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How did this day trader lose so much?
Learn something new every day... I found this interesting and thought I'd throw my 2c in. Good description (I hope) from Short Selling: What is Short Selling First, let's describe what short selling means when you purchase shares of stock. In purchasing stocks, you buy a piece of ownership in the company. You buy/sell stock to gain/sell ownership of a company. When an investor goes long on an investment, it means that he or she has bought a stock believing its price will rise in the future. Conversely, when an investor goes short, he or she is anticipating a decrease in share price. Short selling is the selling of a stock that the seller doesn't own. More specifically, a short sale is the sale of a security that isn't owned by the seller, but that is promised to be delivered.  Still with us? Here's the skinny: when you short sell a stock, your broker will lend it to you. The stock will come from the brokerage's own inventory, from another one of the firm's customers, or from another brokerage firm. The shares are sold and the proceeds are credited to your account. Sooner or later, you must "close" the short by buying back the same number of shares (called covering) and returning them to your broker. If the price drops, you can buy back the stock at the lower price and make a profit on the difference. If the price of the stock rises, you have to buy it back at the higher price, and you lose money. So what happened? The Plan The Reality Lesson I never understood what "Shorting a stock" meant until today. Seems a bit risky for my blood, but I would assume this is an extreme example of what can go wrong. This guy literally chose the wrong time to short a stock that was, in all visible aspects, on the decline.  How often does a Large Company or Individual buy stock on the decline... and send that stock soaring? How often does a stock go up 100% in 24 hours? 600%?  Another example is recently when Oprah bought 10% of Weight Watchers and caused the stock to soar %105 in 24 hours. You would have rued the day you shorted that stock - on that particular day - if you believed enough to "gamble" on it going down in price.