Max Keiser - journalist, former Wall Street broker and options trader, and inventor of the software which is now being used for high frequency trading - claims that the big banks retroactively allocate losing trades to their clients, and keep the winning trades for their own proprietary trading desks:

This is the second time in the couple of weeks that Keiser has made this allegation. When he first brought this up, Keiser said that he has first-hand knowledge of this unlawful activity because - when he was a trader - he and everyone else did the same thing.

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