In fact, it's possible that Buffett will eventually buy the entire business outright. Buffett's mystery stock is none other than insurer Chubb (NYSE: CB). We won't ever know the full details behind the disclosure exemption,

Warren Buffett is known as a value investor. But he has also identified some of the best growth stocks of the past century. Right now, his holding company, Berkshire Hathaway, has more than $1 billion invested in what I believe could be the top-performing stock in his portfolio during the next decade.

Warren Buffett is the undisputed greatest investor of all time, and his success at Berkshire Hathaway (NYSE: BRK.A) (NYSE: BRK.B), the conglomerate he has run for almost 60 years, has made thousands of investors rich alongside him.

Every May, tens of thousands of investors descend upon Omaha, Nebraska, for the annual meeting of Warren Buffett's company, Berkshire Hathaway ( BRK.A) ( BRK.B -0.36%). Clearly, lots of people are very interested not only in the impressive company,