Buffett made the bet, which includes all investment fees, in 2008 with the money managers who own Protégé Partners LLC. The winner of the bet will be able to donate at least $1 million in the charity of their choice at the end.
The results were reported first Wednesday by Fortune magazine. Buffett did not immediately respond to a message.
Buffett's chosen low-cost S&P 500 fund gained 2.08 per cent in 2011 to beat the five portfolios of hedge funds Protégé chose.
Through four years, the hedge funds are down 5.89 per cent. Buffett's index fund is down 6.27 per cent.