ProShares UltraShort MidCap400 (MZZ) Exchange: NYSE ARCA

The Fund invests in financial instruments that ProShare Advisors believes, in combination, should produce daily returns consistent with the Fund’s investment objective. The Index is constructed and maintained by S&P Dow Jones Indices LLC. The Index is a measure of mid-size company U.S. stock market performance. It is a float-adjusted, market capitalization-weighted index of 400 U.S. operating companies and real estate investment trusts selected through a process that factors in criteria such as liquidity, price, market capitalization and financial viability. The Index is published under the Bloomberg ticker symbol “MID.” The Fund will invest principally in the financial instruments set forth below. The Fund expects that its cash balances maintained in connection with the use of financial instruments will typically be held in money market instruments. Derivatives — The Fund invests in derivatives, which are financial instruments whose value is derived from the value of an underlying asset or assets, such as stocks, bonds, funds (including exchange-traded funds (“ETFs”)), interest rates or indexes. The Fund invests in derivatives as a substitute for directly shorting stocks in order to seek returns for a single day that are inverse leveraged (-2x) to the returns of the Index for that day. These derivatives principally include: Swap Agreements — Contracts entered into primarily with major global financial institutions for a specified period ranging from a day to more than one year. In a standard “swap” transaction, two parties agree to exchange the return (or differentials in rates of return) earned or realized on particular predetermined investments or instruments. The gross return to be exchanged or “swapped” between the parties is calculated with respect to a “notional amount,” e.g., the return on or change in value of a particular dollar amount invested in a “basket” of securities or an ETF representing a particular index.Futures Contracts — Standardized contracts traded on, or subject to the rules of, an exchange that call for the future delivery of a specified quantity and type of asset at a specified time and place or, alternatively, may call for cash settlement. Money Market Instruments — The Fund invests in short-term cash instruments that have a remaining maturity of 397 days or less and exhibit high quality credit profiles, for example: U.S. Treasury Bills — U.S. government securities that have initial maturities of one year or less, and are supported by the full faith and credit of the U.S. government.Repurchase Agreements — Contracts in which a seller of securities, usually U.S. government securities or other money market instruments, agrees to buy the securities back at a specified time and price. Repurchase agreements are primarily used by the Fund as a short-term investment vehicle for cash positions. ProShare Advisors uses a mathematical approach to investing. Using this approach, ProShare Advisors determines the type, quantity and mix of investment positions that it believes, in combination, the Fund should hold to produce daily returns consistent with the Fund’s investment objective. The Fund may gain inverse exposure to only a representative sample of the securities in the Index or to securities not contained in the Index or in financial instruments, with the intent of obtaining exposure with aggregate characteristics similar to those of a multiple of the inverse of the single day returns of the Index. In managing the assets of the Fund, ProShare Advisors does not invest the assets of the Fund in securities or financial instruments based on ProShare Advisors’ view of the investment merit of a particular security, instrument, or company, nor does it conduct conventional investment research or analysis or forecast market movement or trends. The Fund seeks to remain fully invested at all times in securities and/or financial instruments that, in combination, provide inverse leveraged exposure to the single day returns of the Index, consistent with its investment objective, without regard to market conditions, trends or direction. The Fund seeks investment results for a single day only, measured as the time the Fund calculates its NAV to the next time the Fund calculates its NAV, and not for any other period. The Fund seeks to engage in daily rebalancing to position its portfolio so that its exposure to the Index is consistent with the Fund’s daily investment objective. The time and manner in which the Fund rebalances its portfolio may vary from day to day at the discretion of ProShare Advisors, depending on market conditions and other circumstances. The Index’s movements during the day will affect whether the Fund’s portfolio needs to be rebalanced. For example, if the Index has risen on a given day, net assets of the Fund should fall (assuming there were no Creation Units issued). As a result, the Fund’s inverse exposure will need to be decreased. Conversely, if the Index has fallen on a given day, net assets of the Fund should rise (assuming there were no Creation Unit redemptions). As a result, the Fund’s inverse exposure will need to be increased. Daily rebalancing and the compounding of each day’s return over time means that the return of the Fund for a period longer than a single day will be the result of each day’s returns compounded over the period, which will very likely differ in amount, and possibly even direction, from two times the inverse (-2x) of the return of the Index for the same period. The Fund will lose money if the Index’s performance is flat over time, and the Fund can lose money regardless of the performance of the Index, as a result of daily rebalancing, the Index’s volatility, compounding of each day’s return and other factors. See “Principal Risks” below. The Fund will concentrate its investments in a particular industry or group of industries to approximately the same extent as the Index is so concentrated. As of the close of business on May 31, 2019, the Index was not concentrated in an industry group.Please see “Investment Objectives, Principal Investment Strategies and Related Risks” in the Fund’s Prospectus for additional details.