American Century Short Duration Inflation Protection Bond Fund Investor Class (APOIX) is an open-end fixed income mutual fund that seeks total return through a strategy designed to protect against U.S. inflation by normally investing at least 80% of its net assets in inflation-linked debt securities, primarily investment-grade securities with a weighted average duration of five years or shorter; these include inflation-linked U.S. Treasury securities (TIPS), inflation-linked securities issued by U.S. government agencies and instrumentalities other than the Treasury, and inflation-linked securities from domestic and foreign corporations and governments. The fund also allocates a portion of assets to high-yield (junk) bonds and fixed-income securities not linked to inflation; it may invest up to 20% in foreign currency-denominated securities or U.S. dollar-denominated securities of foreign issuers, with current holdings emphasizing U.S. bonds (93.33%), non-U.S. bonds (5.13%), and cash (1.10%) across 126 positions, where the top ten holdings comprise 61.19% of the $1.51 billion in net assets. Managed by American Century Investment Management Inc., a subsidiary of American Century Investments--founded in 1958 and headquartered in Kansas City, Missouri, with additional offices in New York, London, Hong Kong, and Sydney--the fund benchmarks performance against the Bloomberg U.S. 1-5 Year Treasury Inflation-Protected Securities (TIPS) Index and is available to U.S. investors through non-retirement accounts (minimum initial investment $2,500), IRAs ($1,000), and other share classes. In recent developments, portfolio manager Steve Bartolini joined the team on September 9, 2024, complementing existing managers Robert Gahagan (since inception), James Platz (since 2007), and Miguel Castillo (since 2014); the fund, launched May 31, 2005 as part of American Century Investment Trust and formerly known as Inflation Protection Bond Fund, adjusted its strategy in the third quarter of 2024 by favoring longer duration positions, out-of-index securitized securities, and anticipating Federal Reserve rate cuts into mid-2025 amid declining TIPS yields. The fund maintains a net expense ratio of 0.61%-0.70%, a turnover ratio of 24%, and serves individual investors, financial advisors, institutions, and retirement plans focused on inflation-protected short-term bond exposure in the U.S. and select global fixed income markets.