Anybody who was trading Taseko Mines (TGB) today, experienced a brief heart attack when the Canadian company lost nearly half its value around 2:33 pm Eastern time. In the blink of an eye, the stock price plunged from $7.20 to the mid $4 in what appeared to be another mini flash crash. Subsequently, it recovered, but only modestly, ending the day down about 10% from its open. What is odd is that not only did a circuitbreaker not get activated following the 40%+ drop, but that the exchanges have not canceled any of the trades, meaning that whoever started the selling avalanche is going to be stuck with their $4.58 sales. And as the charts below show, quite a few shares traded at the new baseline. What is oddest, is that there was absolutely no news in the market to cause this move, and to the best of our knowledge there was no rumors circulating either. Mootley Fool reports: "President and CEO Russell Hallbauer issued a statement saying that management "is unaware of any information that would cause the price of the Company's stock to change materially, as occurred on October 14, 2010." The stock had been trading up as much as 11% before the drop, and had hit a 52-week high. The upward movement was largely because of an upgrade from Jennings Capital analyst Peter Campbell. According to The Globe and Mail, Jennings issued a research note that was bullish on copper prices and upped its price target on Taseko by 28% to $10." Could this be the first time when an inexplicable flash crash driven by some jittery algo will not result in the exchanges handing back the HFT's forfeited money right back to them? We hope going forward every since robotic instability is punished appropriately. To all those whose 30-40% OTM limit buys got triggered, congratulations. Once again, we suggest readers establish limit buy positions 40% away from NBBO in stocks and sectors of preference, as the next flash crash is usually just a millisecond away. If lucky, just like in TGB, your trades will stay good.