Buffett Watch

Down $2.5B this week, IBM & Coke add to Buffett's woes

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Warren Buffett's worst bets
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Warren Buffett loses $1 billion on IBM holdings
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Warren Buffett is happy to admit his mistakes when he makes them—just don't remind him how much money he lost in the process.

IBM and Coke represent two of Berkshire Hathaway's three biggest investments, but their operational missteps have already cost him $2.52 billion this week (factoring in Wednesday's early declines).

On Monday, Buffett lost nearly $1 billion on his third-largest investment, IBM, after the company posted disappointing earnings.

On Tuesday, Coca-Cola did the same thing, posting third-quarter revenue that fell short of expectations and warning of currency headwinds.

The losses in IBM and Coke add to a recent rough patch for Buffett, who slashed Berkshire Hathaway's stake in British grocer Tesco earlier this month.

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He has described buying into the stock as a "huge mistake."

And to be sure, it hasn't been all bad news this week—Buffett's favorite bank, Wells Fargo, is up more than $816 million since Monday morning.