497K 1 acetftmusi497k.htm 497K Document

Summary Prospectus     

June 29, 2021
American Century® Multisector Income ETF
Ticker: MUSI
Exchange: NYSE Arca, Inc.
Before you invest, you may want to review the fund’s prospectus, which contains more information about the fund and its risks. You can find the fund’s prospectus, reports to shareholders, and other information about the fund online at americancentury.com/etfdocs. You can also get this information at no cost by calling 833-ACI-ETFS or sending an email request to prospectus@americancentury.com. The fund’s prospectus and other information are also available from financial intermediaries through which shares of the fund may be purchased or sold.

This summary prospectus incorporates by reference the fund’s prospectus and statement of additional information (SAI) each dated June 29, 2021 (as supplemented at the time you receive this summary prospectus). The fund’s SAI and annual report may be obtained, free of charge, in the same manner as the prospectus.

Investment Objective
The fund seeks to provide a high level of current income and total return.
Fees and Expenses
The following table describes the fees and expenses you may pay if you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fee0.35%
Other Expenses1
Total Annual Fund Operating Expenses0.35%
1 Other expenses are based on estimated amounts for the current fiscal year.
The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn a 5% return each year, and that the fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 year3 years
Portfolio Turnover
The fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. Because the fund is new, the fund’s portfolio turnover rate is not available.
Principal Investment Strategies
The fund invests in various sectors of the fixed income market holding instruments such as corporate bonds and notes, government securities, securitized credit instruments, and emerging markets debt securities. The portfolio managers select securities using a sector rotation approach that integrates proprietary fundamental research and quantitative model inputs, such as economic activity, inflation and monetary policy, and technical analysis of relative value among various sectors. The fund invests in both investment-grade and high-yield debt securities. Investment grade securities are those that have been rated in one of the top four credit quality categories by an independent rating agency or determined by the advisor to be of comparable credit quality. High-yield securities, which are also

known as “junk bonds,” are those that have been rated by an independent rating agency below the highest four categories or determined by the advisor to be of similar quality.
The debt securities in which the fund invests may be payable in U.S. or foreign currencies, including emerging markets currencies. The fund may also invest in certain equity securities such as preferred stock, convertible securities, or equity equivalents provided that such investments are consistent with the fund’s investment objectives. The fund has no average maturity or duration limitations.
In addition to the securities listed above, the fund may also invest in bank loans.
The fund may also utilize derivative instruments provided that such investments are in keeping with the fund’s investment objectives. Such derivative instruments include options, futures contracts, options on futures contracts, and swaps (such as credit default swaps either on a single issuer or a securities index), or in mortgage- or asset-backed securities. The fund may invest in collateralized debt obligations, including collateralized loan obligations, collateralized mortgage obligations, and other similarly structured investments. The fund may use foreign currency exchange contracts to shift investment exposure from one currency into another for hedging purposes or to enhance returns.
To determine whether to buy or sell a security, the portfolio managers consider the fund requirements and standards described above, along with economic conditions, alternative investments and interest rates.
The portfolio managers may engage in hedging of portfolio positions, which usually involves entering into a derivative transaction that has the opposite characteristic of the position being hedged. The net effect of these two positions is intended to reduce or eliminate the exposure created by the first position.
The fund is an actively managed exchange-traded fund (ETF) that does not seek to replicate the performance of a specified index. To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments, interest rates and various credit metrics.
Principal Risks
Interest Rate Risk - Investments in debt securities are also sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. The fund is more susceptible to interest rate changes than funds that have shorter-weighted average maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
Credit Risk - The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result, the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
High-Yield Risk - Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic down turn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer. These factors may be more likely to cause an issuer of low quality bonds to default on its obligations. Investment in high-yield securities is inherently speculative.
Foreign Securities Risk - Foreign securities have certain unique risks, such as currency risk, social, political and economic risk, and foreign market and trading risk. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
Emerging Market Risk – Investing in securities of companies located in emerging market countries generally is also riskier than investing in securities of companies located in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change. These changes may be magnified by the countries’ emergent financial markets, resulting in significant volatility to investments in these countries. These countries also may lack the legal, business and social framework to support securities markets.
Derivatives Risk - The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities. Derivatives are subject to a number of risks, including liquidity, interest rate, market, credit and correlation risk. In addition, derivatives can create economic leverage in the fund’s portfolio, which may result in significant volatility and cause the fund to participate in losses (as well as gains) in an amount that exceeds the fund’s initial investment. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment.
Futures contracts may experience dramatic price changes and imperfect correlations between the price of the contract and the underlying security, index or currency.
Swap agreements subject a fund to the risk that the counterparty to the transaction may not meet its obligations. The fund also bears the risk of loss of the amount expected to be received under a swap agreement in the event of the default or bankruptcy of a counterparty. Swap agreements may also be considered illiquid.
Foreign currency forward contracts and other derivatives contracts on foreign currencies involve a risk of loss if currency exchange rates move against the fund’s position.

Bank Loan Risk – The market for bank loans may not be highly liquid and the fund may have difficulty selling them. In connection with purchasing loan participations, the fund generally will have no right to enforce compliance by borrowers with loan terms nor any set off rights, and the fund may not benefit directly from any posted collateral. As a result, the fund may be subject to the credit risk of both the borrower and the lender selling the participation. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional investments or meet redemptions. To the extent the extended loan settlement process gives rise to short-term liquidity needs, such as the need to satisfy redemption requests, the fund may hold cash or sell investments.
Collateralized Debt Obligations Risk – Collateralized debt obligations and collateralized loan obligations (CLOs) are subject to credit, interest rate, valuation, and prepayment and extension risks. These securities also are subject to risk of default on the underlying asset, particularly during periods of economic downturn. The market value of CLOs may be affected by, among other things, changes in the market value of the underlying assets held by the CLO, changes in the distributions on the underlying assets, defaults and recoveries on the underlying assets, capital gains and losses on the underlying assets, prepayments on underlying assets and the availability, prices and interest rate of underlying assets. Lower rated tranches of such debt are subject to a higher risk of total loss and deferral or nonpayment of interest than the more senior tranches to which they are subordinated.
Convertible Securities Risk – The value of convertible securities may rise and fall with the market value of the underlying stock or, like a debt security, vary with changes in interest rates and the credit quality of the issuer. A convertible security tends to perform more like a stock when the underlying stock price is high relative to the conversion price and more like a debt security when the underlying stock price is low relative to the conversion price.
Preferred Securities Risk – Preferred securities combine some of the characteristics of both common stocks and bonds. Preferred securities are typically subordinated to a company’s other debt which subjects them to greater credit risk . Generally, holders of preferred securities have no voting rights. In certain circumstances, an issuer of preferred securities may defer payment on the securities and, in some cases, redeem the securities prior to a specified date. Preferred securities may also be substantially less liquid than other securities and may have less upside potential than common stock.
Counterparty Risk – If the fund enters into financial contracts, the fund will be subject to the credit risk presented by the counterparties.
Cash Transactions Risk - The fund may effect its creations and redemptions for cash, rather than for in-kind securities. Therefore, it may be required to sell portfolio securities and subsequently recognize gains on such sales that the fund might not have recognized if it were to distribute portfolio securities in-kind. As such, investments in fund shares may be less tax-efficient than an investment in an ETF that distributes portfolio securities entirely in-kind. Cash transactions may have to be carried out over several days if the securities market is relatively illiquid and may involve considerable brokerage fees and taxes. Brokerage fees and taxes will be higher than if the fund sold and redeemed shares in-kind.
Liquidity Risk - During periods of market turbulence or unusually low trading activity, it may be necessary for the fund to sell securities at prices that could have an adverse effect on the fund. The market for lower-quality debt securities is generally less liquid than the market for higher-quality securities. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
High Portfolio Turnover Risk - The fund may engage in active and frequent trading of its portfolio securities. High portfolio turnover may result in increased transaction costs to the fund, including brokerage commissions, dealer mark-ups and other transaction costs on the sale of the securities and on reinvestment in other securities.
Market Trading Risk - The fund faces numerous market trading risks, including the potential lack of an active market for fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation and/or redemption process of the fund. Any of these factors, among others, may lead to the fund’s shares trading at a premium or discount to NAV. Thus, you may pay more (or less) than NAV when you buy shares of the fund in the secondary market, and you may receive less (or more) than NAV when you sell those shares in the secondary market. The portfolio managers cannot predict whether shares will trade above (premium), below (discount) or at NAV.
Market Risk - The value of the fund’s shares will go up and down, sometimes rapidly or unpredictably, based on the performance of the issuers whose securities it owns and other factors generally affecting the securities market. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
Prepayment and Extension Risk -The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds of similar duration that invest less heavily in mortgage and asset-backed securities. Conversely, an issuer may exercise its right to pay principal on an obligation held by the fund later than expected (extend the obligation) especially in periods of rising interest rates. These events may lengthen the duration (i.e. interest rate sensitivity) and potentially reduce the value of these securities.

Public Health Emergency Risk - A pandemic, caused by the infectious respiratory illness COVID-19, is causing market disruption and other economic impacts. Markets have experienced volatility, reduced liquidity, and increased trading costs. These events may continue to impact the fund and its underlying investments and could cause increased premiums or discounts to the fund’s NAV.
Authorized Participant Concentration Risk - Only an authorized participant may engage in creation or redemption transactions directly with the fund. The fund may have a limited number of institutions that act as authorized participants. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the fund and no other authorized participant is able to step forward to process creation and/or redemption orders, fund shares may trade at a discount to net asset value (NAV) and possibly face trading halts and/or delisting. This risk may be more pronounced in volatile markets, potentially where there are significant redemptions in ETFs generally.
Large Shareholder Risk - Certain shareholders, including other funds advised by the advisor, may from time to time own a substantial amount of the shares of the fund. In addition, a third party investor, the advisor or an affiliate of the advisor, an authorized participant, a market maker, or another entity may invest in the fund and hold its investment for a limited period of time solely to facilitate commencement of the fund or to facilitate the fund’s achieving a specified size or scale. There can be no assurance that any large shareholder would not redeem its investment, that the size of the fund would be maintained at such levels or that the fund would continue to meet applicable listing requirements. Redemptions by large shareholders could have a significant negative impact on the fund. In addition, transactions by large shareholders may account for a large percentage of the trading volume on the NYSE Arca, Inc. and may, therefore, have a material upward or downward effect on the market price of the shares.
Principal Loss Risk - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.
An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
Fund Performance
The fund’s performance history is not available as of the date of this prospectus. When the fund has investment results for a full calendar year, this section will feature charts that show annual total returns, highest and lowest quarterly returns and average annual total returns for the fund. This information indicates the volatility of the fund’s historical returns from year to year. For current performance information, please visit americancenturyetfs.com.
Performance information is designed to help you see how fund returns can vary. Keep in mind that past performance (before and after taxes) does not predict how the fund will perform in the future.
Portfolio Management
Investment Advisor
American Century Investment Management, Inc.
Portfolio Managers
Charles Tan, Senior Vice President and Co-Chief Investment Officer, Global Fixed Income, has served on teams managing fixed-income investments since joining the advisor in 2018.
Jason Greenblath, Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments since joining the advisor in 2019.
Jeffrey L. Houston, CFA, Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments since joining the advisor in 1990.
Purchase and Sale of Fund Shares
The fund is an ETF. Fund shares may only be bought and sold in a secondary market through a broker-dealer at a market price. Because ETF 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). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the fund (bid) and the lowest price a seller is willing to accept for shares of the fund (ask) when buying or selling shares in the secondary market (bid-ask spread). Investors can find information on the fund’s NAV, market price, premiums and discounts, and bid-ask spread at americancenturyetfs.com.
Tax Information
Fund distributions are generally taxable as ordinary income or capital gains, unless you are investing through a tax-deferred account such as a 401(k) or individual retirement account (in which case you may be taxed upon withdrawal of your investment from such account).

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

©2021 American Century Proprietary Holdings, Inc. All rights reserved.
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