Strategy. 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 … Show more… 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 leverages 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 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, 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 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 returns consistent with the Funds investment objective. The Fund may invest in or gain 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 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 exposure to the returns of the Index without regard to market conditions, trends or direction. The Fund will concentrate (i.e., invest in securities that represent 25 percent or more of the value of the Index) or focus (i.e., invest in securities that represent a substantial portion of its value, but less than 25 percent) its investments in a particular industry or group of industries to approximately the same extent the Index is so concentrated or focused. As of May 31, 2021, the Index was not concentrated in an industry group, but was focused in the information technology and financials industry groups. Please see Investment Objectives, Principal Investment Strategies and Related Risks in the Funds Prospectus for additional details. Show less