fund and the Index and may hinder the Fund’s ability to meet its investment objective. It is not possible to invest directly in an index.

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. In these circumstances, the Fund may be unable to rebalance and reconstitute its portfolio, may be unable to accurately price its investments, may incur substantial trading losses and/or may be prevented from sufficiently tracking the performance of the Index.

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.

Index Methodology and Provider Risk. The Fund seeks performance that corresponds to the performance of the Index. There is no guarantee or assurance that the Index will achieve high, or even positive, returns. The Index may underperform more traditional indices. In turn, the Fund could lose value while other indices or measures of market performance increase in value or performance. In addition, the Fund may be subject to the risk that the Index

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Provider may not follow its stated methodology for construction or errors may be made in Index computation, construction, reconstitution and rebalancing, despite any Index Provider procedures designed to prevent such occurrences and due diligence conducted by the Investment Manager. Errors may result in a negative performance impact to the Fund and its shareholders. The Fund tracks an index that is owned and/or was developed by the Investment Manager.

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/or wider bid/ask spreads than those experienced by other ETFs.

■

Mid-Cap Stock Risk. Securities of mid-cap companies can, in certain circumstances, have more risk than securities of larger companies. For example, 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. 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 mid-cap companies may trade less frequently and in smaller volumes and may fluctuate more sharply in value than securities of larger companies. When the Fund takes significant positions in mid-cap companies with limited trading volumes, the liquidation of those positions, particularly in a distressed market, could be difficult and result in Fund investment losses that would affect the value of your investment in the Fund. In addition, some mid-cap companies may not be widely followed by the investment community, which can lower the demand for their stocks.

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. 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

20	Prospectus 2023

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/or 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.

Passive Investment Risk. The Fund is not actively managed and may be affected by a general decline in market segments related to its Index’s investment exposures. The Fund invests in securities or instruments included in, or believed by the Investment Manager to be representative of the Index regardless of their investment merits. The Fund does not seek temporary defensive positions when markets decline or appear overvalued.

Quantitative Models Risk. Quantitative models used by the Index may not be effective in selecting the most favorable securities for inclusion in the Index and may cause the Fund to underperform other investment strategies for short or long periods of time. Performance will depend upon the quality and accuracy of the assumptions, theories and framework upon which a quantitative model is based. The success of a quantitative model will depend upon its accurate reflection of market conditions, with proper adjustments as market conditions change over time. Adjustments, or lack of adjustments, to the quantitative model, including as conditions change, as well as any errors or imperfections in the quantitative model, could adversely affect Fund performance. The performance of a quantitative model depends upon the quality of its design and effective execution under actual market conditions. Even a well-designed quantitative model cannot be expected to perform well in all market conditions or across all time intervals. Quantitative models may underperform in certain market environments including stressed or volatile

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21

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 shares. In addition, secondary market investors will also incur the cost of the difference between the price that an investor is willing to pay for Fund shares (the bid price) and the price at which an investor is willing to sell Fund shares (the ask price). This difference in bid and ask prices is often referred to as the “spread” or “bid/ask spread.” The bid/ask spread varies over time for Fund shares based on trading volume and market liquidity, and is generally lower if the Fund’s shares have more trading volume and market liquidity and higher if the Fund’s shares have little trading volume and market liquidity. Further, increased market volatility may cause widening of bid/ask spreads.

Sector Risk. At times, the Fund may have a significant portion of its assets invested in securities of companies conducting business in a related group of industries within one or more economic sectors, including the information technology sector. The Fund will concentrate its investments in issuers conducting business in a related group of industries to approximately the same extent as the Index. Companies in the same sector may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund more vulnerable to unfavorable developments in that group of industries or economic sector than funds that invest more broadly. Generally, the more broadly the Fund invests, the more it spreads risk and potentially reduces the risks of loss and volatility.

■

Information Technology Sector. The Fund is more susceptible to the particular risks that may affect companies in the information technology sector than if it were invested in a wider variety of companies in unrelated sectors. Companies in the information technology sector are subject to certain risks, including the risk that new services, equipment or technologies will not be accepted by consumers and businesses or will become rapidly obsolete. Performance of such companies may be affected by factors including obtaining and protecting patents (or the failure to do so) and significant competitive pressures, including aggressive pricing of their products or services, new market entrants, competition for market share and short product cycles due to an accelerated rate of technological developments. Such competitive pressures may lead to limited earnings and/or falling profit margins. As a result, the value of their securities may fall or fail to rise. In addition, many information technology sector companies have limited operating histories and prices of these companies’ securities historically have been more volatile than other securities, especially over the short term. Some companies in the information technology sector are facing increased government and regulatory scrutiny and may be subject to adverse government or regulatory action, which could negatively impact the value of their securities.

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Investment Objective

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The methodology applied to select Index holdings and weightings does not set limits on sector or industry exposures. To the extent the Index is concentrated in a sector or industry, the Fund will necessarily be concentrated in that sector or industry. As of October 31, 2022, the Index (and therefore the Fund) was concentrated in the financial services sector.

An investment in the Fund involves risks, including Value Securities Risk, Passive Investment Risk, Market Risk,  and Correlation/Tracking Error 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.

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 is heightened in times of market stress, including at both the Fund share level and at the Fund holdings level.

24	Prospectus 2023

or other instruments in which the Fund invests. While the Fund typically seeks to track the performance of the Index by investing all, or substantially all, of its assets in the components of the Index in approximately the same proportion as their weighting in the Index, at times, the Fund may not have investment exposure to all components of the Index, or its weighting of investment exposure to such components may be different from that of the Index. In addition, the Fund may invest in securities or other instruments not included in the Index. The Fund may take or refrain from taking investment positions for various reasons, such as tax efficiency purposes, or to comply with regulatory restrictions, which may negatively affect the Fund’s correlation with the Index. The Fund may also be subject to large movements of assets into and out of the Fund, potentially resulting in the Fund being over- or under-exposed to certain components of the Index and may be impacted by Index reconstitutions and Index rebalancing events. Additionally, the Fund's foreign investments may trade on markets that may not be open on the same day or at the same time as the Fund, which may cause a difference between the changes in the daily performance of the Fund and changes in the level of the Index. Furthermore, the Fund may need to execute currency trades that due to regulatory, legal and operational constraints will occur at a later date than the trading of the related security. Currency holdings may be valued at a different time and at different rates than that used by the Index. Holding cash balances may detract from the Fund’s ability to track the Index. In addition, the Fund’s NAV may deviate from the Index if the Fund fair values a portfolio security at a price other than the price used by the Index for that security. The Fund also bears management and other expenses and transaction costs in trading securities or other instruments, which the Index does not bear. The Fund, unlike the Index, is subject to regulatory requirements that can limit the Fund’s investments relative to what the Index can hold. The Fund, unlike the Index, is subject to Office of Foreign Assets Control and other regulatory restrictions, including, for example, restrictions on the ability of the Fund to invest in or hold certain securities. If the Fund is restricted from investing in or holding a security that was a component of the Index, and the Index did not remove such security, timely or at all, the Fund’s ability to track the Index could be negatively impacted. Accordingly, the Fund’s performance will likely fail to match the performance of the Index, after taking expenses into account, as well as regulatory limitations. Any of these factors could decrease correlation between the performance of the Fund and the Index and may hinder the Fund’s ability to meet its investment objective. It is not possible to invest directly in an index.

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. In these circumstances, the Fund may be unable to rebalance and reconstitute its portfolio, may be unable to accurately price its investments, may incur substantial trading losses and/or may be prevented from sufficiently tracking the performance of the Index.

Exchange-Traded Fund (ETF) Risk. Investments in ETFs have unique characteristics, including, but not limited to, the expense structure and additional expenses associated with investing in ETFs. An ETF’s share price may not track its specified market index (if any) and may trade below its NAV. Certain ETFs use a “passive” investment strategy and do not take defensive positions in volatile or declining markets. Other ETFs in which the Fund may invest are actively managed ETFs (i.e., they do not track a particular benchmark), which indirectly subjects the Fund to active management risk. An active secondary market in ETF shares may not develop or be maintained and may be halted or interrupted due to actions by its listing exchange, unusual market conditions or other reasons. There can be no assurance that an ETF’s shares will continue to be listed on an active exchange. In addition, the Fund’s shareholders bear both their proportionate share of the Fund’s expenses and, indirectly, the ETF’s expenses, incurred through the Fund’s ownership of the ETF. Because the expenses and costs of an underlying ETF are shared by its investors, redemptions by other investors in the ETF could result in decreased economies of scale and increased operating expenses for such ETF. These transactions might also result in higher brokerage, tax or other costs for the ETF. This risk may be particularly important when one investor owns a substantial portion of the ETF. There is a risk that ETFs in which the Fund invests may terminate due to extraordinary events. For example, any of the service providers to ETFs, such as the trustee or sponsor, may close or otherwise fail to perform their obligations to the ETF, and the ETF may not be able to find a substitute service provider. In addition, certain ETFs may be dependent upon licenses to use various indexes as a basis for determining their compositions and/or otherwise to use certain trade names. If these licenses are terminated, the ETFs may also terminate. An ETF may also terminate if its net assets fall below a certain amount.

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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.

Index Methodology and Provider Risk. The Fund seeks performance that corresponds to the performance of the Index. There is no guarantee or assurance that the Index will achieve high, or even positive, returns. The Index may underperform more traditional indices. In turn, the Fund could lose value while other indices or measures of market performance increase in value or performance. In addition, the Fund may be subject to the risk that the Index Provider may not follow its stated methodology for construction or errors may be made in Index computation, construction, reconstitution and rebalancing, despite any Index Provider procedures designed to prevent such occurrences and due diligence conducted by the Investment Manager. Errors may result in a negative performance impact to the Fund and its shareholders. The Fund tracks an index that is owned and/or was developed by the Investment Manager.

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/or wider bid/ask spreads than those experienced by other ETFs.

■

Mid-Cap Stock Risk. Securities of mid-cap companies can, in certain circumstances, have more risk than securities of larger companies. For example, 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. 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 mid-cap companies may trade less frequently and in smaller volumes and may fluctuate more sharply in value than securities of larger companies. When the Fund takes significant positions in mid-cap companies with limited trading volumes, the liquidation of those positions, particularly in a distressed market, could be difficult and result in Fund investment losses that would affect the value of your investment in the Fund. In addition, some mid-cap companies may not be widely followed by the investment community, which can lower the demand for their stocks.

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changes in NAV, as well as the relative supply of, and demand for, Fund shares on the Exchange. 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/or 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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Passive Investment Risk. The Fund is not actively managed and may be affected by a general decline in market segments related to its Index’s investment exposures. The Fund invests in securities or instruments included in, or believed by the Investment Manager to be representative of the Index regardless of their investment merits. The Fund does not seek temporary defensive positions when markets decline or appear overvalued.

Quantitative Models Risk. Quantitative models used by the Index may not be effective in selecting the most favorable securities for inclusion in the Index and may cause the Fund to underperform other investment strategies for short or long periods of time. Performance will depend upon the quality and accuracy of the assumptions, theories and framework upon which a quantitative model is based. The success of a quantitative model will depend upon its accurate reflection of market conditions, with proper adjustments as market conditions change over time. Adjustments, or lack of adjustments, to the quantitative model, including as conditions change, as well as any errors or imperfections in the quantitative model, could adversely affect Fund performance. The performance of a quantitative model depends upon the quality of its design and effective execution under actual market conditions. Even a well-designed quantitative model cannot be expected to perform well in all market conditions or across all time intervals. Quantitative models may underperform in certain market environments including stressed or volatile market conditions. It is not possible or practicable for a quantitative model to factor in all relevant, available data. There is no guarantee that the data actually utilized in a quantitative model will be the most accurate data available or be free from errors. There can be no assurance that the use of quantitative models will enable the Fund to achieve its objective.

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 shares. In addition, secondary market investors will also incur the cost of the difference between the price that an investor is willing to pay for Fund shares (the bid price) and the price at which an investor is willing to sell Fund shares (the ask price). This difference in bid and ask prices is often referred to as the “spread” or “bid/ask spread.” The bid/ask spread varies over time for Fund shares based on trading volume and market liquidity, and is generally lower if the Fund’s shares have more trading volume and market liquidity and higher if the Fund’s shares have little trading volume and market liquidity. Further, increased market volatility may cause widening of bid/ask spreads.

Sector Risk. At times, the Fund may have a significant portion of its assets invested in securities of companies conducting business in a related group of industries within one or more economic sectors, including the financial services sector. The Fund will concentrate its investments in issuers conducting business in a related group of industries to approximately the same extent as the Index. Companies in the same sector may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund more vulnerable to unfavorable developments in that group of industries or economic sector than funds that invest more broadly. Generally, the more broadly the Fund invests, the more it spreads risk and potentially reduces the risks of loss and volatility.

■

Financial Services Sector. The Fund is more susceptible to the particular risks that may affect companies in the financial services sector than if it were invested in a wider variety of companies in unrelated sectors. Companies in the financial services sector are subject to certain risks, including the risk of regulatory change, decreased liquidity in credit markets and unstable interest rates. Such companies may have concentrated portfolios, such as a high level of loans to one or more industries or sectors, which makes them vulnerable to economic conditions that affect such industries or sectors. Performance of such companies may be affected by competitive pressures and exposure to investments, agreements and counterparties, including credit products that, under certain circumstances, may lead to losses (e.g., subprime loans). Companies in the financial services sector are subject to extensive governmental regulation that may limit the amount and types of loans and other financial commitments they can make, and the interest rates and fees they may charge. In addition, profitability of such companies is largely dependent upon the availability and the cost of capital.

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References to “the Fund” throughout the remainder of the prospectus refer to the Funds singularly or collectively as the context requires.

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 typically for an in-kind basket of securities. 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.

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The Fund may enter into derivative transactions. Derivatives are financial contracts whose values are, for example, based on (or “derived” from) traditional securities (such as a stock or bond), assets (such as a commodity like gold or a foreign currency), reference rates (such as the Secured Overnight Financing Rate (commonly known as SOFR) or the London Interbank Offered Rate (commonly known as LIBOR)) or market indices (such as the Standard & Poor’s 500® Index). The use of derivatives is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. Derivatives involve special risks and may result in losses or may limit the Fund’s potential gain from favorable market movements. Derivative strategies often involve leverage, which may exaggerate a loss, potentially causing the Fund to lose more money than it would have lost had it invested in the underlying security or other asset directly. The values of derivatives may move in unexpected ways, especially in unusual market conditions, and may result in increased volatility in the value of the derivative and/or the Fund’s shares, among other consequences.  The use of derivatives may also increase the amount of taxes payable by shareholders holding shares in a taxable account. Other risks arise from the Fund’s potential inability to terminate or to sell derivative positions. A liquid secondary market may not always exist for the Fund’s derivative positions at times when the Fund might wish to terminate or to sell such positions. Over-the-counter instruments (investments not traded on an exchange) may be illiquid, and transactions in derivatives traded in the over-the-counter market are subject to the risk that the other party will not meet its obligations. The use of derivatives also involves the risks of mispricing or improper valuation and that changes in the value of the derivative may not correlate perfectly with the underlying security, asset, reference rate or index. The Fund also may not be able to find a suitable derivative transaction counterparty, and thus may be unable to engage in derivative transactions when it is deemed favorable to do so, or at all. U.S. federal legislation has been enacted that provides for new clearing, margin, reporting and registration requirements for participants in the derivatives market. These changes could restrict and/or impose significant costs or other burdens upon the Fund’s participation in derivatives transactions. The U.S. government and the European Union (and some other jurisdictions) have enacted regulations and similar

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requirements that prescribe clearing, margin, reporting and registration requirements for participants in the derivatives market. These requirements are evolving and their ultimate impact on the Fund remains unclear, but such impact could include restricting and/or imposing significant costs or other burdens upon the Fund’s participation in derivatives transactions. Additionally, in October 2020, the SEC adopted new regulations governing the use of derivatives by registered investment companies. Rule 18f-4, among other things, requires a fund that invests in derivative instruments beyond a specified limited amount to apply a value-at-risk-based limit to its portfolio and establish a comprehensive derivatives risk management program. As of the date of this prospectus, the Fund is not required to maintain a comprehensive derivatives risk management program under Rule 18f-4 given its more limited use of derivatives. For more information on the risks of derivative investments and strategies, see the SAI.

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	Investment advisory services fee rate for the fiscal year ended October 31, 2022
Columbia Research Enhanced Core ETF	0.15%
Columbia Research Enhanced Value ETF	0.19%

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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 Management		Title		Role with Fund		Managed Fund Since
Christopher Lo, CFA		Senior Portfolio Manager		Lead Portfolio Manager		2019
Jason Wang, CFA		Portfolio Manager		Portfolio Manager		2019

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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

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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 values of one Creation Unit were the following:

	Creation Unit Value
Columbia Research Enhanced Core ETF	$568,180.05
Columbia Research Enhanced Value ETF	$490,189.54

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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, principally in exchange for a basket of securities. 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.

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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.

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.

NAV Calculation

The Fund calculates its NAV as follows:

NAV =  (Value of assets) – (Liabilities)
Number of outstanding shares

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

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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 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 to Shareholders

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:

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 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.

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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.

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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Information regarding how often the shares of the Fund traded on the Exchange at a price above (at a premium) or below (at a discount) the NAV of the Fund during the past four calendar quarters can be found at the Internet address noted below.

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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	2021	2020	2019 (a)
Per share data
Net asset value, beginning of year	$31.23	$21.79	$20.31	$19.81
Income (loss) from investment operations:
Net investment income	0.39	0.41	0.37	0.04
Net realized and unrealized gain (loss)	(3.08)	9.30	1.22	0.46
Total from investment operations	(2.69)	9.71	1.59	0.50
Less distributions to shareholders:
Net investment income	(0.78)	(0.25)	(0.11)	–
Net realized gains	(4.78)	(0.02)	(0.00)(b)	–
Total distribution to shareholders	(5.56)	(0.27)	(0.11)	–
Net asset value, end of year	$22.98	$31.23	$21.79	$20.31
Total Return at NAV	(10.57)%	44.90%	7.82%	2.52%
Total Return at Market	(10.32)%	45.27%	7.46%	2.63%
Ratios to average net assets:
Total gross expenses(c)	0.15%	0.15%	0.15%	0.15%(d)
Total net expenses(c)(e)	0.15%	0.15%	0.15%	0.15%(d)
Net investment income	1.63%	1.58%	1.73%	1.77%(d)
Supplemental data
Net assets, end of year (in thousands)	$78,699	$28,107	$72,448	$5,079
Portfolio turnover	65%	49%	41%	0%