Fortune 500 rank: 11
2009 profit: $8.1 billion
Warren Buffett's portfolio roared back in 2009. As stock markets soared, earnings jumped by more than half at Berkshire Hathaway. The net value of his company's stock holdings doubled during the year as its stakes in Coca-Cola, Wells Fargo, and American Express rose.
Berkshire's derivatives tied to stock indexes added another $1 billion in earnings in the fourth quarter alone -- the year before, they lost $4.6 billion.
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