Warren Buffett's 10 biggest holdings
Wells Fargo & Company
Berkshire owns 456,170,061 shares in Wells Fargo, which comes out to an 8.7% ownership stake.
Note:Yet another member of Berkshire's "Big Four," Buffett and Co. increased their ownership to 8.7% from 7.6% at the end of 2011. He quotes Mae West, who said: "Too much of a good thing can be wonderful."
Source: Berkshire Hathaway annual shareholder letter