Compare Investments_SPHD vs SCHD While investors have focused on high-flying Magnificent 7 stocks, Warren Buffett’s Berkshire Hathaway has quietly outperformed the SPDR S&P 500 ETF Trust (SPY), the stock market proxy and largest exchange-traded fund on the market. As a conglomerate that owns shares of 41 publicly traded companies, Berkshire possesses multiple ETF qualities.