Warren Buffett is one of the most widely followed investment managers in the world. And there's good reason for that. His track record of market-beating returns dates back to the 1950s when he founded Buffett Limited Partners.

Warren Buffett’s Berkshire Hathaway (BRK.A) (BRK.B) has recently increased its stake in Sirius XM Holdings Inc. (SIRI), now owning over 35% of

Warren Buffett’s Berkshire Hathaway has spent another $54 million to purchase Sirius XM stock, giving it a stake of more than 35% in the satellite-radio company.