The SPDR S&P 500 ETF trust is an exchange-traded fund which trades on the NYSE Arca under the symbol SPY. SPDR is an acronym for the Standard & Poor's Depositary Receipts, the former name of the ETF. It is designed to track the S&P 500 stock market index. This fund is the largest and oldest ETF in the USA. SPDR is a trademark of Standard and Poor's Financial Services LLC, a subsidiary of S&P Global. The ETF's CUSIP is 78462F103 and its ISIN is US78462F1030. The trustee of the SPDR S&P 500 ETF Trust is State Street Bank and Trust Company. The fund has a net expense ratio of 0.0945%. Wikipedia