Warren Buffett's stock pickers are crushing it

So far, so good for the stock pickers Warren Buffett plucked from relative obscurity to manage billions of his dollars.

Ted Weschler and Todd Combs run more than $14 billion for Berkshire Hathaway (BRK-A) and could manage much more as part of Buffett's succession plan. An analysis by Fortune estimates that they have more than accomplished their simple but often difficult mandate to beat the S&P 500 (^GSPC), the benchmark their pay is tied to over a three year period.

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Combs has generated a cumulative return of 116 percent over the past nearly four years, more than double the index's 55 percent gain over the same period, according to Fortune's estimates.

Combs picks increased 51 percent last year alone. Weschler's portfolio is up 81 percent in three years and is well ahead of the market this year.

Combs and Weschler declined to comment to Fortune. Buffett told the magazine just that Weschler's performance exceeds its estimates.

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