ProShares RAFI Long/Short (RALS) Exchange: NYSE ARCA

The Fund invests in financial instruments that ProShare Advisors believes, in combination, should track the performance of the Index. The Index is constructed and maintained by FTSE International Limited. ).The Index allocates an aggregate equal dollar amount to both long and short equity positions each time that the Index rebalances. This allocation is based on a comparison of Research Affiliates Fundamental Index® weightings with traditional market capitalization weightings. To be “long” means to hold or have long exposure to an asset with the expectation that its value will increase over time. To be “short” means to sell or have short exposure to an asset with the expectation that it will fall in value. The long position of the Index consists of the equity securities in the FTSE RAFI US 1000 Total Return Index (the “Long Index”), and the short position of the Index consists of the securities included in the Russell 1000 Total Return Index (the “Short Index”). The Long Index is a “fundamental” index which uses non-price measures of company size (such as sales, dividends, cash flow or book value) to select and weight the securities in the Long Index. The Short Index is a capitalization weighted index. Capitalization-weighted indexes weight securities based on the price of the securities in the index and not fundamental factors. The Index seeks to capitalize on a theory that index weighting based on market capitalization (i.e., price) results in overweighting of overpriced securities and underweighting of underpriced securities. By obtaining long exposure to a non-capitalization weighted “fundamental” index and short exposure to a market capitalization weighted index in an equal dollar amount, the Index seeks to deliver the difference in performance (outperformance or underperformance) between the fundamentally weighted index and the market capitalization weighted index. In general, when fundamental weighting is outperforming capitalization weighting, the Index, expects to have positive performance. When capitalization weighting is outperforming fundamental weighting, the Index and Fund expect to have negative performance. The Fund may be an appropriate investment for investors who believe that, over time, fundamental indexes tend to have better performance than capitalization-weighted indexes. The Index is published under the Bloomberg ticker symbol “FR10LSTR”. 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. Equity Securities — The Fund invests in common stock issued by public companies. 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 or funds (including exchange-traded funds (“ETFs”)), interest rates or indexes. The Fund invests in derivatives as a substitute for investing directly in or taking short positions in the equity securities comprising the Index. 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.ProShare Advisors follows a passive approach to investing that is designed to track the performance of the Index. The Fund attempts to track the performance of the Index by investing all, or substantially all, of its assets in investments that make up the Index or in financial instruments that provide similar exposure. The Fund may invest in or gain exposure to only a representative sample of the securities in the Index, to securities not contained in the Index or to other financial instruments, with the intent of obtaining exposure with aggregate characteristics similar to those 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 or instrument, 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 exposure to the Index without regard to market conditions, trends or direction. 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, 2018, the Index’s short exposure was concentrated in the information technology industry group. Please see “Investment Objectives, Principal Investment Strategies and Related Risks” in the Fund’s Full Prospectus for additional details.