In 2007, Warren Buffett challenged finance professionals in the hedge fund industry to accept a bet that Buffett described in his 2016 letter to shareholders of Berkshire-Hathaway (see p. 21-21):
In Berkshire's 2005 annual report, I argued that active investment management by professionals – in aggregate – would over a period of years underperform the returns achieved by rank amateurs who simply sat still. I explained that the massive fees levied by a variety of "helpers" would leave their clients – again in aggregate – worse off than if the amateurs simply invested in an unmanaged low-cost index fund.
Subsequently, I publicly offered to wager $500,000 that no investment pro could select a set of at least five hedge funds – wildly-popular and high-fee investing vehicles – that would over an extended period match the performance of an unmanaged S&P-500 index fund charging only token fees. I suggested a ten-year bet and named a low-cost Vanguard S&P fund as my contender. I then sat back and waited expectantly for a parade of fund managers – who could include their own fund as one of the five – to come forth and defend their occupation. After all, these managers urged others to bet billions on their abilities. Why should they fear putting a little of their own money on the line?