Warren Buffett is the CEO of the holding company Berkshire Hathaway. The Oracle of Omaha, Neb., is valued at $50 billion. He bought Berkshire Hathaway in 1965, and in 2009, he bought the railway company Burlington Northern Santa Fe. This past year, Mr. Buffett worked with Bill Gates to convince the richest people in the US to pledge half of their money to charity.
Shannon Stapleton / Reuters / File