CEO Warren Buffett recently disclosed that Berkshire Hathaway (NYSE: BRK-A) (NYSE: BRK-B) owned 133 million shares, or about $18.5 billion, worth of Apple (NASDAQ: AAPL) stock. Apple joins other sizable holdings — Wells Fargo & Co and The Coca-Cola Co — as one of Berkshire Hathaway’s top equity investments.