N-1A/A 1 acetft1818n-1aa.htm N-1A/A Document
As Filed with the U.S. Securities and Exchange Commission on January 8, 2018
1933 Act File No. 333-221045
1940 Act File No. 811-23305
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
__________________
 
FORM N-1A
__________________
 
 
REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
 
 
Pre-Effective Amendment No. 2
 
 
Post-Effective Amendment No.
 
 
and/or
 
 
REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940
 
 
Amendment No. 2
(Check appropriate box or boxes.)
__________________
American Century ETF Trust
__________________
4500 MAIN STREET, KANSAS CITY, MISSOURI 64111
  (Address of Principal Executive Offices)                  (Zip Code)   
 
REGISTRANT’S TELEPHONE NUMBER, INCLUDING AREA CODE: (816) 531-5575
CHARLES A. ETHERINGTON
4500 MAIN STREET, KANSAS CITY, MISSOURI 64111
(Name and Address of Agent for Service)
 
Approximate Date of Proposed Public Offering: As soon as practicable after the effective date of the registration statement.
 
 
The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment that specifically states that the registration statement shall thereafter become effective in accordance with section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said section 8(a), may determine.




The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

[January 9, 2018]

American Century Investments
Prospectus

 
Ticker:
Exchange:
American Century STOXX® U.S. Quality Value ETF
VALQ
NYSE Arca, Inc.
















The Securities and Exchange Commission has
not approved or disapproved these securities or
passed upon the adequacy of this prospectus. Any
representation to the contrary is a criminal offense.
acietfslockupblacka01.jpg





Table of Contents

Fund Summary
2

Investment Objective
2

Fees and Expenses
2

Principal Investment Strategies
2

Principal Risks
3

Fund Performance
4

Portfolio Management
4

Purchase and Sale of Fund Shares
4

Tax Information
4

Payments to Broker-Dealers and Other Financial Intermediaries
4

Objectives, Strategies and Risks
5

Management
7

Investing in the Fund
8

Share Price and Distributions
9

Taxes
11

Additional Information
12

Index Provider
13

Disclaimers
13

Financial Highlights
13
























© 2018 American Century Proprietary Holdings, Inc. All rights reserved.




Fund Summary
Investment Objective
The fund seeks to provide investment results that closely correspond, before fees and expenses, to the performance of the iSTOXX® American Century USA Quality Value Index (the underlying index).
Fees and Expenses
The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. You may also incur usual and customary brokerage commissions when buying or selling shares of the fund, which are not reflected in the example that follows.
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fee
0.29%
Other Expenses1
0.00%
Total Annual Fund Operating Expenses
0.29%
1Other expenses are based on estimated amounts for the current fiscal year.
Example
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 (unless otherwise indicated), that you earn a 5% return each year, and that the fund’s operating expenses remain the same. You may be required to pay brokerage commissions on your purchases of shares of the fund, which are not reflected in the example. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 year
3 years
$30
$93
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
Under normal market conditions, the fund invests at least 80% of its assets in the component securities of the underlying index. The underlying index is a rules-based index maintained and calculated by STOXX® Ltd. (the index provider). The underlying index is designed to select securities of large- and mid-capitalization companies that are undervalued or have sustainable income.
The underlying index universe is defined by the STOXX® USA 900 Index, which consists of the 900 largest publicly traded U.S. equity securities. The underlying index is constructed using a rules-based methodology that screens and weights stocks based on fundamental measures of quality, value and income. A quality screen seeks to eliminate the bottom of the universe of stocks based on measures of profitability, earnings quality, management quality and earnings estimate revisions. A valuation score is computed for the remaining stocks, determined by the attractiveness of each stock relative to its peers in the same industry group based on value, earnings yield and cash flow yield metrics. An income sustainability screen based on dividend growth and dividend coverage metrics is applied to eliminate the bottom of the universe of dividend-paying stocks, and an income score based on dividend-yield is computed for the remaining stocks. The underlying index is constructed by combining the value stocks and income stocks using the valuation and income scores and portfolio optimization. Portfolio optimization uses quantitative models to build a portfolio of stocks from the scores described above that are expected to provide the optimal balance between risk and expected return. Though component securities of the underlying index may change from time to time, the index typically consists of 200-300 securities and, as of December 20, 2017 the market capitalization range was approximately $2 billion to $880 billion.
The fund may use a “representative sampling” strategy with respect to its underlying index when a replication strategy might be detrimental to shareholders. For example, the fund may use such strategy when there are practical difficulties or substantial costs involved in compiling a portfolio of securities to follow the underlying index or, in certain instances, when a component security becomes temporarily illiquid, unavailable or less liquid. To the extent the fund uses representative sampling, the advisor invests in what it believes to be a representative sample of the component securities in the underlying index using quantitative analytical procedures to give the fund's portfolio an investment profile similar to that of its underlying index. The fund also may realize savings in transaction costs or other efficiencies by investing up to 20% of its assets in securities or instruments not included in the underlying index but which the advisor believes will help the fund track the underlying index.

2



In addition, the fund may use futures contracts to equitize cash and accrued income, simulate investments in the underlying index, facilitate trading or minimize transaction costs. Through the use of futures contracts, the advisor seeks to reduce the fund’s tracking error relative to the underlying index.
The underlying index is rebalanced monthly and reconstituted quarterly.
The fund will concentrate its investments (i.e., hold 25% or more of its net assets) in a particular industry or group of industries to approximately the same extent that the underlying index is concentrated.
Principal Risks
Authorized Participant Concentration - Only an authorized participant may engage in creation or redemption transactions directly with the fund. The fund has 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 exchange-traded funds (ETFs) generally.
Calculation Methodology - The underlying index relies on various sources of information to assess the criteria of issuers included in the underlying index, including information that may be based on assumptions and estimates. Neither the fund nor American Century Investment Management, Inc. (the advisor) can offer assurances that the underlying index’s calculation methodology or sources of information will provide an accurate assessment of included issuers.
Concentration - To the extent the fund concentrates in a specific industry or a group of industries, it may be subject to greater risks and market fluctuations than a portfolio investing in a broader range of industries.
Derivatives Risk - The use of derivative instruments such as futures contracts involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. 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.
Index-Related - Unlike many investment companies, the fund is not actively managed and the portfolio managers do not attempt to take defensive positions under any market conditions, including declining markets. Therefore, the portfolio managers would not necessarily buy or sell a security unless that security is added or removed, respectively, from the underlying index, even if that security generally is underperforming.
There is no assurance that the underlying index will be determined, composed or calculated accurately. While the index provider provides descriptions of what the underlying index is designed to achieve, the index provider does not guarantee the quality, accuracy or completeness of data in respect of its indices, and does not guarantee that the underlying index will be in line with the described index methodology. Gains, losses or costs to the fund caused by errors in the underlying index may therefore be borne by the fund and its shareholders.
Management Risk - To the extent the fund uses representative sampling, the strategy may fail to produce the intended results.
Market Risk - The value of the fund’s shares will go up and down, sometimes rapidly or unpredictably, based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.
Market Trading - 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.
Mid Cap Stocks - The fund invests in medium-sized companies, which may be more volatile and subject to greater risk than larger companies. Medium-sized companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.
New Fund Risk - As a new fund, there can be no assurance that it will grow to or maintain an economically viable size. The fund may experience greater tracking error than it otherwise would at higher asset levels.
Non-Correlation - There is no guarantee that the fund will achieve a high degree of correlation to the underlying index and therefore achieve its investment objective. Market disruptions and regulatory restrictions could have an adverse effect on the fund’s ability to adjust its exposure to the required levels in order to track the underlying index. In addition, the fund’s NAV may deviate from the underlying index if the fund fair values a portfolio security at a price other than the price used by the underlying index for that security.

3



Sampling Risk- To the extent the fund uses a representative sampling strategy, it may hold a smaller number of securities than are in the underlying index or it may hold securities that are not included in the underlying index. As a result, an adverse development respecting an issuer of securities held by the fund could result in a greater decline in the fund’s NAV than would be the case if all of the securities in the underlying index were held. The fund’s use of a representative sampling strategy may also include the risk that it may not track the return of the underlying index with the same degree of accuracy as would an investment vehicle that invested in every component security of the underlying index with the same weightings as the underlying index.
Style Risk - There can be no assurance that the investment factor stock selection process and screens of the underlying index will enhance performance. Exposure to certain investment factors and use of screens may detract from performance in some market environments, perhaps for extended periods.
Tracking Error - Tracking error is the divergence of the fund’s performance from that of the underlying index. Tracking error may occur because of differences between the securities held in the fund’s portfolio and those included in the underlying index, pricing differences, transaction costs, the fund’s holding of cash, differences in timing of the accrual of dividends or interest, changes to the underlying index or the need to meet various new or existing regulatory requirements. This risk may be heightened during times of increased market volatility or other unusual market conditions. Tracking error also may result because the fund incurs fees and expenses, while the underlying index does not.
Principal Loss - 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
Peruvemba Satish, Ph.D, CFA, Senior Vice President, Portfolio Manager and Director, Global Analytics, has been a member of the team that manages the fund since 2018.
Rene P. Casis , Portfolio Manager, has been a member of the team that manages the fund since 2018.
Purchase and Sale of Fund Shares
The fund is an ETF. Fund shares may only be purchased and sold on a national securities exchange through a broker-dealer. The price of fund shares is based on market price, and 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). The fund issues and redeems shares that have been aggregated into blocks of 25,000 shares or multiples thereof (Creation Units) to authorized participants who have entered into agreements with the fund’s distributor. The fund will generally issue and redeem Creation Units in return for a basket of securities (and an amount of cash) that the fund specifies each day.
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.


4



Objectives, Strategies and Risks
What are the fund’s investment objectives?
The fund seeks to provide investment results that closely correspond, before fees and expenses, to the performance of the underlying index.
The fund’s investment objective is a nonfundamental investment policy and may be changed by the Board of Trustees without approval by shareholders upon 60 days’ prior notice to shareholders.
What are the fund’s principal investment strategies?
Under normal market conditions, the fund invests at least 80% of its assets in the component securities of the underlying index. The underlying index is a rules-based index maintained and calculated by STOXX® Ltd. (the index provider). The underlying index is designed to select securities of large- and mid-capitalization companies that are undervalued or have sustainable income.
The underlying index universe is defined by the STOXX® USA 900 Index, which consists of the 900 largest publicly traded U.S. equity securities. The underlying index is constructed using a rules-based methodology that screens and weights stocks based on fundamental measures of quality, value and income. A quality screen seeks to eliminate the bottom of the universe of stocks based on measures of profitability, earnings quality, management quality and earnings estimate revisions. Earnings estimate revisions refer to changes in analysts’ estimates of a company’s earnings. A valuation score is computed for the remaining stocks, determined by the attractiveness of each stock relative to its peers in the same industry group based on value, earnings yield and cash flow yield metrics. An income sustainability screen based on dividend growth and dividend coverage metrics is applied to eliminate the bottom universe of dividend-paying stocks, and an income score based on dividend-yield is computed for the remaining stocks. The underlying index is constructed by combining the value stocks and income stocks using the valuation and income scores and portfolio optimization. Portfolio optimization uses quantitative models to build a portfolio of stocks from the scores described above that are expected to provide the optimal balance between risk and expected return. Though component securities of the underlying index may change from time to time, the index typically consists of 200-300 securities and, as of December 20, 2017, the market capitalization range was approximately $2 billion to $880 billion.
The fund may use a “representative sampling” strategy with respect to its underlying index when a replication strategy might be detrimental to shareholders. For example, the fund may use such strategy when there are practical difficulties or substantial costs involved in compiling a portfolio of securities to follow the underlying index or, in certain instances, when a component security becomes temporarily illiquid, unavailable or less liquid. To the extent the fund uses representative sampling, the advisor invests in what it believes to be a representative sample of the component securities in the underlying index using quantitative analytical procedures to give the fund's portfolio an investment profile similar to that of its underlying index. The fund also may realize savings in transaction costs or other efficiencies by investing up to 20% of its assets in securities or instruments not included in the underlying index but which the advisor believes will help the fund track the underlying index.
In addition, the fund may use futures contracts to equitize cash and accrued income, simulate investments in the underlying index, facilitate trading or minimize transaction costs. Through the use of futures contracts, the advisor seeks to reduce the fund’s tracking error relative to the underlying index.
The underlying index is rebalanced monthly and reconstituted quarterly.
The fund will concentrate its investments (i.e., hold 25% or more of its net assets) in a particular industry or group of industries to approximately the same extent that the underlying index is concentrated.
A description of the policies and procedures with respect to the disclosure of the fund’s portfolio securities is available in the statement of additional information.
What are the principal risks of investing in the fund?
Authorized Participant Concentration - Only an authorized participant may engage in creation or redemption transactions directly with the fund. The fund has 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 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.
Calculation Methodology - The underlying index relies on various sources of information to assess the criteria of issuers included in the underlying index, including information that may be based on assumptions and estimates. Neither the fund nor the advisor can offer assurances that the underlying index’s calculation methodology or sources of information will provide an accurate assessment of included issuers.
Concentration - To the extent the fund concentrates in a specific industry or a group of industries, it may be subject to greater risks and market fluctuations than a portfolio investing in a broader range of industries.

5



Derivatives Risk - The use of derivative instruments such as futures contracts involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks, including liquidity, interest rate, market, and credit risk. They also involve the risk of mispricing or improper valuation, the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index, and the risk of default or bankruptcy of the other party to the instrument. Gains or losses involving futures may be substantial - in part because a relatively small price movement in these securities may result in an immediate and substantial gain or loss for the fund. 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.
Index-Related - Unlike many investment companies, the fund is not actively managed and the portfolio managers do not attempt to take defensive positions under any market conditions, including declining markets. Therefore, the portfolio managers would not necessarily buy or sell a security unless that security is added or removed, respectively, from the underlying index, even if that security generally is underperforming.
There is no assurance that the underlying index will be determined, composed or calculated accurately. While the index provider provides descriptions of what the underlying index is designed to achieve, the index provider does not guarantee the quality, accuracy or completeness of data in respect of its indices, and does not guarantee that the underlying index will be in line with the described index methodology. Gains, losses or costs to the fund caused by errors in the underlying index may therefore be borne by the fund and its shareholders.
Management Risk - To the extent the fund uses representative sampling, the strategy may fail to produce the intended results.
Market Risk - The value of the fund’s shares depends on the value of the stocks and other securities it owns. The value of the individual securities the fund owns will go up and down, sometimes rapidly or unpredictably, depending on the performance of the companies that issued them, general market and economic conditions and investor confidence.
Market Trading - Although shares of the fund are listed for trading on one or more stock exchanges, there can be no assurance that an active trading market for such shares will develop or be maintained. There are no obligations of market makers to make a market in the fund’s shares or of an authorized participant to submit purchase or redemption orders for Creation Units. Decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying value of the fund’s portfolio securities and the fund’s market price. This reduced effectiveness could result in fund shares trading at a premium or discount to its NAV and also greater than normal intraday bid/ask spreads.
Shares of the fund may trade in the secondary market at times when the fund does not accept orders to purchase or redeem shares. At such times, shares may trade in the secondary market with more significant premiums or discounts than might be experienced at times when the fund accepts purchase and redemption orders. Secondary market trading in fund shares may be halted by a stock exchange because of market conditions or other reasons, and may be subject to trading halts caused by extraordinary market volatility pursuant to “circuit breaker” rules on the stock exchange or market. There can be no assurance that the requirements necessary to maintain the listing or trading of fund shares will continue to be met or will remain unchanged. In addition, during a “flash crash,” the market prices of the fund’s shares may decline suddenly and significantly. Such a decline may not reflect the performance of the portfolio securities held by the fund. Flash crashes may cause authorized participants and other market makers to limit or cease trading in the fund’s shares for temporary or longer periods. Shareholders could suffer significant losses to the extent that they sell fund shares at these temporarily low market prices.
Shares of the fund may trade at prices other than 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. While the creation/redemption feature is designed to make it likely that the fund’s shares normally will trade on stock exchanges at prices close to the fund’s next calculated NAV, market prices are not expected to correlate exactly with the fund’s NAV due to timing reasons as well as market supply and demand factors. In addition, disruptions to creations and redemptions or extreme market volatility may result in trading prices for shares of the fund that differ significantly from its NAV. The portfolio managers cannot predict whether shares will trade above (premium), below (discount) or at NAV.
When buying or selling shares of the fund through a broker, you will likely incur a brokerage commission or other charges determined by your broker. In addition, you may incur the cost of the “spread,” that is, any difference between the bid price and the ask price. The spread varies over time for shares of the fund based on the fund’s trading volume and market liquidity, and is generally lower if the fund has a lot of trading volume and market liquidity, and higher if the fund has little trading volume and market liquidity. During times of market stress, spreads may widen causing investors to pay more.
Mid Cap Stocks - The fund invests in medium-sized companies, which may be more volatile and subject to greater risk than larger companies. Medium-sized companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies. In addition, medium-sized companies may have less publicly available information than larger companies.

6



New Fund Risk - As a new fund, there can be no assurance that it will grow to or maintain an economically viable size. The fund may experience greater tracking error than it otherwise would at higher asset levels.
Non-Correlation - There is no guarantee that the fund will achieve a high degree of correlation to the underlying index and therefore achieve its investment objective. Market disruptions and regulatory restrictions could have an adverse effect on the fund’s ability to adjust its exposure to the required levels in order to track the underlying index. In addition, the fund’s NAV may deviate from the underlying index if the fund fair values a portfolio security at a price other than the price used by the underlying index for that security.
Sampling Risk - To the extent the fund uses a representative sampling strategy, it may hold a smaller number of securities than are in the underlying index or it may hold securities that are not included in the underlying index. As a result, an adverse development respecting an issuer of securities held by the fund could result in a greater decline in the fund’s NAV than would be the case if all of the securities in the underlying index were held. The fund’s use of a representative sampling strategy may also include the risk that it may not track the return of the underlying index with the same degree of accuracy as would an investment vehicle that invested in every component security of the underlying index with the same weightings as the underlying index.
Style Risk - There can be no assurance that the investment factor stock selection process and screens of the underlying index will enhance performance. Exposure to certain investment factors and use of screens may detract from performance in some market environments, perhaps for extended periods.
Tracking Error - Tracking error is the divergence of the fund’s performance from that of the underlying index. Tracking error may occur because of differences between the securities held in the fund’s portfolio and those included in the underlying index, pricing differences, transaction costs, the fund’s holding of cash, differences in timing of the accrual of dividends or interest, changes to the underlying index or the need to meet various new or existing regulatory requirements. This risk may be heightened during times of increased market volatility or other unusual market conditions. Tracking error also may result because the fund incurs fees and expenses, while the underlying index does not.
Principal Loss - 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.
Management
Who manages the fund?
The Board of Trustees, investment advisor and fund management team play key roles in the management of the fund.
The Board of Trustees
The Board of Trustees is responsible for overseeing the advisor’s management and operations of the fund pursuant to the management agreement. In performing their duties, Board members receive detailed information about the fund and its advisor regularly throughout the year, and meet at least quarterly with management of the advisor to review reports about fund operations. The trustees’ role is to provide oversight and not to provide day-to-day management. The majority of the trustees are independent of the fund’s advisor. They are not employees, directors or officers of, and have no financial interest in, the advisor or any of its affiliated companies (other than as shareholders of American Century Investments funds), and they do not have any other affiliations, positions or relationships that would cause them to be considered “interested persons” under the Investment Company Act of 1940 (Investment Company Act).
The Investment Advisor
The fund’s investment advisor is American Century Investment Management, Inc. (the advisor). The advisor has been managing investment companies since 1958 and is headquartered at 4500 Main Street, Kansas City, Missouri 64111.
The advisor is responsible for managing the investment portfolio of the fund and directing the purchase and sale of its investment securities. The advisor also arranges for transfer agency, custody and all other services necessary for the fund to operate.
For the services it provides to the fund, the advisor receives a unified management fee based on a percentage of the daily net assets of the fund at the annual rate of 0.29%. The amount of the fee is calculated daily and paid monthly in arrears. The advisor pays all expenses of managing and operating the fund, other than the management fee payable to the advisor, brokerage and other transaction fees and expenses relating to the acquisition and disposition of portfolio securities, acquired fund fees and expenses, interest, taxes, litigation expenses, extraordinary expenses, and expenses incurred in connection with the provision of shareholder and distribution services under a plan adopted pursuant to Rule 12b-1 under the Investment Company Act (if any). The advisor may pay unaffiliated third parties who provide recordkeeping and administrative services that would otherwise be performed by an affiliate of the advisor.
A discussion regarding the basis for the Board of Trustees’ approval of the fund’s investment advisory agreement with the advisor will be available in the fund’s semiannual report to shareholders for the period ended February 28, 2018.
The Fund Management Team
The portfolio managers buy and sell securities for the fund pursuant to an indexing investment approach; therefore, team members will not necessarily buy or sell a security unless that security is added to or removed from, respectively, the underlying index.

7



The portfolio managers on the investment team who are jointly and primarily responsible for the day-to-day management of the fund are identified below.
Peruvemba Satish
Mr. Satish, Senior Vice President, Portfolio Manager and Director, Global Analytics, joined American Century in 2014. He became a portfolio manager in 2017 and has been a member of the team that manages the fund since 2018. Prior to joining American Century, he served from 2010 to 2014 in roles as managing director and senior managing director at Allstate Investment Management Co. He has a bachelor’s degree and master’s degree in mechanical engineering and economics from Birla Institute of Technology & Science, a master’s degree in economics from State University of New York and a Ph.D in finance from the University of Texas at Austin. He is a CFA charterholder.
Rene P. Casis
Mr. Casis, Portfolio Manager, has been a member of the team that manages the fund since joining American Century in 2018. Prior to joining American Century, he was a Partner at 55 Institutional, LLC from 2016 to 2017. From 2009 to 2016, he served in roles as US iShares Smart Beta Investment Strategist, US iShares Product Strategist and Senior Portfolio Manager in Beta Strategies for BlackRock Inc. He has a bachelor’s degree in economics from the University of California, Santa Barbara.
The statement of additional information provides additional information about the accounts managed by the portfolio managers, the structure of their compensation, and their ownership of fund securities.
Fundamental Investment Policies
Shareholders must approve any change to the fundamental investment policies contained in the statement of additional information. The Board of Trustees and/or the advisor may change any other policies, including the fund’s investment objective, or investment strategies described in this prospectus or otherwise used in the operation of the fund at any time, subject to applicable notice provisions.

Investing in the Fund
Buying and Selling Shares
Shares of the fund may be acquired or redeemed directly from the fund only in Creation Units or multiples thereof, as discussed below. Only an authorized participant may engage in creation and redemption transactions directly with the fund. Once created, shares of the fund generally trade in the secondary market in amounts less than a Creation Unit.
Shares of the fund are listed on a national securities exchange for trading during the trading day. Shares can be bought and sold throughout the trading day like shares of other publicly traded companies. American Century ETF Trust (the trust) does not impose any minimum investment for shares of the fund purchased on an exchange. Shares of the fund trade under the following ticker symbol: VALQ.
Buying or selling fund shares on an exchange involves two types of costs that may apply to all securities transactions. When buying or selling shares of the fund through a broker, you will likely incur a brokerage commission or other charges determined by your broker. The commission is frequently a fixed amount and may be a significant proportional cost for investors seeking to buy or sell small amounts of shares. In addition, you may incur the cost of the “spread,” that is, any difference between the bid price and the ask price. The spread varies over time for shares of the fund based on the fund’s trading volume and market liquidity, and is generally lower if the fund has a lot of trading volume and market liquidity, and higher if the fund has little trading volume and market liquidity.
The fund’s primary listing exchange is NYSE Arca, Inc., which is open for trading Monday through Friday and is closed on weekends and the following holidays: New Year’s Day, Martin Luther King, Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day.
Book Entry
Shares of the fund are held in book-entry form, which means that no share certificates are issued. The Depository Trust Company (DTC) or its nominee is the record owner of all outstanding shares of the fund and is recognized as the owner of all shares for all purposes.
Investors owning shares of the fund are beneficial owners as shown on the records of DTC or its participants. DTC serves as the securities depository for shares of the fund. DTC participants include securities brokers and dealers, banks, trust companies, clearing corporations and other institutions that directly or indirectly maintain a custodial relationship with DTC. As a beneficial owner of shares, you are not entitled to receive physical delivery of stock certificates or to have shares registered in your name, and you are not considered a registered owner of shares. Therefore, to exercise any right as an owner of shares, you must rely upon the procedures of DTC and its participants. These procedures are the same as those that apply to any other securities that you hold in book-entry or “street name” form.

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Frequent Trading Practices
The Board of Trustees has not adopted a policy of monitoring for frequent purchases and redemptions of fund shares (frequent trading). The Board of Trustees believes that a frequent trading policy is unnecessary because fund shares are listed for trading on a national securities exchange. Therefore, it is unlikely that a shareholder could take advantage of a potential arbitrage opportunity presented by a lag between a change in the value of the fund’s portfolio securities after the close of the primary markets for the fund’s portfolio securities and the reflection of that change in the fund’s NAV (market timing), because the fund generally sells and redeems its shares directly through transactions that are in-kind and/or for cash, subject to the conditions described below under Creations and Redemptions.
Investments by Other Investment Companies
Section 12(d)(1) of the Investment Company Act restricts investments by investment companies in the securities of other investment companies. Registered investment companies are permitted to invest in the fund beyond the limits set forth in Section 12(d)(1), subject to certain terms and conditions set forth in SEC rules or in an SEC exemptive order issued to the trust. In order for a registered investment company to invest in shares of the fund beyond the limitations of Section 12(d)(1) pursuant to the exemptive relief obtained by the trust, the registered investment company must enter into an agreement with the trust.
Creations and Redemptions
Prior to trading in the secondary market, shares of the fund are “created” at NAV by market makers, large investors and institutions only in block-size Creation Units of 25,000 shares or multiples thereof. All orders to purchase Creation Units must be placed by or through an authorized participant that has entered into an authorized participant agreement (AP Agreement) with Foreside Fund Services, LLC (the distributor). Only an authorized participant may create or redeem Creation Units directly with the fund.
A creation transaction, which is subject to acceptance by the trust, generally takes place when an authorized participant deposits into the fund a designated portfolio of securities and/or cash (which may include cash in lieu of certain securities) in exchange for a specified number of Creation Units. Similarly, shares can be redeemed only in Creation Units, generally for a designated portfolio of securities and/or cash (which may include cash in lieu of certain securities). Except when aggregated in Creation Units, shares are not redeemable by the fund.
The prices at which creations and redemptions occur are based on the next calculation of NAV after a creation or redemption order is received in an acceptable form under the AP Agreement. The portfolio of securities required for purchase of a Creation Unit is generally the same as the portfolio of securities the fund will deliver upon redemption of fund shares, except under certain circumstances. The designated portfolio of securities in connection with a purchase or redemption of a Creation Unit generally will correspond pro rata, except under certain circumstances, to the securities held by the fund. As a result of any system failure or other interruption, creation or redemption orders either may not be executed according to the fund’s instructions or may not be executed at all, or the fund may not be able to place or change such orders.
Creations and redemptions must be made through a firm that is either a broker-dealer or other participant in the Continuous Net Settlement System of the National Securities Clearing Corporation or a DTC participant and, in either case, has executed an AP Agreement with the distributor. Information about the procedures regarding creations and redemptions of Creation Units (including the cut-off times for receipt of creation and redemption orders) is included in the fund’s statement of additional information (SAI).
Because new shares may be created and issued on an ongoing basis, at any point during the life of the fund a “distribution,” as such term is used in the Securities Act of 1933 (Securities Act), may be occurring. Broker-dealers and other persons are cautioned that some activities on their part may, depending on the circumstances, result in their being deemed participants in a distribution in a manner that could render them statutory underwriters and subject to the prospectus delivery and liability provisions of the Securities Act. Any determination of whether one is an underwriter must take into account all the relevant facts and circumstances of each particular case.
Broker-dealers should also note that dealers who are not “underwriters” but are participating in a distribution (as contrasted to ordinary secondary transactions), and thus dealing with shares that are part of an “unsold allotment” within the meaning of Section 4(a)(3)(C) of the Securities Act, would be unable to take advantage of the prospectus delivery exemption provided by Section 4(a)(3) of the Securities Act. For delivery of prospectuses to exchange members, the prospectus delivery mechanism of Rule 153 under the Securities Act is available only with respect to transactions on a national securities exchange.

Share Price and Distributions
Share Price
The trading prices of the fund’s shares in the secondary market generally differ from the fund’s daily NAV and are affected by market forces such as supply and demand, economic conditions and other factors. Information regarding the intraday value of shares of the fund, also known as the “indicative optimized portfolio value” (IOPV), is disseminated every 15 seconds throughout the trading day by the national securities exchange on which the fund’s shares are listed or by market data vendors or other information providers. The IOPV is based on the current market value of the securities and/or cash required to be deposited in exchange for a creation unit. The

9



IOPV does not necessarily reflect the best possible valuation of the current portfolio of securities held by the fund, and may not be calculated in the same manner as the NAV. Therefore, the IOPV should not be viewed as a “real-time” update of the fund’s NAV, which is computed only once a day as described below. The IOPV is generally determined by using both current market quotations and/or price quotations obtained from broker-dealers that may trade in the portfolio securities held by the fund. The fund, the advisor and their related entities are not involved in, or responsible for, the calculation or dissemination of the IOPV and make no representation or warranty as to its accuracy.
Calculation of NAV
American Century Investments will price the fund shares purchased or redeemed by authorized participants based on the net asset value (NAV) next determined after an order is received in good order by the fund’s transfer agent. We determine the NAV of the fund as of the close of regular trading (usually 4 p.m. Eastern time) on the New York Stock Exchange (NYSE) on each day the NYSE is open. On days when the NYSE is closed (including certain U.S. national holidays), we do not calculate the NAV.
 
The net asset value, or NAV, of the fund is the current value of the fund’s assets, minus any liabilities, divided by the number of shares of the fund outstanding.
 
The fund values portfolio securities for which market quotations are readily available at their market price. As a general rule, equity securities listed on a U.S. exchange are valued at the last reported sale price as of the time of valuation. Securities that are neither listed on a securities exchange or traded over the counter may be priced using the mean of the bid and asked prices obtained from an independent broker who is an established market maker in the security. The fund may use third party pricing services to assist in the determination of market value.
If the fund determines that the market price for a portfolio security is not readily available or that the valuation methods mentioned above do not reflect the security’s fair value, such security is valued as determined in good faith by the fund’s board or its designee, in accordance with procedures adopted by the fund’s board. Circumstances that may cause the fund to use alternate procedures to value a security include, but are not limited to:
if, after the close of the foreign exchange on which a portfolio security is principally traded, but before the close of the NYSE, an event occurs that may materially affect the value of the security;
a debt security has been declared in default; or
trading in a security has been halted during the trading day.
If such circumstances occur, the fund will fair value the security if the fair valuation would materially impact the fund’s NAV. While fair value determinations involve judgments that are inherently subjective, these determinations are made in good faith in accordance with procedures adopted by the fund’s board.
The effect of using fair value determinations is that the fund’s NAV will be based, to some degree, on security valuations that the board or its designee believes are fair rather than being solely determined by the market. Use of fair value prices and certain current market valuations, however, could result in a difference between the prices used to calculate the fund’s NAV and the prices used by the underlying index, which, in turn, could result in a difference between the fund’s performance and the performance of the underlying index and introduce tracking error.
With respect to any portion of the fund’s assets that are invested in one or more open-end management investment companies that are registered with the SEC (known as registered investment companies), the fund’s NAV will be calculated based upon the NAVs of such registered investment companies. These registered investment companies are required by law to explain the circumstances under which they will use fair value pricing and the effects of using fair value pricing in their prospectuses.
Trading of securities in foreign markets may not take place every day the NYSE is open. Also, trading in some foreign markets and on some electronic trading networks may take place on weekends or holidays when the fund’s NAV is not calculated. So, the value of the fund’s portfolio may be affected on days when you will not be able to purchase or sell fund shares.
Distributions
Federal tax laws require the fund to make distributions to its shareholders in order to qualify as a regulated investment company. Qualification as a regulated investment company means the fund should not be subject to state or federal income tax on amounts distributed. The distributions generally consist of dividends and interest received by the fund, as well as capital gains realized by the fund on the sale of its investment securities.
 
Capital gains are increases in the values of capital assets, such as stock, from the time the assets are purchased.
 
The fund generally expects to pay distributions of substantially all of its income, if any, quarterly. Distributions from realized capital gains, if any, are paid annually, usually in December. It may make more frequent distributions if necessary to comply with Internal Revenue Code provisions.

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You will participate in fund distributions when they are declared, starting the next business day after your purchase is effective. For example, if you purchase shares on a day that a distribution is declared, you will not receive that distribution. If you redeem shares, you will receive any distribution declared on the day you redeem. If you redeem all shares, we will include any distributions received with your redemption proceeds.
Generally, participants in tax-deferred retirement plans reinvest all distributions. For investors investing through taxable accounts, we will reinvest distributions unless you elect to have dividends and/or capital gains sent to another American Century Investments account, to your bank electronically, or to your home address or to another person or address by check.

Taxes
Some of the tax consequences of owning shares of a fund will vary depending on whether you own them through a taxable or tax-deferred account. Distributions by a fund of dividend and interest income, capital gains and other income it has generated through its investment activities will generally be taxable to shareholders who hold shares in a taxable account. Tax consequences also may result when investors sell fund shares after the net asset value has increased or decreased.
Tax-Deferred Accounts
If you purchase fund shares through a tax-deferred account, such as an IRA or employer-sponsored retirement plan, income and capital gains distributions usually will not be subject to current taxation but will accumulate in your account under the plan on a tax-deferred basis. Likewise, moving from one fund to another fund within a plan or tax-deferred account generally will not cause you to be taxed. For information about the tax consequences of making purchases or withdrawals through a tax-deferred account, please consult your plan administrator, your summary plan description or a tax advisor.
Taxable Accounts
If you own fund shares through a taxable account, you may be taxed on your investments if the fund makes distributions or if you sell your fund shares.
Taxability of Distributions
Fund distributions may consist of income, such as dividends and interest earned by a fund from its investments, or capital gains generated by a fund from the sale of investment securities. Distributions of income are taxed as ordinary income, unless they are designated as qualified dividend income and you meet a minimum required holding period with respect to your shares of the fund, in which case distributions of income are taxed at the same rates as long-term capital gains.
 
Qualified dividend income is a dividend received by a fund from the stock of a domestic or qualifying foreign corporation, provided that the fund has held the stock for a required holding period.
 
The tax character of any distributions from capital gains is determined by how long the fund held the underlying security that was sold, not by how long you have been invested in the fund or whether you reinvest your distributions or take them in cash. Short-term (one year or less) capital gains are taxable as ordinary income. Gains on securities held for more than one year are taxed at the lower rates applicable to long-term capital gains.
If a fund’s distributions exceed current and accumulated earnings and profits, such excess will generally be considered a return of capital. A return of capital distribution is generally not subject to tax, but will reduce your cost basis in the fund and result in higher realized capital gains (or lower realized capital losses) upon the sale of fund shares.
For taxable accounts, American Century Investments or your financial intermediary will inform you of the tax character of fund distributions for each calendar year in an annual tax mailing.
If you meet specified income levels, you will also be subject to a 3.8% Medicare contribution tax which is imposed on net investment income, including interest, dividends and capital gains. Distributions also may be subject to state and local taxes. Because everyone’s tax situation is unique, you may want to consult your tax professional about federal, state and local tax consequences.
Taxes on Transactions
Your redemptions are subject to capital gains tax. Short-term capital gains are gains on fund shares you held for 12 months or less. Long-term capital gains are gains on fund shares you held for more than 12 months. If your shares decrease in value, their sale will result in a long-term or short-term capital loss. However, you should note that loss realized upon the sale of shares held for six months or less will be treated as a long-term capital loss to the extent of any distribution of long-term capital gain to you with respect to those shares. If a loss is realized on the redemption of fund shares, the reinvestment in additional fund shares within 30 days before or after the redemption may be subject to the wash sale rules of the Internal Revenue Code. This may result in a postponement of the recognition of such loss for federal income tax purposes.

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If you have not certified to us that your Social Security number or tax identification number is correct and that you are not subject to withholding, we are required to withhold and pay to the IRS the applicable federal withholding tax rate on taxable dividends, capital gains distributions and redemption proceeds.
Taxes on Creations and Redemptions of Creation Units
An Authorized Participant who exchanges securities for Creation Units generally will recognize a gain or a loss equal to the difference between the market value of the Creation Units at the time and the sum of the exchanger’s aggregate basis in the securities surrendered plus the amount of cash paid for such Creation Units. A person who redeems Creation Units will generally recognize a gain or loss equal to the difference between the exchanger’s basis in the Creation Units and the sum of the aggregate market value of any securities received plus the amount of any cash received for such Creation Units. The IRS, however, may assert that a loss realized upon an exchange of securities for Creation Units cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in economic position.
Any capital gain or loss realized upon the creation of Creation Units will generally be treated as long-term capital gain or loss if the securities exchanged for such Creation Units have been held for more than one year. Any capital gain or loss realized upon the redemption of Creation Units will generally be treated as long-term capital gain or loss if the shares comprising the Creation Units have been held for more than one year. Otherwise, such capital gains or losses will generally be treated as short-term capital gain or loss. Any loss upon a redemption of Creation Units held for six (6) months or less will be treated as a long-term capital loss to the extent of any amounts treated as distributions to the applicable Authorized Participant of long-term capital gain with respect to the Creation Units (including any amounts credited to the Authorized Participant as undistributed capital gains).
If a fund redeems Creation Units in cash, it may recognize more capital gains than it will if it redeems Creation Units in-kind.
Buying a Dividend
Purchasing fund shares in a taxable account shortly before a distribution is sometimes known as buying a dividend. In taxable accounts, you must pay income taxes on the distribution whether you reinvest the distribution or take it in cash. In addition, you will have to pay taxes on the distribution whether the value of your investment decreased, increased or remained the same after you bought the fund shares.
The risk in buying a dividend is that a fund’s portfolio may build up taxable income and gains throughout the period covered by a distribution, as income is earned and securities are sold at a profit. The fund distributes the income and gains to you, after subtracting any losses, even if you did not own the shares when the income was earned or the gains occurred.
If you buy a dividend, you incur the full tax liability of the distribution period, but you may not enjoy the full benefit of the income earned or the gains realized in the fund’s portfolio.
Additional Information
Premium/Discount Information
Information regarding how often the shares of the fund traded on NYSE Arca, Inc. at a price above (at a premium) or below (at a discount) the NAV of the fund can be found at americancenturyetfs.com.
Service, Distribution and Administrative Fees
Investment Company Act Rule 12b-1 permits investment companies that adopt a written plan to pay certain expenses associated with the distribution of their shares out of fund assets. The Board of Trustees has adopted a 12b-1 plan that allows the fund to pay annual fees not to exceed 0.25% to the distributor for distribution and individual shareholder services. However, the Board of Trustees has determined not to authorize payment of a 12b-1 plan fee at this time.
Because these fees may be used to pay for services that are not related to prospective sales of the fund, to the extent that a fee is authorized, the fund will continue to make payments under its plan even if it is closed to new investors. Because these fees are paid out of the fund’s assets on an ongoing basis, to the extent that a fee is authorized, over time these fees will increase the cost of your investment and may cost you more than paying other types of sales charges.
The advisor and its affiliates may make payments to intermediaries for various additional services, other expenses and/or the intermediaries’ distribution of the fund out of their profits or other available sources. Such payments may be made for one or more of the following: (1) distribution, which may include expenses incurred by intermediaries for their sales activities with respect to the fund, such as preparing, printing and distributing sales literature and advertising materials and compensating registered representatives or other employees of such financial intermediaries for their sales activities, as well as the opportunity for the fund to be made available by such intermediaries; (2) shareholder services, such as providing individual and custom investment advisory services to clients of the financial intermediaries; and (3) marketing and promotional services, including business planning assistance, educating personnel about the fund, and sponsorship of sales meetings, which may include covering costs of providing speakers, meals and other entertainment. The advisor may sponsor seminars and conferences designed to educate intermediaries about the fund and may cover the expenses associated with attendance at such meetings, including travel costs. These payments and activities are intended to provide

12



an incentive to intermediaries to sell the fund by educating them about the fund and helping defray the costs associated with offering the fund. These payments may create a conflict of interest by influencing the intermediary to recommend the fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information. The amount of any payments described by this paragraph is determined by the advisor, and all such amounts are paid out of the available assets of the advisor and its affiliates, and not by you or the fund. As a result, the total expense ratio of the fund will not be affected by any such payments.

Index Provider
The underlying index is maintained and calculated by STOXX® Ltd.

Disclaimers
STOXX® Limited, Deutsche Börse Group and their licensors, research partners or data providers have no relationship to American Century Investment Management, Inc., other than the licensing of the iSTOXX® American Century USA Quality Value Index and the related trademarks for use in connection with the fund.
iSTOXX® indices are tailored to a customer request or market requirement based on an individualized rule book which is not integrated into the STOXX® Global index family.
STOXX®, Deutsche Börse Group and their licensors, research partners or data providers do not:
sponsor, endorse, sell or promote the fund.
recommend that any person invest in the fund or any other securities.
have any responsibility or liability for or make any decisions about the timing, amount or pricing of fund shares.
have any responsibility or liability for the administration, management or marketing of the fund.
consider the needs of the fund or the owners of the fund in determining, composing or calculating the iSTOXX® American Century USA Quality Value Index or have any obligation to do so.
STOXX®, Deutsche Börse Group and their licensors, research partners or data providers give no warranty, and exclude any liability (whether in negligence or otherwise), in connection with the fund or their performance.
STOXX® does not assume any contractual relationship with the purchasers of the fund or any other third parties.
Specifically,
STOXX®, Deutsche Börse Group and their licensors, research partners or data providers do not give any warranty, express or implied, and exclude any liability about:
The results to be obtained by the fund, the owner of the fund or any other person in connection with the use of the iSTOXX® American Century USA Quality Value Index and the data included in the iSTOXX® American Century USA Quality Value Index;
The accuracy, timeliness, and completeness of the iSTOXX® American Century USA Quality Value Index and its data;
The merchantability and the fitness for a particular purpose or use of the iSTOXX® American Century USA Quality Value Index and its data;
The performance of the fund generally.
STOXX®, Deutsche Börse Group and their licensors, research partners or data providers give no warranty and exclude any liability, for any errors, omissions or interruptions in the iSTOXX® American Century USA Quality Value Index or its data;
Under no circumstances will STOXX®, Deutsche Börse Group or their licensors, research partners or data providers be liable (whether in negligence or otherwise) for any lost profits or indirect, punitive, special or consequential damages or losses, arising as a result of such errors, omissions or interruptions in the iSTOXX® American Century USA Quality Value Index or its data or generally in relation to the fund, even in circumstances where STOXX®, Deutsche Börse Group or their licensors, research partners or data providers are aware that such loss or damage may occur.
The licensing Agreement between American Century Investment Management, Inc. and STOXX® is solely for their benefit and not for the benefit of the owners of the fund or any other third parties.
Financial Highlights
There is no financial information for the fund because it is a new fund.
Notes

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Where to Find More Information
Annual and Semiannual Reports
Additional information about the fund’s investments will be available in the fund’s annual and semiannual reports to shareholders. In the fund’s annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the fund’s performance during its last fiscal year.
Statement of Additional Information (SAI)
The SAI contains a more detailed legal description of the fund’s operations, investment restrictions, policies and practices. The SAI is incorporated by reference into this prospectus. This means that it is legally part of this prospectus, even if you don’t request a copy.
You may obtain a free copy of the SAI, annual reports and semiannual reports, and you may ask questions about the fund or your accounts, online at americancenturyetfs.com, by contacting American Century Investments at the addresses or telephone numbers listed below or by contacting your financial intermediary.
The Securities and Exchange Commission (SEC)
Information about the fund (including the SAI) can be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C., and information on the operation of the Public Reference Room may be obtained by calling the SEC at 1-202-551-8090. Reports and other information about the fund are available on the EDGAR database on the SEC’s website at sec.gov, and copies of this information may be obtained, after paying a duplicating fee, by electronic request at the following email address: publicinfo@sec.gov, or by writing the SEC’s Public Reference Section, Washington, D.C. 20549-1520.

This prospectus shall not constitute an offer to sell securities of the fund in any state, territory, or other jurisdiction where the fund’s shares have not been registered or qualified for sale, unless such registration or qualification is not required, or under any circumstances in which such offer or solicitation would be unlawful.





American Century Investments
americancenturyetfs.com
P.O. Box 419385
Kansas City, Missouri 64141-6385
1-833-ACI-ETFS

Investment Company Act File No. 811-23305
CL-PRS-93573 1801






The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

[January 9, 2018]

American Century Investments
Prospectus

 
Ticker:
Exchange:
American Century Diversified Corporate Bond ETF
KORP
NYSE Arca, Inc.

















The Securities and Exchange Commission has
not approved or disapproved these securities or
passed upon the adequacy of this prospectus. Any
representation to the contrary is a criminal offense.
acietfslockupblacka01.jpg




Table of Contents
Fund Summary
2

Investment Objective
2

Fees and Expenses
2

Principal Investment Strategies
2

Principal Risks
2

Fund Performance
3

Portfolio Management
4

Purchase and Sale of Fund Shares
4

Tax Information
4

Payments to Broker-Dealers and Other Financial Intermediaries
4

Objectives, Strategies and Risks
5

Management
7

Investing in the Fund
9

Share Price and Distributions
10

Taxes
11

Additional Information
13

Financial Highlights
13





















©2018 American Century Proprietary Holdings, Inc. All rights reserved.




Fund Summary
Investment Objective
The fund seeks to provide current income.
Fees and Expenses
The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. You may also incur usual and customary brokerage commissions when buying or selling shares of the fund, which are not reflected in the example that follows.
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fee
0.45%
Other Expenses1
0.00%
Total Annual Fund Operating Expenses
0.45%
1Other expenses are based on estimated amounts for the current fiscal year.
Example
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 year
3 years
$46
$145
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
Under normal market conditions, the portfolio managers will invest at least 80% of the fund’s net assets, plus any borrowings for investment purposes, in corporate debt securities and corporate debt investments. Corporate debt investments are derivatives whose reference securities are corporate debt securities.
The fund invests primarily in U.S. dollar denominated corporate debt securities issued by U.S. and foreign entities, but may also invest in securities issued by supranational entities. Although the fund invests primarily in investment-grade debt securities, up to 35% of the fund’s net assets may be invested in high-yield securities (also referred to as “junk bonds”).
The fund also may invest in derivative instruments such as futures contracts, and swap agreements (including, but not limited to, interest rate swaps and credit default swap indexes). The fund may use derivative instruments to earn income, enhance returns, increase liquidity, manage target duration, gain exposure to certain instruments or markets, and/or hedge its exposure to particular investments.
Under normal market conditions, the weighted average duration of the fund’s portfolio is expected to be between three and seven years.
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
Authorized Participant Concentration - Only an authorized participant may engage in creation or redemption transactions directly with the fund. The fund has 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.

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Cash Transactions - 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.
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.
Derivatives Risk - The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. 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.
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.
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.
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.
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.
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 Trading - 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.
Principal Loss - 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.

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Portfolio Management
Investment Advisor
American Century Investment Management, Inc.
Portfolio Managers
Kevin Akioka, CFA, Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments for American Century since joining the advisor in 2010.
Jeffrey L. Houston, CFA, Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments since joining the advisor in 1990.
Gavin Fleischman, Vice President and Portfolio Manager, has served on teams managing fixed-income investments for American Century since joining the advisor in 2008.
Le Tran, Portfolio Manager, has served on teams managing fixed-income investments for American Century since joining the advisor in 2004.
Purchase and Sale of Fund Shares
The fund is an ETF. Fund shares may only be purchased and sold on a national securities exchange through a broker-dealer. The price of fund shares is based on market price, and 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). The fund issues and redeems shares that have been aggregated into blocks of 50,000 shares or multiples thereof (Creation Units) to authorized participants who have entered into agreements with the fund’s distributor. The fund will generally issue and redeem Creation Units in return for a basket of cash and/or securities that the fund specifies each day.
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.


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Objectives, Strategies and Risks
What are the fund’s investment objectives?
The fund seeks to provide current income.
The fund’s investment objective is a nonfundamental investment policy and may be changed by the Board of Trustees without approval by shareholders upon 60 days’ prior notice to shareholders.
What are the fund’s principal investment strategies?
Under normal market conditions, the portfolio managers will invest at least 80% of the fund’s net assets, plus any borrowings for investment purposes, in corporate debt securities and corporate debt investments. Corporate debt investments are derivatives whose reference securities are corporate debt securities.
Debt securities represent the obligation of the issuer to repay a loan of money to it, and generally pay interest to the holder. Debt securities include bonds, notes and debentures.
The fund invests primarily in U.S. dollar denominated corporate bonds and other corporate debt securities issued by U.S. and foreign entities, but may also invest in securities issued by supranational entities. Although the fund invests primarily in investment-grade securities, up to 35% of the fund’s net assets may be invested in high-yield corporate debt securities and other high-yield debt securities.
A high-yield security (also referred to as a “junk bond”) is one that has been rated below the four highest categories used by a nationally recognized statistical rating organization, or determined by the investment advisor to be of similar quality. Details of the fund’s credit quality standards are described in the statement of additional information.
The fund also may invest in derivative instruments such as futures contracts and swap agreements (including, but not limited to, interest rate swaps and credit default swap indexes). The fund may use derivative instruments to earn income, enhance returns, increase liquidity, manage target duration, gain exposure to certain instruments or markets, and/or hedge its exposure to particular investments.
Under normal market conditions, the weighted average duration of the fund’s portfolio is expected to be between three and seven years.
Duration, which is an indication of the relative sensitivity of a security’s market value to changes in interest rates, is based upon the aggregate of the present value of all principal and interest payments to be received, discounted at the current market rate of interest and expressed in years. The longer the weighted average duration of the fund’s portfolio, the more sensitive its market value is to interest rate fluctuations. For example, if the weighted average duration of the fund’s portfolio is two years, a 2% change in the value of the fund’s portfolio would be expected for every 1% change in interest rates.
For temporary defensive purposes, the fund may invest without limit in securities that are inconsistent with the fund’s principal investment strategies, such as cash, cash equivalents, money market instruments or other high quality short-term investments. To the extent the fund assumes a defensive position, it may not achieve its investment objective.
The fund is an actively managed ETF that does not seek to replicate the performance of a specified index. The portfolio managers decide which debt securities to buy and sell by, among other things:
identifying debt securities that satisfy the fund’s credit quality standards
determining which debt securities help the fund meet its maturity requirements
assessing current and anticipated interest rates
evaluating current economic conditions and the risk of inflation
evaluating special features of the debt securities that may make them more or less attractive to alternatives.
A description of the policies and procedures with respect to the disclosure of the fund’s portfolio securities is available in the statement of additional information. Portfolio holdings information can be viewed online at americancenturyetfs.com.
What are the principal risks of investing in the fund?
Authorized Participant Concentration - Only an authorized participant may engage in creation or redemption transactions directly with the fund. The fund has 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 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.

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Cash Transactions - ETFs generally are able to make in-kind redemptions and avoid being taxed on gain on the distributed portfolio securities at the fund level. However, because the fund may effect redemptions in cash, rather than in-kind, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. If the fund recognizes gain on these sales, this generally will cause the fund to recognize gain it might not otherwise have recognized, or to recognize such gain sooner than would otherwise be required if it were to distribute portfolio securities in-kind. The fund generally intends to distribute these gains to shareholders to avoid being taxed on this gain at the fund level and otherwise comply with the special tax rules that apply to it. This strategy may cause shareholders to be subject to tax on gains they would not otherwise be subject to, or at an earlier date than, if they had made an investment in a different ETF. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid and may involve considerable brokerage fees and taxes. These brokerage fees and taxes, which will be higher than if the fund sold and redeemed its shares principally in-kind, will be passed on to purchasers and redeemers of Creation Units in the form of creation and redemption transaction fees.
Credit Risk - Credit risk is the risk that 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. A high credit rating indicates a high degree of confidence by the rating organization that the issuer will be able to withstand adverse business, financial or economic conditions and make interest and principal payments on time. A lower credit rating indicates a greater risk of non-payment. Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes or adverse developments specific to the issuer. In addition, lower-rated securities may be unsecured or subordinated to other obligations of the issuer. These factors may be more likely to cause an issuer of low-quality bonds to default on its obligation to pay the interest and principal due under its securities. The fund’s credit quality restrictions apply at the time of purchase; the fund will not necessarily sell securities if they are downgraded by a rating agency.
Derivatives Risk - The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks, including liquidity, interest rate, market, and credit risk. They also involve the risk of mispricing or improper valuation, the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index, and the risk of default or bankruptcy of the other party to the instrument. Gains or losses involving some futures, options, and other derivatives may be substantial - in part because a relatively small price movement in these securities may result in an immediate and substantial gain or loss for the fund. 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.
Foreign Securities Risk - The fund may invest in the securities of foreign issuers, which are generally riskier than U.S. securities. In addition, investing in securities of issuers located in emerging market countries generally is riskier than investing in securities of issuers located in foreign developed countries. As a result, the fund may be subject to foreign and emerging market risk, meaning that political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), and natural disasters occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. In addition, foreign and emerging market securities can have reduced availability of public information, and the lack of uniform financial reporting and regulatory practices similar to those that apply to U.S. issuers. For these and other reasons, securities of foreign and emerging market issuers are often more volatile, less liquid and harder to value than those of U.S. issuers.
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.
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 degree to which interest rate changes affect the fund’s performance varies and is related to the weighted average maturity of the fund. For example, when interest rates rise, you can expect the share value of a long-term bond fund to fall more than that of a short-term bond fund. When rates fall, the opposite is true. 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.
Liquidity Risk - The chance that a fund will have difficulty selling its debt securities is called 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. Adverse publicity and investor perceptions, as well as new and proposed laws, also may have a greater negative impact on the market for lower-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. In addition, when the market for certain investments is illiquid, the fund may be unable to achieve its desired level of exposure to a certain sector. Illiquid securities may be difficult to value. 

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Market Risk - The value of the fund’s shares depends on the value of the bonds and other securities it owns. The value of the individual securities the fund owns will go up and down, sometimes rapidly or unpredictably, depending on the performance of the issuers that issued them, general market and economic conditions and investor confidence.
Market Trading - Although shares of the fund are listed for trading on one or more stock exchanges, there can be no assurance that an active trading market for such shares will develop or be maintained. There are no obligations of market makers to make a market in the fund’s shares or of an authorized participant to submit purchase or redemption orders for Creation Units. Decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying value of the fund’s portfolio securities and the fund’s market price. This reduced effectiveness could result in fund shares trading at a premium or discount to its NAV and also greater than normal intraday bid/ask spreads.
Shares of the fund may trade in the secondary market at times when the fund does not accept orders to purchase or redeem shares. At such times, shares may trade in the secondary market with more significant premiums or discounts than might be experienced at times when the fund accepts purchase and redemption orders. Secondary market trading in fund shares may be halted by a stock exchange because of market conditions or other reasons, and may be subject to trading halts caused by extraordinary market volatility pursuant to “circuit breaker” rules on the stock exchange or market. There can be no assurance that the requirements necessary to maintain the listing or trading of fund shares will continue to be met or will remain unchanged. In addition, during a “flash crash,” the market prices of the fund’s shares may decline suddenly and significantly. Such a decline may not reflect the performance of the portfolio securities held by the fund. Flash crashes may cause authorized participants and other market makers to limit or cease trading in the fund’s shares for temporary or longer periods. Shareholders could suffer significant losses to the extent that they sell fund shares at these temporarily low market prices.
Shares of the fund may trade at prices other than 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. While the creation/redemption feature is designed to make it likely that the fund’s shares normally will trade on stock exchanges at prices close to the fund’s next calculated NAV, market prices are not expected to correlate exactly with the fund’s NAV due to timing reasons as well as market supply and demand factors. In addition, disruptions to creations and redemptions or extreme market volatility may result in trading prices for shares of the fund that differ significantly from its NAV. The portfolio managers cannot predict whether shares will trade above (premium), below (discount) or at NAV.
When buying or selling shares of the fund through a broker, you will likely incur a brokerage commission or other charges determined by your broker. In addition, you may incur the cost of the “spread,” that is, any difference between the bid price and the ask price. The spread varies over time for shares of the fund based on the fund’s trading volume and market liquidity, and is generally lower if the fund has a lot of trading volume and market liquidity, and higher if the fund has little trading volume and market liquidity. During times of market stress, spreads may widen causing investors to pay more.
Principal Loss - 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.

Management
Who manages the fund?
The Board of Trustees, investment advisor and fund management team play key roles in the management of the fund.
The Board of Trustees
The Board of Trustees is responsible for overseeing the advisor’s management and operations of the fund pursuant to the management agreement. In performing their duties, Board members receive detailed information about the fund and its advisor regularly throughout the year, and meet at least quarterly with management of the advisor to review reports about fund operations. The trustees’ role is to provide oversight and not to provide day-to-day management. The majority of the trustees are independent of the fund’s advisor. They are not employees, directors or officers of, and have no financial interest in, the advisor or any of its affiliated companies (other than as shareholders of American Century Investments funds), and they do not have any other affiliations, positions or relationships that would cause them to be considered “interested persons” under the Investment Company Act of 1940 (Investment Company Act).
The Investment Advisor
The fund’s investment advisor is American Century Investment Management, Inc. (the advisor). The advisor has been managing investment companies since 1958 and is headquartered at 4500 Main Street, Kansas City, Missouri 64111.
The advisor is responsible for managing the investment portfolio of the fund and directing the purchase and sale of its investment securities. The advisor also arranges for transfer agency, custody and all other services necessary for the fund to operate.
For the services it provides to the fund, the advisor receives a unified management fee based on a percentage of the daily net assets of the fund at the annual rate of 0.45%. The amount of the fee is calculated daily and paid monthly in arrears. The advisor pays all

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expenses of managing and operating the fund, other than the management fee payable to the advisor, brokerage and other transaction fees and expenses relating to the acquisition and disposition of portfolio securities, acquired fund fees and expenses, interest, taxes, litigation expenses, extraordinary expenses, and expenses incurred in connection with the provision of shareholder and distribution services under a plan adopted pursuant to Rule 12b-1 under the Investment Company Act (if any). The advisor may pay unaffiliated third parties who provide recordkeeping and administrative services that would otherwise be performed by an affiliate of the advisor.
A discussion regarding the basis for the Board of Trustees’ approval of the fund’s investment advisory agreement with the advisor will be available in the fund’s semiannual report to shareholders for the period ended February 28, 2018.
The Fund Management Team
The advisor uses teams of portfolio managers and analysts, organized by broad investment categories such as money markets, corporate bonds, government bonds and municipal bonds, in its management of fixed-income funds. Designated portfolio managers serve on the firm’s Global Macro Strategy Team, which is responsible for periodically adjusting the fund’s strategic investment parameters based on economic and market conditions. The fund’s portfolio managers are responsible for security selection and portfolio construction for the fund within these strategic parameters, as well as compliance with stated investment objectives and cash flow monitoring. Other members of the investment team provide research and analytical support but generally do not make day-to-day investment decisions for the fund.
The individuals listed below are jointly and primarily responsible for the day-to-day management of the fund described in this prospectus. 
Kevin Akioka (Global Macro Strategy Team Representative)
Mr. Akioka, Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments for American Century since joining the advisor in 2010. He has a bachelor’s degree in economics and psychology from the University of California, Irvine and an MBA from New York University. He is a CFA charterholder. 
Jeffrey L. Houston 
Mr. Houston, Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments for American Century since joining the advisor in 1990. He has a bachelor’s degree in history and political science from the University of Delaware and a master’s degree of public administration from Syracuse University. He is a CFA charterholder. 
Gavin Fleischman
Mr. Fleischman, Vice President and Portfolio Manager, has served on teams managing fixed-income investments for American Century since joining the advisor in 2008 as a corporate analyst. He was promoted to portfolio manager in 2015. He has a bachelor’s degree in history from Lafayette College and an MBA in finance from Fordham University.
Le Tran
Mr. Tran, Portfolio Manager, has served on teams managing fixed-income investments for American Century since joining the advisor in 2004.  He has a bachelor’s degree in business administration from San Francisco State University.
The statement of additional information provides additional information about the accounts managed by the portfolio managers, the structure of their compensation, and their ownership of fund securities.
Fundamental Investment Policies
Shareholders must approve any change to the fundamental investment policies contained in the statement of additional information, as well as any change to the investment objective of the fund. The Board of Trustees and/or the advisor may change any other policies or investment strategies described in this prospectus or otherwise used in the operation of the fund at any time, subject to applicable notice provisions.


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Investing in the Fund
Buying and Selling Shares
Shares of the fund may be acquired or redeemed directly from the fund only in Creation Units or multiples thereof, as discussed below. Only an authorized participant may engage in creation and redemption transactions directly with the fund. Once created, shares of the fund generally trade in the secondary market in amounts less than a Creation Unit.
Shares of the fund are listed on a national securities exchange for trading during the trading day. Shares can be bought and sold throughout the trading day like shares of other publicly traded companies. American Century ETF Trust (the trust) does not impose any minimum investment for shares of the fund purchased on an exchange. Shares of the fund trade under the following ticker symbol: KORP.
Buying or selling fund shares on an exchange involves two types of costs that may apply to all securities transactions. When buying or selling shares of the fund through a broker, you will likely incur a brokerage commission or other charges determined by your broker. The commission is frequently a fixed amount and may be a significant proportional cost for investors seeking to buy or sell small amounts of shares. In addition, you may incur the cost of the “spread,” that is, any difference between the bid price and the ask price. The spread varies over time for shares of the fund based on the fund’s trading volume and market liquidity, and is generally lower if the fund has a lot of trading volume and market liquidity, and higher if the fund has little trading volume and market liquidity.
The fund’s primary listing exchange is NYSE Arca, Inc., which is open for trading Monday through Friday and is closed on weekends and the following holidays: New Year’s Day, Martin Luther King, Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day.
Book Entry
Shares of the fund are held in book-entry form, which means that no share certificates are issued. The Depository Trust Company (DTC) or its nominee is the record owner of all outstanding shares of the fund and is recognized as the owner of all shares for all purposes.
Investors owning shares of the fund are beneficial owners as shown on the records of DTC or its participants. DTC serves as the securities depository for shares of the fund. DTC participants include securities brokers and dealers, banks, trust companies, clearing corporations and other institutions that directly or indirectly maintain a custodial relationship with DTC. As a beneficial owner of shares, you are not entitled to receive physical delivery of stock certificates or to have shares registered in your name, and you are not considered a registered owner of shares. Therefore, to exercise any right as an owner of shares, you must rely upon the procedures of DTC and its participants. These procedures are the same as those that apply to any other securities that you hold in book-entry or “street name” form.
Frequent Trading Practices
The Board of Trustees has not adopted a policy of monitoring for frequent purchases and redemptions of fund shares (frequent trading). The Board of Trustees believes that a frequent trading policy is unnecessary because fund shares are listed for trading on a national securities exchange. Therefore, it is unlikely that a shareholder could take advantage of a potential arbitrage opportunity presented by a lag between a change in the value of the fund’s portfolio securities after the close of the primary markets for the fund’s portfolio securities and the reflection of that change in the fund’s NAV (market timing), because the fund generally sells and redeems its shares directly through transactions that are in-kind and/or for cash, subject to the conditions described below under Creations and Redemptions. The Board of Trustees has not adopted a policy of monitoring for frequent trading activity in fund shares because fund shares are listed for trading on a national securities exchange.
Investments by Other Investment Companies
Section 12(d)(1) of the Investment Company Act restricts investments by investment companies in the securities of other investment companies. Registered investment companies are permitted to invest in the fund beyond the limits set forth in Section 12(d)(1), subject to certain terms and conditions set forth in SEC rules or in an SEC exemptive order issued to the trust. In order for a registered investment company to invest in shares of the fund beyond the limitations of Section 12(d)(1) pursuant to the exemptive relief obtained by the trust, the registered investment company must enter into an agreement with the trust.
Creations and Redemptions
Prior to trading in the secondary market, shares of the fund are “created” at NAV by market makers, large investors and institutions only in block-size Creation Units of 50,000 shares or multiples thereof. All orders to purchase Creation Units must be placed by or through an authorized participant that has entered into an authorized participant agreement (AP Agreement) with Foreside Fund Services, LLC (the distributor). Only an authorized participant may create or redeem Creation Units directly with the fund.
A creation transaction, which is subject to acceptance by the trust, generally takes place when an authorized participant deposits into the fund a designated portfolio of securities and/or cash (which may include cash in lieu of certain securities) in exchange for a specified number of Creation Units. With respect to the fund, these deposits are generally in cash. Similarly, shares can be redeemed only in Creation Units, generally for a designated portfolio of securities and/or cash (which may include cash in lieu of certain

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securities). With respect to the fund, redemptions are generally on an in-kind basis, but the fund reserves the right to meet redemptions in cash. Except when aggregated in Creation Units, shares are not redeemable by the fund.
The prices at which creations and redemptions occur are based on the next calculation of NAV after a creation or redemption order is received in an acceptable form under the AP Agreement. The portfolio of securities required for purchase of a Creation Unit is generally the same as the portfolio of securities the fund will deliver upon redemption of fund shares, except under certain circumstances. The designated portfolio of securities in connection with a purchase or redemption of a Creation Unit generally will correspond pro rata, except under certain circumstances, to the securities held by the fund. As a result of any system failure or other interruption, creation or redemption orders either may not be executed according to the fund’s instructions or may not be executed at all, or the fund may not be able to place or change such orders.
Creations and redemptions must be made through a firm that is either a broker-dealer or other participant in the Continuous Net Settlement System of the National Securities Clearing Corporation or a DTC participant and, in either case, has executed an AP Agreement with the distributor. Information about the procedures regarding creations and redemptions of Creation Units (including the cut-off times for receipt of creation and redemption orders) is included in the fund’s statement of additional information (SAI).
Because new shares may be created and issued on an ongoing basis, at any point during the life of the fund a “distribution,” as such term is used in the Securities Act of 1933 (Securities Act), may be occurring. Broker-dealers and other persons are cautioned that some activities on their part may, depending on the circumstances, result in their being deemed participants in a distribution in a manner that could render them statutory underwriters and subject to the prospectus delivery and liability provisions of the Securities Act. Any determination of whether one is an underwriter must take into account all the relevant facts and circumstances of each particular case.
Broker-dealers should also note that dealers who are not “underwriters” but are participating in a distribution (as contrasted to ordinary secondary transactions), and thus dealing with shares that are part of an “unsold allotment” within the meaning of Section 4(a)(3)(C) of the Securities Act, would be unable to take advantage of the prospectus delivery exemption provided by Section 4(a)(3) of the Securities Act. For delivery of prospectuses to exchange members, the prospectus delivery mechanism of Rule 153 under the Securities Act is available only with respect to transactions on a national securities exchange.

Share Price and Distributions
Share Price
The trading prices of the fund’s shares in the secondary market generally differ from the fund’s daily NAV and are affected by market forces such as supply and demand, economic conditions and other factors. Information regarding the intraday value of shares of the fund, also known as the “indicative optimized portfolio value” (IOPV), is disseminated every 15 seconds throughout the trading day by the national securities exchange on which the fund’s shares are listed or by market data vendors or other information providers. The IOPV is based on the current market value of the securities and/or cash contained in the portfolio at the beginning of the trading day. The IOPV does not necessarily reflect the best possible valuation of the current portfolio of securities held by the fund, and may not be calculated in the same manner as the NAV. Therefore, the IOPV should not be viewed as a “real-time” update of the fund’s NAV, which is computed only once a day as described below. The IOPV is generally determined by using both current market quotations and/or price quotations obtained from broker-dealers that may trade in the portfolio securities held by the fund. The quotations of certain fund holdings may not be updated during U.S. trading hours if such holdings do not trade in the United States. The fund, the advisor and their related entities are not involved in, or responsible for, the calculation or dissemination of the IOPV and make no representation or warranty as to its accuracy.
Calculation of NAV
American Century Investments will price the fund shares purchased or redeemed by authorized participants based on the net asset value (NAV) next determined after an order is received in good order by the fund’s transfer agent. We determine the NAV of the fund as of the close of regular trading (usually 4 p.m. Eastern time) on the New York Stock Exchange (NYSE) on each day the NYSE is open. On days when the NYSE is closed (including certain U.S. national holidays), we do not calculate the NAV.
 
The net asset value, or NAV, of the fund is the current value of the fund’s assets, minus any liabilities, divided by the number of shares of the fund outstanding.
 
Readily available market quotations for fixed-income securities shall generally be received from independent pricing services that have been approved by the Board. It is anticipated that such pricing services will generally provide evaluated prices based on accepted industry conventions. Evaluated prices are commonly derived through utilization of market models. Such models take into consideration various market factors and security characteristics. These include, but are not limited to, the following: trade data, quotations from broker-dealers and active market makers, relevant yield curve and spread data, related sector levels, creditworthiness, trade data or market information on comparable securities and other relevant security specific information. Debt obligations with 60 days or less remaining until maturity may be valued at amortized cost.

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If the fund determines that the market price for a portfolio security is not readily available or that the valuation methods mentioned above do not reflect the security’s fair value, such security is valued as determined in good faith by the fund’s board or its designee, in accordance with procedures adopted by the fund’s board. Circumstances that may cause the fund to use alternate procedures to value a security include, but are not limited to:
if, after the close of the foreign exchange on which a portfolio security is principally traded, but before the close of the NYSE, an event occurs that may materially affect the value of the security;
a debt security has been declared in default; or
trading in a security has been halted during the trading day.
If such circumstances occur, the fund will fair value the security if the fair valuation would materially impact the fund’s NAV. While fair value determinations involve judgments that are inherently subjective, these determinations are made in good faith in accordance with procedures adopted by the fund’s board.
The effect of using fair value determinations is that the fund’s NAV will be based, to some degree, on security valuations that the board or its designee believes are fair rather than being solely determined by the market.
With respect to any portion of the fund’s assets that are invested in one or more open-end management investment companies that are registered with the SEC (known as registered investment companies), the fund’s NAV will be calculated based upon the NAVs of such registered investment companies. These registered investment companies are required by law to explain the circumstances under which they will use fair value pricing and the effects of using fair value pricing in their prospectuses.
Trading of securities in foreign markets may not take place every day the NYSE is open. Also, trading in some foreign markets and on some electronic trading networks may take place on weekends or holidays when the fund’s NAV is not calculated. So, the value of the fund’s portfolio may be affected on days when you will not be able to purchase or sell fund shares.
Distributions
Federal tax laws require the fund to make distributions to its shareholders in order to qualify as a regulated investment company. Qualification as a regulated investment company means the fund should not be subject to state or federal income tax on amounts distributed. The distributions generally consist of dividends and interest received by the fund, as well as capital gains realized by the fund on the sale of its investment securities.
 
Capital gains are increases in the values of capital assets, such as stock, from the time the assets are purchased.
 
The fund generally expects to declare distributions from net income, if any, monthly. The fund generally pays distributions from realized capital gains, if any, once a year, usually in December. It may make more frequent distributions if necessary to comply with Internal Revenue Code provisions.
You will participate in fund distributions when they are declared, starting the next business day after your purchase is effective. For example, if you purchase shares on a day that a distribution is declared, you will not receive that distribution. If you redeem shares, you will receive any distribution declared on the day you redeem. If you redeem all shares, we will include any distributions received with your redemption proceeds.
Generally, participants in tax-deferred retirement plans reinvest all distributions. For investors investing through taxable accounts, we will reinvest distributions unless you elect to have dividends and/or capital gains sent to another American Century Investments account, to your bank electronically, or to your home address or to another person or address by check.
Taxes
Some of the tax consequences of owning shares of the fund will vary depending on whether you own them through a taxable or tax-deferred account. Distributions by the fund of dividend and interest income, capital gains and other income it has generated through its investment activities will generally be taxable to shareholders who hold shares in a taxable account. Tax consequences also may result when investors sell fund shares after the net asset value has increased or decreased.
Tax-Deferred Accounts
If you purchase fund shares through a tax-deferred account, such as an IRA or employer-sponsored retirement plan, income and capital gains distributions usually will not be subject to current taxation but will accumulate in your account under the plan on a tax-deferred basis. Likewise, moving from one fund to another fund within a plan or tax-deferred account generally will not cause you to be taxed. For information about the tax consequences of making purchases or withdrawals through a tax-deferred account, please consult your plan administrator, your summary plan description or a tax advisor.
Taxable Accounts
If you own fund shares through a taxable account, you may be taxed on your investments if the fund makes distributions or if you sell your fund shares.

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Taxability of Distributions
Fund distributions may consist of income, such as dividends and interest earned by the fund from its investments, or capital gains generated by the fund from the sale of investment securities. Distributions of income are taxed as ordinary income, unless they are designated as qualified dividend income and you meet a minimum required holding period with respect to your shares of the fund, in which case distributions of income are taxed at the same rates as long-term capital gains.
 
Qualified dividend income is a dividend received by a fund from the stock of a domestic or qualifying foreign corporation, provided that the fund has held the stock for a required holding period.
 
The tax character of any distributions from capital gains is determined by how long the fund held the underlying security that was sold, not by how long you have been invested in the fund or whether you reinvest your distributions or take them in cash. Short-term (one year or less) capital gains are taxable as ordinary income. Gains on securities held for more than one year are taxed at the lower rates applicable to long-term capital gains.
If a fund’s distributions exceed current and accumulated earnings and profits, such excess will generally be considered a return of capital. A return of capital distribution is generally not subject to tax, but will reduce your cost basis in the fund and result in higher realized capital gains (or lower realized capital losses) upon the sale of fund shares.
For taxable accounts, American Century Investments or your financial intermediary will inform you of the tax character of fund distributions for each calendar year in an annual tax mailing.
If you meet specified income levels, you will also be subject to a 3.8% Medicare contribution tax which is imposed on net investment income, including interest, dividends and capital gains. Distributions also may be subject to state and local taxes. Because everyone’s tax situation is unique, you may want to consult your tax professional about federal, state and local tax consequences.
Taxes on Transactions
Your redemptions are subject to capital gains tax. Short-term capital gains are gains on fund shares you held for 12 months or less. Long-term capital gains are gains on fund shares you held for more than 12 months. If your shares decrease in value, their sale will result in a long-term or short-term capital loss. However, you should note that loss realized upon the sale of shares held for six months or less will be treated as a long-term capital loss to the extent of any distribution of long-term capital gain to you with respect to those shares. If a loss is realized on the redemption of fund shares, the reinvestment in additional fund shares within 30 days before or after the redemption may be subject to the wash sale rules of the Internal Revenue Code. This may result in a postponement of the recognition of such loss for federal income tax purposes.
If you have not certified to us that your Social Security number or tax identification number is correct and that you are not subject to withholding, we are required to withhold and pay to the IRS the applicable federal withholding tax rate on taxable dividends, capital gains distributions and redemption proceeds.
Taxes on Creations and Redemptions of Creation Units
An Authorized Participant who exchanges securities for Creation Units generally will recognize a gain or a loss equal to the difference between the market value of the Creation Units at the time and the sum of the exchanger’s aggregate basis in the securities surrendered plus the amount of cash paid for such Creation Units. A person who redeems Creation Units will generally recognize a gain or loss equal to the difference between the exchanger’s basis in the Creation Units and the sum of the aggregate market value of any securities received plus the amount of any cash received for such Creation Units. The IRS, however, may assert that a loss realized upon an exchange of securities for Creation Units cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in economic position.
Any capital gain or loss realized upon the creation of Creation Units will generally be treated as long-term capital gain or loss if the securities exchanged for such Creation Units have been held for more than one year. Any capital gain or loss realized upon the redemption of Creation Units will generally be treated as long-term capital gain or loss if the shares comprising the Creation Units have been held for more than one year. Otherwise, such capital gains or losses will generally be treated as short-term capital gain or loss. Any loss upon a redemption of Creation Units held for six (6) months or less will be treated as a long-term capital loss to the extent of any amounts treated as distributions to the applicable Authorized Participant of long-term capital gain with respect to the Creation Units (including any amounts credited to the Authorized Participant as undistributed capital gains).
If a fund redeems Creation Units in cash, it may recognize more capital gains than it will if it redeems Creation Units in-kind.
Buying a Dividend
Purchasing fund shares in a taxable account shortly before a distribution is sometimes known as buying a dividend. In taxable accounts, you must pay income taxes on the distribution whether you reinvest the distribution or take it in cash. In addition, you will have to pay taxes on the distribution whether the value of your investment decreased, increased or remained the same after you bought the fund shares.

12



The risk in buying a dividend is that a fund’s portfolio may build up taxable income and gains throughout the period covered by a distribution, as income is earned and securities are sold at a profit. The fund distributes the income and gains to you, after subtracting any losses, even if you did not own the shares when the income was earned or the gains occurred.
If you buy a dividend, you incur the full tax liability of the distribution period, but you may not enjoy the full benefit of the income earned or the gains realized in the fund’s portfolio.
Additional Information
Premium/Discount Information
Information regarding how often the shares of the fund traded on NYSE Arca, Inc. at a price above (at a premium) or below (at a discount) the NAV of the fund can be found at americancenturyetfs.com.
Service, Distribution and Administrative Fees
Investment Company Act Rule 12b-1 permits investment companies that adopt a written plan to pay certain expenses associated with the distribution of their shares out of fund assets. The Board of Trustees has adopted a 12b-1 plan that allows the fund to pay annual fees not to exceed 0.25% to the distributor for distribution and individual shareholder services. However, the Board of Trustees has determined not to authorize payment of a 12b-1 plan fee at this time.
Because these fees may be used to pay for services that are not related to prospective sales of the fund, to the extent that a fee is authorized, the fund will continue to make payments under its plan even if it is closed to new investors. Because these fees are paid out of the fund’s assets on an ongoing basis, to the extent that a fee is authorized, over time these fees will increase the cost of your investment and may cost you more than paying other types of sales charges.
The advisor or its affiliates may make payments to intermediaries for various additional services, other expenses and/or the intermediaries’ distribution of the fund out of their profits or other available sources. Such payments may be made for one or more of the following: (1) distribution, which may include expenses incurred by intermediaries for their sales activities with respect to the fund, such as preparing, printing and distributing sales literature and advertising materials and compensating registered representatives or other employees of such financial intermediaries for their sales activities, as well as the opportunity for the fund to be made available by such intermediaries; (2) shareholder services, such as providing individual and custom investment advisory services to clients of the financial intermediaries; and (3) marketing and promotional services, including business planning assistance, educating personnel about the fund, and sponsorship of sales meetings, which may include covering costs of providing speakers, meals and other entertainment. The advisor may sponsor seminars and conferences designed to educate intermediaries about the fund and may cover the expenses associated with attendance at such meetings, including travel costs. These payments and activities are intended to provide an incentive to intermediaries to sell the fund by educating them about the fund and helping defray the costs associated with offering the fund. These payments may create a conflict of interest by influencing the intermediary to recommend the fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information. The amount of any payments described by this paragraph is determined by the advisor or the distributor, and all such amounts are paid out of the available assets of the advisor or its affiliates, and not by you or the fund. As a result, the total expense ratio of the fund will not be affected by any such payments.

Financial Highlights
There is no financial information for the fund because it is a new fund.


13



Notes





Where to Find More Information
Annual and Semiannual Reports
Additional information about the fund’s investments will be available in the fund’s annual and semiannual reports to shareholders. In the fund’s annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the fund’s performance during its last fiscal year.
Statement of Additional Information (SAI)
The SAI contains a more detailed legal description of the fund’s operations, investment restrictions, policies and practices. The SAI is incorporated by reference into this prospectus. This means that it is legally part of this prospectus, even if you don’t request a copy.
You may obtain a free copy of the SAI, annual reports and semiannual reports, and you may ask questions about the fund or your accounts, online at americancenturyetfs.com, by contacting American Century Investments at the addresses or telephone numbers listed below or by contacting your financial intermediary.
The Securities and Exchange Commission (SEC)
Information about the fund (including the SAI) can be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C., and information on the operation of the Public Reference Room may be obtained by calling the SEC at 1-202-551-8090. Reports and other information about the fund are available on the EDGAR database on the SEC’s website at sec.gov, and copies of this information may be obtained, after paying a duplicating fee, by electronic request at the following email address: publicinfo@sec.gov, or by writing the SEC’s Public Reference Section, Washington, D.C. 20549-1520.

This prospectus shall not constitute an offer to sell securities of the fund in any state, territory, or other jurisdiction where the fund’s shares have not been registered or qualified for sale, unless such registration or qualification is not required, or under any circumstances in which such offer or solicitation would be unlawful.






American Century Investments
americancenturyetfs.com
Financial Professionals
P.O. Box 419385
Kansas City, Missouri 64141-6385
1-833-ACI-ETFS

Investment Company Act File No. 811-23305
CL-PRS-93575 1801




The information in this statement of additional information is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This statement of additional information is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

[January 9, 2018]

American Century Investments
Statement of Additional Information

American Century ETF Trust
 
Ticker:
Exchange:
American Century STOXX® U.S. Quality Value ETF
VALQ
NYSE Arca, Inc.
American Century Diversified Corporate Bond ETF
KORP
NYSE Arca, Inc.















This statement of additional information adds to the discussion in the funds’ prospectuses dated [January 9, 2018], but is not a prospectus. The statement of additional information should be read in conjunction with the funds’ current prospectuses. If you would like a copy of a prospectus, please contact us at one of the addresses or telephone numbers listed on the back cover or visit American Century Investments’ website at americancenturyetfs.com.
acietfslockupblacka01.jpg

©2018 American Century Proprietary Holdings, Inc. All rights reserved.




Table of Contents
The Funds’ History
2

 
Exchange Listing and Trading
2

 
Fund Investment Guidelines
3

 
Fund Investments and Risks
4

 
Investment Strategies and Risks
4

 
Investment Policies
24

 
Temporary Defensive Measures
26

 
Portfolio Turnover
26

 
Disclosure of Portfolio Holdings
26

 
Management
27

 
The Board of Trustees
27

 
Officers
30

 
Code of Ethics
31

 
Proxy Voting Policies
31

 
The Funds’ Principal Shareholders
31

 
Creation and Redemption of Creation Units
32

 
Service Providers
38

 
Investment Advisor
38

 
Portfolio Managers
39

 
Transfer Agent
41

 
Administrator
42

 
Sub-Administrator
42

 
Distributor
42

 
Custodian Bank
43

 
Independent Registered Public Accounting Firm
43

 
Brokerage Allocation
43

 
Information About Fund Shares
44

 
Valuation of a Fund’s Securities
44

 
Taxes
45

 
Federal Income Taxes
45

 
State and Local Taxes
47

 
Financial Statements
47

 
 
 
Appendix A - Explanation of Fixed-Income Securities Ratings
A-1
Appendix B - Proxy Voting Policies
B-1






The Funds’ History
American Century ETF Trust is a registered open-end management investment company that was organized as a Delaware statutory trust on June 27, 2017. Throughout this statement of additional information (SAI) we refer to American Century ETF Trust as the trust.
Each fund described in this SAI (each, a “fund” and together, the “funds”) is a separate series of the trust. Each fund has its own investment objective, strategies, assets, and tax identification and stock registration numbers.
The funds offer and issue shares at their net asset value per share (NAV) only in aggregations of a specified number of shares (a “Creation Unit”), generally in exchange for a designated portfolio of securities (including any portion of such securities for which cash may be substituted) (Deposit Securities), together with the deposit of a specified cash payment (Cash Component) (other than the American Century Diversified Corporate Bond ETF, which generally offers Creation Units of its shares solely for cash). Shares of each fund are listed for trading on NYSE Arca, Inc. (Listing Exchange or NYSE Arca), a national securities exchange. Shares of each fund are traded in the secondary market and elsewhere at market prices that may be at, above or below the fund’s NAV. Shares of each fund are redeemable only in Creation Units, generally in exchange for portfolio securities and a Cash Component. Creation Units typically are a specified number of shares, generally 25,000 or multiples thereof for the American Century STOXX® U.S. Quality Value ETF and 50,000 or multiples thereof for the American Century Diversified Corporate Bond ETF.
The trust reserves the right to permit or require that creations and redemptions of shares are effected fully or partially in cash. Shares may be issued in advance of receipt of Deposit Securities, subject to various conditions, including a requirement to maintain with the trust a cash deposit equal to at least 105% and up to 115%, which percentage the trust may change from time to time, of the market value of the omitted Deposit Securities. See Creation and Redemption of Creation Units, page 32 of this SAI. Transaction fees and other costs associated with creations or redemptions that include a cash portion may be higher than the transaction fees and other costs associated with in-kind creations or redemptions. In all cases, transaction fees will be limited in accordance with the requirements of U.S. Securities and Exchange Commission (SEC) rules and regulations applicable to management investment companies offering redeemable securities.
Exchange Listing and Trading
A discussion of exchange listing and trading matters associated with an investment in each fund is contained in the Investing in the Fund section of that fund’s prospectus. The discussion below supplements, and should be read in conjunction with, that section of each prospectus.
Shares of the funds are listed for trading, and trade throughout the day, on the Listing Exchange and in other secondary markets. Shares of the funds may also be listed on certain non-U.S. exchanges. There can be no assurance that the requirements of the Listing Exchange necessary to maintain the listing of shares of the fund will continue to be met. The Listing Exchange may, but is not required to, remove the shares of a fund from listing if (i) following the initial 12-month period beginning upon the commencement of trading of fund shares, there are fewer than 50 beneficial owners of shares of the fund, (ii) with respect to the American Century STOXX U.S. Quality Value ETF, the value of the underlying index on which the fund is based (underlying index) is no longer calculated or available, (iii) the “indicative optimized portfolio value” (IOPV) of the fund is no longer calculated or available, or (iv) any other event shall occur or condition shall exist that, in the opinion of the Listing Exchange, makes further dealings on the Listing Exchange inadvisable. The Listing Exchange will also remove shares of a fund from listing and trading upon termination of the fund.
As in the case of other publicly traded securities, when you buy or sell shares through a broker, you will incur a brokerage commission determined by that broker.
In order to provide additional information regarding the indicative value of shares of a fund, the Listing Exchange or a market data vendor disseminates information every 15 seconds through the facilities of the Consolidated Tape Association, or through other widely disseminated means, an updated IOPV for the fund as calculated by an information provider or market data vendor. The trust is not involved in or responsible for any aspect of the calculation or dissemination of the IOPVs and makes no representation or warranty as to the accuracy of the IOPVs.
The IOPV of the American Century STOXX® U.S. Quality Value ETF is based on the current market value of the Deposit Securities and the Cash Component and the IOPV of the American Century Diversified Corporate Bond ETF is based on the current market value of the securities and/or cash contained in the portfolio at the beginning of the trading day. The IOPV does not necessarily reflect the best possible valuation of the current portfolio of securities held by a fund and may not be calculated in the same manner as the NAV. While the IOPV of the American Century STOXX® U.S. Quality Value ETF reflects the current value of the Deposit Securities required to be deposited in connection with the purchase of a Creation Unit, it does not necessarily reflect the precise composition of the current portfolio of securities held by a fund at a particular point in time because the current portfolio of the fund may include securities that are not a part of the current Deposit Securities. Therefore, a fund’s IOPV disseminated during the Listing Exchange trading hours should not be viewed as a real-time update of the fund’s NAV, which is calculated only once a day. Each fund’s IOPV is not calculated by the fund.

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The cash component included in an IOPV may consist of other assets held by a fund, including cash, estimated accrued interest, dividends and other income, less expenses. If applicable, each IOPV also reflects changes in currency exchange rates between the U.S. dollar and the applicable currency.
The trust reserves the right to adjust the share prices of a fund in the future to maintain convenient trading ranges for investors. Any adjustments would be accomplished through stock splits or reverse stock splits, which would have no effect on the net assets of the fund or an investor’s equity interest in the fund.
Fund Investment Guidelines
This section explains the extent to which the funds’ advisor, American Century Investment Management, Inc. (ACIM or the advisor), can use various investment vehicles and strategies in managing a fund’s assets. Descriptions of the investment techniques and risks associated with each appear in the section, Investment Strategies and Risks, which begins on page 4 . In the case of the funds’ principal investment strategies, these descriptions elaborate upon discussions contained in the prospectuses.
The American Century STOXX® U.S. Quality Value ETF is an index-based exchange-traded fund (ETF) and is not actively managed. Adverse performance of a security in the fund’s portfolio will ordinarily not result in the elimination of the security from the fund’s portfolio. Under normal market conditions, the fund invests at least 80% of its assets, exclusive of collateral held from securities lending, in the component securities of the underlying index. The fund may invest in cash and cash equivalents, including shares of affiliated money market funds, as well as in securities not included in the underlying index, but which ACIM believes will help the fund track its underlying index. The fund may use a representative sampling strategy whereby the fund would invest in what it believes to be a representative sample of the component securities included of the underlying index. Under the representative sampling technique, the portfolio managers will select securities that collectively have an investment profile similar to that of the underlying index, including securities that resemble those included in the underlying index in terms of risk factors, performance attributes and other characteristics, such as market capitalization and industry weights. To the extent the fund uses representative sampling, it may not hold all of the securities that are in its underlying index or it may hold other securities that are not included in its underlying index.
The American Century Diversified Corporate Bond ETF is an actively managed ETF that invests primarily in corporate debt securities. In general, within the restrictions outlined here and in the fund’s prospectus, the portfolio managers have broad powers to decide how to invest fund assets. Investments in the fund vary according to what is judged advantageous under changing economic conditions. It is the advisor’s policy to retain maximum flexibility in management without restrictive provisions as to the proportion of one or another class of securities that may be held, subject to the investment restrictions described on the following pages.
In addition to the main types of investments and strategies undertaken by the funds as described in the prospectuses, the funds also may invest in other types of instruments and engage in and pursue other investment strategies, which are described in this SAI. Investments and investment strategies with respect to the funds are discussed in greater detail in the section below entitled Investment Strategies and Risks.
Incidental to a fund’s other investment activities, including in connection with a bankruptcy, restructuring, workout, or other extraordinary events concerning a particular investment a fund owns, the fund may receive securities (including convertible securities, warrants and rights), real estate or other investments that the fund normally would not, or could not, buy. If this happens, the fund may, although it is not required to, sell such investments as soon as practicable while seeking to maximize the return to shareholders.
The funds are diversified as defined in the Investment Company Act of 1940 (the Investment Company Act). Diversified means that, with respect to 75% of its total assets, each fund will not invest more than 5% of its total assets in the securities of a single issuer or own more than 10% of the outstanding voting securities of a single issuer (other than the U.S. government and securities of other investment companies).
To meet federal tax requirements for qualification as a regulated investment company, each fund must limit its investments so that at the close of each quarter of its taxable year (1) no more than 25% of its total assets are invested in the securities of a single issuer (other than the U.S. government or a regulated investment company), and (2) with respect to at least 50% of its total assets, no more than 5% of its total assets are invested in the securities of a single issuer (other than the U.S. government or a regulated investment company) and it does not own more than 10% of the outstanding voting securities of a single issuer.
Unless otherwise noted, all investment restrictions described below and in each fund’s prospectus are measured at the time of the transaction in the security.  If market action affecting fund securities (including, but not limited to, appreciation, depreciation or a credit rating event) causes a fund to exceed an investment restriction, the advisor is not required to take immediate action.  Under normal market conditions, however, the advisor’s policies and procedures indicate that the advisor will not make any purchases that will make the fund further outside the investment restriction.
For temporary defensive purposes, the American Century Diversified Corporate Bond ETF may invest without limit in securities that are inconsistent with the fund’s principal investment strategies, such as cash, cash equivalents, money market instruments or

3



other high quality short-term investments. Senior securities that are high-grade issues, in the opinion of the managers, also may be purchased for defensive purposes. To the extent the fund assumes a defensive position, it may not achieve its investment objective.
The managers may use futures and options as a way to expose the funds’ cash assets to the market while maintaining liquidity. The managers may not leverage a fund’s portfolio without appropriately segregating assets to cover such positions. See Derivative Instruments, page 8 , Futures and Options, page 10 and Short-Term Securities, page 22 .
Fund Investments and Risks
Investment Strategies and Risks
This section describes investment vehicles and techniques the portfolio managers can use in managing a fund’s assets. It also details the risks associated with each, because each investment vehicle and technique contributes to a fund’s overall risk profile.
Asset-Backed Securities (ABS)
The American Century Diversified Corporate Bond ETF may invest in ABS. ABS are structured like mortgage-backed securities, but instead of mortgage loans or interest in mortgage loans, the underlying assets may include, for example, such items as motor vehicle installment sales or installment loan contracts, leases of various types of real and personal property, home equity loans, student loans, small business loans, and receivables from credit card agreements. The ability of an issuer of ABS to enforce its security interest in the underlying assets may be limited. The value of an ABS is affected by changes in the market’s perception of the assets backing the security, the creditworthiness of the servicing agent for the loan pool, the originator of the loans, the financial institution providing any credit enhancement, and subordination levels.
Payments of principal and interest passed through to holders of ABS are typically supported by some form of credit enhancement, such as a letter of credit, surety bond, limited guarantee by another entity or a priority to certain of the borrower’s other securities. The degree of credit enhancement varies, and generally applies to only a fraction of the ABS’s par value until exhausted. If the credit enhancement of an ABS held by the fund has been exhausted, and if any required payments of principal and interest are not made with respect to the underlying loans, the fund may experience losses or delays in receiving payment.
Some types of ABS may be less effective than other types of securities as a means of “locking in” attractive long-term interest rates. One reason is the need to reinvest prepayments of principal; another is the possibility of significant unscheduled prepayments resulting from declines in interest rates. These prepayments would have to be reinvested at lower rates. As a result, these securities may have less potential for capital appreciation during periods of declining interest rates than other securities of comparable maturities, although they may have a similar risk of decline in market value during periods of rising interest rates. Prepayments may also significantly shorten the effective maturities of these securities, especially during periods of declining interest rates. Conversely, during periods of rising interest rates, a reduction in prepayments may increase the effective maturities of these securities, subjecting them to a greater risk of decline in market value in response to rising interest rates than traditional debt securities, and, therefore, potentially increasing the volatility of the fund.
The risks of investing in ABS are ultimately dependent upon the repayment of loans by the individual or corporate borrowers. Although the fund would generally have no recourse against the entity that originated the loans in the event of default by a borrower, ABS typically are structured to mitigate this risk of default.
ABS are generally issued in more than one class, each with different payment terms. Multiple class ABS may be used as a method of providing credit support through creation of one or more classes whose right to payments is made subordinate to the right to such payments of the remaining class or classes. Multiple classes also may permit the issuance of securities with payment terms, interest rates or other characteristics differing both from those of each other and from those of the underlying assets. Examples include so-called strips (ABS entitling the holder to disproportionate interests with respect to the allocation of interest and principal of the assets backing the security), and securities with classes having characteristics such as floating interest rates or scheduled amortization of principal.
Bank Loans
The American Century Diversified Corporate Bond ETF may invest in bank loans, which include senior secured and unsecured floating rate loans of corporations, partnerships, or other entities. Typically, these loans hold a senior position in the borrower’s capital structure, may be secured by the borrower’s assets and have interest rates that reset frequently. These loans are usually rated non-investment grade by the rating agencies. An economic downturn generally leads to higher non-payment and default rates by borrowers, and a bank loan can lose a substantial part of its value due to these and other adverse conditions and events. However, as compared to junk bonds, senior floating rate loans are typically senior in the capital structure and are often secured by collateral of the borrower. The fund’s investments in bank loans are subject to credit risk, and there is no assurance that the liquidation of collateral would satisfy the claims of the borrower’s obligations in the event of non-payment of scheduled interest or principal, or that the collateral could be readily liquidated. The interest rates on many bank loans reset frequently, and therefore investors are subject to the risk that the return will be less than anticipated when the investment was first made. Most bank loans, like most

4



investment grade bonds, are not traded on any national securities exchange. Bank loans generally have less liquidity than investment grade bonds and there may be less publicly available information about them.
A fund eligible to invest in bank loans may purchase bank loans from other lenders (sometimes referred to as loan assignments) or it may also acquire a participation interest in another lender’s portion of the bank loan. Large bank loans to corporations or governments may be shared or syndicated among several lenders, usually commercial or investment banks. The fund may participate in such syndicates, or can buy part of a loan, becoming a direct lender. Participation interests involve special types of risk, including liquidity risk and the risks of being a lender. Risks of being a lender include credit risk (the borrower’s ability to meet required principal and interest payments under the terms of the loan), industry risk (the borrower’s industry’s exposure to rapid change or regulation), financial risk (the effectiveness of the borrower’s financial policies and use of leverage), liquidity risk (the adequacy of the borrower’s back-up sources of cash), and collateral risk (the sufficiency of the collateral’s value to repay the loan in the event of non-payment or default by the borrower). If the fund purchases a participation interest, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the credit risk of the borrower.
In addition, transactions in bank loans may take more than seven days to settle. As a result, the proceeds from the sale of bank loans may not be readily available to make additional investments or to meet the fund’s redemption obligations. To mitigate these risks, the fund monitors its short-term liquidity needs in light of the longer settlement period of bank loans. Some bank loan interests may not be registered under the Securities Act of 1933 (1933 Act) and therefore not afforded the protections of the federal securities laws.
Bank Obligations
Each fund may invest in certain types of bank obligations. Negotiable certificates of deposit (CDs) evidence a bank’s obligation to repay money deposited with it for a specified period of time. The following table identifies the types of CDs the funds may buy.
CD Type
Issuer
Domestic
Domestic offices of U.S. banks
Yankee
U.S. branches of foreign banks
Eurodollar
Issued in London by U.S., Canadian, European and Japanese banks
Schedule B
Canadian subsidiaries of non-Canadian banks
To the extent permitted by its investment objective and policies, the funds may also buy bankers’ acceptances, bank notes and time deposits. Bankers’ acceptances are used to finance foreign commercial trade. Issued by a bank with an importer’s name on them, these instruments allow the importer to back up its own pledge to pay for imported goods with a bank’s obligation to cover the transaction if the importer fails to do so.
Bank notes are senior unsecured promissory notes issued in the United States by domestic commercial banks.
Time deposits are non-negotiable bank deposits maintained for up to seven days at a stated interest rate. These instruments may be withdrawn on demand, although early withdrawals may be subject to penalties.
The bank obligations the portfolio managers may buy generally are not insured by the FDIC or any other insurer.
Collateralized Debt Obligations
The American Century Diversified Corporate Bond ETF may invest in collateralized debt obligations (“CDOs”), including collateralized loan obligations (“CLOs”), collateralized bond obligations (“CBOs”), and other similarly structured investments. CBOs and CLOs are types of asset backed securities. A CLO is a trust or other special purpose entity that is typically collateralized by a pool of loans, which may include, among others, U.S. and non-U.S. senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. A CBO is generally a trust which is backed by a diversified pool of high risk, below investment grade fixed-income securities. The risks of an investment in a CDO depend largely on the type of the collateral backing the obligation and the class of the CDO in which the fund invests. CDOs are subject to credit, interest rate, valuation, prepayment and extension risks. These securities are also subject to risk of default on the underlying asset, particularly during periods of economic downturn. CDOs carry additional risks including, but not limited to, (i) the possibility that distributions from collateral securities will not be adequate to make interest or other payments, (ii) the collateral may decline in value or default, (iii) the fund may invest in CDOs that are subordinate to other classes, and (iv) the complex structure of the security may not be fully understood at the time of investment and may produce disputes with the issuer or unexpected investment results.
Commercial Paper
The funds may invest in commercial paper (CP) that is issued by utility, financial, and industrial companies, supranational organizations and foreign governments and their agencies and instrumentalities. Rating agencies assign ratings to short-term securities (including CP) issuers indicating the agencies’ assessment of credit risk. Short-term ratings assigned by certain rating agencies are provided in the Explanation of Fixed-Income Securities Ratings, Appendix A.
Some examples of CP and CP issuers are provided in the following paragraphs.

5



Domestic CP is issued by U.S. industrial and finance companies, utility companies, thrifts and bank holding companies. Foreign CP is issued by non-U.S. industrial and finance companies and financial institutions. Domestic and foreign corporate issuers occasionally have the underlying support of a well-known, highly rated commercial bank or insurance company. Bank support is provided in the form of a letter of credit (an LOC) or irrevocable revolving credit commitment (an IRC). Insurance support is provided in the form of a surety bond.
Bank holding company CP is issued by the holding companies of many well-known domestic banks, including Citicorp, J.P. Morgan Chase & Company and First Union National Bank. Bank holding company CP may be issued by the parent of a money center or regional bank.
Thrift CP is issued by major federal- or state-chartered savings and loan associations and savings banks.
Schedule B Bank CP is short-term, U.S. dollar-denominated CP issued by Canadian subsidiaries of non-Canadian banks (Schedule B banks). Whether issued as CP, a certificate of deposit or a promissory note, each instrument issued by a Schedule B bank ranks equally with any other deposit obligation. CP issued by Schedule B banks provides an investor with the comfort and reduced risk of a direct and unconditional parental bank guarantee. Schedule B instruments generally offer higher rates than the short-term instruments of the parent bank or holding company.
Asset-backed CP is issued by corporations through special programs. In a typical program, a special purpose corporation (SPC), created and/or serviced by a bank or other financial institution, uses the proceeds from an issuance of CP to purchase receivables or other financial assets from one or more corporations (sellers). The sellers transfer their interest in the receivables or other financial assets to the SPC, and the cash flow from the receivables or other financial assets is used to pay interest and principal on the CP. Letters of credit or other forms of credit enhancement may be available to cover the risk that the cash flow from the receivables or other financial assets will not be sufficient to cover the maturing CP.
Convertible Securities
The funds may invest in convertible securities. A convertible security is a bond, debenture, note, preferred stock or other security that may be converted into or exchanged for a prescribed amount of common stock of the same or a different issuer within a particular time period at a specified price or formula. A convertible security entitles the holder to receive the interest paid or accrued on debt or the dividend paid on preferred stock until the convertible security matures or is redeemed, converted or exchanged. Before conversion or exchange, such securities ordinarily provide a stream of income with generally higher yields than common stocks of the same or similar issuers, but lower than the yield on non-convertible debt. Of course, there can be no assurance of current income because issuers of convertible securities may default on their obligations. In addition, there can be no assurance of capital appreciation because the value of the underlying common stock will fluctuate. Because of the conversion feature, the managers generally consider convertible securities to be equity equivalents.
The price of a convertible security will normally fluctuate in some proportion to changes in the price of the underlying asset. A convertible security is subject to risks relating to the activities of the issuer and/or general market and economic conditions. The stream of income typically paid on a convertible security may tend to cushion the security against declines in the price of the underlying asset. However, the stream of income causes fluctuations based upon changes in interest rates and the credit quality of the issuer. In general, the value of a convertible security is a function of (1) its yield in comparison with yields of other securities of comparable maturity and quality that do not have a conversion privilege and (2) its worth, at market value, if converted or exchanged into the underlying common stock. The price of a convertible security often reflects such variations in the price of the underlying common stock in a way that a non-convertible security does not. At any given time, investment value generally depends upon such factors as the general level of interest rates, the yield of similar nonconvertible securities, the financial strength of the issuer and the seniority of the security in the issuer’s capital structure.
A convertible security may be subject to redemption at the option of the issuer at a predetermined price. If a convertible security held by the fund is called for redemption, the fund would be required to permit the issuer to redeem the security and convert it to underlying common stock or to cash, or would sell the convertible security to a third party, which may have an adverse effect on the fund. A convertible security may feature a put option that permits the holder of the convertible security to sell that security back to the issuer at a predetermined price. The fund generally invests in convertible securities for their favorable price characteristics and total return potential and normally would not exercise an option to convert unless the security is called or conversion is forced.
Unlike a convertible security that is a single security, a synthetic convertible security is comprised of two distinct securities that together resemble convertible securities in certain respects. Synthetic convertible securities are created by combining non-convertible bonds or preferred stocks with warrants or stock call options. The options that will form elements of synthetic convertible securities will be listed on a securities exchange or NASDAQ. The two components of a synthetic convertible security, which will be issued with respect to the same entity, generally are not offered as a unit, and may be purchased and sold by the fund at different times. Synthetic convertible securities differ from convertible securities in certain respects. Each component of a synthetic convertible security has a separate market value and responds differently to market fluctuations. Investing in a synthetic convertible security involves the risk normally found in holding the securities comprising the synthetic convertible security.

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Counterparty Risk
A fund will be exposed to the credit risk of the counterparties with which, or the brokers, dealers and exchanges through which, it deals, whether it engaged in exchange traded or off-exchange transactions.  If a fund’s futures commission merchant (FCM) becomes bankrupt or insolvent, or otherwise defaults on its obligations to the fund, the fund may not receive all amounts owed to it in respect of its trading, despite the clearinghouse fully discharging all of its obligations.  The Commodity Exchange Act requires an FCM to segregate all funds received from its customers with respect to regulated futures transactions from such FCM’s proprietary funds.  If an FCM were not to do so to the full extent required by law, the assets of an account might not be fully protected in the event of the bankruptcy of an FCM.  Furthermore, in the event of an FCM’s bankruptcy, a fund would be limited to recovering only a pro rata share of all available funds segregated on behalf of an FCM’s combined customer accounts, even though certain property specifically traceable to the fund (for example, U.S. Treasury bills deposited by the fund) was held by an FCM.  FCM bankruptcies have occurred in which customers were unable to recover from the FCM’s estate the full amount of their funds on deposit with such FCM and owing to them.  Such situations could arise due to various factors, or a combination of factors, including inadequate FCM capitalization, inadequate controls on customer trading and inadequate customer capital.  In addition, in the event of the bankruptcy or insolvency of a clearinghouse, the fund might experience a loss of funds deposited through its FCM as margin with the clearinghouse, a loss of unrealized profits on its open positions, and the loss of funds owed to it as realized profits on closed positions.  Such a bankruptcy or insolvency might also cause a substantial delay before the fund could obtain the return of funds owed to it by an FCM who was a member of such clearinghouse.
Because bi-lateral derivative transactions are traded between counterparties based on contractual relationships, a fund is subject to the risk that a counterparty will not perform its obligations under the related contracts.  Although each fund intends to enter into transactions only with counterparties which the advisor believes to be creditworthy, there can be no assurance that a counterparty will not default and that the funds will not sustain a loss on a transaction as a result. In situations where a fund is required to post margin or other collateral with a counterparty, the counterparty may fail to segregate the collateral or may commingle the collateral with the counterparty’s own assets.  As a result, in the event of the counterparty’s bankruptcy or insolvency, a fund’s collateral may be subject to the conflicting claims of the counterparty’s creditors, and a fund may be exposed to the risk of a court treating a fund as a general unsecured creditor of the counterparty, rather than as the owner of the collateral.
A fund is subject to the risk that issuers of the instruments in which it invests and trades may default on their obligations under those instruments, and that certain events may occur that have an immediate and significant adverse effect on the value of those instruments.  There can be no assurance that an issuer of an instrument in which a fund invests will not default, or that an event that has an immediate and significant adverse effect on the value of an instrument will not occur, and that a fund will not sustain a loss on a transaction as a result.
Transactions entered into by a fund may be executed on various U.S. and non-U.S. exchanges, and may be cleared and settled through various clearinghouses, custodians, depositories and prime brokers throughout the world.  Although a fund attempts to execute, clear and settle the transactions through entities the advisor believes to be sound, there can be no assurance that a failure by any such entity will not lead to a loss to a fund.
Cyber Security Risk
As the funds increasingly rely on technology and information systems to operate, they become susceptible to operational risks linked to security breaches in those information systems. Both calculated attacks and unintentional events can cause failures in the funds’ information systems. Cyber attacks can include acquiring unauthorized access to information systems, usually through hacking or the use of malicious software, for purposes of stealing assets or confidential information, corrupting data, or disrupting fund operations. Cyber attacks can also occur without direct access to information systems, for example by making network services unavailable to intended users. Cyber security failures by, or breaches of the information systems of, the advisor, distributors, broker-dealers, other service providers (including, but not limited to, index providers, fund accountants, custodians, transfer agents and administrators), or the issuers of securities the funds invest in may also cause disruptions and impact the funds’ business operations.  Breaches in information security may result in financial losses, interference with the funds’ ability to calculate NAV, impediments to trading, inability of fund shareholders to transact business, violations of applicable privacy and other laws, regulatory fines, penalties, reputational damage, reimbursement or other compensation costs, or additional compliance costs. Additionally, the funds may incur substantial costs to prevent future cyber incidents. The funds have business continuity plans in the event of, and risk management systems to help prevent, such cyber attacks, but these plans and systems have limitations including the possibility that certain risks have not been identified. Moreover, the funds do not control the cyber security plans and systems of their service providers and other third party business partners. The funds and their shareholders could be negatively impacted as a result.
Debt Securities
The value of the debt securities in which the American Century Diversified Corporate Bond ETF may invest will fluctuate based upon changes in interest rates and the credit quality of the issuer. Debt securities will be limited primarily to “investment-grade” obligations. However, the fund may invest up to 35% of its net assets in “high-yield” debt securities (which are also known as “junk bonds”). “Investment grade” means that at the time of purchase, such obligations are rated within the four highest categories

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by a nationally recognized statistical rating organization (for example, at least Baa by Moody’s Investors Service, Inc. or BBB by Standard & Poor’s Corporation), or, if not rated, are of equivalent investment quality as determined by the advisor. According to Moody’s, bonds rated Baa are medium-grade and possess some speculative characteristics. A BBB rating by S&P indicates S&P’s belief that a security exhibits a satisfactory degree of safety and capacity for repayment, but is more vulnerable to adverse economic conditions and changing circumstances.
“High-yield” securities are higher risk, non-convertible debt obligations that are rated below investment-grade securities, or are unrated, but with similar credit quality.
There are no credit or maturity restrictions on the fixed-income securities in which the high-yield portion of the fund’s portfolio may be invested. Debt securities rated lower than Baa by Moody’s or BBB by S&P, or their equivalent, are considered by many to be predominantly speculative. Changes in economic conditions or other circumstances are more likely to lead to a weakened capacity to make principal and interest payments on such securities than is the case with higher quality debt securities. Regardless of rating levels, all debt securities considered for purchase by the fund are analyzed by the investment manager to determine, to the extent reasonably possible, that the planned investment is sound, given the fund’s investment objective. See Explanation of Fixed-Income Securities Ratings in Appendix A.
In addition, the value of the fund’s investments in fixed-income securities will change as prevailing interest rates change. In general, the prices of such securities vary inversely with interest rates. As prevailing interest rates fall, the prices of bonds and other securities that trade on a yield basis generally rise. When prevailing interest rates rise, bond prices generally fall. Depending upon the particular amount and type of fixed-income securities holdings of the fund, these changes may impact the net asset value of the fund’s shares.
Derivative Instruments
To the extent permitted by its investment objectives and policies, each fund may invest in instruments that are commonly referred to as derivative instruments. Generally, a derivative instrument is a financial arrangement, the value of which is based on, or derived from, a traditional security, asset, or market index. Examples of common derivative instruments include futures contracts, warrants, structured notes, credit default swaps, options contracts, swap transactions and forward currency contracts.
Certain derivative instruments are described more accurately as index/structured investments. Index/structured investments are derivative instruments whose value or performance is linked to other equity securities, currencies, interest rates, indices or other financial indicators (reference indices). A structured investment is a security whose value or performance is linked to an underlying index or other security or asset class. Structured investments include asset-backed securities (ABS), asset-backed commercial paper (ABCP), commercial and residential mortgage-backed securities (MBS), collateralized debt obligations (CDO), collateralized loan obligations (CLO), and securities backed by other types of collateral or indices. Structured investments involve the transfer of specified financial assets to a special purpose entity, generally a corporation or trust, or the deposit of financial assets with a custodian; and the issuance of securities or depositary receipts backed by, or representing interests in those assets.
Some structured investments are individually negotiated agreements or are traded over the counter. Structured investments may be organized and operated to restructure the investment characteristics of the underlying security. The cash flow on the underlying instruments may be apportioned among the newly issued structured investments to create securities with different investment characteristics, such as varying maturities, payment priorities and interest rate provisions, and the extent of such payments made with respect to structured investments is dependent on the extent of the cash flow on the underlying instruments. Because structured investments typically involve no credit enhancement, their credit risk generally will be equivalent to that of the underlying instruments. In addition, structured investments are subject to the risks that the issuers of the underlying securities may be unable or unwilling to repay principal and interest (credit risk) and may request to reschedule or restructure outstanding debt and to extend additional loan amounts (prepayment risk).
Some derivative instruments, such as mortgage-related and other ABS, are in many respects like any other investment, although they may be more volatile or less liquid than more traditional debt securities.
There are many different types of derivative instruments and many different ways to use them. Futures and options are commonly used for traditional hedging purposes to attempt to protect a fund from exposure to changing interest rates, securities prices or currency exchange rates, and for cash management purposes as a low-cost method of gaining exposure to a particular securities market without investing directly in those securities.
The return on a derivative instrument may increase or decrease, depending upon changes in the reference index or instrument to which it relates.
There is a range of risks associated with investments in derivatives, including:
the risk that the underlying security, interest rate, market index or other financial asset will not move in the direction the portfolio managers anticipate or that the value of the structured or derivative instrument will not move or react to changes in the underlying security, interest rate, market index or other financial asset as anticipated;
the possibility that there may be no liquid secondary market, which may make it difficult or impossible to close out a position when desired;

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the risk that daily limits on price fluctuations and speculative position limits on exchanges on which a fund may conduct its transactions in derivative instruments may prevent profitable liquidation of positions, subjecting a fund to the potential of greater losses;
the risk that adverse price movements in an instrument can result in a loss substantially greater than a fund’s initial investment;
the risk that a fund will have an obligation to deliver securities pursuant to a derivatives transaction that such fund does not own at the inception of the derivative trade;
the risk that the counterparty will fail to perform its obligations; and
the risk that a fund will be subject to higher volatility because some derivative instruments create leverage.
The funds’ Board of Trustees has reviewed the advisor’s policy regarding investments in derivative instruments. That policy specifies factors that must be considered in connection with a purchase of derivative instruments. The policy also establishes a committee that must review certain proposed purchases before the purchases can be made. The advisor will report on fund activity in derivative instruments to the Board of Trustees as necessary.
Distressed Investments
The American Century Diversified Corporate Bond ETF may invest in certain types of distressed investments. Distressed investments generally entail greater risks due to such things as sensitivity to general economic and capital market conditions, interest rates, risks associated with leveraged companies and risks inherent in investing in companies experiencing financial and operating distress (e.g., issuer credit risk). Distressed investments generally have very low credit ratings or are unrated by credit rating agencies.
Greater Risk of Loss - These investments are regarded as highly speculative. There is a greater risk that issuers of lower-rated investments will default than issuers of higher-rated investments, and some may be subject to bankruptcy proceedings or may be in default as to the repayment of principal and/or interest. Issuers of lower-rated investments generally are more vulnerable to real or perceived economic changes, political changes or adverse industry developments. In addition, distressed debt investments are frequently subordinated to the prior payment of senior indebtedness or have claims that are otherwise junior in priority with regard to the issuer’s assets. If an issuer fails to pay principal or interest, the fund would experience a decrease in income and a decline in the market value of its investments. These investments carry a much greater risk of default and loss, which could include the loss of the entire amount of the investment.
Valuation Difficulties - It is often more difficult to value distressed and other lower-rated investments than higher-rated investments. If an issuer’s financial condition deteriorates, accurate financial and business information may be limited or unavailable. In addition, lower-rated investments may be thinly traded and there may be no established secondary market. Because of the lack of market pricing and current information for investments in some distressed and lower-rated investments, valuation of such investments is much more dependent on judgment than is the case with higher-rated investments.
Liquidity - There may be no established secondary or public market for investments in distressed and other lower-rated investments. Such investments generally are traded in markets that are less liquid than the market for higher-rated investments. In addition, relatively few institutional purchasers may hold a major portion of an issue of lower-rated investments. As a result, the fund may be required to sell investments at substantial losses, or may be unable to sell investments.
Equity Securities and Equity Equivalent Securities
In addition to investing in common stocks, the funds may invest in other equity securities and equity equivalents, including securities that permit a fund to receive an equity interest in an issuer, the opportunity to acquire an equity interest in an issuer, or the opportunity to receive a return on its investment that permits the fund to benefit from the growth over time in the equity of an issuer. Examples of equity securities and equity equivalents include common stock, preferred stock, securities convertible into common stock, stock futures contracts and stock index futures contracts.
Equity equivalents also may include securities whose value or return is derived from the value or return of a different security.
Foreign Securities
The American Century Diversified Corporate Bond ETF may invest in U.S. dollar-denominated foreign securities, including securities of issuers located in developed foreign countries and emerging market countries.
Direct investments in foreign securities may be made either on foreign securities exchanges or in the over-the-counter markets.
As permitted by its investment objective and principal investment strategies, the fund may invest in common stocks, convertible securities, preferred stocks, bonds, notes and other debt securities of foreign issuers, foreign governments and their agencies.
Investments in foreign securities generally involve greater risks than investing in securities of domestic companies, including:
Social, Political and Economic Risk - The economies of many of the countries in which the fund invests are not as developed as the economy of the United States and may be subject to significantly different forces. Political or social instability, expropriation, nationalization, confiscatory taxation and limitations on the removal of funds or other assets also could adversely affect the value

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of investments. Further, the fund may find it difficult or be unable to enforce ownership rights, pursue legal remedies or obtain judgments in foreign courts.
Regulatory Risk - Foreign companies generally are not subject to the regulatory controls imposed on U.S. issuers and, in general, there is less publicly available information about foreign securities than is available about domestic securities. Many foreign companies are not subject to uniform accounting, auditing and financial reporting standards, practices and requirements comparable to those applicable to domestic companies and there may be less stringent investor protection and disclosure standards in some foreign markets. Income from foreign securities owned by the fund may be reduced by a withholding tax at the source, which would reduce dividend income payable to shareholders.
Market and Trading Risk - Brokerage commission rates in foreign countries, which generally are fixed rather than subject to negotiation as in the United States, are likely to be higher. The securities markets in many of the countries in which the fund invests have substantially less trading volume than the principal U.S. markets. As a result, the securities of some companies in these countries may be less liquid, more volatile and harder to value than comparable U.S. securities. Furthermore, one securities broker may represent all or a significant part of the trading volume in a particular country, resulting in higher trading costs and decreased liquidity due to a lack of alternative trading partners. There generally is less government regulation and supervision of foreign stock exchanges, brokers and issuers, which may make it difficult to enforce contractual obligations.
Clearance and Settlement Risk - Foreign securities markets also have different clearance and settlement procedures, and in certain markets there have been times when settlements have been unable to keep pace with the volume of securities transactions, making it difficult to conduct such transactions. Delays in clearance and settlement could result in temporary periods when assets of the fund are uninvested and no return is earned. The fund’s inability to make intended security purchases due to clearance and settlement problems could cause them to miss attractive investment opportunities. Inability to dispose of portfolio securities due to clearance and settlement problems could result either in losses to the fund due to subsequent declines in the value of the portfolio security or, if the fund has entered into a contract to sell the security, liability to the purchaser.
Ownership Risk - Evidence of securities ownership may be uncertain in many foreign countries. As a result, there may be a risk that the fund’s trade details could be incorrectly or fraudulently entered at the time of the transaction, resulting in a loss to the fund.
Sanctions - The U.S. may impose economic sanctions against companies in various sectors of certain countries. This could limit the fund’s investment opportunities in such countries, impairing the fund’s ability to invest in accordance with its investment strategy and/or to meet its investment objective. For example, the fund may be prohibited from investing in securities issued by companies subject to such sanctions. In addition, the sanctions may require a fund to freeze its existing investments in sanctioned companies, prohibiting the fund from selling or otherwise transacting in these investments. Current sanctions or the threat of potential sanctions may also impair the value or liquidity of affected securities and negatively impact the fund.
Emerging Markets Risk – The fund may invest its holdings in securities of issuers located in emerging market (developing) countries. The funds consider “emerging market countries” to include all countries other than the following list of developed countries, which is subject to change: Australia, Austria, Belgium, Bermuda, Canada, Denmark, Finland, France, Germany, Hong Kong, Ireland, Israel, Italy, Japan, the Netherlands, New Zealand, Norway, Portugal, Singapore, Spain, Sweden, Switzerland, the United Kingdom and the United States.
Investing in securities of issuers in emerging market countries involves exposure to significantly higher risk than investing in countries with developed markets. Emerging market countries may have economic structures that generally are less diverse and mature, and political systems that can be expected to be less stable than those of developed countries.
Securities prices in emerging market countries can be significantly more volatile than in developed countries, reflecting the greater uncertainties of investing in lesser developed markets and economies. In particular, emerging market countries may have relatively unstable governments, and may present the risk of nationalization of businesses, expropriation, confiscatory taxation or in certain instances, reversion to closed-market, centrally planned economies. Such countries may also have less protection of property rights than developed countries.
The economies of emerging market countries may be based predominantly on only a few industries or may be dependent on revenues from particular commodities or on international aid or developmental assistance, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme and volatile debt burdens or inflation rates. In addition, securities markets in emerging market countries may trade a relatively small number of securities and may be unable to respond effectively to increases in trading volume, potentially resulting in a lack of liquidity and in volatility in the price of securities traded on those markets. Also, securities markets in emerging market countries typically offer less regulatory protection for investors.
Futures and Options
Each fund may enter into futures contracts, options and options on futures contracts. Futures contracts provide for the sale by one party and purchase by another party of a specific security at a specified future time and price. Generally, futures transactions will be used to:
protect against a decline in market value of a fund’s securities (taking a short futures position),

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protect against the risk of an increase in market value for securities in which a fund generally invests at a time when the fund is not fully invested (taking a long futures position), or
provide a temporary substitute for the purchase of an individual security that may not be purchased in an orderly fashion.
Some futures and options strategies, such as selling futures, buying puts and writing calls, hedge a fund’s investments against price fluctuations. Other strategies, such as buying futures, writing puts and buying calls, tend to increase market exposure.
Although other techniques may be used to control a fund’s exposure to market fluctuations, the use of futures contracts may be a more effective means of hedging this exposure. While a fund pays brokerage commissions in connection with opening and closing out futures positions, these costs are lower than the transaction costs incurred in the purchase and sale of the underlying securities.
For example, the sale of a future by a fund means the fund becomes obligated to deliver the security (or securities, in the case of an index future) at a specified price on a specified date. The purchase of a future means the fund becomes obligated to buy the security (or securities) at a specified price on a specified date. The portfolio managers may engage in futures and options transactions, provided that the transactions are consistent with the fund’s investment objectives. An example of an index that may be used is the S&P 500 Index for equity funds. The managers may engage in futures and options transactions based on specific securities. Futures contracts are traded on national futures exchanges. Futures exchanges and trading are regulated under the Commodity Exchange Act by the Commodity Futures Trading Commission (CFTC), a U.S. government agency.
Index futures contracts differ from traditional futures contracts in that when delivery takes place, no stocks or bonds change hands. Instead, these contracts settle in cash at the spot market value of the index. Although other types of futures contracts by their terms call for actual delivery or acceptance of the underlying securities, in most cases the contracts are closed out before the settlement date. A futures position may be closed by taking an opposite position in an identical contract (i.e., buying a contract that has previously been sold or selling a contract that has previously been bought).
Unlike when a fund purchases or sells a security, no price is paid or received by the fund upon the purchase or sale of the future. Initially, the fund will be required to deposit an amount of cash or securities equal to a varying specified percentage of the contract amount. This amount is known as initial margin. The margin deposit is intended to ensure completion of the contract (delivery or acceptance of the underlying security) if it is not terminated prior to the specified delivery date. A margin deposit does not constitute a margin transaction for purposes of the fund’s investment restrictions. Minimum initial margin requirements are established by the futures exchanges and may be revised.
In addition, brokers may establish margin deposit requirements that are higher than the exchange minimums. Cash held in the margin accounts generally is not income-producing. However, coupon-bearing securities, such as Treasury bills and bonds, held in margin accounts generally will earn income. Subsequent payments to and from the broker, called variation margin, will be made on a daily basis as the price of the underlying security or index fluctuates, making the future more or less valuable, a process known as marking the contract to market. Changes in variation margin are recorded by the fund as unrealized gains or losses. At any time prior to expiration of the future, the fund may elect to close the position by taking an opposite position. A final determination of variation margin is then made; additional cash is required to be paid by or released to the fund, and the fund realizes a loss or gain.
By buying a put option, a fund obtains the right (but not the obligation) to sell the instrument underlying the option at a fixed strike price and in return a fund pays the current market price for the option (known as the option premium). A fund may terminate its position in a put option it has purchased by allowing it to expire, by exercising the option or by entering into an offsetting transaction, if a liquid market exists. If the option is allowed to expire, a fund will lose the entire premium it paid. If a fund exercises a put option on a security, it will sell the instrument underlying the option at the strike price. The buyer of a typical put option can expect to realize a gain if the value of the underlying instrument falls substantially. However, if the price of the instrument underlying the option does not fall enough to offset the cost of purchasing the option, a put buyer can expect to suffer a loss limited to the amount of the premium paid, plus related transaction costs.
The features of call options are essentially the same as those of put options, except that the buyer of a call option obtains the right to purchase, rather than sell, the instrument underlying the option at the option’s strike price. The buyer of a typical call option can expect to realize a gain if the value of the underlying instrument increases substantially and can expect to suffer a loss if security prices do not rise sufficiently to offset the cost of the option.
When a fund writes a put option, it takes the opposite side of the transaction from the option’s buyer. In return for the receipt of the premium, a fund assumes the obligation to pay the strike price for the instrument underlying the option if the other party to the option chooses to exercise it. A fund may seek to terminate its position in a put option it writes before exercise by purchasing an offsetting option in the market at its current price. Otherwise, a fund must continue to be prepared to pay the strike price while the option is outstanding, regardless of price changes, and must continue to post margin as discussed below. If the price of the underlying instrument rises, a put writer would generally realize as profit the premium it received. If the price of the underlying instrument remains the same over time, it is likely that the writer will also profit, because it should be able to close out the option at a lower price. If the price of the underlying instrument falls, the put writer would expect to suffer a loss.
A fund writing a call option is obligated to sell or deliver the option’s underlying instrument in return for the strike price upon exercise of the option. Writing calls generally is a profitable strategy if the price of the underlying instrument remains the same or falls. A call writer offsets part of the effect of a price decline by receipt of the option premium, but gives up some ability to

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participate in security price increases. The writer of an exchange traded put or call option on a security, an index of securities or a futures contract is required to deposit cash or securities or a letter of credit as margin and to make mark to market payments of variation margin as the position becomes unprofitable.
Risks Related to Futures and Options Transactions
Futures and options prices can be volatile, and trading in these markets involves certain risks. If the portfolio managers apply a hedge at an inappropriate time or judge interest rate or equity market trends incorrectly, futures and options strategies may lower a fund’s return.
A fund could suffer losses if it is unable to close out its position because of an illiquid secondary market. Futures contracts may be closed out only on an exchange that provides a secondary market for these contracts, and there is no assurance that a liquid secondary market will exist for any particular futures contract at any particular time. Consequently, it may not be possible to close a futures position when the portfolio managers consider it appropriate or desirable to do so. In the event of adverse price movements, a fund would be required to continue making daily cash payments to maintain its required margin. If the fund had insufficient cash, it might have to sell portfolio securities to meet daily margin requirements at a time when the portfolio managers would not otherwise do so. In addition, a fund may be required to deliver or take delivery of instruments underlying futures contracts it holds. The portfolio managers will seek to minimize these risks by limiting the contracts entered into on behalf of the funds to those traded on national futures exchanges and for which there appears to be a liquid secondary market.
A fund could suffer losses if the prices of its futures and options positions were poorly correlated with its other investments, or if securities underlying futures contracts purchased by a fund had different maturities than those of the portfolio securities being hedged. Such imperfect correlation may give rise to circumstances in which a fund loses money on a futures contract at the same time that it experiences a decline in the value of its hedged portfolio securities. A fund also could lose margin payments it has deposited with a margin broker, if, for example, the broker became bankrupt.
Most futures exchanges limit the amount of fluctuation permitted in futures contract prices during a single trading day. The daily limit establishes the maximum amount that the price of a futures contract may vary either up or down from the previous day’s settlement price at the end of the trading session. Once the daily limit has been reached in a particular type of contract, no trades may be made on that day at a price beyond the limit. However, the daily limit governs only price movement during a particular trading day and, therefore, does not limit potential losses. In addition, the daily limit may prevent liquidation of unfavorable positions. Futures contract prices have occasionally moved to the daily limit for several consecutive trading days with little or no trading, thereby preventing prompt liquidation of futures positions and subjecting some futures traders to substantial losses.
Options on Futures
By purchasing an option on a futures contract, a fund obtains the right, but not the obligation, to sell the futures contract (a put option) or to buy the contract (a call option) at a fixed strike price. A fund can terminate its position in a put option by allowing it to expire or by exercising the option. If the option is exercised, the fund completes the sale of the underlying security at the strike price. Purchasing an option on a futures contract does not require a fund to make margin payments unless the option is exercised.
Although they do not currently intend to do so, the funds may write (or sell) call options that obligate them to sell (or deliver) the option’s underlying instrument upon exercise of the option. While the receipt of option premiums would mitigate the effects of price declines, the funds would give up some ability to participate in a price increase on the underlying security. If a fund were to engage in options transactions, it would own the futures contract at the time a call was written and would keep the contract open until the obligation to deliver it expired.
Restrictions on the Use of Futures Contracts and Options
Each fund may enter into futures contracts, options, options on futures contracts, or swap agreements as permitted by its investment policies and the CFTC rules. The advisor has claimed an exclusion from the definition of the term “commodity pool operator” under the Commodity Exchange Act and, therefore, the advisor is not subject to registration or regulation as a commodity pool operator under that Act with respect to its provision of services to each fund.
The CFTC recently adopted certain rule amendments that may impose additional limits on the ability of a fund to invest in futures contracts, options on futures, swaps, and certain other commodity interests if its investment advisor does not register with the CTFC as a “commodity pool operator” with respect to such fund. It is expected that the funds will be able to execute their investment strategies within the limits adopted by the CTFC’s rules. As a result, the advisor does not intend to register with the CTFC as a commodity pool operator on behalf of any of the funds. In the event that one of the funds engages in transactions that necessitate future registration with the CFTC, the advisor will register as a commodity pool operator and comply with applicable regulations with respect to that fund.
To the extent required by law, each fund will segregate cash, cash equivalents or other appropriate liquid securities on its records in an amount sufficient to cover its obligations under the futures contracts, options and swap agreements.

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Inflation-linked Securities
The American Century Diversified Corporate Bond ETF may purchase inflation-linked securities issued by the U.S. Treasury, U.S. government agencies and instrumentalities other than the U.S. Treasury, and entities other than the U.S. Treasury or U.S. government agencies and instrumentalities.
Inflation-linked securities are designed to offer a return linked to inflation, thereby protecting future purchasing power of the money invested in them. However, inflation-linked securities provide this protected return only if held to maturity. In addition, inflation-linked securities may not trade at par value. Real interest rates (the market rate of interest less the anticipated rate of inflation) change over time as a result of many factors, such as what investors are demanding as a true value for money. When real rates do change, inflation-linked securities prices will be more sensitive to these changes than conventional bonds, because these securities were sold originally based upon a real interest rate that is no longer prevailing. Should market expectations for real interest rates rise, the price of inflation-linked securities and the share price of the fund holding these securities will fall. Investors in the fund should be prepared to accept not only this share price volatility but also the possible adverse tax consequences it may cause.
An investment in securities featuring inflation-indexed principal and/or interest involves factors not associated with more traditional fixed-principal securities. Such factors include the possibility that the inflation index may be subject to significant changes, that changes in the index may or may not correlate to changes in interest rates generally or changes in other indices, or that the resulting interest may be greater or less than that payable on other securities of similar maturities. In the event of sustained deflation, it is possible that the amount of semiannual interest payments, the inflation-indexed principal of the security or the value of the stripped components will decrease. If any of these possibilities are realized, a fund’s net asset value could be negatively affected.
Inflation-linked Treasury Securities
Inflation-linked U.S. Treasury securities are U.S. Treasury securities with a final value and interest payment stream linked to the inflation rate. Inflation-linked U.S. Treasury securities may be issued in either note or bond form. Inflation-linked U.S. Treasury notes have maturities of at least one year, but not more than 10 years. Inflation-linked U.S. Treasury bonds have maturities of more than 10 years.
Inflation-linked U.S. Treasury securities may be attractive to investors seeking an investment backed by the full faith and credit of the U.S. government that provides a return in excess of the rate of inflation. These securities were first sold in the U.S. market in January 1997. Inflation-linked U.S. Treasury securities are auctioned and issued on a quarterly basis.
Structure and Inflation Index - The principal value of inflation-linked U.S. Treasury securities will be adjusted to reflect changes in the level of inflation. The index for measuring the inflation rate for inflation-linked U.S. Treasury securities is the non-seasonally adjusted U.S. City Average All Items Consumer Price Index for All Urban Consumers (Consumer Price Index) published monthly by the U.S. Department of Labor’s Bureau of Labor Statistics.
Semiannual coupon interest payments are made at a fixed percentage of the inflation-linked principal value. The coupon rate for the semiannual interest rate of each issuance of inflation-linked U.S. Treasury securities is determined at the time the securities are sold to the public (i.e., by competitive bids in the auction). The coupon rate will likely reflect real yields available in the U.S. Treasury market; real yields are the prevailing yields on U.S. Treasury securities with similar maturities, less then-prevailing inflation expectations. While a reduction in inflation will cause a reduction in the interest payment made on the securities, the repayment of principal at the maturity of the security is guaranteed by the U.S. Treasury to be no less than the original face or par amount of the security at the time of issuance.
Indexing Methodology - The principal value of inflation-linked U.S. Treasury securities will be indexed, or adjusted, to account for changes in the Consumer Price Index. Semiannual coupon interest payment amounts will be determined by multiplying the inflation-linked principal amount by one-half the stated rate of interest on each interest payment date.
Taxation - The taxation of inflation-linked U.S. Treasury securities is similar to the taxation of conventional bonds. Both interest payments and the difference between original principal and the inflation-indexed principal will be treated as interest income subject to taxation. Interest payments are taxable when received or accrued. The inflation adjustment to the principal is subject to tax in the year the adjustment is made, not at maturity of the security when the cash from the repayment of principal is received. If an upward adjustment has been made, investors in non-tax-deferred accounts will pay taxes on this amount currently. Decreases in the indexed principal can be deducted only from current or previous interest payments reported as income.
Inflation-linked U.S. Treasury securities therefore have a potential cash flow mismatch to an investor, because investors must pay taxes on the inflation-indexed principal before the repayment of principal is received. It is possible that, particularly for high income tax bracket investors, inflation-linked U.S. Treasury securities would not generate enough cash in a given year to cover the tax liability they could create. This is similar to the current tax treatment for zero-coupon bonds and other discount securities. If inflation-linked U.S. Treasury securities are sold prior to maturity, capital losses or gains are realized in the same manner as traditional bonds.

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Investors in the fund will receive dividends that represent both the interest payments and the principal adjustments of the inflation-linked securities held in the fund’s portfolio. An investment in the fund may, therefore, be a means to avoid the cash flow mismatch associated with a direct investment in inflation-linked securities. For more information about taxes and their effect on you as an investor in the fund, see Taxes, page 45 .
U.S. Government Agencies
A number of U.S. government agencies and instrumentalities other than the U.S. Treasury may issue inflation-linked securities. Some U.S. government agencies have issued inflation-linked securities whose design mirrors that of the inflation-linked U.S. Treasury securities described above.
Other Entities
Entities other than the U.S. Treasury or U.S. government agencies and instrumentalities may issue inflation-linked securities. While some entities have issued inflation-linked securities whose design mirrors that of the inflation-linked U.S. Treasury securities described above, others utilize different structures. For example, the principal value of these securities may be adjusted with reference to the Consumer Price Index, but the semiannual coupon interest payments are made at a fixed percentage of the original issue principal. Alternatively, the principal value may remain fixed, but the coupon interest payments may be adjusted with reference to the Consumer Price Index.
Initial Public Offerings
The funds may invest in initial public offerings (IPOs) of common stock or other equity securities issued by a company. The purchase of securities in an IPO may involve higher transaction costs than those associated with the purchase of securities already traded on exchanges or other established markets. In addition to the risks associated with equity securities generally, IPO securities may be subject to additional risk due to factors such as the absence of a prior public market, unseasoned trading and speculation, a potentially small number of securities available for trading, limited information about the issuer and other factors. These factors may cause IPO shares to be volatile in price. While a fund may hold IPO securities for a period of time, it may sell them in the aftermarket soon after the purchase, which could increase portfolio turnover and lead to increased expenses such as commissions and transaction costs. Investments in IPOs could have a magnified impact (either positive or negative) on performance if a fund’s assets are relatively small. The impact of IPOs on a fund’s performance may tend to diminish as assets grow.
Inverse Floaters
The American Century Diversified Corporate Bond ETF may hold inverse floaters. An inverse floater is a type of derivative instrument that bears an interest rate that moves inversely to market interest rates. As market interest rates rise, the interest rate on inverse floaters goes down, and vice versa. Generally, this is accomplished by expressing the interest rate on the inverse floater as an above-market fixed rate of interest, reduced by an amount determined by reference to a market-based or bond-specific floating interest rate (as well as by any fees associated with administering the inverse floater program).
Inverse floaters may be issued in conjunction with an equal amount of Dutch Auction floating-rate bonds (floaters), or a market-based index may be used to set the interest rate on these securities. A Dutch Auction is an auction system in which the price of the security is gradually lowered until it meets a responsive bid and is sold. Floaters and inverse floaters may be brought to market by (1) a broker-dealer who purchases fixed-rate bonds and places them in a trust, or (2) an issuer seeking to reduce interest expenses by using a floater/inverse floater structure in lieu of fixed-rate bonds.
In the case of a broker-dealer structured offering (where underlying fixed-rate bonds have been placed in a trust), distributions from the underlying bonds are allocated to floater and inverse floater holders in the following manner:
(i)
Floater holders receive interest based on rates set at a six-month interval or at a Dutch Auction, which is typically held every 28 to 35 days. Current and prospective floater holders bid the minimum interest rate that they are willing to accept on the floaters, and the interest rate is set just high enough to ensure that all of the floaters are sold.
(ii)
Inverse floater holders receive all of the interest that remains, if any, on the underlying bonds after floater interest and auction fees are paid. The interest rates on inverse floaters may be significantly reduced, even to zero, if interest rates rise.
Procedures for determining the interest payment on floaters and inverse floaters brought to market directly by the issuer are comparable, although the interest paid on the inverse floaters is based on a presumed coupon rate that would have been required to bring fixed-rate bonds to market at the time the floaters and inverse floaters were issued.
Where inverse floaters are issued in conjunction with floaters, inverse floater holders may be given the right to acquire the underlying security (or to create a fixed-rate bond) by calling an equal amount of corresponding floaters. The underlying security may then be held or sold. However, typically, there are time constraints and other limitations associated with any right to combine interests and claim the underlying security.
Floater holders subject to a Dutch Auction procedure generally do not have the right to put back their interests to the issuer or to a third party. If a Dutch Auction fails, the floater holder may be required to hold its position until the underlying bond matures, during which time interest on the floater is capped at a predetermined rate.

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The secondary market for floaters and inverse floaters may be limited. The market value of inverse floaters tends to be significantly more volatile than fixed-rate bonds.
Investment in Issuers with Limited Operating Histories
The funds may invest a portion of its assets in the equity securities of issuers with limited operating histories. The portfolio managers consider an issuer to have a limited operating history if that issuer has a record of less than three years of continuous operation. The managers will consider periods of capital formation, incubation, consolidations, and research and development in determining whether a particular issuer has a record of three years of continuous operation.
Investments in securities of issuers with limited operating histories may involve greater risks than investments in securities of more mature issuers. By their nature, such issuers present limited operating histories and financial information upon which the managers may base their investment decision on behalf of the funds. In addition, financial and other information regarding these issuers, when available, may be incomplete or inaccurate.
For purposes of this limitation, “issuers” refers to operating companies that issue securities for the purposes of issuing debt or raising capital as a means of financing their ongoing operations. It does not, however, refer to entities, corporate or otherwise, that are created for the express purpose of securitizing obligations or income streams. For example, a fund’s investments in a trust created for the purpose of pooling mortgage obligations or other financial assets would not be subject to the limitation.
Loan Participations
The American Century Diversified Corporate Bond ETF may purchase loan participations, which represent interests in the cash flow generated by commercial loans. Each loan participation requires three parties: a participant (or investor), a lending bank and a borrower. The investor purchases a share in a loan originated by a lending bank, and this participation entitles the investor to a percentage of the principal and interest payments made by the borrower.
Loan participations are attractive because they typically offer higher yields than other money market instruments. However, along with these higher yields come certain risks, not the least of which is the risk that the borrower will be unable to repay the loan. Generally, because the lending bank does not guarantee payment, the investor is directly exposed to risk of default by the borrower. In addition, the investor is not a direct creditor of the borrower. The participation represents an interest in assets owned by the lending bank. If the lending bank becomes insolvent, the investor could be considered an unsecured creditor of the bank instead of the holder of a participating interest in a loan. Because of these risks, the manager must carefully consider the creditworthiness of both the borrower and the lender.
Another concern is liquidity. Because there is no established secondary market for loan participations, a fund’s ability to sell them for cash is limited. Some participation agreements place limitations on the investor’s right to resell the loan participation, even when a buyer can be found.
Loan Participation Notes
The American Century Diversified Corporate Bond ETF may invest in loan participation notes. In terms of their functioning and investment risk, loan participation notes (“LPNs”) are comparable to an investment in “normal” bonds. In return for the investor’s commitment of capital, the issuer makes regular interest payments and, at maturity or in accordance with an agreed upon amortization schedule, the note is repaid at par.
However, in contrast to “normal” bonds, there are three parties involved in the issuance of an LPN. The legal issuer, typically a bankruptcy-remote, limited purpose entity, issues notes to investors and uses the proceeds received from investors to make loans to the borrower-with each loan generally having substantially identical payment terms to the related note issued by the issuer. The borrower is typically an operating company, and the issuer’s obligations under a note are typically limited to the extent of any capital repayments and interest payments made by the borrower under the related loan. Accordingly, the investor generally assumes the credit risk of the underlying borrower. The loan participation note structure is generally used to provide the borrower more efficient financing in the capital markets than the borrower would be able to obtain if it issued notes directly.
In the event of a default by the borrower of an LPN, the fund may experience delays in receiving payments of interest and principal while the note issuer enforces and liquidates the underlying collateral, and there is no guarantee that the underlying collateral will cover the principal and interest owed to the fund under the LPN.
LPNs are generally subject to liquidity risk. Even though an LPN may be traded on an exchange there can be no assurance that a liquid market will develop for the LPNs, that holders of the LPNs will be able to sell their LPNs, or that such holders will be able to sell their LPNs for a price that reflects their value.
Depending on the creditworthiness of the underlying borrower, LPNs may be subject to the risk of investing in high-yield securities. Additionally, LPNs are generally utilized by foreign borrowers and therefore may be subject to the risk of investing in foreign securities and emerging market risk. Such foreign risk could include interest payments being subject to withholding tax.

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Loans of Portfolio Securities
In order to realize additional income, a fund may lend its portfolio securities. Such loans may not exceed one-third of the fund’s total assets valued at market, however, this limitation does not apply to purchases of debt securities in accordance with the fund’s investment objectives, policies and limitations, or to repurchase agreements with respect to portfolio securities.
Cash received from the borrower as collateral through loan transactions may be invested in other eligible securities. Investing this cash subjects that investment to market appreciation or depreciation. If a borrower defaults on a securities loan because of insolvency or other reasons, the lending fund could experience delays or costs in recovering the securities it loaned; if the value of the loaned securities increased over the value of the collateral, the fund could suffer a loss. To minimize the risk of default on securities loans, the advisor adheres to guidelines prescribed by the Board of Trustees governing lending of securities. These guidelines strictly govern:
the type and amount of collateral that must be received by the fund;
the circumstances under which additions to that collateral must be made by borrowers;
the return to be received by the fund on the loaned securities;
the limitations on the percentage of fund assets on loan; and
the credit standards applied in evaluating potential borrowers of portfolio securities.
In addition, the guidelines require that the fund have the option to terminate any loan of a portfolio security at any time and set requirements for recovery of securities from borrowers.
Mortgage-Related Securities
To the extent permitted by its investment objective and policies, the American Century Diversified Corporate Bond ETF may invest in mortgage-related securities.
Background
A mortgage-backed security represents an ownership interest in a pool of mortgage loans. The loans are made by financial institutions to finance home and other real estate purchases. As the loans are repaid, investors receive payments of both interest and principal.
Like fixed-income securities such as U.S. Treasury bonds, mortgage-backed securities pay a stated rate of interest during the life of the security. However, unlike a bond, which returns principal to the investor in one lump sum at maturity, mortgage-backed securities return principal to the investor in increments during the life of the security.
Because the timing and speed of principal repayments vary, the cash flow on mortgage-backed securities is irregular. If mortgage holders sell their homes, refinance their loans, prepay their mortgages or default on their loans, the principal is distributed pro rata to investors.
As with other fixed-income securities, the prices of mortgage-backed securities fluctuate in response to changing interest rates; when interest rates fall, the prices of mortgage-backed securities rise, and vice versa. Changing interest rates have additional significance for mortgage-backed securities investors, however, because they influence prepayment rates (the rates at which mortgage holders prepay their mortgages), which in turn affect the yields on mortgage-backed securities. When interest rates decline, prepayment rates generally increase. Mortgage holders take advantage of the opportunity to refinance their mortgages at lower rates with lower monthly payments. When interest rates rise, mortgage holders are less inclined to refinance their mortgages. The effect of prepayment activity on yield depends on whether the mortgage-backed security was purchased at a premium or at a discount.
The fund may receive principal sooner than it expected because of accelerated prepayments. Under these circumstances, the fund might have to reinvest returned principal at rates lower than it would have earned if principal payments were made on schedule. Conversely, a mortgage-backed security may exceed its anticipated life if prepayment rates decelerate unexpectedly. Under these circumstances, the fund might miss an opportunity to earn interest at higher prevailing rates.
GNMA Certificates
The Government National Mortgage Association (GNMA) is a wholly owned corporate instrumentality of the United States within the Department of Housing and Urban Development. The National Housing Act of 1934 (Housing Act), as amended, authorizes GNMA to guarantee the timely payment of interest and repayment of principal on certificates that are backed by a pool of mortgage loans insured by the Federal Housing Administration under the Housing Act, or by Title V of the Housing Act of 1949 (FHA Loans), or guaranteed by the Veterans’ Affairs under the Servicemen’s Readjustment Act of 1944 (VA Loans), as amended, or by pools of other eligible mortgage loans. The Housing Act provides that the full faith and credit of the U.S. government is pledged to the payment of all amounts that may be required to be paid under any guarantee. GNMA has unlimited authority to borrow from the U.S. Treasury in order to meet its obligations under this guarantee.
GNMA certificates represent a pro rata interest in one or more pools of the following types of mortgage loans: (a) fixed-rate level payment mortgage loans; (b) fixed-rate graduated payment mortgage loans (GPMs); (c) fixed-rate growing equity mortgage loans

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(GEMs); (d) fixed-rate mortgage loans secured by manufactured (mobile) homes (MHs); (e) mortgage loans on multifamily residential properties under construction (CLCs); (f) mortgage loans on completed multifamily projects (PLCs); (g) fixed-rate mortgage loans that use escrowed funds to reduce the borrower’s monthly payments during the early years of the mortgage loans (buydown mortgage loans); and (h) mortgage loans that provide for payment adjustments based on periodic changes in interest rates or in other payment terms of the mortgage loans.
Recent Events Regarding Fannie Mae and Freddie Mac
Since September 2008, Fannie Mae and Freddie Mac have operated under a conservatorship administered by the Federal Housing Finance Agency (FHFA). In addition, the U.S. Treasury has entered into senior preferred stock purchase agreements (PSPA) to provide additional financing to Fannie Mae and Freddie Mac. Three amendments have been made to the original agreement and PSPA, each of which has further strengthened the credit worthiness of these entities. The most recent amendment eliminates the requirement to pay a 10% preferred stock dividend in exchange for a quarterly sweep of net worth. This in turn eliminates any need to borrow from the Treasury to pay dividends and was intended to strengthen the financial commitment to these enterprises.
The future status and role of Fannie Mae or Freddie Mac could be impacted by, among other things, the actions taken and restrictions placed on Fannie Mae or Freddie Mac by the FHFA in its role as conservator, the restrictions placed on Fannie Mae’s or Freddie Mac’s operations and activities under the senior preferred stock purchase agreements, market responses to developments at Fannie Mae or Freddie Mac, and future legislative, regulatory, or legal action that alters the operations, ownership, structure and/or mission of Fannie Mae or Freddie Mac, each of which may, in turn, impact the value of, and cash flows on, any securities guaranteed by Fannie Mae and Freddie Mac.
Fannie Mae Certificates
The Federal National Mortgage Association (FNMA or Fannie Mae) is a federally chartered and privately owned corporation established under the Federal National Mortgage Association Charter Act. Fannie Mae was originally established in 1938 as a U.S. government agency designed to provide supplemental liquidity to the mortgage market and was reorganized as a stockholder-owned and privately managed corporation by legislation enacted in 1968. Fannie Mae acquires capital from investors who would not ordinarily invest in mortgage loans directly and thereby expands the total amount of funds available for housing. This money is used to buy home mortgage loans from local lenders, replenishing the supply of capital available for mortgage lending.
Fannie Mae certificates represent a pro rata interest in one or more pools of FHA Loans, VA Loans, or, most commonly, conventional mortgage loans (i.e., mortgage loans that are not insured or guaranteed by a government agency) of the following types: (a) fixed-rate level payment mortgage loans; (b) fixed-rate growing equity mortgage loans; (c) fixed-rate graduated payment mortgage loans; (d) adjustable-rate mortgage loans; and (e) fixed-rate mortgage loans secured by multifamily projects.
Fannie Mae certificates entitle the registered holder to receive amounts representing a pro rata interest in scheduled principal and interest payments (at the certificate’s pass-through rate, which is net of any servicing and guarantee fees on the underlying mortgage loans), any principal prepayments, and a proportionate interest in the full principal amount of any foreclosed or otherwise liquidated mortgage loan. The full and timely payment of interest and repayment of principal on each Fannie Mae certificate is guaranteed by Fannie Mae; this guarantee is not backed by the full faith and credit of the U.S. government.
Freddie Mac Certificates
The Federal Home Loan Mortgage Corporation (FHLMC or Freddie Mac) is a corporate instrumentality of the United States created pursuant to the Emergency Home Finance Act of 1970 (FHLMC Act), as amended. Freddie Mac was established primarily for the purpose of increasing the availability of mortgage credit. Its principal activity consists of purchasing first-lien conventional residential mortgage loans (and participation interests in such mortgage loans) and reselling these loans in the form of mortgage-backed securities, primarily Freddie Mac certificates.
Freddie Mac certificates represent a pro rata interest in a group of mortgage loans (a Freddie Mac certificate group) purchased by Freddie Mac. The mortgage loans underlying Freddie Mac certificates consist of fixed- or adjustable-rate mortgage loans with original terms to maturity of between 10 and 30 years, substantially all of which are secured by first-liens on one- to four-family residential properties or multifamily projects. Each mortgage loan must meet standards set forth in the FHLMC Act. A Freddie Mac certificate group may include whole loans, participation interests in whole loans, undivided interests in whole loans, and participations composing another Freddie Mac certificate group.
Freddie Mac guarantees to each registered holder of a Freddie Mac certificate the timely payment of interest at the rate provided for by the certificate. Freddie Mac also guarantees ultimate collection of all principal on the related mortgage loans, without any offset or deduction, but generally does not guarantee the timely repayment of principal. Freddie Mac may remit principal at any time after default on an underlying mortgage loan, but no later than 30 days following (a) foreclosure sale, (b) payment of a claim by any mortgage insurer, or (c) the expiration of any right of redemption, whichever occurs later, and in any event no later than one year after demand has been made upon the mortgager for accelerated payment of principal. Obligations guaranteed by Freddie Mac are not backed by the full faith and credit pledge of the U.S. government.

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Collateralized Mortgage Obligations (CMOs)
A CMO is a multiclass bond backed by a pool of mortgage pass-through certificates or mortgage loans. CMOs may be collateralized by (a) GNMA, Fannie Mae or Freddie Mac pass-through certificates; (b) unsecured mortgage loans insured by the Federal Housing Administration or guaranteed by the Department of Veterans’ Affairs; (c) unsecuritized conventional mortgages; or (d) any combination thereof.
In structuring a CMO, an issuer distributes cash flow from the underlying collateral over a series of classes called tranches. Each CMO is a set of two or more tranches, with average lives and cash flow patterns designed to meet specific investment objectives. The average life expectancies of the different tranches in a four-part deal, for example, might be two, five, seven and 20 years.
As payments on the underlying mortgage loans are collected, the CMO issuer pays the coupon rate of interest to the bondholders in each tranche. At the outset, scheduled and unscheduled principal payments go to investors in the first tranches. Investors in later tranches do not begin receiving principal payments until the prior tranches are paid off. This basic type of CMO is known as a sequential pay or plain vanilla CMO.
Some CMOs are structured so that the prepayment or market risks are transferred from one tranche to another. Prepayment stability is improved in some tranches if other tranches absorb more prepayment variability.
The final tranche of a CMO often takes the form of a Z-bond, also known as an accrual bond or accretion bond. Holders of these securities receive no cash until the earlier tranches are paid in full. During the period that the other tranches are outstanding, periodic interest payments are added to the initial face amount of the Z-bond but are not paid to investors. When the prior tranches are retired, the Z-bond receives coupon payments on its higher principal balance plus any principal prepayments from the underlying mortgage loans. The existence of a Z-bond tranche helps stabilize cash flow patterns in the other tranches. In a changing interest rate environment, however, the value of the Z-bond tends to be more volatile.
As CMOs have evolved, some classes of CMO bonds have become more prevalent. The planned amortization class (PAC) and targeted amortization class (TAC), for example, were designed to reduce prepayment risk by establishing a sinking-fund structure. PAC and TAC bonds assure to varying degrees that investors will receive payments over a predetermined period under various prepayment scenarios. Although PAC and TAC bonds are similar, PAC bonds are better able to provide stable cash flows under various prepayment scenarios than TAC bonds because of the order in which these tranches are paid.
The existence of a PAC or TAC tranche can create higher levels of risk for other tranches in the CMO because the stability of the PAC or TAC tranche is achieved by creating at least one other tranche-known as a companion bond, support or non-PAC bond-that absorbs the variability of principal cash flows. Because companion bonds have a high degree of average life variability, they generally pay a higher yield. A TAC bond can have some of the prepayment variability of a companion bond if there is also a PAC bond in the CMO issue.
Floating-rate CMO tranches (floaters) pay a variable rate of interest that is usually tied to the London Interbank Offered Rate (LIBOR). Institutional investors with short-term liabilities, such as commercial banks, often find floating-rate CMOs attractive investments. Super floaters (which float a certain percentage above LIBOR) and inverse floaters (which float inversely to LIBOR) are variations on the floater structure that have highly variable cash flows.
Stripped Mortgage-Backed Securities
Stripped mortgage-backed securities are created by segregating the cash flows from underlying mortgage loans or mortgage securities to create two or more new securities, each with a specified percentage of the underlying security’s principal or interest payments. Mortgage-backed securities may be partially stripped so that each investor class receives some interest and some principal. When securities are completely stripped, however, all of the interest is distributed to holders of one type of security, known as an interest-only security, or IO, and all of the principal is distributed to holders of another type of security known as a principal-only security, or PO. Strips can be created in a pass-through structure or as tranches of a CMO.
The market values of IOs and POs are very sensitive to interest rate and prepayment rate fluctuations. POs, for example, increase (or decrease) in value as interest rates decline (or rise). The price behavior of these securities also depends on whether the mortgage collateral was purchased at a premium or discount to its par value. Prepayments on discount coupon POs generally are much lower than prepayments on premium coupon POs. IOs may be used to hedge a fund’s other investments because prepayments cause the value of an IO strip to move in the opposite direction from other mortgage-backed securities.
Commercial Mortgage-Backed Securities (CMBS)
CMBS are securities created from a pool of commercial mortgage loans, such as loans for hotels, shopping centers, office buildings, apartment buildings, and the like. Interest and principal payments from these loans are passed on to the investor according to a particular schedule of payments. They may be issued by U.S. government agencies or by private issuers. The credit quality of CMBS depends primarily on the quality of the underlying loans and on the structure of the particular deal. Generally, deals are structured with senior and subordinate classes. Multiple classes may permit the issuance of securities with payment terms, interest rates, or other characteristics differing both from those of each other and those of the underlying assets. Examples include classes having characteristics such as floating interest rates or scheduled amortization of principal. Rating agencies rate the individual classes of the deal based on the degree of seniority or subordination of a particular class and other factors. The value of

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these securities may change because of actual or perceived changes in the creditworthiness of individual borrowers, their tenants, the servicing agents, or the general state of commercial real estate and other factors.
CMBS may be partially stripped so that each investor class receives some interest and some principal. When securities are completely stripped, however, all of the interest is distributed to holders of one type of security, known as an interest-only security (IO), and all of the principal is distributed to holders of another type of security known as a principal-only security (PO). The American Century Diversified Corporate Bond ETF is permitted to invest in IO classes of CMBS. As interest rates rise and fall, the value of IOs tends to move in the same direction as interest rates. The cash flows and yields on IO classes are extremely sensitive to the rate of principal payments (including prepayments) on the related underlying mortgage assets. In the cases of IOs, prepayments affect the amount of cash flows provided to the investor. If the underlying mortgage assets experience greater than anticipated prepayments of principal, an investor may fail to fully recoup its initial investment in an IO class of a stripped mortgage-backed security, even if the IO class is rated AAA or Aaa or is derived from a full faith and credit obligation. However, because commercial mortgages are often locked out from prepayment, or have high prepayment penalties or a defeasance mechanism, the prepayment risk associated with a CMBS IO class is generally less than that of a residential IO.
Adjustable Rate Mortgage Securities
Adjustable rate mortgage securities (ARMs) have interest rates that reset at periodic intervals. Acquiring ARMs permits the American Century Diversified Corporate Bond ETF to participate in increases in prevailing current interest rates through periodic adjustments in the coupons of mortgages underlying the pool on which ARMs are based. In addition, when prepayments of principal are made on the underlying mortgages during periods of rising interest rates, a fund can reinvest the proceeds of such prepayments at rates higher than those at which they were previously invested. Mortgages underlying most ARMs, however, have limits on the allowable annual or lifetime increases that can be made in the interest rate that the mortgagor pays. Therefore, if current interest rates rise above such limits over the period of the limitation, a fund holding an ARM does not benefit from further increases in interest rates. Moreover, when interest rates are in excess of coupon rates (i.e., the rates being paid by mortgagors) of the mortgages, ARMs behave more like fixed-income securities and less like adjustable rate securities and are subject to the risks associated with fixed-income securities. In addition, during periods of rising interest rates, increases in the coupon rate of adjustable rate mortgages generally lag current market interest rates slightly, thereby creating the potential for capital depreciation on such securities.
Mortgage Dollar Rolls
The American Century Diversified Corporate Bond ETF may enter into mortgage dollar rolls in which a fund sells mortgage-backed securities to financial institutions for delivery in the current month and simultaneously contracts to repurchase similar securities on a specified future date. During the period between the sale and repurchase (the “roll period”), the fund forgoes principal and interest paid on the mortgage-backed securities. The fund is compensated by the difference between the current sales price and the forward price for the future purchase (often referred to as the “drop”), as well as by the interest earned on the cash proceeds of the initial sale. The fund will use the proceeds generated from the transaction to invest in high-quality, short duration investments, which may enhance the fund’s current yield and total return. Such investments may have a leveraging effect, increasing the volatility of the fund.
For each mortgage dollar roll transaction, the fund will cover the roll by segregating on its books an offsetting cash position or a position of liquid securities of equivalent value. The portfolio managers will monitor the value of such securities to determine that the value equals or exceeds the mortgage dollar roll contract price.
The fund could suffer a loss if the contracting party fails to perform the future transaction and the fund is therefore unable to buy back the mortgage-backed securities it initially sold. The fund also takes the risk that the mortgage-backed securities that it repurchases at a later date will have less favorable market characteristics than the securities originally sold.
Municipal Obligations
The American Century Diversified Corporate Bond ETF may invest in tax-exempt or taxable municipal obligations, which are generally issued by state and local governments or government entities. Interest payments from municipal obligations are generally exempt from federal income tax. Interest payments from certain municipal obligations, however, are subject to federal income tax because of the degree of non-government involvement in the transaction or because federal tax code limitations on the issuance of tax-exempt bonds that benefit private entities have been exceeded. Some typical examples of these taxable municipal obligations include industrial revenue bonds and economic development bonds issued by state or local governments to aid private enterprise. The interest on a taxable municipal bond is often exempt from state taxation in the issuing state. The fund does not expect to be eligible to pass through to shareholders the tax-exempt character of interest on municipal obligations.
Municipal Bonds
The American Century Diversified Corporate Bond ETF may invest in municipal bonds, which generally have maturities of more than one year when issued and are designed to meet longer-term capital needs. These securities have two principal classifications: general obligation bonds and revenue bonds.

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General Obligation (GO) bonds are issued by states, counties, cities, towns and regional districts to fund a variety of public projects, including construction of and improvements to schools, highways, and water and sewer systems. GO bonds are backed by the issuer’s full faith and credit pledge based on its ability to levy taxes for the timely payment of interest and repayment of principal, although such levies may be constitutionally or statutorily limited as to rate or amount.
Revenue bonds are not backed by an issuer’s taxing authority; rather, interest and principal are secured by the net revenues from a project or facility. Revenue bonds are issued to finance a variety of capital projects, including construction or refurbishment of utility and waste disposal systems, highways, bridges, tunnels, air and seaport facilities, schools and hospitals.
Industrial Development Bonds (IDBs), a type of revenue bond, are issued by or on behalf of public authorities to finance privately operated facilities. These bonds are used to finance business, manufacturing, housing, athletic and pollution control projects, as well as public facilities such as mass transit systems, air and seaport facilities and parking garages. Payment of interest and repayment of principal on an IDB depend solely on the ability of the facility’s operator to meet financial obligations and on the pledge, if any, of the real or personal property financed. The interest earned on IDBs may be subject to the federal alternative minimum tax.
Some longer-term municipal bonds allow an investor to “put” or sell the security at a specified time and price to the issuer or other “put provider.” If a put provider fails to honor its commitment to purchase the security, the fund may have to treat the security’s final maturity as its effective maturity, lengthening the fund’s weighted average maturity and increasing the volatility of the fund.
Municipal Notes
The American Century Diversified Corporate Bond ETF may invest in municipal notes, which are issued by state and local governments or government entities to provide short-term capital or to meet cash flow needs.
Tax Anticipation Notes (TANs) are issued in anticipation of seasonal tax revenues, such as ad valorem property, income, sales, use and business taxes, and are payable from these future taxes. TANs usually are general obligations of the issuer. General obligations are backed by the issuer’s full faith and credit pledge based on its ability to levy taxes for the timely payment of interest and repayment of principal, although such levies may be constitutionally or statutorily limited as to rate or amount.
Revenue Anticipation Notes (RANs) are issued with the expectation that receipt of future revenues, such as federal revenue sharing or state aid payments, will be used to repay the notes. Typically, these notes also constitute general obligations of the issuer.
Bond Anticipation Notes (BANs) are issued to provide interim financing until long-term financing can be arranged. In most cases, the long-term bonds provide the money for repayment of the notes.
Revenue anticipation warrants, or reimbursement warrants, are issued to meet the cash flow needs of state governments at the end of a fiscal year and in the early weeks of the following fiscal year. These warrants are payable from unapplied money in the state’s General Fund, including the proceeds of RANs issued following enactment of a state budget or the proceeds of refunding warrants issued by the state.
Other Investment Companies
Each of the funds may invest in other investment companies, such as closed-end investment companies, unit investment trusts, other ETFs and other open-end investment companies, provided that the investment is consistent with the fund’s investment policies and restrictions. Under the Investment Company Act, a fund’s investment in such securities, subject to certain exceptions, currently is limited to
3% of the total voting stock of any one investment company;
5% of the fund’s total assets with respect to any one investment company; and
10% of a fund’s total assets in the aggregate.
A fund’s investments in other investment companies may include money market funds managed by the advisor. Investments in money market funds are not subject to the percentage limitations set forth above.
Such purchases will be made in the open market where no commission or profit to a sponsor or dealer results from the purchase other than the customary brokers’ commissions. As a shareholder of another investment company, a fund would bear, along with other shareholders, its pro rata portion of the other investment company’s expenses, including advisory fees. These expenses would be in addition to the management fee that each fund bears directly in connection with its own operations.
ETFs are a type of fund bought and sold on a securities exchange. An ETF trades like common stock and usually represents a fixed portfolio of securities designed to track the performance and dividend yield of a particular domestic or foreign market index. A fund may purchase an ETF to temporarily gain exposure to a portion of the U.S. or a foreign market while awaiting purchase of underlying securities. The risks of owning an ETF generally reflect the risks of owning the underlying securities they are designed to track, although the lack of liquidity on an ETF could result in it being more volatile and the market price for the ETF may be higher than or lower than the ETF’s net asset value. Additionally, ETFs have management fees, which increase their cost.

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Repurchase Agreements
Each fund may invest in repurchase agreements when they present an attractive short-term return on cash that is not otherwise committed to the purchase of securities pursuant to the investment policies of that fund.
A repurchase agreement occurs when, at the time a fund purchases an interest-bearing obligation, the seller (a bank or a broker-dealer registered under the Securities Exchange Act of 1934) agrees to purchase it on a specified date in the future at an agreed-upon price. The repurchase price reflects an agreed-upon interest rate during the time the fund’s money is invested in the security.
Because the security purchased constitutes collateral for the repurchase obligation, a repurchase agreement can be considered a loan collateralized by the security purchased. The fund’s risk is the seller’s ability to pay the agreed-upon repurchase price on the repurchase date. If the seller defaults, the fund may incur costs in disposing of the collateral, which would reduce the amount realized. If the seller seeks relief under the bankruptcy laws, the disposition of the collateral may be delayed or limited. To the extent the value of the security decreases, the fund could experience a loss.
The funds will limit repurchase agreement transactions to securities issued by the U.S. government and its agencies and instrumentalities, and will enter into such transactions with those banks and securities dealers who are deemed creditworthy by the advisor.
Repurchase agreements maturing in more than seven days would count toward a fund’s 15% limit on illiquid securities.
Restricted and Illiquid Securities
The funds may, from time to time, purchase restricted or illiquid securities, including Rule 144A securities, when they present attractive investment opportunities that otherwise meet the funds’ criteria for selection. Restricted securities include securities that cannot be sold to the public without registration under the 1933 Act or the availability of an exemption from registration, or that are “not readily marketable” because they are subject to other legal or contractual delays in or restrictions on resale. Rule 144A securities are securities that are privately placed with and traded among qualified institutional investors rather than the general public. Although Rule 144A securities are considered restricted securities, they are not necessarily illiquid.
With respect to securities eligible for resale under Rule 144A, the staff of the SEC has taken the position that the liquidity of such securities in the portfolio of a fund offering redeemable securities is a question of fact for the Board of Trustees to determine, based upon a consideration of the readily available trading markets and the review of any contractual restrictions. Accordingly, the Board of Trustees is responsible for developing and establishing the guidelines and procedures for determining the liquidity of Rule 144A securities. As allowed by Rule 144A, the Board of Trustees has delegated the day-to-day function of determining the liquidity of Rule 144A securities to the advisor. The board retains the responsibility to monitor the implementation of the guidelines and procedures it has adopted.
Because the secondary market for restricted securities is generally limited to certain qualified institutional investors, the liquidity of such securities may be limited accordingly and a fund may, from time to time, hold a Rule 144A or other security that is illiquid. In such an event, the portfolio managers will consider appropriate remedies to minimize the effect on that fund’s liquidity. Each of the funds may invest no more than 15% of the value of its assets in illiquid securities.
Secondary Listings Risk
A fund’s shares may be listed or traded on U.S. and non-U.S. stock exchanges other than the U.S. stock exchange where the fund’s primary listing is maintained. There can be no assurance that a fund’s shares will continue to trade on any such stock exchange or in any market or that the fund’s shares will continue to meet the requirements for listing or trading on any exchange or in any market. The fund’s shares may be less actively traded in certain markets than others, and investors are subject to the execution and settlement risks and market standards of the market where they or their broker direct their trades for execution. Certain information available to investors who trade fund shares on a U.S. stock exchange during regular U.S. market hours may not be available to investors who trade in other markets, which may result in secondary market prices in such markets being less efficient.
Short Sales
Each of the funds may engage in short selling. A fund engages in short selling when it sells a security it does not own. To sell a security short, a fund must borrow the security from someone else to deliver it to the buyer. That fund then replaces the borrowed security by purchasing it at the market price at or before the time of replacement. Until it replaces the security, the fund repays the person that lent it the security for any interest or dividends that may have been paid or accrued during the period of the loan. Each fund may engage in short sales for cash management purposes only if, at the time of the short sale, the fund owns or has the right to acquire securities equivalent in kind and amount to the securities being sold short.
In a short sale, the seller does not immediately deliver the securities sold and is said to have a short position in those securities until delivery occurs. To make delivery to the purchaser, the executing broker borrows the securities being sold short on behalf of the seller. While the short position is maintained, the seller collateralizes its obligation to deliver the securities sold short in an amount equal to the proceeds of the short sale plus an additional margin amount established by the Board of Governors of the Federal Reserve. If a fund engages in a short sale, the fund will segregate cash, cash equivalents or other appropriate liquid securities on its

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records in an amount sufficient to meet the purchase price. There will be additional transaction costs associated with short sales, but the fund will endeavor to offset these costs with income from the investment of the cash proceeds of short sales.
In short sale transactions, a fund’s gain is limited to the price at which it sold the security short; its loss is limited only by the maximum price it must pay to acquire the security less the price at which the security was sold. In theory, losses from short sales may be unlimited. In order to borrow the security, a fund may be required to pay compensation to the lender for securities that are difficult to borrow due to demand or other factors. Short sales also cause a fund to incur brokerage fees and other transaction costs. Therefore, the amount of any gain a fund may receive from a short sale transaction is decreased and the amount of any loss increased by the amount of compensation to the lender, accrued interest or dividends and transaction costs a fund may be required to pay.
There is no guarantee that a fund will be able to close out a short position at any particular time or at a particular price. During the time that a fund is short a security, it is subject to the risk that the lender of the security will terminate the loan at a time when the fund is unable to borrow the same security from another lender. If that occurs, the fund may be “bought in” at the price required to purchase the security needed to close out the short position, which may be a disadvantageous price.
Short-Term Securities
In order to meet anticipated redemptions, anticipated purchases of additional securities for a fund’s portfolio, or, in some cases, for temporary defensive purposes, the funds may invest a portion of their assets in money market and other short-term securities.
Examples of those securities include:
Securities issued or guaranteed by the U.S. government and its agencies and instrumentalities;
Commercial Paper;
Certificates of Deposit and Euro Dollar Certificates of Deposit;
Bankers’ Acceptances;
Short-term notes, bonds, debentures or other debt instruments;
Repurchase agreements; and
Money market funds.
Swap Agreements
The funds may invest in swap agreements, consistent with their investment objective and strategies. A fund may enter into a swap agreement to, for example, attempt to obtain or preserve a particular return or spread at a lower cost than obtaining a return or spread through purchases and/or sales of instruments in other markets; protect against currency fluctuations; attempt to manage duration to protect against any increase in the price of securities the fund anticipates purchasing at a later date; or gain exposure to certain markets in the most economical way possible.
Swap agreements are two-party contracts entered into primarily by institutional investors for periods ranging from a few weeks to more than one year. In a standard “swap” transaction, two parties agree to exchange the returns (or differentials in rates of return) earned or realized on particular predetermined investments or instruments, which may be adjusted for an interest factor. The gross returns to be exchanged or “swapped” between the parties are generally calculated with respect to a “notional amount,” i.e., the return on or increase in value of a particular dollar amount invested at a particular interest rate, in a particular foreign currency, or in a “basket” of securities representing a particular index. Forms of swap agreements include, for example, interest rate swaps, under which fixed- or floating-rate interest payments on a specific principal amount are exchanged and total return swaps, under which one party agrees to pay the other the total return of a defined underlying asset (usually an index, including inflation indexes, stock, bond or defined portfolio of loans and mortgages) in exchange for fee payments, often a variable stream of cash flows based on LIBOR. The funds may enter into credit default swap agreements to hedge an existing position by purchasing or selling credit protection. Credit default swaps enable an investor to buy/sell protection against a credit event of a specific issuer. The seller of credit protection against a security or basket of securities receives an up-front or periodic payment to compensate against potential default event(s). The funds may enhance returns by selling protection or attempt to mitigate credit risk by buying protection. Market supply and demand factors may cause distortions between the cash securities market and the credit default swap market.
Whether a fund’s use of swap agreements will be successful depends on the advisor’s ability to predict correctly whether certain types of investments are likely to produce greater returns than other investments. Interest rate swaps could result in losses if interest rate changes are not correctly anticipated by the fund. Total return swaps could result in losses if the reference index, security, or investments do not perform as anticipated by the fund. Credit default swaps could result in losses if the fund does not correctly evaluate the creditworthiness of the issuer on which the credit default swap is based. Because they are two-party contracts and because they may have terms of greater than seven days, swap agreements may be considered to be illiquid. Moreover, a fund 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 swap agreement counterparty. The funds will enter into swap agreements only with counterparties that meet certain standards of creditworthiness or that are cleared through a Derivatives Clearing Organization (“DCO”). Certain restrictions imposed on the funds by the Internal Revenue Code may limit the funds’ ability to use swap agreements.

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The swaps market is an evolving market and was largely unregulated prior to the enactment of the Dodd-Frank Wall Street Reform and Consumer Protection Act (the “Dodd-Frank Act”). The Dodd-Frank Act and related regulatory developments have imposed several new requirements on swap market participants, including: (i) new registration and business conduct requirements on swap dealers; (ii) mandatory execution of certain swaps on swap execution facilities or designated contract markets; and (iii) mandatory clearing of certain swaps with DCOs. The mandatory execution and clearing requirements will occur on a phased-in basis. Although central clearing is designed to decrease counterparty risk, it does not do so entirely since a fund will still be subject to the credit risk of the central clearing entity. In addition, swaps that are not cleared will be subject to regulatory collateral requirements that could limit or adversely affect a fund’s ability to enter into such swaps. Additionally, such collateral requirements, or other government regulations, could cause a fund to terminate new or existing swaps or to realize amounts to be received under such instruments at inopportune times.
Tender Option Bonds
The American Century Diversified Corporate Bond ETF may invest in Tender Option Bonds. Tender Option Bonds (TOBs) were created to increase the supply of high-quality, short-term tax-exempt obligations, and thus they are of particular interest to money market funds.
TOBs are created by municipal bond dealers who purchase long-term tax-exempt bonds in the secondary market, place the certificates in trusts, and sell interests in the trusts with puts or other liquidity guarantees attached. The credit quality of the resulting synthetic short-term instrument is based on the put provider’s short-term rating and the underlying bond’s long-term rating.
There is some risk that a remarketing agent will renege on a tender option agreement if the underlying bond is downgraded or defaults. Because of this, the portfolio managers monitor the credit quality of bonds underlying the fund’s TOB holdings and intend to sell or put back any TOB if the rating on the underlying bond falls below the second-highest rating category designated by a rating agency.
Tracking and Correlation
The American Century STOXX® U.S. Quality Value ETF seeks to provide investment results that closely correspond, before fees and expenses, to the performance of its underlying index, although several factors may affect their ability to achieve this correlation, including, but not limited to: (1) the fund’s expenses, including brokerage (which may be increased by high portfolio turnover) and the cost of the investment techniques employed by the fund; (2) the fund’s holding of less than all of the securities in the underlying index, including as part of a “representative sampling” strategy, and holding securities not included in the underlying index; (3) an imperfect correlation between the performance of the fund’s investments and those of its underlying index; (4) bid-ask spreads (the effect of which may be increased by portfolio turnover); (5) holding instruments traded in a market that has become illiquid or disrupted; (6) the fund’s share prices being rounded to the nearest cent; (7) changes to the underlying index that are not disseminated in advance; (8) the need to conform the fund’s portfolio holdings to comply with investment restrictions or policies, or regulatory or tax law requirements; (9) early and unanticipated closings of the markets on which the holdings of the fund trade, resulting in the inability of the fund to execute intended portfolio transactions; and (10) the fund’s holdings of cash or cash equivalents, or otherwise not being fully invested in securities of its underlying index. While close tracking of the fund to its underlying index may be achieved on any single trading day, over time the cumulative percentage increase or decrease in the NAV of the shares of the fund may diverge significantly from the cumulative percentage decrease or increase in the underlying index due to a compounding effect.
U.S. Government Securities
The funds may invest in U.S. government securities, including bills, notes and bonds issued by the U.S. Treasury and securities issued or guaranteed by agencies or instrumentalities of the U.S. government. Some U.S. government securities are supported by the direct full faith and credit pledge of the U.S. government; others are supported by the right of the issuer to borrow from the U.S. Treasury; others, such as securities issued by the Federal National Mortgage Association (FNMA), are supported by the discretionary authority of the U.S. government to purchase the agencies’ obligations; and others are supported only by the credit of the issuing or guaranteeing instrumentality. There is no assurance that the U.S. government will provide financial support to an instrumentality it sponsors when it is not obligated by law to do so.
Variable-, Floating- and Auction-Rate Securities
The American Century Diversified Corporate Bond ETF may invest in variable-, floating- and auction-rate securities. Variable- and floating-rate securities, including floating-rate notes (FRNs), provide for periodic adjustments to the interest rate. The adjustments are generally based on an index-linked formula, or determined through a remarketing process.
These types of securities may be combined with a put or demand feature that permits the fund to demand payment of principal plus accrued interest from the issuer or a financial institution. One example is the variable-rate demand note (VRDN). VRDNs combine a demand feature with an interest rate reset mechanism designed to result in a market value for the security that approximates par. VRDNs are generally designed to meet the requirements of money market fund Rule 2a-7.

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Auction Rate Securities (ARS) are variable rate bonds whose interest rates are reset at specified intervals through a Dutch auction process. A Dutch auction is a competitive bidding process designed to determine a single uniform clearing rate that enables purchases and sales of the ARS to take place at par. All accepted bids and holders of the ARS receive the same rate. ARS holders rely on the liquidity generated by the Dutch auction. There is a risk that an auction will fail due to insufficient demand for the securities. If an auction fails, an ARS may become illiquid until either a subsequent successful auction is conducted, the issuer redeems the issue, or a secondary market develops.
When-Issued and Forward Commitment Agreements
The funds may sometimes purchase new issues of securities on a when-issued or forward commitment basis in which the transaction price and yield are each fixed at the time the commitment is made, but payment and delivery occur at a future date.
For example, a fund may sell a security and at the same time make a commitment to purchase the same or a comparable security at a future date and specified price. Conversely, a fund may purchase a security and at the same time make a commitment to sell the same or a comparable security at a future date and specified price. These types of transactions are executed simultaneously in what are known as dollar-rolls, buy/sell back transactions, cash and carry, or financing transactions. For example, a broker-dealer may seek to purchase a particular security that a fund owns. The fund will sell that security to the broker-dealer and simultaneously enter into a forward commitment agreement to buy it back at a future date. This type of transaction generates income for the fund if the dealer is willing to execute the transaction at a favorable price in order to acquire a specific security.
When purchasing securities on a when-issued or forward commitment basis, a fund assumes the rights and risks of ownership, including the risks of price and yield fluctuations. Market rates of interest on debt securities at the time of delivery may be higher or lower than those contracted for on the when-issued security. Accordingly, the value of the security may decline prior to delivery, which could result in a loss to the fund. While the fund will make commitments to purchase or sell securities with the intention of actually receiving or delivering them, it may sell the securities before the settlement date if doing so is deemed advisable as a matter of investment strategy.
In purchasing securities on a when-issued or forward commitment basis, a fund will segregate cash, cash equivalents or other appropriate liquid securities on its records in an amount sufficient to meet the purchase price. To the extent a fund remains fully invested or almost fully invested at the same time it has purchased securities on a when-issued basis, there will be greater fluctuations in its net asset value than if it solely set aside cash to pay for when-issued securities. When the time comes to pay for the when-issued securities, a fund will meet its obligations with available cash, through the sale of securities, or, although it would not normally expect to do so, by selling the when-issued securities themselves (which may have a market value greater or less than the fund’s payment obligation). Selling securities to meet when-issued or forward commitment obligations may generate taxable capital gains or losses.
Zero-Coupon, Step-Coupon, Range Floaters and Pay-In-Kind Securities
The American Century Diversified Corporate Bond ETF may purchase zero-coupon debt securities. Zero-coupon debt securities do not make regular cash interest payments, and are sold at a deep discount to their face value.
The fund may also purchase step-coupon or step-rate debt securities. Instead of having a fixed coupon for the life of the security, coupon or interest payments may increase to predetermined rates at future dates. The issuer generally retains the right to call the security. Some step-coupon securities are issued with no coupon payments at all during an initial period, and only become interest-bearing at a future date; these securities are sold at a deep discount to their face value.
Finally, the fund may purchase pay-in-kind securities that do not make regular cash interest payments, but pay interest through the issuance of additional securities. Because such securities do not pay current cash income, the price of these securities can be volatile when interest rates fluctuate.
Although zero-coupon, pay-in-kind and certain range floaters and step-coupon securities may not pay current cash income, federal income tax law requires the holder to include in income each year the portion of any original issue discount and other noncash income on such securities accrued during that year. In order to continue to qualify for treatment as a regulated investment company under the Internal Revenue Code and avoid certain excise tax, the fund is required to make distributions of any original issue discount and other noncash income accrued for each year. Accordingly, the fund may be required to dispose of other portfolio securities, which may occur in periods of adverse market prices, in order to generate a case to meet these distribution requirements.
Investment Policies
Unless otherwise indicated, with the exception of the percentage limitations on borrowing, the following policies apply at the time a fund enters into a transaction. Accordingly, any later increase or decrease beyond the specified limitation resulting from a change in a fund’s assets will not be considered in determining whether it has complied with its investment policies.
Fundamental Investment Policies
The funds’ fundamental investment policies are set forth below. These investment policies and a fund’s status as diversified may not be changed without approval of a majority of the outstanding votes of shareholders of a fund. Under the Investment Company Act, the vote of a majority of the outstanding votes of shareholders means, the vote of (A) 67 percent or more of the voting

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securities present at a shareholder meeting, if the holders of more than 50 percent of the outstanding voting securities are present or represented by proxy; or (B) more than 50 percent of the outstanding voting securities, whichever is less.
Subject
Policy
Senior
Securities
A fund may not issue senior securities, except as permitted under the Investment Company Act.
Borrowing
A fund may not borrow money, except to the extent permitted by the Investment Company Act, or any rules, exemptions or interpretations thereunder that may be adopted, granted or issued by the SEC.
Lending
A fund may not make loans if, as a result, more than 33 1/3% of its total assets would be lent to other persons, including other investment companies to the extent permitted by the Investment Company Act or any rules, exemptions or interpretations thereunder that may be adopted, granted or issued by the SEC. This limitation does not apply to (i) the lending of portfolio securities, (ii) the purchase of debt securities, other debt instruments, loan participations and/or engaging in direct corporate loans in accordance with its investment goals and policies, and (iii) repurchase agreements to the extent the entry into a repurchase agreement is deemed to be a loan.
Real Estate
A fund may not purchase or sell real estate unless acquired as a result of ownership of securities or other instruments. This policy shall not prevent a fund from investing in securities or other instruments backed by real estate or securities of companies that deal in real estate or are engaged in the real estate business.
Concentration
A fund may not concentrate its investments in securities of issuers in a particular industry (other than securities issued or guaranteed by the U.S. government or any of its agencies or instrumentalities), except that the American Century STOXX® U.S. Quality Value ETF will concentrate to approximately the same extent that its underlying index concentrates in the securities of a particular industry or group of industries. Accordingly, if the American Century STOXX® U.S. Quality Value ETF’s underlying index stops concentrating in the securities of a particular industry or group of industries, the fund will also discontinue concentrating in such securities.
Underwriting
A fund may not act as an underwriter of securities issued by others, except to the extent that the fund may be considered an underwriter within the meaning of the 1933 Act in the disposition of restricted securities.
Commodities
A fund may not purchase or sell commodities, except to the extent permitted by the 1940 Act or any rules, exemptions or interpretations thereunder that may be adopted, granted or issued by the SEC.
For purposes of the investment policy relating to senior securities, a fund may borrow from any bank provided that immediately after any such borrowing there is asset coverage of at least 300% for all borrowings of such fund. In the event that such asset coverage falls below 300%, the fund shall, within three days thereafter (not including Sundays and holidays) or such longer period as the SEC may prescribe by rules and regulations, reduce the amount of its borrowings to an extent that the asset coverage of such borrowings is at least 300%. In addition, when a fund enters into certain transactions involving potential leveraging, it will hold offsetting positions or segregate assets to cover such obligations at levels consistent with the guidance of the SEC and its staff.
In complying with the fundamental investment policy relating to concentration:
(a)
there is no limitation with respect to obligations issued or guaranteed by the U.S. government, any state, territory or possession of the United States, the District of Columbia or any of their authorities, agencies, instrumentalities or political subdivisions and repurchase agreements secured by such obligations (except that an Industrial Development Bond backed only by the assets and revenues of a non-governmental user will be deemed to be an investment in the industry represented by such user);
(b)
wholly owned finance companies will be considered to be in the industries of their parents if their activities are primarily related to financing the activities of their parents;
(c)
utilities will be divided according to their services, for example, gas, gas transmission, electric and gas, electric and telephone will each be considered a separate industry; and
(d)
personal credit and business credit businesses will be considered separate industries.
Although the funds’ fundamental investment policy relating to commodities would permit investments in commodities, neither fund currently intends to purchase or sell physical commodities unless acquired as a result of ownership of securities or other instruments. The funds may, however, purchase or sell options and futures contracts or invest in securities or other instruments backed by physical commodities to the extent permitted by such fund’s investment objectives and policies.
Nonfundamental Investment Policies
The funds are subject to the following investment policies that are not fundamental and may be changed by the Board of Trustees.
Each fund’s investment objective is a nonfundamental investment policy and may be changed by the Board of Trustees without approval by shareholders upon 60 days’ prior notice to shareholders.
Each fund has adopted a nonfundamental investment policy in accordance with Rule 35d-1 under the 1940 Act to invest at least 80% of its assets in the type of investments suggested by the fund’s name. For purposes of such investment policy, “assets” include the fund’s net assets, plus the amount of any borrowings for investment purposes. The American Century STOXX® U.S. Quality

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Value ETF considers the securities or investments that are the type of investments suggested by the fund’s name to be those securities or investments that comprise the underlying index. The Diversified Corporate Bond will invest at least 80% of the fund’s assets in corporate debt securities and investments. Each fund’s 80% policy is nonfundamental, which means that it may be changed by the board of trustees without the approval of shareholders. Shareholders will be given at least 60 days’ advance notice of any change to a fund’s 80% policy.
A fund may not purchase any security or enter into a repurchase agreement if, as a result, more than 15% of its net assets would be invested in illiquid securities. Illiquid securities include repurchase agreements not entitling the holder to payment of principal and interest within seven days, and securities that are illiquid by virtue of legal or contractual restrictions on resale or the absence of a readily available market.
The Investment Company Act imposes certain additional restrictions upon the funds’ ability to acquire securities issued by insurance companies, broker-dealers, underwriters or investment advisors, and upon transactions with affiliated persons as defined by the Act. It also defines and forbids the creation of cross and circular ownership. Neither the SEC nor any other agency of the federal or state government participates in or supervises the management of the funds or their investment practices or policies.
Temporary Defensive Measures
For temporary defensive purposes, the American Century Diversified Corporate Bond ETF may invest in securities that may not fit its investment objective or its stated market. During a temporary defensive period, the fund may direct its assets without limit to the following investment vehicles:
interest-bearing bank accounts or certificates of deposit;
U.S. government securities and repurchase agreements collateralized by U.S. government securities; and
other money market funds.
To the extent a fund assumes a defensive position, it may not achieve its investment objective.
Portfolio Turnover
The portfolio turnover rate of each fund for its most recent fiscal year will be included in the Fund Summary section of that fund’s prospectus. The portfolio turnover rate for each fund’s last five fiscal years (or a shorter period if the fund is less than five years old) will be shown in the Financial Highlights tables in the prospectus. Variations in a fund’s portfolio turnover rate from year to year may be due to a fluctuating volume of shareholder purchase and redemption activity, varying market conditions, and/or changes in the managers’ investment outlook.
The portfolio managers will sell securities without regard to the length of time the security has been held. Because the portfolio managers do not take portfolio turnover rate into account in making investment decisions, (1) the managers have no intention of maintaining any particular rate of portfolio turnover, whether high or low; and (2) the portfolio turnover rates in the past should not be considered as representative of the rates that will be attained in the future.
Disclosure of Portfolio Holdings
ACIM has adopted policies and procedures with respect to the disclosure of fund portfolio holdings and characteristics, which are described below.
Distribution to the Public
On each business day of a fund, before commencement of trading in shares on a national securities exchange, the fund will disclose on its website the identities and quantities of the fund’s portfolio holdings that will form the basis for the fund’s calculation of NAV at the end of that business day.
Portfolio holdings are also disclosed in annual and semiannual shareholder reports, and on Form N-Q, which disclosures are filed with the SEC within 60 days of each fiscal quarter end and also posted on americancenturyetfs.com at the time the filings are made.
In addition, each business day, each fund’s portfolio holdings information will be provided to the funds’ transfer agent or other agents for dissemination through the facilities of the National Securities Clearing Corporation (NSCC) and/or other fee-based subscription services to NSCC members and/or subscribers to those other fee-based subscription services, including large institutional investors (known as “Authorized Participants”) that have been authorized to purchase and redeem large blocks of shares pursuant to legal requirements, and to entities that publish and/or analyze such information in connection with the process of purchasing or redeeming Creation Units or trading shares of a fund in the secondary market.
Portfolio holdings information made available in connection with the creation/redemption process may be provided to other entities that provide services to the fund in the ordinary course of business after it has been disseminated to the NSCC. From time to time, information concerning portfolio holdings other than portfolio holdings information made available in connection with the creation/redemption process, as discussed above, may be provided to other entities that provide services to a fund in the ordinary course of business, no earlier than one business day following the date of the information. The eligible third parties to whom

26



portfolio holdings information may be released in advance of general release fall into the following categories: data consolidators (including rating agencies), fund rating/ranking services and other data providers and service providers to the fund, including Authorized Participants and pricing services.
Continuous Offering
The method by which Creation Units are created and traded may raise certain issues under applicable securities laws. Because new Creation Units are issued and sold by the funds on an ongoing basis, at any point a “distribution,” as such term is used in the 1933 Act, may occur. Broker-dealers and other persons are cautioned that some activities on their part may, depending on the circumstances, result in their being deemed participants in a distribution in a manner that could render them statutory underwriters and subject them to the prospectus delivery requirement and liability provisions of the 1933 Act.
For example, a broker-dealer firm or its client may be deemed a statutory underwriter if it takes Creation Units after placing an order with the transfer agent, breaks them down into constituent shares and sells such shares directly to customers or if it chooses to couple the creation of new shares with an active selling effort involving solicitation of secondary market demand for shares. A determination of whether one is an underwriter for purposes of the 1933 Act must take into account all the facts and circumstances pertaining to the activities of the broker-dealer or its client in the particular case and the examples mentioned above should not be considered a complete description of all the activities that could lead to a categorization as an underwriter.
Broker-dealer firms should also note that dealers who are not “underwriters” but are effecting transactions in shares, whether or not participating in the distribution of shares, generally are required to deliver a prospectus. This is because the prospectus delivery exemption in Section 4(a)(3) of the 1933 Act is not available in respect of such transactions as a result of Section 24(d) of the 1940 Act. Firms that incur a prospectus delivery obligation with respect to shares of the fund are reminded that, pursuant to Rule 153 under the 1933 Act, a prospectus delivery obligation under Section 5(b)(2) of the 1933 Act owed to an exchange member in connection with a sale on the Listing Exchange is satisfied by the fact that the prospectus is available at the Listing Exchange upon request. The prospectus delivery mechanism provided in Rule 153 is available only with respect to transactions on an exchange.
Management
The Board of Trustees
The individuals listed below serve as trustees of the funds. Each trustee will continue to serve in this capacity until death, retirement, resignation or removal from office. The board has adopted a mandatory retirement age for trustees who are not “interested persons,” as that term is defined in the Investment Company Act (independent trustees). Trustees who are not also officers of the trust shall retire by December 31st of the year in which they reach their 75th birthday.
Jonathan Thomas is an “interested person” because he currently serves as President and Chief Executive Officer of American Century Companies, Inc. (ACC), the parent company of American Century Investment Management, Inc. (ACIM or the advisor). Reginald Browne is also an “interested person” because he currently serves as Senior Managing Director-ETF Group at Cantor Fitzgerald. Cantor Fitzgerald executes portfolio transactions for, and engages in principal transactions with, certain funds in the American Century family that also have ACIM as their advisor. The other trustees are independent. They are not employees, directors or officers of, and have no financial interest in, ACC or any of its wholly owned, direct or indirect, subsidiaries, including ACIM and American Century Services, LLC (ACS), and they do not have any other affiliations, positions or relationships that would cause them to be considered “interested persons” under the Investment Company Act. The following trustees also serve in this capacity for a number of other registered investment companies in the American Century Investments family of funds: Jonathan Thomas, 15; Ronald Gilson, 7; and Stephen Yates, 8.
The following table presents additional information about the trustees. The mailing address for each trustee other than Jonathan Thomas is 330 Madison Avenue, New York, New York 10017. The mailing address for Jonathan Thomas is 4500 Main Street, Kansas City, Missouri 64111.

27



Name (Year of Birth)
Position(s)
Held with
Funds
Length of
Time Served
Principal Occupation(s) During Past 5 Years
Number of
American
Century
Portfolios
Overseen
by Trustee
Other Directorships
Held During Past
5 Years
Independent Trustees
 
 
 
 
Ronald J. Gilson
(1946)
Trustee
Since 2017
Charles J. Meyers Professor of Law and Business, Emeritus, Stanford Law School (1979 to 2016); Marc and Eva Stern Professor of Law and Business, Columbia University School of Law (1992 to present)
47
None
Barry A. Mendelson
(1958)
Trustee
Since 2017
Retired; Consultant regarding ETF and mutual fund matters (2015 to 2016); Principal and Senior Counsel, The Vanguard Group (investment management)(1998 to 2014)
2
None
Stephen E. Yates
(1948)
Trustee
Since 2017
Retired
71
None
Interested Trustees
 
 
 
 
Reginald M. Browne
(1968)

Trustee
Since 2017
Senior Managing Director, Co Global Head-ETF Group, Cantor Fitzgerald (financial services firm)(2013 to present); Managing Director, Co Global Head-ETF Group, Knight Capital Group (financial services firm)(2009 to 2013)
2
None
Jonathan S. Thomas
(1963)
Trustee and President
Since 2017
President and Chief Executive Officer, ACC (March 2007 to present). Also serves as Chief Executive Officer, ACS; Executive Vice President, ACIM; Director, ACC, ACIM and other ACC subsidiaries
116
BioMed Valley Discoveries, Inc.
Qualifications of Trustees
Generally, no one factor was decisive in the selection of the trustees to the board. Qualifications considered by the board to be important to the selection and retention of trustees include the following: (i) the individual’s business and professional experience and accomplishments; (ii) the individual’s educational background and accomplishments; (iii) the individual’s experience and expertise performing senior policy-making functions in business, government, education, accounting, law and/or administration; (iv) how the individual’s expertise and experience would contribute to the mix of relevant skills and experience on the board; (v) the individual’s ability to work effectively with the other members of the board; and (vi) the individual’s ability and willingness to make the time commitment necessary to serve as an effective trustee. In addition, the individuals’ ability to review and critically evaluate information, their ability to evaluate fund service providers, their ability to exercise good business judgment on behalf of fund shareholders, their prior service on the board, and their familiarity with the funds are considered important assets.
While the board has not adopted a specific policy on diversity, it takes overall diversity into account when considering and evaluating nominees for trustee. The board generally considers the manner in which each trustee’s professional experience, background, skills, and other individual attributes will contribute to the effectiveness of the board. Additional information about each trustee’s individual educational and professional experience (supplementing the information provided in the table above) follows and was considered as part of his or her nomination to, or retention on, the board.
Reginald M. Browne: BS in Business Administration, La Salle University; 15 years’ experience in the ETF industry with a core focus on market-making and institutional sales
Ronald J. Gilson: BA, Washington University; JD, Yale Law School; formerly, Attorney, Steinhart, Goldberg, Feigenbaum & Ladar

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Barry A. Mendelson: AB, Geology, Vassar College; JD, The George Washington University School of Law; eight years’ experience with the U.S. Securities and Exchange Commission, Division of Investment Management
Jonathan S. Thomas: BA in Economics, University of Massachusetts; MBA, Boston College; formerly held senior leadership roles with Fidelity Investments, Boston Financial Services, Bank of America and Morgan Stanley; serves on the Board of Governors of the Investment Company Institute 
Stephen E. Yates: BS and MS in Industrial Engineering, University of Alabama; formerly, Executive Vice President, Technology & Operations, KeyCorp. (computer services); formerly, President, USAA Information Technology Company (financial services); 33 years’ of experience in Information Technology; formerly, Director, Applied Industrial Technologies, Inc.
Responsibilities of the Board
The board is responsible for overseeing the advisor’s management and operations of the funds pursuant to the management agreement. Trustees also have significant responsibilities under the federal securities laws. Among other things, they:
oversee the performance of the funds;
oversee the quality of the advisory and shareholder services provided by the advisor;
review annually the fees paid to the advisor for its services;
monitor potential conflicts of interest between the funds and their affiliates, including the advisor;
oversee custody of assets and the valuation of securities; and
oversee the funds’ compliance program.
In performing their duties, board members receive detailed information about the funds and the advisor regularly throughout the year, and they meet in person at least quarterly with management of the advisor to review reports about fund operations. The trustees’ role is to provide oversight and not to provide day-to-day management.
The board has all powers necessary or convenient to carry out its responsibilities. Consequently, the board may adopt bylaws providing for the regulation and management of the affairs of the funds and may amend and repeal them to the extent that such bylaws do not reserve that right to the funds’ shareholders. They may increase or reduce the number of board members and may, subject to the Investment Company Act, fill board vacancies. Board members also may elect and remove such officers and appoint and terminate such agents as they consider appropriate. They may establish and terminate committees consisting of two or more trustees who may exercise the powers and authority of the board as determined by the trustees. They may, in general, delegate such authority as they consider desirable to any officer of the funds, to any board committee and to any agent or employee of the funds or to any custodian, transfer agent, investor servicing agent, principal underwriter or other service provider for a fund.
To communicate with the board, or a member of the board, a shareholder should send a written communication addressed to the board or member of the board to the attention of the Corporate Secretary at the following address: P.O. Box 418210, Kansas City, Missouri 64141-9210. Shareholders who prefer to communicate by email may send their comments to corporatesecretary@americancentury.com. All shareholder communications received will be forwarded to the board or the independent chairman of the board.
Board Leadership Structure and Standing Board Committees
Jonathan S. Thomas, an interested trustee, currently serves as the chairman of the board and has served in such capacity since the board was formally constituted in November 2017. The independent trustees have not designated a lead independent trustee. The relatively small size of the board facilitates communication among the trustees, and between the trustees and management, and the board has concluded that designating one of the three independent trustees as the “lead” would not meaningfully enhance the effectiveness of the board. The independent trustees meet separately to consider a variety of matters that are scheduled to come before the board and meet periodically with the funds’ Chief Compliance Officer and fund auditors. They are advised by independent legal counsel. No independent trustee may serve as an officer or employee of a fund. The board has also established an Audit Committee, described below, comprised solely of independent trustees. The board believes that the current leadership structure is appropriate and allows for independent oversight of the funds.
The board has an Audit Committee that approves the funds’ (or trust’s) engagement of the independent registered public accounting firm and recommends approval of such engagement to the independent trustees. The committee also oversees the activities of the accounting firm, receives regular reports regarding fund accounting, oversees securities valuation (approving the funds’ valuation policy and receiving reports regarding instances of fair valuation thereunder) and receives regular reports from the advisor’s internal audit department. The committee currently consists of Barry A. Mendelson (chair), Ronald J. Gilson and Stephen E. Yates.
Risk Oversight by the Board
As previously disclosed, the board oversees the advisor’s management of the funds and meets at least quarterly with management of the advisor to review reports and receive information regarding fund operations. Risk oversight relating to the funds is one component of the board’s oversight and is undertaken in connection with the duties of the board. The board oversees various types

29



of risks relating to the funds, including, but not limited to, investment risk, operational risk and enterprise risk. Through its regular interactions with management of the advisor during and between meetings, the board will analyze, evaluate, and provide feedback on the advisor’s risk management processes. In addition, the board will receive information regarding, and have discussions with senior management of the advisor about, the advisor’s enterprise risk management systems and strategies. There can be no assurance that all elements of risk, or even all elements of material risk, will be disclosed to or identified by the board, or that the advisor’s risk management systems and strategies, and the board’s oversight thereof, will mitigate all elements of risk, or even all elements of material risk to the funds.
Board Compensation
The funds and the American Century family of funds paid the trustees listed in the following table the amounts shown for the fiscal year ended August 31, 2017. Neither Jonathan Thomas nor any officers of the funds receives compensation from the funds.
Name of Trustee
Total Compensation
from the Trust(1)
Total Compensation from the American
Century Investments Family of Funds(1)
Reginald M. Browne
n/a
n/a
Ronald J. Gilson
n/a
$350,000
Barry A. Mendelson
n/a
n/a
Stephen E. Yates
n/a
$314,000
1 As of August 31, 2017, the trust had not yet commenced operations. Estimated total compensation from the trust for the fiscal year ended August 31, 2018 is as follows: Mr. Browne, $29,167; Mr. Gilson, $29,167; Mr. Mendelson, $33,333, Mr. Yates, $29,167
2 Includes deferred compensation paid under the American Century Mutual Funds’ Independent Directors’ Deferred Compensation Plan as follows: Mr. Gilson, $350,000; Mr. Yates, $314,000.
The funds do not currently provide any pension or retirement benefits to the trustees.
Ownership of Fund Shares
The trust and each fund is newly established. As of the date of this SAI, none of the trustees held equity securities in the trust or funds.
Beneficial Ownership of Affiliates by Independent Trustees
No independent trustee or his or her immediate family members beneficially owned shares of the advisor, the funds’ principal underwriter or any other person directly or indirectly controlling, controlled by, or under common control with the advisor or the funds’ principal underwriter as of the date of this SAI.
Officers
The following table presents certain information about the executive officers of the funds. Each officer, except Edward Rosenberg and Peruvemba Satish, serves as an officer for each of the 16 investment companies in the American Century family of funds. No officer is compensated for his or her service as an officer of the funds. The listed officers are interested persons of the funds and are appointed or re-appointed on an annual basis. The mailing address for each officer listed below is 4500 Main Street, Kansas City, Missouri 64111.

30



Name
(Year of Birth)
Offices with the Funds
Principal Occupation(s) During the Past Five Years
Jonathan S.
Thomas
(1963)
Trustee and
President
since 2017
President and Chief Executive Officer, ACC (2007 to present). Also serves as Chief Executive Officer, ACS; Executive Vice President, ACIM; Director, ACC, ACIM and other ACC subsidiaries
C. Jean Wade
(1964)
Vice President,
Treasurer and
Chief Financial
Officer since 2017
Vice President, ACS (2000 to present)
Amy D. Shelton
(1964)
Chief Compliance
Officer and Vice President since 2017
Chief Compliance Officer, American Century funds, (2014 to present); Chief Compliance Officer, ACIM (2014 to present); Chief Compliance Officer, ACIS (2009 to present); Vice President, Client Interactions and Marketing, ACIS (2013 to 2014); Director, Client Interactions and Marketing, ACIS (2007 to 2013). Also serves as Vice President, ACIS
Charles A.
Etherington
(1957)
General Counsel and
Vice President since 2017
Attorney, ACC (1994 to present); Vice President, ACC (2005 to present), General Counsel, ACC (2007 to present). Also serves as General Counsel, ACIM, ACS, ACIS and other ACC subsidiaries; and Senior Vice President, ACIM and ACS
David H.
Reinmiller
(1963)
Vice President
since 2017
Attorney, ACC (1994 to present); Associate General Counsel, ACC (2001 to present). Also serves as Vice President, ACIM and ACS
Edward Rosenberg (1973)
Vice President since 2017
Senior Vice President, ACIM (2017 to present); Senior Vice President, Flexshares Head of ETF Capital Markets, Northern Trust (2012 to 2017)
Peruvemba Satish
(1965)
Vice President since 2017
Senior Vice President, Portfolio Manager and Director, Global Analytics, ACIM (2014 to present); Senior Managing Director, Allstate Investment Management Company (2013 to 2014); Managing Director, Allstate Investment Management Company (2010 to 2012)
Ward D.
Stauffer
(1960)
Secretary
since 2017
Attorney, ACC (2003 to present)

Code of Ethics
The funds and the advisor have adopted codes of ethics under Rule 17j-1 of the Investment Company Act. They permit personnel subject to the codes to invest in securities, including securities that may be purchased or held by the funds, provided that they first obtain approval from the compliance department before making such investments. The funds’ distributor (Foreside Fund Services, LLC) relies on the principal underwriters exception under Rule 17j-1(c)(3), specifically where the distributor is not affiliated with the Trust or the advisor, and no officer, director or general partner of the distributor serves as an officer, director or general partner of the Trust or the advisor.
Proxy Voting Policies
The advisor is responsible for exercising the voting rights associated with the securities purchased and/or held by the funds. The funds’ Board of Trustees has approved the advisor’s proxy voting policies to govern the advisor’s proxy voting activities.
A copy of the advisor’s proxy voting policies is attached hereto as Appendix B. Information regarding how the advisor voted proxies relating to portfolio securities during the most recent 12-month period ended June 30 will be available on the About Us page at americancentury.com. The advisor’s proxy voting record also is available on the SEC’s website at sec.gov.
The Funds’ Principal Shareholders
The trust does not have information concerning the beneficial ownership of shares held by DTC Participants (as defined below).
Following the creation of the initial Creation Unit(s) of shares of a fund and immediately prior to the commencement of trading in the fund’s shares, a holder of shares may be a “control person” of the fund, as defined in the Investment Company Act. A fund cannot predict the length of time for which one or more shareholders may remain a control person of the fund.
Depository Trust Company (DTC) acts as securities depository for shares of the funds. Shares of the funds are represented by securities registered in the name of DTC or its nominee and deposited with, or on behalf of, DTC.
DTC was created in 1973 to enable electronic movement of securities between its participants (DTC Participants), and NSCC was established in 1976 to provide a single settlement system for securities clearing and to serve as central counterparty for securities trades among DTC Participants. In 1999, DTC and NSCC were consolidated within the Depository Trust & Clearing Corporation (DTCC) and became wholly owned subsidiaries of DTCC. The common stock of DTCC is owned by the DTC Participants, but the New York Stock Exchange and FINRA, through subsidiaries, hold preferred shares in DTCC that provide them with the right to

31



elect one member each to the DTCC Board of Directors. Access to the DTC system is available to entities, such as banks, brokers, dealers and trust companies, that clear through or maintain a custodial relationship with a DTC Participant, either directly or indirectly (Indirect Participants).
Beneficial ownership of shares is limited to DTC Participants, Indirect Participants and persons holding interests through DTC Participants and Indirect Participants. Ownership of beneficial interests in shares (owners of such beneficial interests are referred to herein as “Beneficial Owners”) is shown on, and the transfer of ownership is effected only through, records maintained by DTC (with respect to DTC Participants) and on the records of DTC Participants (with respect to Indirect Participants and Beneficial Owners that are not DTC Participants). Beneficial Owners will receive from or through the DTC Participant a written confirmation relating to their purchase of shares. The laws of some jurisdictions may require that certain purchasers of securities take physical delivery of such securities in definitive form. Such laws may impair the ability of certain investors to acquire beneficial interests in shares.
Conveyance of all notices, statements and other communications to Beneficial Owners is effected as follows. Pursuant to the Depositary Agreement between the trust and DTC, DTC is required to make available to the trust upon request and for a fee to be charged to the trust a listing of the shares of a fund held by each DTC Participant. The trust shall inquire of each such DTC Participant as to the number of Beneficial Owners holding shares, directly or indirectly, through such DTC Participant. The trust shall provide each such DTC Participant with copies of such notice, statement or other communication, in such form, number and at such place as such DTC Participant may reasonably request, in order that such notice, statement or communication may be transmitted by such DTC Participant, directly or indirectly, to such Beneficial Owners. In addition, the trust shall pay to each such DTC Participant a fair and reasonable amount as reimbursement for the expenses attendant to such transmittal, all subject to applicable statutory and regulatory requirements.
Share distributions shall be made to DTC or its nominee, Cede & Co., as the registered holder of all shares of the trust. DTC or its nominee, upon receipt of any such distributions, shall credit immediately DTC Participants’ accounts with payments in amounts proportionate to their respective beneficial interests in shares of the fund as shown on the records of DTC or its nominee. Payments by DTC Participants to Indirect Participants and Beneficial Owners of shares held through such DTC Participants will be governed by standing instructions and customary practices, as is now the case with securities held for the accounts of customers in bearer form or registered in a “street name,” and will be the responsibility of such DTC Participants.
The trust has no responsibility or liability for any aspect of the records relating to or notices to Beneficial Owners, or payments made on account of beneficial ownership interests in such shares, or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests, or for any other aspect of the relationship between DTC and the DTC Participants or the relationship between such DTC Participants and the Indirect Participants and Beneficial Owners owning through such DTC Participants. DTC may decide to discontinue providing its service with respect to shares of the trust at any time by giving reasonable notice to the trust and discharging its responsibilities with respect thereto under applicable law. Under such circumstances, the trust shall take action to find a replacement for DTC to perform its functions at a comparable cost.
Seed Capital
The advisor or its affiliates (the “Selling Shareholders”) may purchase shares of a fund through a broker-dealer to “seed” funds as they are launched, or may purchase fund shares from other broker-dealers that have previously provided “seed” for funds when they were launched, or otherwise in secondary market transactions. The fund shares are being registered to permit the resale of these fund shares from time to time after purchase. The funds will not receive any of the proceeds from the resale by the Selling Shareholders of these fund shares.
The Selling Shareholders intend to sell all or a portion of the fund shares owned by them and offered hereby from time to time directly or through one or more broker-dealers. The fund shares may be sold on any national securities exchange on which the fund shares may be listed or quoted at the time of sale, in the over-the-counter market or in transactions other than on these exchanges or systems at fixed prices, at prevailing market prices at the time of the sale, at varying prices determined at the time of sale, or at negotiated prices. These sales may be effected in transactions, which may involve crosses or block transactions.
Creation and Redemption of Creation Units
General    
The trust issues and sells shares of the funds only in Creation Units on a continuous basis through the distributor, without a sales load, at a price based on a fund’s NAV next determined after receipt, on any Business Day (as defined below), of an order received by the transfer agent in proper form. On days when the Listing Exchange closes earlier than normal, a fund may require orders to be placed earlier in the day. The following table sets forth the number of shares of the fund that constitute a Creation Unit for each fund.

32



Fund
Shares Per Creation Unit
American Century STOXX® U.S. Quality Value ETF
25,000
American Century Diversified Corporate Bond ETF
50,000
In its discretion, the advisor reserves the right to increase or decrease the number of a fund’s shares that constitute a Creation Unit. The board reserves the right to declare a split or a consolidation in the number of shares outstanding of a fund, and to make a corresponding change in the number of shares constituting a Creation Unit, in the event that the per share price in the secondary market rises (or declines) to an amount that falls outside the range deemed desirable by the board.
A “Business Day” with respect to the funds is any day on which the Listing Exchange on which a fund is listed for trading is open for business. As of the date of this SAI, the Listing Exchange observes the following holidays: New Year’s Day, Martin Luther King, Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day.
To the extent a fund engages in in-kind transactions, the fund intends to comply with the U.S. federal securities laws in accepting securities for deposit and satisfying redemptions with redemption securities by, among other means, assuring that any securities accepted for deposit and any securities used to satisfy redemption requests will be sold in transactions that would be exempt from registration under the 1933 Act. Further, an Authorized Participant that is not a “qualified institutional buyer,” as such term is defined under Rule 144A of the 1933 Act, will not be able to receive securities that are restricted securities eligible for resale under Rule 144A.
Fund Deposit
The consideration for purchase of Creation Units of a fund (except for the American Century Diversified Corporate Bond ETF, which is generally offered in Creation Units solely for cash) generally consists of the Deposit Securities (i.e., the in-kind deposit of a designated portfolio of securities (including any portion of such securities for which cash may be substituted)) and the Cash Component computed as described below. Together, the Deposit Securities and the Cash Component constitute the “Fund Deposit,” which will be applicable (subject to possible amendment or correction) to creation requests received in proper form. With respect to the American Century STOXX® U.S. Quality Value ETF, the Fund Deposit, when combined with the fund’s portfolio securities, is designed to generate performance that has a collective investment profile similar to that of the underlying index. The Fund Deposit represents the minimum initial and subsequent investment amount for a Creation Unit of a fund. The “Cash Component” is an amount equal to the difference between the NAV of the shares (per Creation Unit) and the “Deposit Amount,” which is an amount equal to the market value of the Deposit Securities, and serves to compensate for any differences between the NAV per Creation Unit and the Deposit Amount. Payment of any stamp duty or other similar fees and expenses payable upon transfer of beneficial ownership of the Deposit Securities are the sole responsibility of the Authorized Participant purchasing the Creation Unit.
The American Century Diversified Corporate Bond ETF’s current policy is to accept cash in substitution for the Deposit Securities it might otherwise accept as in-kind consideration for the purchase of Creation Units. The American Century Diversified Corporate Bond ETF may, at times, elect to receive Deposit Securities (i.e., the in-kind deposit of a designated portfolio of securities) and a Cash Component as consideration for the purchase of Creation Units. If the American Century Diversified Corporate Bond ETF elects to accept Deposit Securities, a purchaser’s delivery of the Deposit Securities together with the Cash Component will constitute the “Fund Deposit,” which will represent the consideration for a Creation Unit of the fund. Please see the Cash purchase method section below and the following discussion summarizing the in-kind method for further information on purchasing Creation Units of the fund.
The advisor makes available through the NSCC on each Business Day prior to the opening of business on the Listing Exchange, the list of names and the required number of shares of each Deposit Security and the amount of the Cash Component (if any) to be included in the current Fund Deposit (based on information as of the end of the previous Business Day for a fund). Such Fund Deposit is applicable, subject to any adjustments as described below, to purchases of Creation Units of shares of a fund until such time as the next-announced Fund Deposit is made available.
The identity and number of shares of the Deposit Securities and the amount of the Cash Component changes pursuant to changes in the composition of a fund’s portfolio and as rebalancing adjustments and corporate action events are reflected from time to time by advisor with a view to the investment goal of the fund. The composition of the Deposit Securities and the amount of the Cash Component may also change in response to adjustments to the weighting or composition of the component securities constituting the underlying index (American Century STOXX® U.S. Quality Value ETF) or the fund’s portfolio (American Century Diversified Corporate Bond ETF).
The funds reserve the right to permit or require the substitution of a “cash in lieu” amount to be added to the Cash Component to replace any Deposit Security that may not be available in sufficient quantity for delivery or that may not be eligible for transfer through the facilities of DTC (DTC Facilities) or the clearing process through the Continuous Net Settlement System of the NSCC (NSCC Clearing Process), a clearing agency that is registered with the SEC (as discussed below), or that the Authorized Participant is not able to trade due to a trading restriction. Each fund also reserves the right to permit or require a “cash in lieu” amount in certain circumstances, including circumstances in which: (i) the delivery of the Deposit Security by the Authorized Participant

33



would be restricted under applicable securities or other local laws; (ii) the delivery of the Deposit Security to the Authorized Participant would result in the disposition of the Deposit Security by the Authorized Participant becoming restricted under applicable securities or other local laws; or (iii) in certain other situations.
Cash Purchase Method
Although the trust does not ordinarily permit partial or full cash purchases of Creation Units of the American Century STOXX® U.S. Quality Value ETF, when partial or full cash purchases of Creation Units are available or specified for the fund (Creation Units of the American Century Diversified Corporate Bond ETF are generally offered solely for cash), they will be effected in essentially the same manner as in-kind purchases thereof. In the case of a partial or full cash purchase, the Authorized Participant must pay the cash equivalent of the Deposit Securities it would otherwise be required to provide through an in-kind purchase, plus the same Cash Component required to be paid by an in-kind purchaser.
Creation Units    
To be eligible to place orders and to create a Creation Unit of the fund, an entity must be: (i) a “Participating Party,” i.e., a broker-dealer or other participant in the NSCC Clearing Process, or (ii) a DTC Participant, and, in either case, must have executed an agreement with the distributor with respect to creations and redemptions of Creation Units (Authorized Participant Agreement). A Participating Party or DTC Participant who has executed an Authorized Participant Agreement is referred to as an “Authorized Participant.” All shares of a fund, however created, will be entered on the records of DTC in the name of Cede & Co. for the account of a DTC Participant.
Role of the Authorized Participant    
Creation Units may be purchased only by or through an Authorized Participant that has entered into an Authorized Participant Agreement with the distributor. Such Authorized Participant will agree, pursuant to the terms of such Authorized Participant Agreement and on behalf of itself or any investor on whose behalf it will act, to certain conditions, including that such Authorized Participant will make available in advance of each purchase of shares an amount of cash sufficient to pay the Cash Component, once the net asset value of a Creation Unit is next determined after receipt of the purchase order in proper form, together with the transaction fees described below. An Authorized Participant, acting on behalf of an investor, may require the investor to enter into an agreement with such Authorized Participant with respect to certain matters, including payment of the Cash Component. Investors who are not Authorized Participants must make appropriate arrangements with an Authorized Participant. Investors should be aware that their particular broker may not be an Authorized Participant or may not have executed an Authorized Participant Agreement and that orders to purchase Creation Units may have to be placed by the investor’s broker through an Authorized Participant. As a result, purchase orders placed through an Authorized Participant may result in additional charges to such investor. The trust does not expect to enter into an Authorized Participant Agreement with more than a small number of Authorized Participants.
Placement of Creation Orders    
An Authorized Participant must submit an irrevocable order to purchase shares of a fund, in proper form, no later than the closing time of the regular trading session of the Listing Exchange (normally 4 p.m., Eastern time), and with respect to the American Century Diversified Corporate Bond ETF no later than two hours prior to the closing time of the regular trading session (normally 2 p.m. Eastern time), on any Business Day in order to receive that day’s NAV. On days when the Listing Exchange closes earlier than normal, a fund may require orders for Creation Units to be placed earlier in the day. Orders for Creation Units must be transmitted by an Authorized Participant by telephone or other transmission method acceptable to the transfer agent pursuant to procedures set forth in the Authorized Participant Agreement, as described below. Economic or market disruptions or changes, or telephone or other communication failure, may impede the ability to reach the transfer agent or an Authorized Participant. Orders to create shares of a fund that are submitted on the Business Day immediately preceding a holiday or a day (other than a weekend) when the equity markets in the relevant non-U.S. market are closed may not be accepted. The funds’ deadlines specified above for the submission of purchase orders is referred to as the funds’ “Cutoff Time.” The trust or its designee, in their discretion, may permit the submission of such orders and requests by or through an Authorized Participant at any time (including on days on which the Listing Exchange is not open for business) via communication through the facilities of the transfer agent’s proprietary website maintained for this purpose.
Investors, other than Authorized Participants, are responsible for making arrangements for a creation request to be made through an Authorized Participant. Those placing orders to purchase Creation Units through an Authorized Participant should allow sufficient time to permit proper submission of the purchase order to the transfer agent or its agent by the Cutoff Time on such Business Day.
Upon receiving an order for a Creation Unit, the transfer agent will notify the advisor and the custodian of such order. The custodian will then provide such information to any appropriate sub-custodian.
The Authorized Participant must make available on or before the prescribed settlement date, by means satisfactory to a fund, immediately available or same day funds estimated by the fund to be sufficient to pay the Cash Component next determined after acceptance of the purchase order, together with the applicable purchase transaction fees. Any excess funds will be returned

34



following settlement of the issue of the Creation Unit. Those placing orders should ascertain the applicable deadline for cash transfers by contacting the operations department of the broker or depositary institution effectuating the transfer of the Cash Component. This deadline is likely to be significantly earlier than the Cutoff Time of the fund. Investors should be aware that an Authorized Participant may require orders for purchases of shares placed with it to be in the particular form required by the individual Authorized Participant.
The Authorized Participant is responsible for all transaction-related fees, expenses and other costs (as described below), as well as any applicable cash amounts, in connection with any purchase order.
Once a purchase order has been accepted, it will be processed based on the NAV next determined after such acceptance in accordance with the fund’s Cutoff Times as provided in the Authorized Participant Agreement and disclosed in this SAI.
Acceptance of Orders for Creation Units    
Subject to the conditions that (i) an irrevocable purchase order has been submitted by the Authorized Participant (either on its own or another investor’s behalf) and (ii) arrangements satisfactory to the fund are in place for payment of the Cash Component and any other cash amounts which may be due, an order will be accepted, subject to the fund’s right to reject any order until acceptance, as set forth below.
Once an order has been accepted, upon the next determination of the net asset value of the shares, a fund will confirm the issuance of a Creation Unit, against receipt of payment, at such net asset value. The transfer agent will then transmit a confirmation of acceptance to the Authorized Participant that placed the order.
Each fund reserves the absolute right to reject or revoke a creation order transmitted to it by the transfer agent if: (i) the order is not in proper form; (ii) the investor(s), upon obtaining the shares ordered, would own 80% or more of the currently outstanding shares of the fund; (iii) the Deposit Securities delivered do not conform to the identity and number of shares specified, as described above; (iv) acceptance of the Fund Deposit would have certain adverse tax consequences to the fund; (v) acceptance of the Fund Deposit would, in the opinion of the fund, be unlawful; (vi) acceptance of the Fund Deposit would, in the discretion of the fund or the advisor, have an adverse effect on the fund or the rights of beneficial owners; or (vii) circumstances outside the control of the fund make it impossible to process purchase orders for all practical purposes. The transfer agent shall notify a prospective purchaser of a Creation Unit and/or the Authorized Participant acting on behalf of such purchaser of its rejection of such order. The funds, the funds’ custodian, the sub-custodian and the distributor are under no duty, however, to give notification of any defects or irregularities in the delivery of Fund Deposits nor shall any of them incur any liability for failure to give such notification.
Issuance of a Creation Unit
Except as provided herein, a Creation Unit will not be issued until the transfer of good title to the fund of the Deposit Securities and the payment of the Cash Component have been completed. When the sub-custodian has confirmed to the custodian that the securities included in the Fund Deposit (or the cash value thereof) have been delivered to the account of the relevant sub-custodian or sub-custodians, the transfer agent and the advisor shall be notified of such delivery and the fund will issue and cause the delivery of the Creation Unit. Typically, Creation Units are issued on a “T+2 basis” (i.e., two Business Days after trade date). However, each fund reserves the right to settle Creation Unit transactions on a basis other than T+2 if necessary or appropriate under the circumstances.
To the extent contemplated by an Authorized Participant Agreement, the funds will issue Creation Units to an Authorized Participant, notwithstanding the fact that the corresponding Fund Deposits have not been received in part or in whole, in reliance on the undertaking of the Authorized Participant to deliver the missing Deposit Securities as soon as possible, which undertaking shall be secured by such Authorized Participant’s delivery and maintenance of collateral having a value at least equal to 105% and up to 115%, which percentage the trust may change at any time, in its sole discretion, of the value of the missing Deposit Securities in accordance with the fund’s then-effective procedures. The trust may use such cash deposit at any time to buy Deposit Securities for the fund. The only collateral that is acceptable to the funds is cash in U.S. dollars. Such cash collateral must be delivered no later than 1 p.m., Eastern time on the prescribed settlement date or such other time as designated by the funds’ custodian. Information concerning the funds’ current procedures for collateralization of missing Deposit Securities is available from the transfer agent. The Authorized Participant Agreement will permit the funds to buy the missing Deposit Securities at any time and will subject the Authorized Participant to liability for any shortfall between the cost to a fund of purchasing such securities and the value of the cash collateral including, without limitation, liability for related brokerage, borrowings and other charges.
In certain cases, Authorized Participants may create and redeem Creation Units on the same trade date and in these instances, a fund reserves the right to settle these transactions on a net basis or require a representation from the Authorized Participants that the creation and redemption transactions are for separate beneficial owners. All questions as to the number of shares of each security in the Deposit Securities and the validity, form, eligibility and acceptance for deposit of any securities to be delivered shall be determined by the funds and the funds’ determination shall be final and binding.

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Costs associated with creation transactions
A standard creation transaction fee is imposed to offset the transfer and other transaction costs associated with the issuance of Creation Units. The standard creation transaction fee is charged to the Authorized Participant on the day such Authorized Participant creates a Creation Unit, and is the same, regardless of the number of Creation Units purchased by the Authorized Participant on the applicable Business Day. The Authorized Participant may also be required to cover certain brokerage, tax, foreign exchange, execution, market impact and other costs and expenses related to the execution of trades resulting from such transaction (up to the maximum amount shown below). Authorized Participants will also bear the costs of transferring the Deposit Securities to a fund. Investors who use the services of a broker or other financial intermediary to acquire fund shares may be charged a fee for such services.
The following table sets forth each fund’s standard creation transaction fees and maximum additional charge (as described above). Transaction fees may be waived in certain circumstances deemed appropriate by the trust.
Fund
Standard Creation Transaction Fee
Maximum Additional Charge for Creations1
American Century STOXX® U.S. Quality Value ETF
$500
3%
American Century Diversified Corporate Bond ETF
$300
3%
1 As a percentage of the net asset value per Creation Unit.
Redemption of Creation Units    
Shares of the funds may be redeemed by Authorized Participants only in Creation Units at their NAV next determined after receipt of a redemption request in proper form by the transfer agent and only on a Business Day. The funds will not redeem shares in amounts less than Creation Units. There can be no assurance, however, that there will be sufficient liquidity in the secondary market at any time to permit assembly of a Creation Unit. Investors should expect to incur brokerage and other costs in connection with assembling a sufficient number of shares to constitute a Creation Unit that could be redeemed by an Authorized Participant. Beneficial owners also may sell shares in the secondary market. The funds generally redeem Creation Units for Fund Securities (as defined below) and the Cash Amount (as defined below). Please see the Cash Redemption Method section below and the following discussion summarizing the in-kind method for further information on redeeming Creation Units of the funds.
The advisor makes available through the NSCC, prior to the opening of business on the Listing Exchange on each Business Day, the designated portfolio of securities (including any portion of such securities for which cash may be substituted) that will be applicable (subject to possible amendment or correction) to redemption requests received in proper form (as defined below) on that day (Fund Securities), and an amount of cash as described below (Cash Amount) (if any). Such Fund Securities and the corresponding Cash Amount (each subject to possible amendment or correction) are applicable in order to effect redemptions of Creation Units of a fund until such time as the next announced composition of the Fund Securities and Cash Amount is made available. Fund Securities received on redemption may not be identical to Deposit Securities that are applicable to creations of Creation Units under certain circumstances.
Unless cash redemptions are available or specified for the funds, the redemption proceeds for a Creation Unit generally consist of Fund Securities, plus the Cash Amount, which is an amount equal to the difference between the net asset value of the shares being redeemed, as next determined after the receipt of a redemption request in proper form, and the value of Fund Securities, less a redemption transaction fee (as described below).
The funds may, in their sole discretion, substitute a “cash in lieu” amount to replace any Fund Security that may not be eligible for transfer through DTC Facilities or the NSCC Clearing Process or that the Authorized Participant is not able to trade due to a trading restriction. The funds also reserve the right to permit or require a “cash in lieu” amount in certain circumstances, including circumstances in which: (i) the delivery of a Fund Security to the Authorized Participant would be restricted under applicable securities or other local laws; (ii) the delivery of a Fund Security to the Authorized Participant would result in the disposition of the Fund Security by the Authorized Participant becoming restricted under applicable securities or other local laws; or (iii) in certain other situations. The amount of cash paid out in such cases will be equivalent to the value of the substituted security listed as a Fund Security. In the event that the Fund Securities have a value greater than the NAV of the shares, a compensating cash payment equal to the difference is required to be made by or through an Authorized Participant by the redeeming shareholder. The funds generally redeem Creation Units for Fund Securities and the Cash Amount, but the funds reserve the right to utilize a cash option for redemption of Creation Units.
Cash Redemption Method   
Although the trust does not ordinarily permit partial or full cash redemptions of Creation Units of the funds, when partial or full cash redemptions of Creation Units are available or specified for the fund, they will be effected in essentially the same manner as in-kind purchases thereof. In the case of a partial or full cash redemption, the Authorized Participant receives the cash equivalent of the Fund Securities it would otherwise receive through an in-kind redemption, plus the same Cash Amount to be paid to an in-kind redeemer.

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Costs Associated with Redemption Transactions    
A standard redemption transaction fee is imposed to offset transfer and other transaction costs that may be incurred by the funds. The standard redemption transaction fee is charged to the Authorized Participant on the day such Authorized Participant redeems a Creation Unit, and is the same regardless of the number of Creation Units redeemed by an Authorized Participant on the applicable Business Day. The Authorized Participant may also be required to cover certain brokerage, tax, foreign exchange, execution, market impact and other costs and expenses related to the execution of trades resulting from such transaction (up to the maximum amount shown below). Authorized Participants will also bear the costs of transferring the Fund Securities from a fund to their account on their order. Investors who use the services of a broker or other financial intermediary to dispose of fund shares may be charged a fee for such services.
The following table sets forth each fund’s standard redemption transaction fees and maximum additional charge (as described above). Transaction fees may be waived in certain circumstances deemed appropriate by the trust.
Fund
Standard Redemption Transaction Fee
Maximum Additional Charge for Redemptions1
American Century STOXX® U.S. Quality Value ETF
$500
2%
American Century Diversified Corporate Bond ETF
$300
2%
1 As a percentage of the net asset value per Creation Unit, inclusive of the standard redemption transaction fee.
Placement of Redemption Orders    
Redemption requests for Creation Units of the funds must be submitted to the transfer agent by or through an Authorized Participant. An Authorized Participant must submit an irrevocable request to redeem shares of a fund, in proper form, no later than the closing of the regular trading session of the Listing Exchange (normally 4 p.m., Eastern time), and with respect to the American Century Diversified Corporate Bond ETF no later than two hours prior to the closing time of the regular trading session (normally 2 p.m. Eastern time), on any Business Day, in order to receive that day’s NAV. On days when the Listing Exchange closes earlier than normal, a fund may require orders to redeem Creation Units to be placed earlier that day. Investors, other than Authorized Participants, are responsible for making arrangements for a redemption request to be made through an Authorized Participant.
The Authorized Participant must transmit the request for redemption in the form required by a fund to the transfer agent in accordance with procedures set forth in the Authorized Participant Agreement. Investors should be aware that their particular broker may not have executed an Authorized Participant Agreement and that, therefore, requests to redeem Creation Units may have to be placed by the investor’s broker through an Authorized Participant who has executed an Authorized Participant Agreement. At any time, only a limited number of broker-dealers will have an Authorized Participant Agreement in effect. Investors making a redemption request should be aware that such request must be in the form specified by such Authorized Participant. Investors making a request to redeem Creation Units should allow sufficient time to permit proper submission of the request by an Authorized Participant and transfer of the shares to a fund’s transfer agent; such investors should allow for the additional time that may be required to effect redemptions through their banks, brokers or other financial intermediaries if such intermediaries are not Authorized Participants.
A redemption request is considered to be in “proper form” if: (i) an Authorized Participant has transferred or caused to be transferred to a fund’s transfer agent the Creation Unit redeemed through the book-entry system of DTC so as to be effective by the Listing Exchange closing time on any Business Day; (ii) a request in form satisfactory to the fund is received by the transfer agent from the Authorized Participant on behalf of itself or another redeeming investor within the time periods specified above; and (iii) all other procedures set forth in the Authorized Participant Agreement are properly followed. If the transfer agent does not receive the investor’s shares through DTC Facilities by 10 a.m., Eastern time on the prescribed settlement date, the redemption request may be deemed rejected. Investors should be aware that the deadline for such transfers of shares through the DTC Facilities may be significantly earlier than the close of business on the Listing Exchange. Those making redemption requests should ascertain the deadline applicable to transfers of shares through the DTC Facilities by contacting the operations department of the broker or depositary institution effecting the transfer of the shares.
Upon receiving a redemption request, the transfer agent shall notify the fund and the fund’s transfer agent of such redemption request. The tender of an investor’s shares for redemption and the distribution of the securities and/or cash included in the redemption payment made in respect of Creation Units redeemed will be made through DTC and the relevant Authorized Participant to the Beneficial Owner thereof as recorded on the book-entry system of DTC or the DTC Participant through which such investor holds, as the case may be, or by such other means specified by the Authorized Participant submitting the redemption request.
A redeeming Beneficial Owner or Authorized Participant acting on behalf of such Beneficial Owner must maintain appropriate security arrangements with a qualified broker-dealer, bank or other custody providers in each jurisdiction in which any of the portfolio securities are customarily traded, to which account such portfolio securities will be delivered.

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Deliveries of redemption proceeds by a fund generally will be made within two Business Days (i.e., “T+2”). Each fund reserves the right to settle redemption transactions later than T+2 but by T+7 if necessary or appropriate under the circumstances and compliant with applicable law. Delayed settlement may occur due to a number of different reasons, including, without limitation, settlement cycles for the underlying securities, unscheduled market closings, an effort to link distribution to dividend record dates and ex-dates and newly announced holidays. For example, the redemption settlement process may be extended beyond T+2 because of the occurrence of a holiday in a non-U.S. market or in the U.S. bond market that is not a holiday observed in the U.S. equity market.
If neither the redeeming Beneficial Owner nor the Authorized Participant acting on behalf of such redeeming Beneficial Owner has appropriate arrangements to take delivery of Fund Securities in the applicable non-U.S. jurisdiction and it is not possible to make other such arrangements, or if it is not possible to effect deliveries of Fund Securities in such jurisdiction, the fund may in its discretion exercise its option to redeem such shares in cash, and the redeeming Beneficial Owner will be required to receive its redemption proceeds in cash. In such case, the investor will receive a cash payment equal to the net asset value of its shares based on the NAV of the fund next determined after the redemption request is received in proper form (minus a redemption transaction fee and additional charges specified above, to offset the fund’s brokerage and other transaction costs associated with the disposition of Fund Securities). Redemptions of shares for Fund Securities will be subject to compliance with applicable U.S. federal and state securities laws and the fund (whether or not it otherwise permits cash redemptions) reserves the right to redeem Creation Units for cash to the extent that the fund cannot lawfully deliver specific Fund Securities upon redemptions or cannot do so without first registering the Fund Securities under such laws.
In the event that cash redemptions are permitted or required by the trust, proceeds will be paid to the Authorized Participant redeeming shares as soon as practicable after the date of redemption (within seven calendar days thereafter).
To the extent contemplated by an Authorized Participant Agreement, in the event an Authorized Participant has submitted a redemption request in proper form but is unable to transfer all or part of the Creation Unit to be redeemed to a fund, at or prior to 10 a.m., Eastern time on the prescribed settlement date, the transfer agent will accept the redemption request in reliance on the undertaking by the Authorized Participant to deliver the missing shares as soon as possible. Such undertaking shall be secured by the Authorized Participant’s delivery and maintenance of collateral consisting of cash, in U.S. dollars in immediately available funds, having a value at least equal to 105% and up to 115%, which percentage the trust may change at any time, in its sole discretion, of the value of the missing shares. Such cash collateral must be delivered no later than 10 a.m., Eastern time on the prescribed settlement date and shall be held by the fund’s custodian and marked-to-market daily. The fees of the fund’s custodian and any sub-custodians in respect of the delivery, maintenance and redelivery of the cash collateral shall be payable by the Authorized Participant. The Authorized Participant Agreement will permit a fund to purchase missing fund shares or acquire the Deposit Securities and the Cash Amount underlying such shares, and will subject the Authorized Participant to liability for any shortfall between the cost of the fund acquiring such shares, the Deposit Securities or Cash Amount and the value of the cash collateral including, without limitation, liability for related brokerage and other charges.
Because the portfolio securities of a fund may trade on exchange(s) on days that the Listing Exchange is closed or are otherwise not Business Days for the fund, shareholders may not be able to redeem their shares of the fund, or purchase or sell shares of the fund on the Listing Exchange on days when the NAV of the fund could be significantly affected by events in the relevant non-U.S. markets.
The right of redemption may be suspended or the date of payment postponed with respect to a fund: (i) for any period during which the Listing Exchange is closed (other than customary weekend and holiday closings); (ii) for any period during which trading on the Listing Exchange is restricted; (iii) for any period during which an emergency exists as a result of which disposal of the shares of the fund’s portfolio securities or determination of its net asset value is not reasonably practicable; or (iv) in such other circumstances as is permitted by the SEC.
Service Providers
The funds have no employees. To conduct the funds’ day-to-day activities, the trust has hired a number of service providers. Each service provider has a specific function to fill on behalf of the funds that is described below.
ACIM and ACS are wholly owned, directly or indirectly, by ACC. The Stowers Institute for Medical Research (SIMR) controls ACC by virtue of its beneficial ownership of more than 25% of the voting securities of ACC. SIMR is part of a not-for-profit biomedical research organization dedicated to finding the keys to the causes, treatments and prevention of disease.
Investment Advisor
ACIM serves as the investment advisor for each of the funds. A description of the responsibilities of the advisor appears in each prospectus under the heading Management.
For services provided to each fund, the advisor receives a unified management fee based on a percentage of the daily net assets of each class of shares of the fund. For more information about the unified management fee, see The Investment Advisor under the

38



heading Management in each fund’s prospectus. The amount of the fee is calculated daily and paid monthly in arrears. The management fee schedules for the funds appear below.
Fund
Advisory Fee
American Century STOXX® U.S. Quality Value ETF
0.29%
American Century Diversified Corporate Bond ETF
0.45%
On each calendar day, each class of each fund accrues a management fee that is equal to the class’s management fee rate (as calculated pursuant to the above schedules) times the net assets of the class divided by 365 (366 in leap years). On the first business day of each month, the funds pay a management fee to the advisor for the previous month. The management fee is the sum of the daily fee calculations for each day of the previous month.
The management agreement between the trust and the advisor shall continue in effect for a period of two years from its effective date (unless sooner terminated in accordance with its terms) and shall continue in effect from year to year thereafter for each fund so long as such continuance is approved at least annually by:
(1)
either the funds’ Board of Trustees, or a majority of the outstanding voting securities of such fund (as defined in the Investment Company Act); and
(2)
the vote of a majority of the trustees of the funds who are not parties to the agreement or interested persons of the advisor, cast in person at a meeting called for the purpose of voting on such approval.
The management agreement states that the funds’ Board of Trustees or a majority of the outstanding voting securities of each class of such fund may terminate the management agreement at any time without payment of any penalty on 60 days’ written notice to the advisor. The management agreement shall be automatically terminated if it is assigned.
The management agreement states that the advisor shall not be liable to the funds or their shareholders for anything other than willful misfeasance, bad faith, gross negligence or reckless disregard of its obligations and duties.
The management agreement also provides that the advisor and its officers, trustees and employees may engage in other business, render services to others, and devote time and attention to any other business, whether of a similar or dissimilar nature.
Certain investments may be appropriate for the funds and also for other clients advised by the advisor. Investment decisions for the funds and other clients are made with a view to achieving their respective investment objectives after consideration of such factors as their current holdings, availability of cash for investment and the size of their investment generally. A particular security may be bought or sold for only one client or fund, or in different amounts and at different times for more than one but less than all clients or funds. A particular security may be bought for one client or fund on the same day it is sold for another client or fund, and a client or fund may hold a short position in a particular security at the same time another client or fund holds a long position. In addition, purchases or sales of the same security may be made for two or more clients or funds on the same date. The advisor has adopted procedures designed to ensure such transactions will be allocated among clients and funds in a manner believed by the advisor to be equitable to each. In some cases this procedure could have an adverse effect on the price or amount of the securities purchased or sold by a fund.
The advisor may aggregate purchase and sale orders of the funds with purchase and sale orders of its other clients when the advisor believes that such aggregation provides the best execution for the funds. The Board of Trustees has approved the policy of the advisor with respect to the aggregation of portfolio transactions. To the extent equity trades are aggregated, shares purchased or sold are generally allocated to the participating portfolios pro rata based on order size. The advisor will not aggregate portfolio transactions of the funds unless it believes such aggregation is consistent with its duty to seek best execution on behalf of the funds and the terms of the management agreement. The advisor receives no additional compensation or remuneration as a result of such aggregation.
Portfolio Managers
Accounts Managed
The portfolio managers are responsible for the day-to-day management of various accounts, as indicated by the following table. None of these accounts has an advisory fee based on the performance of the account.

39



Accounts Managed (As of August 31, 2017)
 
 
Registered Investment
Companies (e.g.,
American Century
Investments funds
and American
Century Investments -
subadvised funds)
Other Pooled
Investment
Vehicles (e.g.,
commingled
trusts and 529
education
savings plans)
Other Accounts
(e.g., separate
accounts and
corporate accounts
including incubation
strategies and
corporate money)
Kevin Akioka
Number of Accounts
12
3
4
 
Assets
$15.5 billion
$920.1 million
$452.3 million
Rene Casis1
Number of Accounts
0
0
0
 
Assets
0
0
0
Gavin Fleischman
Number of Accounts
10
2
0
 
Assets
$15.4 billion
$899.8 million
0
Jeffrey Houston
Number of Accounts
10
3
1
 
Assets
$16.5 billion
$1.1 billion
$818.5 million
Le Tran
Number of Accounts
2
0
0
 
Assets
$305.3 million
0
0
Peruvemba Satish
Number of Accounts
1
0
0
 
Assets
$16.6 million
0
0
1 Mr. Casis joined American Century on January 2, 2018.

Potential Conflicts of Interest
Certain conflicts of interest may arise in connection with the management of multiple portfolios. Potential conflicts include, for example, conflicts among investment strategies, such as one portfolio buying or selling a security while another portfolio has a differing, potentially opposite position in such security. This may include one portfolio taking a short position in the security of an issuer that is held long in another portfolio (or vice versa). Other potential conflicts may arise with respect to the allocation of investment opportunities, which are discussed in more detail below. American Century Investments has adopted policies and procedures that are designed to minimize the effects of these conflicts.
Responsibility for managing American Century Investments client portfolios is organized according to investment discipline. Investment disciplines include, for example, disciplined equity, global growth equity, global value equity, global fixed income and multi-asset strategies. Within each discipline are one or more portfolio teams responsible for managing specific client portfolios. Generally, client portfolios with similar strategies are managed by the same team using the same objective, approach, and philosophy. Accordingly, portfolio holdings, position sizes, and industry and sector exposures tend to be similar across similar portfolios, which minimizes the potential for conflicts of interest. In addition, American Century Investments maintains an ethical wall around each of its equity investment disciplines (global growth equity, global value equity and disciplined equity), meaning that access to information regarding any portfolio’s transactional activities is only available to team members of the investment discipline that manages such portfolio. The ethical wall is intended to aid in preventing the misuse of portfolio holdings information and trading activity in the other disciplines.
For each investment strategy, one portfolio is generally designated as the “policy portfolio.” Other portfolios with similar investment objectives, guidelines and restrictions, if any, are referred to as “tracking portfolios.” When managing policy and tracking portfolios, a portfolio team typically purchases and sells securities across all portfolios that the team manages. American Century Investments’ trading systems include various order entry programs that assist in the management of multiple portfolios, such as the ability to purchase or sell the same relative amount of one security across several funds. In some cases a tracking portfolio may have additional restrictions or limitations that cause it to be managed separately from the policy portfolio. Portfolio managers make purchase and sale decisions for such portfolios alongside the policy portfolio to the extent the overlap is appropriate, and separately, if the overlap is not.
American Century Investments may aggregate orders to purchase or sell the same security for multiple portfolios when it believes such aggregation is consistent with its duty to seek best execution on behalf of its clients. Orders of certain client portfolios may, by investment restriction or otherwise, be determined not available for aggregation. American Century Investments has adopted policies and procedures to minimize the risk that a client portfolio could be systematically advantaged or disadvantaged in connection with the aggregation of orders. To the extent equity trades are aggregated, shares purchased or sold are generally allocated to the participating portfolios pro rata based on order size. Because initial public offerings (IPOs) are usually available in limited supply and in amounts too small to permit across-the-board pro rata allocations, American Century Investments has

40



adopted special procedures designed to promote a fair and equitable allocation of IPO securities among clients over time. Fixed income securities transactions are not executed through a centralized trading desk. Instead, portfolio teams are responsible for executing trades with broker/dealers in a predominantly dealer marketplace. Trade allocation decisions are made by the portfolio manager at the time of trade execution and orders entered on the fixed income order management system.
Finally, investment of American Century Investments’ corporate assets in proprietary accounts may raise additional conflicts of interest. To mitigate these potential conflicts of interest, American Century Investments has adopted policies and procedures intended to provide that trading in proprietary accounts is performed in a manner that does not give improper advantage to American Century Investments to the detriment of client portfolios.
Compensation
American Century Investments portfolio manager compensation is structured to align the interests of portfolio managers with those of the shareholders whose assets they manage. As of the date of this SAI, it includes the components described below, each of which is determined with reference to a number of factors such as overall performance, market competition, and internal equity.
Base Salary
Portfolio managers receive base pay in the form of a fixed annual salary.
Bonus
A significant portion of portfolio manager compensation takes the form of an annual incentive bonus tied to performance. Bonus payments are determined by a combination of factors. One factor is fund investment performance. The funds’ investment performance is generally measured by a combination of one-, three- and five-year pre-tax performance relative to each fund’s benchmark. The performance comparison periods may be adjusted based on a fund’s inception date or a portfolio manager’s tenure on the fund.
Portfolio managers may have responsibility for multiple American Century Investments funds. In such cases, the performance of each is assigned a percentage weight appropriate for the portfolio manager’s relative levels of responsibility. Portfolio managers also may have responsibility for other types of similarly managed portfolios. If the performance of a similarly managed account is considered for purposes of compensation, it is measured in the same way as a comparable American Century Investments fund (i.e., relative to the performance of a benchmark and/or peer group).
A second factor in the bonus calculation relates to the performance of a number of American Century Investments funds managed according to one of the following investment disciplines: global growth equity, global value equity, global and non-U.S., disciplined equity, global fixed-income, and multi-asset strategies. Performance is measured for each product individually as described above and then combined to create an overall composite for the product group. These composites may measure one-year performance (equal weighted) or a combination of one-, three- and five-year performance (equal or asset weighted) depending on the portfolio manager’s responsibilities and products managed. This feature is designed to encourage effective teamwork among portfolio management teams in achieving long-term investment success for similarly styled portfolios. The American Century STOXX® U.S. Quality Value ETF is not included in a product group composite.
A portion of portfolio managers’ bonuses may be tied to individual performance goals, such as research projects and the development of new products.
Restricted Stock Plans
Portfolio managers are eligible for grants of restricted stock of ACC. These grants are discretionary, and eligibility and availability can vary from year to year. The size of an individual’s grant is determined by individual and product performance as well as other product-specific considerations such as profitability. Grants can appreciate/depreciate in value based on the performance of the ACC stock during the restriction period (generally three to four years).
Deferred Compensation Plans
Portfolio managers are eligible for grants of deferred compensation. These grants are used in very limited situations, primarily for retention purposes. Grants are fixed and can appreciate/depreciate in value based on the performance of the American Century Investments funds in which the portfolio manager chooses to invest them.
Ownership of Securities
As of the date of this SAI, neither fund has commenced investment operations; therefore none of the portfolio managers beneficially own any shares of the funds.
Transfer Agent
State Street Bank and Trust Company, a Massachusetts trust company (the transfer agent), 1 Heritage Drive, North Quincy, Massachusetts 02171, serves as transfer agent and dividend-paying agent for the funds under a Transfer Agency and Service Agreement with the funds. The transfer agent has undertaken to perform some or all of the following services: (i) perform and

41



facilitate the performance of purchases and redemptions of creation units; (ii) prepare and transmit payments for dividends and distributions; (iii) record the issuance of shares and maintain records of the number of authorized shares; (iv) prepare and transmit information regarding purchases and redemptions of shares; (v) maintain required books and records; and (vi) perform other customary services of a transfer agent and dividend disbursing agent for an exchange traded fund. Under its investment management agreement, the advisor has contractually assumed the funds’ obligation to pay the expenses of the transfer agent. For a description of this fee and the terms of its payment, see the above discussion under the caption Investment Advisor on page 38 .
Administrator
American Century Services, LLC (ACS), 4500 Main Street, Kansas City, Missouri 64111, serves as fund administrator for the funds. The administrator has undertaken to perform some or all of the following services: (i) providing office facilities and furnishing corporate officers for the trust; (ii) monitoring compliance with federal tax and securities law; (iii) performing certain functions ordinarily performed by the office of a corporate treasurer, and furnishing the services and facilities ordinarily incident thereto, such as expense accrual, monitoring and payment of the trust’s bills, preparing monthly reconciliation of the of the trust’s expense records, updating projections of annual expenses, preparing material for review by the Board of Trustees and compliance testing; (iv) maintaining the trust’s books and records in accordance with applicable statutes, rules and regulations; (vi) preparing post-effective amendments to the Trust’s registration statement; and (ix) preparing and filing the trust’s federal and state tax returns (other than those required to be filed by the trust’s custodian and transfer agent) and providing shareholder tax information to the trust’s transfer agent. The advisor has contractually assumed the funds’ obligation to pay the expenses of the administrator. For a description of this fee and the terms of its payment, see the above discussion under the caption Investment Advisor on page 38 .
Sub-Administrator
The advisor has entered into an Administration Agreement with State Street Bank and Trust Company (the sub-administrator) to provide certain fund accounting, fund financial reporting, tax and treasury/tax compliance services for the funds, including striking the daily net asset value for each fund. The advisor pays the sub-administrator a monthly fee as compensation for these services that is based on the total net assets of accounts in the American Century complex serviced by the sub-administrator. ACS does pay the sub-administrator for some additional services on a per fund basis.
Distributor
Foreside Fund Services, LLC (the distributor) is the distributor (also known as principal underwriter) of the shares of the funds and is located at Three Canal Plaza, Suite 100, Portland, Maine 04101. The distributor is a registered broker-dealer and is a member of the Financial Industry Regulatory Authority, Inc. (FINRA). The distributor is not affiliated with the advisor or its affiliates.
Shares are continuously offered for sale by the funds through the distributor only in Creation Units as described in each fund’s prospectus and above in Creation and Redemption of Creation Units. Fund shares in amounts less than Creation Units are generally not distributed by the distributor. The distributor will arrange for the delivery of the prospectus and, upon request, this SAI to Authorized Participants that have entered into an Authorized Participation Agreement with the distributor.
The advisor pays the distributor a fee for serving as principal underwriter of the funds’ shares out of the advisor’s unified management fee. For a description of this fee and the terms of its payment, see the above discussion under the caption Investment Advisor on page 38 . The distributor does not earn commissions for distributing the funds’ shares.
Certain financial intermediaries unaffiliated with the distributor or the funds may perform various administrative and shareholder services for their clients who are invested in the funds. These services may include assisting with fund purchases and redemptions, distributing information about the funds and their performance, preparing and distributing client account statements, and other administrative and shareholder services.
Distribution and service (12b-1) fees
The board has adopted a plan pursuant to Rule 12b-1 for the funds. However, no Rule 12b-1 plan fee is currently charged to the funds, and there are no plans in place to impose a Rule 12b-1 plan fee. The plan is designed to benefit each fund and its shareholders. The plan is expected to, among other things, increase advertising of the funds, encourage purchases of fund shares and service to its shareholders, and increase or maintain assets of the funds so that certain fixed expenses may be spread over a broader asset base, with a positive impact on per share expense ratios. In addition, a positive cash flow into the fund is useful in managing the fund because the advisor has more flexibility in taking advantage of new investment opportunities and handling shareholder redemptions.
Under the plan, the funds pays the distributor or others for the expenses of activities that are primarily intended to sell shares of the funds. These expenses also may include service fees paid to securities dealers or others who have executed a servicing agreement with a fund, the distributor or its affiliates and who provide service or account maintenance to shareholders (service fees); and the expenses of printing prospectuses and reports used for sales purposes, of marketing support and of preparing and distributing sales literature and advertisements. Together, these expenses, including the service fees, are “eligible expenses.”
In addition to the payments that the distributor or others are entitled to under the plan, the plan also provides that to the extent a fund, the advisor or the distributor or other parties on behalf of the fund, the advisor or the distributor make payments that are

42



deemed to be for the financing of any activity primarily intended to result in the sale of fund shares within the context of Rule 12b-1 under the 1940 Act, then such payments shall be deemed to have been made pursuant to the plan.
To the extent fees are for distribution or marketing functions, as distinguished from administrative servicing or agency transactions, certain banks may not participate in the plan because of applicable federal law prohibiting certain banks from engaging in the distribution of fund shares. These banks, however, are allowed to receive fees under the plans for administrative servicing or for agency transactions.
The distributor must provide written reports to the board at least quarterly on the amounts and purpose of any payment made under the plans and any related agreements, and furnish the board with such other information as the board may reasonably request to enable it to make an informed determination of whether the plan should be continued.
The plan has been approved according to the provisions of Rule 12b-1. The terms and provisions of the plan also are consistent with Rule 12b-1.
Custodian Bank
State Street Bank and Trust Company (the custodian), State Street Financial Center, One Lincoln Street, Boston, Massachusetts 02111 serves as custodian of the funds’ cash and securities under a Master Custodian Agreement. Foreign securities, if any, are held by foreign banks participating in a network coordinated by the custodian. The custodian takes no part in determining the investment policies of the funds or in deciding which securities are purchased or sold by the funds. The funds, however, may invest in certain obligations of the custodian and may purchase or sell certain securities from or to the custodian.
Independent Registered Public Accounting Firm
Deloitte & Touche LLP is the independent registered public accounting firm of the funds. The address of Deloitte & Touche LLP is 1100 Walnut Street, Kansas City, Missouri 64106. As the independent registered public accounting firm of the funds, Deloitte & Touche LLP provides services including auditing the annual financial statements and financial highlights for each fund.
Brokerage Allocation
The advisor places orders for equity portfolio transactions with broker-dealers, who receive commissions for their services. Generally, commissions relating to securities traded on foreign exchanges will be higher than commissions relating to securities traded on U.S. exchanges. The advisor purchases and sells fixed-income securities through principal transactions, meaning the advisor normally purchases securities on a net basis directly from the issuer or a primary market-maker acting as principal for the securities. The funds generally do not pay a stated brokerage commission on these transactions, although the purchase price for debt securities usually includes an undisclosed compensation. Purchases of securities from underwriters typically include a commission or concession paid by the issuer to the underwriter, and purchases from dealers serving as market-makers typically include a dealer’s mark-up (i.e., a spread between the bid and asked prices).
Under the management agreement between the funds and the advisor, the advisor has the responsibility of selecting brokers and dealers to execute portfolio transactions. The funds’ policy is to secure the most favorable prices and execution of orders on its portfolio transactions. The advisor selects broker-dealers on their perceived ability to obtain “best execution” in effecting transactions in its clients’ portfolios. In selecting broker-dealers to effect portfolio transactions relating to equity securities, the advisor considers the full range and quality of a broker-dealer’s research and brokerage services, including, but not limited to, the following:
applicable commission rates and other transaction costs charged by the broker-dealer
value of research provided to the advisor by the broker-dealer (including economic forecasts, fundamental and technical advice on individual securities, market analysis, and advice, either directly or through publications or writings, as to the value of securities, availability of securities or of purchasers/sellers of securities)
timeliness of the broker-dealer’s trade executions
efficiency and accuracy of the broker-dealer’s clearance and settlement processes
broker-dealer’s ability to provide data on securities executions
financial condition of the broker-dealer
the quality of the overall brokerage and customer service provided by the broker-dealer
In transactions to buy and sell fixed-income securities, the selection of the broker-dealer is determined by the availability of the desired security and its offering price, as well as the broker-dealer’s general execution and operational and financial capabilities in the type of transaction involved. The advisor will seek to obtain prompt execution of orders at the most favorable prices or yields. The advisor does not consider the receipt of products or services other than brokerage or research services in selecting broker-dealers.
On an ongoing basis, the advisor seeks to determine what levels of commission rates are reasonable in the marketplace. In evaluating the reasonableness of commission rates, the advisor considers:

43



rates quoted by broker-dealers
the size of a particular transaction, in terms of the number of shares, dollar amount, and number of clients involved
the ability of a broker-dealer to execute large trades while minimizing market impact
the complexity of a particular transaction
the nature and character of the markets on which a particular trade takes place
the level and type of business done with a particular firm over a period of time
the ability of a broker-dealer to provide anonymity while executing trades
historical commission rates
rates that other institutional investors are paying, based on publicly available information
The brokerage commissions paid by the funds may exceed those that another broker-dealer might have charged for effecting the same transactions, because of the value of the brokerage and research services provided by the broker-dealer. Research services furnished by broker-dealers through whom the funds effect securities transactions may be used by the advisor in servicing all of its accounts, and not all such services may be used by the advisor in managing the portfolios of the funds.
Pursuant to its internal allocation procedures, the advisor regularly evaluates the brokerage and research services provided by each broker-dealer that it uses. On a semi-annual basis, each member of the advisor’s portfolio management team rates the quality of research and brokerage services provided by each broker-dealer that provides execution services and research to the advisor for its clients’ accounts. The resulting scores are used to rank these broker-dealers on a broker research list. In the event that the advisor has determined that best execution for a particular transaction may be obtained by more than one broker-dealer, the advisor may consider the relative positions of the broker-dealer on this list in determining the party through which to execute the transaction. Actual business received by any firm may be more or less than other broker-dealers with a similar rank. Execution-only brokers are used where deemed appropriate.

Information About Fund Shares
Each of the funds named on the front of this statement of additional information is a series of shares issued by the trust, and shares of each fund have equal voting rights. In addition, each series (or fund) may be divided into separate classes. Additional funds and classes may be added without a shareholder vote. Each fund votes separately on matters affecting that fund exclusively. Voting rights are not cumulative, so that investors holding more than 50% of the trust’s (all funds’) outstanding shares may be able to elect a Board of Trustees. The trust undertakes dollar-based voting, meaning that the number of votes a shareholder is entitled to is based upon the dollar amount of the shareholder’s investment. The election of trustees is determined by the votes received from all the trust’s shareholders without regard to whether a majority of shares of any one fund voted in favor of a particular nominee or all nominees as a group.
The assets belonging to each series are held separately by the custodian, and the shares of each series represent a beneficial interest in the principal, earnings and profit (or losses) of investments and other assets held for each series. Within their respective series, all shares have equal redemption rights. Each share, when issued, is fully paid and non-assessable.
Each shareholder has rights to dividends and distributions declared by the fund he or she owns and to the net assets of such fund upon its liquidation or dissolution proportionate to his or her share ownership interest in the fund.
Valuation of a Fund’s Securities
The net asset value (NAV) for each class of each fund is calculated by adding the value of all portfolio securities and other assets attributable to the class, deducting liabilities, and dividing the result by the number of shares of the class outstanding. Expenses and interest earned on portfolio securities are accrued daily.
Each fund’s NAV is calculated as of the close of business of the New York Stock Exchange (the NYSE), each day the NYSE is open for business. The NYSE usually closes at 4 p.m. Eastern time. The NYSE typically observes the following holidays: New Year’s Day, Martin Luther King Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day. Although the funds expect the same holidays to be observed in the future, the NYSE may modify its holiday schedule at any time.
The funds value portfolio securities for which market quotations are readily available at their market price. As a general rule, equity securities listed on a U.S. exchange are valued at the last reported sale price as of the time of valuation. Portfolio securities primarily traded on foreign securities exchanges are generally valued at the preceding official close price or last sale price of such securities on the foreign exchange where primarily traded or at the time the fund’s NAV is determined, if that foreign exchange is open later than the NYSE. The value of any security or other asset denominated in a currency other than U.S. dollars is then converted to U.S. dollars at the prevailing foreign exchange rate at the time the fund’s NAV is determined. Securities that are neither listed on a securities exchange or traded over the counter may be priced using the mean of the bid and asked prices

44



obtained from an independent broker who is an established market maker in the security. The fund may use third party pricing services to assist in the determination of market value.  When market quotations are not readily available, securities and other assets are valued at fair value as determined according to procedures adopted by the Board of Trustees.
Debt securities not traded on a principal securities exchange are valued through valuations obtained from a commercial pricing service or at the most recent mean of the bid and asked prices provided by investment dealers according to procedures established by the Board of Trustees.
Securities maturing within 60 days of the valuation date may be valued at cost, plus or minus any amortized discount or premium, unless the trustees determine that this would not result in fair valuation of a given security. Other assets and securities for which quotations are not readily available are valued in good faith using methods approved by the Board of Trustees.
Trading in securities on European and Far Eastern securities exchanges and over-the-counter markets is normally completed at various times before the close of business on each day that the NYSE is open. If an event were to occur after the value of a security was established, but before the NAV was determined, that was likely to materially change the NAV, then that security would be valued as determined according to procedures adopted by the Board of Trustees.
Trading of these securities in foreign markets may not take place on every day that the NYSE is open. In addition, trading may take place in various foreign markets and on some electronic trading networks on Saturdays or on other days when the NYSE is not open and on which the funds’ NAVs are not calculated. Therefore, these calculations do not take place contemporaneously with the determination of the prices of many of the portfolio securities used in such calculation, and the value of the funds’ portfolios may be affected on days when shares of the funds may not be purchased or redeemed.
Taxes
Federal Income Taxes
Each fund intends to qualify annually as a regulated investment company (RIC) under Subchapter M of the Internal Revenue Code of 1986, as amended (the Code). RICs generally are not subject to federal and state income taxes. To qualify as a RIC a fund must, among other requirements, distribute substantially all of its net investment income and net realized capital gains (if any) to investors each year. If a fund were not eligible to be treated as a RIC, it would be liable for taxes at the fund level on all of its income, significantly reducing its distributions to investors and eliminating investors’ ability to treat distributions received from the fund in the same manner in which they were realized by the fund. Under certain circumstances, the Code allows funds to cure deficiencies that would otherwise result in the loss of RIC status, including by paying a fund-level tax.
To qualify as a RIC, a fund must meet certain requirements of the Code, among which are requirements relating to sources of its income and diversification of its assets. A fund is also required to distribute 90% of its investment company taxable income each year. Additionally, a fund must declare dividends by December 31 of each year equal to at least 98% of ordinary income (as of December 31) and 98.2% of capital gains (as of October 31) to avoid the nondeductible 4% federal excise tax on any undistributed amounts.
Certain bonds purchased by the funds may be treated as bonds that were originally issued at a discount. Original issue discount represents interest for federal income tax purposes and can generally be defined as the difference between the price at which a security was issued and its stated redemption price at maturity. Although no cash is actually received by a fund until the maturity of the bond, original issue discount is treated for federal income tax purposes as income earned by a fund over the term of the bond, and therefore is subject to the distribution requirements of the Code. The annual amount of income earned on such a bond by a fund generally is determined on the basis of a constant yield to maturity that takes into account the semiannual compounding of accrued interest.
In addition, some of the bonds may be purchased by a fund at a discount that exceeds the original issue discount on such bonds, if any. This additional discount represents market discount for federal income tax purposes. The gain realized on the disposition of any bond having market discount generally will be treated as taxable ordinary income to the extent it does not exceed the accrued market discount on such bond (unless a fund elects to include market discount in income in tax years to which it is attributable or if the amount is considered de minimis). Generally, market discount accrues on a daily basis for each day the bond is held by a fund on a constant yield to maturity basis. In the case of any debt security having a fixed maturity date of not more than one year from date of issue, the gain realized on disposition generally will be treated as a short-term capital gain. If a fund holds the foregoing kinds of securities, it may be required to pay out as an income distribution each year an amount that is greater than the total amount of cash interest the fund actually received, which distributions may be made from the assets of the fund or, if necessary, by disposition of portfolio securities, including at a time when such disposition may not otherwise be advantageous.
Investments in lower-rated securities may present special tax issues for the funds to the extent actual or anticipated defaults may be more likely with respect to these types of securities. Tax rules are not entirely clear about issues such as whether and to what extent a fund should recognize market discount on such a debt obligation, when a fund may cease to accrue interest, original issue discount or market discount, when and to what extent a fund may take deductions for bad debts or worthless securities and how a fund should allocate payments received on obligations in default between principal and income.

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A fund’s transactions in foreign currencies, forward contracts, options, futures contracts (including options and futures contracts on foreign currencies), swaps and short sales will be subject to special provisions of the Code that, among other things, may affect the character of gains and losses realized by the fund (i.e., may affect whether gains or losses are ordinary or capital), accelerate recognition of income to the fund, defer fund losses or accelerate fund gains, and affect the determination of whether capital gains and losses are characterized as long-term or short-term capital gains or losses. These rules could therefore affect the character, amount and timing of distributions to shareholders. These provisions also may require a fund to mark-to-market certain types of the positions in its portfolio (i.e., treat them as if they were sold), which may cause the fund to recognize income without receiving cash with which to make distributions in amounts necessary to satisfy the distribution requirements of the Code for relief from income and excise taxes. A fund will monitor its transactions and may make such tax elections as fund management deems appropriate with respect to these transactions.
A fund’s investments in foreign securities may be subject to withholding and other taxes imposed by foreign countries. However, tax conventions between certain countries and the United States may reduce or eliminate such taxes. Any foreign taxes paid by a fund will reduce its dividend distributions to investors.
If a fund purchases the securities of certain foreign investment entities called passive foreign investment companies (PFIC), capital gains on the sale of those holdings will be deemed ordinary income regardless of how long the fund holds the investment. The fund also may be subject to corporate income tax and an interest charge on certain dividends and capital gains earned from these investments, regardless of whether such income and gains are distributed to the fund.  To avoid such tax and interest, the fund may elect to treat PFICs as sold on the last day of its fiscal year, mark-to-market these securities, and recognize any unrealized gains (or losses, to the extent of previously recognized gains) as ordinary income each year.
A fund’s investment in ETFs could affect the amount, timing and character of distributions from the funds, and therefore may increase the amount of taxes payable by shareholders.
When a fund has a capital loss carryover, it does not make capital gains distributions until the loss has been offset. The amount of capital losses that can be carried forward and used in any single year is subject to an annual limitation if there is a more than 50% “change in ownership” of the fund. An ownership change generally results when shareholders owning 5% or more of the fund increase their aggregate holdings by more than 50% over a three-year lookback period. An ownership change could result in capital loss carryovers being used at a slower rate, thereby reducing the fund’s ability to offset capital gains with those losses.
If you have not complied with certain provisions of the Internal Revenue Code and Regulations, either American Century Investments or your financial intermediary is required by federal law to withhold and remit to the IRS the applicable federal withholding rate on reportable payments (which may include dividends, capital gains distributions and redemption proceeds). Those regulations require you to certify that the Social Security number or tax identification number you provide is correct and that you are not subject to withholding for previous under-reporting to the IRS. You will be asked to make the appropriate certification on your account application. Payments reported by us to the IRS that omit your Social Security number or tax identification number will subject us to a non-refundable penalty of $50, which will be charged against your account if you fail to provide the certification by the time the report is filed.
If fund shares are purchased through taxable accounts, distributions either of cash or additional shares of net investment income and net short-term capital gains are taxable to you as ordinary income, unless they are designated as qualified dividend income and you meet a minimum required holding period with respect to your shares of a fund, in which case such distributions are taxed at the same rate as long-term capital gains. Qualified dividend income is a dividend received by a fund from the stock of a domestic or qualifying foreign corporation, provided that the fund has held the stock for a required holding period. The required holding period for qualified dividend income is met if the underlying shares are held more than 60 days in the 121-day period beginning 60 days prior to the ex-dividend date. Dividends received by the funds on shares of stock of domestic corporations may qualify for the 70% dividends received deduction when distributed to corporate shareholders to the extent that the fund held those shares for more than 45 days.
Distributions from gains on assets held by a fund longer than 12 months are taxable as long-term gains regardless of the length of time you have held your shares in the fund. If you purchase shares in the fund and sell them at a loss within six months, your loss on the sale of those shares will be treated as a long-term capital loss to the extent of any long-term capital gains dividend you received on those shares.
Each fund may use the “equalization method” of accounting to allocate a portion of its earnings and profits to redemption proceeds. Although using this method generally will not affect a fund’s total returns, it may reduce the amount that a fund would otherwise distribute to continuing shareholders by reducing the effect of redemptions of fund shares on fund distributions to shareholders.
A redemption of shares of a fund will be a taxable transaction for federal income tax purposes, and you generally will recognize gain or loss in an amount equal to the difference between the basis of the shares and the amount received. If a loss is realized on the redemption of fund shares, the reinvestment in additional fund shares within 30 days before or after the redemption may be subject to the “wash sale” rules of the Code, postponing the recognition of such loss for federal income tax purposes.

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A 3.8% Medicare contribution tax is imposed on net investment income, including interest, dividends and capital gains, provided you meet specified income levels.
Creations and Redemptions of Creation Units
An Authorized Participant who exchanges securities for Creation Units generally will recognize a gain or a loss. The gain or loss will be equal to the difference between the market value of the Creation Units at the time and the sum of the exchanger’s aggregate basis in the securities surrendered plus the amount of cash paid for such Creation Units. A person who redeems Creation Units will generally recognize a gain or loss equal to the difference between the exchanger’s basis in the Creation Units and the sum of the aggregate market value of any securities received plus the amount of any cash received for such Creation Units. The IRS, however, may assert that a loss realized upon an exchange of securities for Creation Units cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in economic position.
Any capital gain or loss realized upon the creation of Creation Units will generally be treated as long-term capital gain or loss if the securities exchanged for such Creation Units have been held for more than one year. Any capital gain or loss realized upon the redemption of Creation Units will generally be treated as long-term capital gain or loss if the shares comprising the Creation Units have been held for more than one year. Otherwise, such capital gains or losses will generally be treated as short-term capital gain or loss. Any loss upon a redemption of Creation Units held for six (6) months or less will be treated as a long-term capital loss to the extent of any amounts treated as distributions to the applicable Authorized Participant of long-term capital gain with respect to the Creation Units (including any amounts credited to the Authorized Participant as undistributed capital gains).
The funds have the right to reject an order for Creation Units if the purchaser (or group of purchasers) would, upon obtaining the shares so ordered, own 80% or more of the outstanding shares of a fund and if, pursuant to sections 351 and 362 of the Code, the fund would have a basis in the deposit securities different from the market value of such securities on the date of deposit. A fund also has the right to require information necessary to determine beneficial share ownership for purposes of the 80% determination. If a fund does issue Creation Units to a purchaser (or group of purchasers) that would, upon obtaining the Shares so ordered, own 80% or more of the outstanding shares of the fund, the purchaser (or group of purchasers) may not recognize gain or loss upon the exchange of securities for Creation Units.
If a fund redeems Creation Units in cash, it may recognize more capital gains than it will if it redeems Creation Units in-kind.
State and Local Taxes
Distributions by the funds also may be subject to state and local taxes, even if all or a substantial part of those distributions are derived from interest on U.S. government obligations which, if you received such interest directly, would be exempt from state income tax. However, most, but not all, states allow this tax exemption to pass through to fund shareholders when a fund pays distributions to its shareholders. You should consult your tax advisor about the tax status of these distributions in your own state.
The information above is only a summary of some of the tax considerations affecting the funds and their U.S. shareholders. No attempt has been made to discuss individual tax consequences. A prospective investor should consult with his or her tax advisors or state or local tax authorities to determine whether the funds are suitable investments.

Financial Statements
The Statement of Assets and Liabilities as of December 21, 2017, as described in the Report of Independent Registered Public Accounting Firm, has been audited by Deloitte & Touche LLP.

Report of Independent Registered Public Accounting Firm
To the shareholders and the Board of Trustees of American Century ETF Trust:
Opinion on the Financial Statements and Financial Highlights
We have audited the accompanying statements of assets and liabilities of American Century ETF Trust (the "Funds") comprising the American Century STOXX ® U.S. Quality Value ETF and American Century Diversified Corporate Bond ETF, as of December 21, 2017, and the related notes. In our opinion, the financial statements present fairly, in all material respects, the financial position of each of the portfolios constituting the American Century ETF Trust as of December 21, 2017, in conformity with accounting principles generally accepted in the United States of America.
Basis for Opinion
These financial statements are the responsibility of the Funds’ management. Our responsibility is to express an opinion on the Funds’ financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting

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Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Funds in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.
We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Funds are not required to have, nor were we engaged to perform, an audit of their internal control over financial reporting. As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Funds’ internal control over financial reporting. Accordingly, we express no such opinion.
Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Deloitte & Touche LLP
Kansas City, Missouri
January 5, 2018
We have served as the auditor of one or more American Century investment companies since 1997.

American Century ETF Trust
Statement of Assets and Liabilities
DECEMBER 21, 2017
 
 
 
STOXX® U.S. Quality Value ETF
Diversified Corporate Bond ETF
Assets
 
 
Cash
$
40

$
100,000

 
 
 
Net Assets
$
40

$
100,000

 
 
 
 
 
 
Capital Shares
 
 
Shares outstanding (unlimited number of shares authorized)
1

2,000

 
 
 
Net Asset Value Per Share
$40.00
$50.00

Notes to Financial Statements
DECEMBER 21, 2017

1. Organization
American Century ETF Trust (the trust) was registered as a Delaware statutory trust in 2017 and is registered under the Investment Company Act of 1940, as amended (the 1940 Act), as an open-end management investment company. American Century STOXX ® U.S. Quality Value ETF (STOXX ® U.S. Quality Value ETF) and American Century Diversified Corporate Bond ETF (Diversified Corporate Bond ETF) (collectively, the funds) are two funds in a series issued by the trust. The funds have had no operations other than matters relating to organization and registration and the sale of their shares to American Century Investment Management, Inc. (ACIM). STOXX ® U.S. Quality Value ETF's investment objective is to seek to provide investment results that closely correspond, before fees and expenses, to the performance of the iSTOXX ® American Century USA Quality Value Index. Diversified Corporate Bond ETF's investment objective is to seek to provide current income.

2. Significant Accounting Policies

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The funds are investment companies and follow accounting and reporting guidance in accordance with accounting principles generally accepted in the United States of America. This may require management to make certain estimates and assumptions at the date of the financial statements. Actual results could differ from these estimates. The organization costs of the funds will be borne by ACIM. The funds intend to distribute substantially all net investment income and net realized gains to shareholders and to otherwise qualify as a regulated investment company under provisions of the Internal Revenue Code. Accordingly, no provision has been made for income taxes.

3. Fees and Transactions with Related Parties
Certain officers and trustees of the trust are also officers and/or directors of ACC. The trust's investment advisor, ACIM, and the trust's administrator, American Century Services, LLC, are wholly owned, directly or indirectly, by ACC.

Management Fees — The trust has entered into a management agreement with ACIM, under which ACIM provides the funds with investment advisory and management services in exchange for a single, unified management fee (the fee) . The agreement provides that all expenses of managing and operating the funds, other than the management fee payable to the advisor, brokerage and other transaction fees and expenses relating to the acquisition and disposition of portfolio securities, acquired fund fees and expenses, interest, taxes, litigation expenses, extraordinary expenses and expenses incurred in connection with the provision of shareholder and distribution services under a plan adopted pursuant to Rule 12b-1 under the 1940 Act, if any, will be paid by ACIM. The fee is computed and accrued daily based on each fund's daily net assets and paid monthly in arrears.

The annual management fee for each fund is as follows:
STOXX® U.S. Quality Value ETF
Diversified Corporate Bond ETF
0.29%
0.45%




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Appendix A - Explanation of Fixed-Income Securities Ratings
As described in the prospectuses, the funds invest in fixed-income securities. Those investments, however, are subject to certain credit quality restrictions, as noted in the prospectuses and in this statement of additional information. The following is a summary of the rating categories referenced in the prospectus disclosure.
Ratings of Corporate Debt Securities
Standard & Poor’s Long-Term Issue Credit Ratings*
Category
Definition
AAA
An obligation rated ‘AAA’ has the highest rating assigned by Standard & Poor’s. The obligor’s capacity to meet its financial commitment on the obligation is extremely strong.
AA
An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitment on the obligation is very strong.
A
An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitment on the obligation is still strong.
BBB
An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to lead to a weakened capacity of the obligor to meet its financial commitment on the obligation.
BB;B; CCC; CC; and C
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposures to adverse conditions.
BB
An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions which could lead to the obligor’s inadequate capacity to meet its financial commitment on the obligation.
B
An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitment on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitment on the obligation.
CCC
An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitment on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitment on the obligation.
CC
An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but Standard & Poor’s expects default to be a virtual certainty, regardless of the anticipated time to default.
C
An obligation rated ‘C’ is currently highly vulnerable to nonpayment,and the obligation is expected to have lower relative seniority or lower ultimate recovery compared to obligations that are rated higher.
D
An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless Standard & Poor’s believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. An obligation’s rating is lowered to ‘D’ if it is subject to a distressed exchange offer.
NR
This indicates that no rating has been requested, or that there is insufficient information on which to base a rating, or that Standard & Poor’s does not rate a particular obligation as a matter of policy.
*The ratings from “AA” to “CCC” may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the major rating categories.

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Moody’s Investors Service, Inc. Global Long-Term Rating Scale
Category
Aaa
Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa
Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A
Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa
Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba
Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B
Obligations rated B are considered speculative and are subject to high credit risk.
Caa
Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca
Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C
Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Note: Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The
modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a
mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a
“(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities
firms.

Fitch Investors Service, Inc. Long-Term Ratings
Category
AAA
Highest credit quality. ‘AAA’ ratings denote the lowest expectation of credit risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA
High credit quality. ‘A’ ratings denote expectations of low credit risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
A
High credit quality. ‘A’ ratings denote expectations of low credit risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB
Good credit quality. ‘BBB’ ratings indicate that expectations of credit risk are currently low. The capacity for payment of financial commitments is considered adequate but adverse business or economic conditions are more likely to impair this capacity.
BB
Speculative. ‘BB’ ratings indicate an elevated vulnerability to credit risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial alternatives may be available to allow financial commitments to be met.
B
Highly speculative. ‘B’ ratings indicate that material credit risk is present.
CCC
Substantial credit risk. ‘CCC’ ratings indicate that substantial credit risk is present.
CC
Very high levels of credit risk. ‘CC’ ratings indicate very high levels of credit risk.
C
Exceptionally high levels of credit risk. ‘C’ indicates exceptionally high levels of credit risk.
Defaulted obligations typically are not assigned ‘RD’ or ‘D’ ratings, but are instead rated in the ‘B’ to ‘C’ rating categories, depending upon their recovery prospects and other relevant characteristics. This approach better aligns obligations that have comparable overall expected loss but varying vulnerability to default and loss.
Notes: The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. Such suffixes are not added to the ‘AAA’ obligation rating category, or to corporate finance obligation ratings in the categories below ‘CCC’.

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Standard & Poor’s Corporate Short-Term Note Ratings
Category
A-1
A short-term obligation rated ‘A-1’ is rated in the highest category by Standard & Poor’s. The obligor’s capacity to meet its financial commitment on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitment on these obligations is extremely strong.
A-2
A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitment on the obligation is satisfactory.
A-3
A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to lead to a weakened capacity of the obligor to meet its financial commitment on the obligation.
B
A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties which could lead to the obligor’s inadequate capacity to meet its financial commitments.
C
A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitment on the obligation.
D
A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless Standard & Poor’s believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. An obligation’s rating is lowered to ‘D’ if it is subject to a distressed exchange offer.

Moody’s Global Short-Term Rating Scale
Category
P-1
Issuers (or supporting institutions) rated Prime-1 have a superior ability to repay short-term debt obligations.
P-2
Issuers (or supporting institutions) rated Prime-2 have a strong ability to repay short-term debt obligations.
P-3
Issuers (or supporting institutions) rated Prime-3 have an acceptable ability to repay short-term obligations.
NP
Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.

Fitch Investors Service, Inc. Short-Term Ratings
Category
F1
Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.
F2
Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3
Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B
Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C
High short-term default risk. Default is a real possibility.
RD
Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D
Default Indicates a broad-based default event for an entity, or the default of a short-term obligation.


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Standard & Poor’s Municipal Short-Term Note Ratings
Category
SP-1
Strong capacity to pay principal and interest. An issue determined to possess a very strong capacity to pay debt service is given a plus (+) designation.
SP-2
Satisfactory capacity to pay principal and interest, with some vulnerability to adverse financial and economic changes over the term of the notes.
SP-3
Speculative capacity to pay principal and interest.


Moody’s US Municipal Short-Term Debt Ratings
Category
MIG 1
This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2
This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3
This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG
This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.

Moody’s Demand Obligation Ratings
Category
VMIG 1
This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2
This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3
This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG
This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have an investment grade short-term rating or may lack the structural and/or legal protections necessary to ensure the timely payment of purchase price upon demand.



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Appendix B - Proxy Voting Policies
American Century Investment Management, Inc. (the “Advisor”) is the investment manager for a variety of advisory clients, including the American Century family of funds. In such capacity, the Advisor has been delegated the authority to vote proxies with respect to investments held in the accounts it manages. The following is a statement of the proxy voting policies that have been adopted by the Advisor. In the exercise of proxy voting authority which has been delegated to it by particular clients, the Advisor will apply the following policies in accordance with, and subject to, any specific policies that have been adopted by the client and communicated to and accepted by the Advisor in writing.
A.
General Principles
In providing the service of voting client proxies, the Advisor is guided by general fiduciary principles, must act prudently, solely in the interest of its clients, and must not subordinate client interests to unrelated objectives. Except as otherwise indicated in these Policies, the Advisor will vote all proxies with respect to investments held in the client accounts it manages. The Advisor will attempt to consider all factors of its vote that could affect the value of the investment. Although in most instances the Advisor will vote proxies consistently across all client accounts, the votes will be based on the best interests of each client. As a result, accounts managed by the Advisor may at times vote differently on the same proposals. Examples of when an account’s vote might differ from other accounts managed by the Advisor include, but are not limited to, proxy contests and proposed mergers. In short, the Advisor will vote proxies in the manner that it believes will do the most to maximize shareholder value.
B.
Specific Proxy Matters
1.    Routine Matters
a.    Election of Directors
(1)
Generally. The Advisor will generally support the election of directors that result in a board made up of a majority of independent directors. In general, the Advisor will vote in favor of management’s director nominees if they are running unopposed. The Advisor believes that management is in the best possible position to evaluate the qualifications of directors and the needs and dynamics of a particular board. The Advisor of course maintains the ability to vote against any candidate whom it feels is not qualified or if there are specific concerns about the individual, such as allegations of criminal wrongdoing or breach of fiduciary responsibilities. Additional information the Advisor may consider concerning director nominees include, but is not limited to, whether (1) there is an adequate explanation for repeated absences at board meetings, (2) the nominee receives non-board fee compensation, or (3) there is a family relationship between the nominee and the company’s chief executive officer or controlling shareholder. When management’s nominees are opposed in a proxy contest, the Advisor will evaluate which nominees’ publicly-announced management policies and goals are most likely to maximize shareholder value, as well as the past performance of the incumbents.
(2)
Committee Service. The Advisor will withhold votes for non-independent directors who serve on the audit, compensation, and/or nominating committees of the board.
(3)
Classification of Boards. The Advisor will support proposals that seek to declassify boards. Conversely, the Advisor will oppose efforts to adopt classified board structures.
(4)
Majority Independent Board. The Advisor will support proposals calling for a majority of independent directors on a board. The Advisor believes that a majority of independent directors can help to facilitate objective decision making and enhances accountability to shareholders.
(5)
Majority Vote Standard for Director Elections. The Advisor will vote in favor of proposals calling for directors to be elected by an affirmative majority of the votes cast in a board election, provided that the proposal allows for a plurality voting standard in the case of contested elections. The Advisor may consider voting against such shareholder proposals where a company’s board has adopted an alternative measure, such as a director resignation policy, that provides a meaningful alternative to the majority voting standard and appropriately addresses situations where an incumbent director fails to receive the support of the majority of the votes cast in an uncontested election.
(6)
Withholding Campaigns. The Advisor will support proposals calling for shareholders to withhold votes for directors where such actions will advance the principles set forth in paragraphs (1) through (5) above.
b.    Ratification of Selection of Auditors
The Advisor will generally rely on the judgment of the issuer’s audit committee in selecting the independent auditors who will provide the best service to the company. The Advisor believes that independence of the auditors is paramount and will vote against auditors whose independence appears to be impaired. The Advisor will vote against proposed auditors in those circumstances where (1) an auditor has a financial interest in or association with the company, and is therefore not independent; (2) non-audit fees comprise more than 50% of the total fees paid by the company to the audit firm; or (3)

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there is reason to believe that the independent auditor has previously rendered an opinion to the issuer that is either inaccurate or not indicative of the company’s financial position.
2.    Compensation Matters
a.    Executive Compensation
(1)
Advisory Vote on Compensation. The Advisor believes there are more effective ways to convey concerns about compensation than through an advisory vote on compensation (such as voting against specific excessive incentive plans or withholding votes from compensation committee members). The Advisor will consider and vote on a case-by-case basis on say-on-pay proposals and will generally support management proposals unless specific concerns exist, including if the Advisor concludes that executive compensation is (i) misaligned with shareholder interests, (ii) unreasonable in amount, or (iii) not in the aggregate meaningfully tied to the company’s performance.
(2)
Frequency of Advisory Votes on Compensation. The Advisor generally supports the triennial option for the frequency of say-on-pay proposals, but will consider management recommendations for an alternative approach.
b.    Equity Based Compensation Plans
The Advisor believes that equity-based incentive plans are economically significant issues upon which shareholders are entitled to vote. The Advisor recognizes that equity-based compensation plans can be useful in attracting and maintaining desirable employees. The cost associated with such plans must be measured if plans are to be used appropriately to maximize shareholder value. The Advisor will conduct a case-by-case analysis of each stock option, stock bonus or similar plan or amendment, and generally approve management’s recommendations with respect to adoption of or amendments to a company’s equity-based compensation plans, provided that the total number of shares reserved under all of a company’s plans is reasonable and not excessively dilutive.
The Advisor will review equity-based compensation plans or amendments thereto on a case-by-case basis. Factors that will be considered in the determination include the company’s overall capitalization, the performance of the company relative to its peers, and the maturity of the company and its industry; for example, technology companies often use options broadly throughout its employee base which may justify somewhat greater dilution.
Amendments which are proposed in order to bring a company’s plan within applicable legal requirements will be reviewed by the Advisor’s legal counsel; amendments to executive bonus plans to comply with IRS Section 162(m) disclosure requirements, for example, are generally approved.
The Advisor will generally vote against the adoption of plans or plan amendments that:
Provide for immediate vesting of all stock options in the event of a change of control of the company without reasonable safeguards against abuse (see “Anti-Takeover Proposals” below);
Reset outstanding stock options at a lower strike price unless accompanied by a corresponding and proportionate reduction in the number of shares designated. The Advisor will generally oppose adoption of stock option plans that explicitly or historically permit repricing of stock options, regardless of the number of shares reserved for issuance, since their effect is impossible to evaluate;
Establish restriction periods shorter than three years for restricted stock grants;
Do not reasonably associate awards to performance of the company; or
Are excessively dilutive to the company.
3.    Anti-Takeover Proposals
In general, the Advisor will vote against any proposal, whether made by management or shareholders, which the Advisor believes would materially discourage a potential acquisition or takeover. In most cases an acquisition or takeover of a particular company will increase share value. The adoption of anti-takeover measures may prevent or frustrate a bid from being made, may prevent consummation of the acquisition, and may have a negative effect on share price when no acquisition proposal is pending. The items below discuss specific anti-takeover proposals.
a.    Cumulative Voting
The Advisor will vote in favor of any proposal to adopt cumulative voting and will vote against any proposal to eliminate cumulative voting that is already in place, except in cases where a company has a staggered board. Cumulative voting gives minority shareholders a stronger voice in the company and a greater chance for representation on the board. The Advisor believes that the elimination of cumulative voting constitutes an anti-takeover measure.

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b.    Staggered Board
If a company has a “staggered board,” its directors are elected for terms of more than one year and only a segment of the board stands for election in any year. Therefore, a potential acquiror cannot replace the entire board in one year even if it controls a majority of the votes. Although staggered boards may provide some degree of continuity and stability of leadership and direction to the board of directors, the Advisor believes that staggered boards are primarily an anti-takeover device and will vote against establishing them and for eliminating them. However, the Advisor does not necessarily vote against the re-election of directors serving on staggered boards.
c.    “Blank Check” Preferred Stock
Blank check preferred stock gives the board of directors the ability to issue preferred stock, without further shareholder approval, with such rights, preferences, privileges and restrictions as may be set by the board. In response to a hostile takeover attempt, the board could issue such stock to a friendly party or “white knight” or could establish conversion or other rights in the preferred stock which would dilute the common stock and make an acquisition impossible or less attractive. The argument in favor of blank check preferred stock is that it gives the board flexibility in pursuing financing, acquisitions or other proper corporate purposes without incurring the time or expense of a shareholder vote. Generally, the Advisor will vote against blank check preferred stock. However, the Advisor may vote in favor of blank check preferred if the proxy statement discloses that such stock is limited to use for a specific, proper corporate objective as a financing instrument.
d.    Elimination of Preemptive Rights
When a company grants preemptive rights, existing shareholders are given an opportunity to maintain their proportional ownership when new shares are issued. A proposal to eliminate preemptive rights is a request from management to revoke that right.
While preemptive rights will protect the shareholder from having its equity diluted, it may also decrease a company’s ability to raise capital through stock offerings or use stock for acquisitions or other proper corporate purposes. Preemptive rights may therefore result in a lower market value for the company’s stock. In the long term, shareholders could be adversely affected by preemptive rights. The Advisor generally votes against proposals to grant preemptive rights, and for proposals to eliminate preemptive rights.
e.    Non-targeted Share Repurchase
A non-targeted share repurchase is generally used by company management to prevent the value of stock held by existing shareholders from deteriorating. A non-targeted share repurchase may reflect management’s belief in the favorable business prospects of the company. The Advisor finds no disadvantageous effects of a non-targeted share repurchase and will generally vote for the approval of a non-targeted share repurchase subject to analysis of the company’s financial condition.
f.    Increase in Authorized Common Stock
The issuance of new common stock can also be viewed as an anti-takeover measure, although its effect on shareholder value would appear to be less significant than the adoption of blank check preferred. The Advisor will evaluate the amount of the proposed increase and the purpose or purposes for which the increase is sought. If the increase is not excessive and is sought for proper corporate purposes, the increase will be approved. Proper corporate purposes might include, for example, the creation of additional stock to accommodate a stock split or stock dividend, additional stock required for a proposed acquisition, or additional stock required to be reserved upon exercise of employee stock option plans or employee stock purchase plans. Generally, the Advisor will vote in favor of an increase in authorized common stock of up to 100%; increases in excess of 100% are evaluated on a case-by-case basis, and will be voted affirmatively if management has provided sound justification for the increase.
g.    “Supermajority” Voting Provisions or Super Voting Share Classes
A “supermajority” voting provision is a provision placed in a company’s charter documents which would require a “supermajority” (ranging from 66 to 90%) of shareholders and shareholder votes to approve any type of acquisition of the company. A super voting share class grants one class of shareholders a greater per-share vote than those of shareholders of other voting classes. The Advisor believes that these are standard anti-takeover measures and will generally vote against them. The supermajority provision makes an acquisition more time-consuming and expensive for the acquiror. A super voting share class favors one group of shareholders disproportionately to economic interest. Both are often proposed in conjunction with other anti-takeover measures.
h.    “Fair Price” Amendments
This is another type of charter amendment that would require an offeror to pay a “fair” and uniform price to all shareholders in an acquisition. In general, fair price amendments are designed to protect shareholders from coercive, two-

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tier tender offers in which some shareholders may be merged out on disadvantageous terms. Fair price amendments also have an anti-takeover impact, although their adoption is generally believed to have less of a negative effect on stock price than other anti-takeover measures. The Advisor will carefully examine all fair price proposals. In general, the Advisor will vote against fair price proposals unless the Advisor concludes that it is likely that the share price will not be negatively affected and the proposal will not have the effect of discouraging acquisition proposals.
i.    Limiting the Right to Call Special Shareholder Meetings.
The corporation statutes of many states allow minority shareholders at a certain threshold level of ownership (frequently 10%) to call a special meeting of shareholders. This right can be eliminated (or the threshold increased) by amendment to the company’s charter documents. The Advisor believes that the right to call a special shareholder meeting is significant for minority shareholders; the elimination of such right will be viewed as an anti-takeover measure and the Advisor will generally vote against proposals attempting to eliminate this right and for proposals attempting to restore it.
j.    Poison Pills or Shareholder Rights Plans
Many companies have now adopted some version of a poison pill plan (also known as a shareholder rights plan). Poison pill plans generally provide for the issuance of additional equity securities or rights to purchase equity securities upon the occurrence of certain hostile events, such as the acquisition of a large block of stock.
The basic argument against poison pills is that they depress share value, discourage offers for the company and serve to “entrench” management. The basic argument in favor of poison pills is that they give management more time and leverage to deal with a takeover bid and, as a result, shareholders may receive a better price. The Advisor believes that the potential benefits of a poison pill plan are outweighed by the potential detriments. The Advisor will generally vote against all forms of poison pills.
The Advisor will, however, consider on a case-by-case basis poison pills that are very limited in time and preclusive effect. The Advisor will generally vote in favor of such a poison pill if it is linked to a business strategy that will - in our view - likely result in greater value for shareholders, if the term is less than three years, and if shareholder approval is required to reinstate the expired plan or adopt a new plan at the end of this term.
k.    Golden Parachutes
Golden parachute arrangements provide substantial compensation to executives who are terminated as a result of a takeover or change in control of their company. The existence of such plans in reasonable amounts probably has only a slight anti-takeover effect. In voting, the Advisor will evaluate the specifics of the plan presented.
l.    Reincorporation
Reincorporation in a new state is often proposed as one part of a package of anti-takeover measures. Several states (such as Pennsylvania, Ohio and Indiana) now provide some type of legislation that greatly discourages takeovers. Management believes that Delaware in particular is beneficial as a corporate domicile because of the well-developed body of statutes and case law dealing with corporate acquisitions.
The Advisor will examine reincorporation proposals on a case-by-case basis. Generally, if the Advisor believes that the reincorporation will result in greater protection from takeovers, the reincorporation proposal will be opposed. The Advisor will also oppose reincorporation proposals involving jurisdictions that specify that directors can recognize non-shareholder interests over those of shareholders. When reincorporation is proposed for a legitimate business purpose and without the negative effects identified above, the Advisor will generally vote affirmatively.
m.    Confidential Voting
Companies that have not previously adopted a “confidential voting” policy allow management to view the results of shareholder votes. This gives management the opportunity to contact those shareholders voting against management in an effort to change their votes.
Proponents of secret ballots argue that confidential voting enables shareholders to vote on all issues on the basis of merit without pressure from management to influence their decision. Opponents argue that confidential voting is more expensive and unnecessary; also, holding shares in a nominee name maintains shareholders’ confidentiality. The Advisor believes that the only way to insure anonymity of votes is through confidential voting, and that the benefits of confidential voting outweigh the incremental additional cost of administering a confidential voting system. Therefore, the Advisor will generally vote in favor of any proposal to adopt confidential voting.
n.    Opting In or Out of State Takeover Laws
State takeover laws typically are designed to make it more difficult to acquire a corporation organized in that state. The Advisor believes that the decision of whether or not to accept or reject offers of merger or acquisition should be made by

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the shareholders, without unreasonably restrictive state laws that may impose ownership thresholds or waiting periods on potential acquirors. Therefore, the Advisor will generally vote in favor of opting out of restrictive state takeover laws.
4.    Transaction Related Proposals
The Advisor will review transaction related proposals, such as mergers, acquisitions, and corporate reorganizations, on a case-by-case basis, taking into consideration the impact of the transaction on each client account. In some instances, such as the approval of a proposed merger, a transaction may have a differential impact on client accounts depending on the securities held in each account. For example, whether a merger is in the best interest of a client account may be influenced by whether an account holds, and in what proportion, the stock of both the acquirer and the acquiror. In these circumstances, the Advisor may determine that it is in the best interests of the accounts to vote the accounts’ shares differently on proposals related to the same transaction.
5.    Other Matters
a.    Shareholder Proposals Involving Social, Moral or Ethical Matters
The Advisor will generally vote in accordance with management’s recommendation on issues that primarily involve social, moral or ethical matters, such as the MacBride Principles pertaining to operations in Northern Ireland. While the resolution of such issues may have an effect on shareholder value, the precise economic effect of such proposals, and individual shareholder’s preferences regarding such issues, is often unclear. Where this is the case, the Advisor believes it is generally impossible to know how to vote in a manner that would accurately reflect the views of the Advisor’s clients, and therefore will review management’s assessment of the economic effect of such proposals and rely upon it if the Advisor believes its assessment is not unreasonable.
Shareholders may also introduce social, moral or ethical proposals which are the subject of existing law or regulation. Examples of such proposals would include a proposal to require disclosure of a company’s contributions to political action committees or a proposal to require a company to adopt a non-smoking workplace policy. The Advisor believes that such proposals are better addressed outside the corporate arena, and will generally vote with management’s recommendation; in addition, the Advisor will generally vote against any proposal which would require a company to adopt practices or procedures which go beyond the requirements of existing, directly applicable law.
b.    Anti-Greenmail Proposals
“Anti-greenmail” proposals generally limit the right of a corporation, without a shareholder vote, to pay a premium or buy out a 5% or greater shareholder. Management often argues that they should not be restricted from negotiating a deal to buy out a significant shareholder at a premium if they believe it is in the best interest of the company. Institutional shareholders generally believe that all shareholders should be able to vote on such a significant use of corporate assets. The Advisor believes that any repurchase by the company at a premium price of a large block of stock should be subject to a shareholder vote. Accordingly, it will generally vote in favor of anti-greenmail proposals.
c.    Indemnification
The Advisor will generally vote in favor of a corporation’s proposal to indemnify its officers and directors in accordance with applicable state law. Indemnification arrangements are often necessary in order to attract and retain qualified directors. The adoption of such proposals appears to have little effect on share value.
d.    Non-Stock Incentive Plans
Management may propose a variety of cash-based incentive or bonus plans to stimulate employee performance. In general, the cash or other corporate assets required for most incentive plans is not material, and the Advisor will vote in favor of such proposals, particularly when the proposal is recommended in order to comply with IRC Section 162(m) regarding salary disclosure requirements. Case-by-case determinations will be made of the appropriateness of the amount of shareholder value transferred by proposed plans.
e.    Director Tenure
These proposals ask that age and term restrictions be placed on the board of directors. The Advisor believes that these types of blanket restrictions are not necessarily in the best interests of shareholders and therefore will vote against such proposals, unless they have been recommended by management.
f.    Directors’ Stock Options Plans
The Advisor believes that stock options are an appropriate form of compensation for directors, and the Advisor will generally vote for director stock option plans which are reasonable and do not result in excessive shareholder dilution. Analysis of such proposals will be made on a case-by-case basis, and will take into account total board compensation and the company’s total exposure to stock option plan dilution.

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g.    Director Share Ownership
The Advisor will generally vote against shareholder proposals which would require directors to hold a minimum number of the company’s shares to serve on the Board of Directors, in the belief that such ownership should be at the discretion of Board members.
h.    Non-U.S. Proxies
The Advisor will generally evaluate non-U.S. proxies in the context of the voting policies expressed herein but will also, where feasible, take into consideration differing laws, regulations, and practices in the relevant foreign market in determining if and how to vote. There may also be circumstances when practicalities and costs involved with non-U.S. investing make it disadvantageous to vote shares. For instance, the Advisor generally does not vote proxies in circumstances where share blocking restrictions apply, when meeting attendance is required in person, or when current share ownership disclosure is required.
C.
Use of Proxy Advisory Services
The Advisor takes into account information from many different sources, including independent proxy advisory services. However, the decision on how to vote proxies will be made by the Advisor in accordance with these policies and will not be delegated to a proxy advisory service.
D.
Monitoring Potential Conflicts of Interest
Corporate management has a strong interest in the outcome of proposals submitted to shareholders. As a consequence, management often seeks to influence large shareholders to vote with their recommendations on particularly controversial matters. In the vast majority of cases, these communications with large shareholders amount to little more than advocacy for management’s positions and give the Advisor’s staff the opportunity to ask additional questions about the matter being presented. Companies with which the Advisor has direct business relationships could theoretically use these relationships to attempt to unduly influence the manner in which the Advisor votes on matters for its clients. To ensure that such a conflict of interest does not affect proxy votes cast for the Advisor’s clients, our proxy voting personnel regularly catalog companies with whom the Advisor has significant business relationships; all discretionary (including case-by-case) voting for these companies will be voted by the client or an appropriate fiduciary responsible for the client (e.g., a committee of the independent directors of a fund or the trustee of a retirement plan).
In addition, to avoid any potential conflict of interest that may arise when one American Century fund owns shares of another American Century fund, the Advisor will “echo vote” such shares, if possible. Echo voting means the Advisor will vote the shares in the same proportion as the vote of all of the other holders of the fund’s shares. So, for example, if shareholders of a fund cast 80% of their votes in favor of a proposal and 20% against the proposal, any American Century fund that owns shares of such fund will cast 80% of its shares in favor of the proposal and 20% against. When this is not possible (as in the case of the “NT” funds, where the One Choice Target Date funds are the sole shareholder), the shares of the underlying fund (e.g. the “NT” fund) will be voted in the same proportion as the vote of the shareholders of the corresponding American Century policy portfolio for proposals common to both funds. For example, NT Growth Fund shares will be echo voted in accordance with the votes of the Growth Fund shareholders. In the case where the policy portfolio does not have a common proposal, shares will be voted in consultation with a committee of the independent directors.
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The voting policies expressed above are of course subject to modification in certain circumstances and will be reexamined from time to time. With respect to matters that do not fit in the categories stated above, the Advisor will exercise its best judgment as a fiduciary to vote in the manner which will most enhance shareholder value.
Case-by-case determinations will be made by the Advisor’s staff, which is overseen by the General Counsel of the Advisor, in consultation with equity managers. Electronic records will be kept of all votes made.



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Notes



























American Century Investments
americancenturyetfs.com
P.O. Box 419786
Kansas City, Missouri 64141-6786
1-833-ACI-ETFS



Investment Company Act File No. 811-23305
CL-SAI-93576        







AMERICAN CENTURY ETF TRUST

PART C OTHER INFORMATION

Item 28. Exhibits
(a)
(1)    Certificate of Trust, dated June 27, 2017 (filed electronically as Exhibit a1 to Pre-Effective Amendment No. 1 to the Registration Statement of the Registrant on December 20, 2017, File No. 333-221045, and incorporated herein by reference).
(2)    Amended and Restated Agreement and Declaration of Trust, dated November 10, 2017 (filed electronically as Exhibit a2 to Pre-Effective Amendment No. 1 to the Registration Statement of the Registrant on December 20, 2017, File No. 333-221045, and incorporated herein by reference).
(b)
Amended and Restated Bylaws, dated November 10, 2017 (filed electronically as Exhibit b to Pre-Effective Amendment No. 1 to the Registration Statement of the Registrant on December 20, 2017, File No. 333-221045, and incorporated herein by reference).
(c)
Registrant hereby incorporates by reference, as though set forth fully herein, Article III, Article IV, Article V, Article VI and Article VIII of Registrant’s Amended and Restated Agreement and Declaration of Trust, appearing as Exhibit (a) herein and Article II, Article VI, and Article VII of Registrant’s Amended and Restated Bylaws, appearing as Exhibit (b) herein.
(d)
Management Agreement between American Century ETF Trust and American Century Investment Management, Inc., effective as of January 8, 2018, is included herein.
(e)
(1)    ETF Distribution Agreement between American Century ETF Trust and Foreside Fund Services, LLC, dated December 13, 2017, is included herein.
(2)    Form of Authorized Participant Agreement, is included herein.
(f)        Not applicable.
(g)
(1)    Master Custodian Agreement with State Street Bank and Trust Company, made as of July 29, 2011 (filed electronically as Exhibit g2 to Post-Effective Amendment No. 61 to the Registration Statement of American Century Government Income Trust on July 29, 2011, File No. 2-99222, and incorporated herein by reference).
(2)
Amendment to Master Custodian Agreement with State Street Bank and Trust Company, made as of May 21, 2015 (filed electronically as Exhibit g3 to Post-Effective Amendment No. 57 to the Registration Statement of American Century Target Maturities Trust on January 28, 2016, File No. 002-94608, and incorporated herein by reference).
(3)
Amendment to Master Custodian Agreement with State Street Bank and Trust Company, dated January 9, 2018, is included herein.
(h)
(1)        Transfer Agency Agreement between State Street Bank and Trust Company and American Century Investment Management, Inc., dated January 9, 2018, is included herein.
(2)    Form of Participation Agreement is included herein.
(i)
Opinion and Consent of Counsel, dated January 8, 2018, is included herein.
(j)
Consent of Deloitte & Touche LLP, independent registered public accounting firm, is included herein.
(k)            Not applicable.
(l)             Initial Capital Agreement, dated December 21, 2017, is included herein.
(m)
Master Distribution and Individual Shareholder Services Plan of American Century ETF Trust, dated January 9, 2018, is included herein.
(n)        Not applicable.
(o)        Not applicable.
(p)
(1)    American Century Investments Code of Ethics (filed electronically as Exhibit p1 to Post-Effective Amendment No. 59 to the Registration Statement of American Century California Tax-Free and Municipal Funds on December 29, 2016, File No. 2-82734, and incorporated herein by reference).
(2)    Independent Directors’ Code of Ethics, is included herein.




(q)
(1)    Power of Attorney, dated November 13, 2017 (filed electronically as Exhibit q1 to Pre-Effective Amendment No. 1 to the Registration Statement of the Registrant on December 20, 2017, File No. 333-221045, and incorporated herein by reference).
 
(2)    Secretary’s Certificate, dated November 13, 2017 (filed electronically as Exhibit q2 to Pre-Effective Amendment No. 1 to the Registration Statement of the Registrant on December 20, 2017, File No. 333-221045, and incorporated herein by reference).

Item 29.     Persons Controlled by or Under Common Control with Registrant.
Certain trustees of the Registrant serve, in substantially identical capacities, other registered investment companies in the American Century family of funds. In addition, certain officers of the Registrant serve as officers for other registered investment companies in the American Century family of funds, each of which has American Century Investment Management, Inc. as its investment advisor. Nonetheless, the Registrant takes the position that it is not under common control with other American Century investment companies because the power residing in the respective boards and officers arises as a result of an official position with the respective investment companies.
Item 30. Indemnification
The Registrant incorporates by reference, as though set forth fully herein, Section 7.5 and Section 7.6 of the Registrant’s Amended and Restated Declaration of Trust appearing as Exhibit (a)(2) herein.
The Registrant has purchased an insurance policy insuring its officers and directors against certain liabilities which such officers and directors may incur while acting in such capacities and providing reimbursement to the Registrant for sums which it may be permitted or required to pay to its officers and directors by way of indemnification against such liabilities, subject in either case to clauses respecting deductibility and participation.

Item 31. Business and Other Connections of Investment Advisor
In addition to serving as the Registrant’s investment advisor, American Century Investment Management, Inc. (ACIM) provides portfolio management services for other investment companies as well as for other business and institutional clients. Business backgrounds of the directors and principal executive officers of the advisor that also hold positions with the Registrant are included under “Management” in the Statement of Additional Information included in this registration statement. The remaining principal executive officers and directors of the advisor and their principal occupations during the past 2 fiscal years are as follows:

Jim Shore (Vice President of ACIM). Served as Founding Principal and Portfolio Manager, NorthRoad Capital Management, 530 5th Avenue, Lobby 1, New York, NY 10036, 2002 to 2017.
Al Polit (Vice President of ACIM). Served as Partner and Senior Portfolio Manager, Lombardia Capital Partners, LLC, 55 South Lake Avenue, Suite 750, Pasadena, CA 91101, 2011 to 2017.
Edward Rosenberg (Senior Vice President of ACIM). Served as Senior Vice President, Flexshares Head of ETF Capital Markets, Northern Trust, 50 South La Salle Street, Chicago, IL 60690, 2012 to 2017.
Elaine Bourke (Vice President of ACIM). Served as Product Specialist, Credit Suisse Asset Management, 11 Madison Avenue, New York, NY 10010, 2011 to 2017.
Guillaume Mascotto (Vice President of ACIM) Served as Vice President, Pacific Investment Management Company, 650 Newport Center Drive, Newport Beach, CA 92660, 2017 and Senior ESG Research Analyst, MSCI Inc., 250 Greenwich Street, New York, NY 10007, 2014 to 2017.
Matt Lewis (Vice President of ACIM). Served as Head, iShares Broker Dealer Execution Services-America, BlackRock, 400 Howard Street, San Francisco, CA 94105,