Warren Edward Buffett, 80 (born August 30, 1930)
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Warren Edward Buffett has headed Berkshire Hathaway for 40 years and is described as one of the most successful investors in U.S. history. Often called "the sage of Omaha," Buffett's annual letter to shareholders is prized for its common sense and investment insights. He has become one of the world's wealthiest people and plans to donate his vast fortune to a number of foundations, including the Gates Foundation established by Microsoft founder Bill Gates, a friend, Berkshire director, and occasional bridge partner.