Nasdaq plans to wipe some of yesterday's wildest stock market activity from the books. The stock exchange operator is canceling trades of 286 stocks that went up or down by over 60% in the 20 minutes beginning at 2:40 pm, Reuters reports. The shares affected include Accenture, which fell by more than 99% to a penny before rebounding to close at $41.09. The decision to cancel the trades can't be appealed, said Nasdaq officials.
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