In 2006, JPMorgan designed some complex derivatives to allow clients to enhance their bets on funds run by the Fairfield Greenwich Group, which basically existed to invest with Bernard Madoff. The deal called for the bank to invest some of its own money with Madoff.

But, according to the New York Times, JPMorgan suddenly started pulling its funds from Madoff, without telling their customers, who eventually got stuck with some huge losses. Investors now think that if JPMorgan discovered issues with Madoff, it should have informed them. That would certainly have saved them a lot of misery.

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