Normally investing at least 80% of assets in securities of mid-capitalization companies included in the Fidelity U.S. Mid Cap Focused IndexSM. The Fidelity U.S. Mid Cap Focused Index SM is designed to reflect the performance of stocks of mid-capitalization U.S. companies. Mid-capitalization stocks are considered to be stocks whose market capitalization is similar to the market capitalization of companies in the Russell Midcap ® Index or the S&P MidCap 400 ® Index. The Fidelity U.S. Mid Cap Focused Index SM was created by Fidelity Product Services LLC (FPS) using a rules-based proprietary index methodology that includes all U.S. stocks meeting certain market capitalization, liquidity and investability requirements. Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives. Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price-to-earnings (P/E) ratio, price-to-book (P/B) ratio, and earnings growth to attempt to replicate the returns of the Fidelity U.S. Mid Cap Focused IndexSM. Lending securities to earn income for the fund.