ProShares UltraShort S&P500 (the Fund) seeks daily investment results that correspond to twice (200%) the inverse (opposite) of the daily performance of the S&P 500 (the Index). The Index is a measure of large-cap the United States stock market performance. It is a float-adjusted, market capitalization-weighted index of 500 United States operating companies and real estate investment trusts selected through a process that factors criteria, such as liquidity, price, market capitalization and financial viability. The Fund invests in common stock issued by public companies. The Fund invests in derivatives, which are financial instruments whose value is derived from the value of an underlying asset, interest rate or index. The Fund is advised by ProShare Advisors LLC.