In a mere 3 seconds, Qualys, a $350mm market cap company providing IT security solutions, was rendered worthless by a rogue algorithm with an apparent sense of humor. The stock opened around $11 but at 0935ET, Johnny 5 decided it was time for the take-down and almost instantaneously the stock, QLYS, crashed to $0. Seven seconds later, all was well in the world of IT security solutions once again as $11 was recovered. Of course, in the meantime, every stop was triggered and any belief in the stability of the market was destroyed - but hey, the exchanges got their data fees.
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This is the high-speed casino that your retirements are 'invested' in...
Source: Nanex [3] [3]