SPDR S&P 500 ETF Trust is a company in the U.S. stock market and it is a holding in 7 U.S.-traded ETFs. SPY has around 354.6K shares in the U.S. ETF market. The largest ETF holder of SPY is the SPDR SSgA Global Allocation ETF (GAL), with approximately 151.96K shares. Investors may also find of interest that the ETF with the largest allocation to SPY stock is Hull Tactical U.S. ETF (HTUS), with a portfolio weight of 73.50%. On average, U.S. ETFs allocate 30.88% of SPY to their portfolios.