Key Takeaways Buffett has long been a big proponent of the index funds that Bogle helped bring to the masses.However, his public declaration that Bogle is an American hero may have also been influenced by the fact that one of Bogle's funds just helped Buffett win a $1 million bet.

Apple, in Buffett’s telling, isn’t just another stock—it’s a company he’d love to own outright if he could. It’s surprising, then, that despite being the single most successful investment of his lifetime,

Warren Buffett is occasionally granted the "confidential treatment" tag, which allows him to build up Berkshire Hathaway's stake in one or more securities in secrecy. Buffett's newly revealed mystery stock -- a $1.