Strategy. The fund invests in securities through an underlying master fund. BlackRock Fund Advisors is the investment adviser of the S&P 500 Index Master Portfolio, the underlying master fund in which the fund invests. The fund seeks its investment objective by investing substantially all of its investable assets in the underlying master fund. The underlying master fund seeks its objective by investing in the stocks comprising the Standard & Poors (S&P) 500 Index 1 . The weightings of stocks in the S&P 500 Index are based on each stocks relative total market capitalization; that is, its market price per share times the number of shares outstanding. The master fund invests approximately the same percentage of its assets in each stock as … Show more… The fund invests in securities through an underlying master fund. BlackRock Fund Advisors is the investment adviser of the S&P 500 Index Master Portfolio, the underlying master fund in which the fund invests. The fund seeks its investment objective by investing substantially all of its investable assets in the underlying master fund. The underlying master fund seeks its objective by investing in the stocks comprising the Standard & Poors (S&P) 500 Index 1 . The weightings of stocks in the S&P 500 Index are based on each stocks relative total market capitalization; that is, its market price per share times the number of shares outstanding. The master fund invests approximately the same percentage of its assets in each stock as the stock represents in the S&P 500 Index. Under normal circumstances, the master fund invests at least 90% of its net assets (plus the amount of borrowings, if any, for investment purposes) in securities comprising the S&P 500 Index. The master fund attempts to achieve, in both rising and falling markets, a correlation of at least 95% between the total return of its net assets before expenses and the total return of the S&P 500 Index. The master funds ability to match the investment performance of the S&P 500 Index may be affected by, among other things, master fund expenses, the amount of cash and cash equivalents held by the master fund, the manner in which the total return 1 Standard & Poors does not sponsor the fund, nor is it affiliated in any way with the fund or the funds advisers. Standard & Poors , S&P , S&P 500 , and Standard & Poors 500 are trademarks of Standard & Poors Financial Services LLC, a division of S&P Global. The fund is not sponsored, endorsed, sold or promoted by Standard & Poors and Standard & Poors makes no representation or warranty, express or implied, regarding the advisability of investing in the fund. of the S&P 500 Index is calculated, the size of the master funds investment portfolio and the timing, frequency and size of cash flows into and out of the master fund. In the future, the fund or the master fund may select another index if it is deemed to be more representative of the performance of publicly traded common stocks in the aggregate. In seeking to replicate or match the performance of the S&P 500 Index, the master fund may use various investment techniques, such as buying and selling futures contracts and options and purchasing indexed securities. The master fund may also lend its portfolio securities. These techniques may increase the master funds volatility and may involve a small investment of cash relative to the magnitude of the risk being taken. The fund and the master fund may invest not more than 10% of its total assets, under normal market conditions, in cash and high-quality money market instruments. These investments are made to provide liquidity and when there is an unexpected or abnormal level of investments in or redemptions from the fund or the master fund. Show less