The Nasdaq stock exchange was shut down for three hours Thursday because of a technical problem with a system for disseminating stock prices. Here's a look at other glitches that have affected stock trading. Twice, Nasdaq's trading was interrupted by power problems caused by squirrels getting electrocuted.
— KNIGHT CAPITAL, Aug. 1, 2012. Trading in 140 stocks on the New York Stock Exchange was thrown into chaos because of a software glitch at Knight Capital, causing sudden price swings. Knight was on the hook for many of the stocks that its computers accidentally ordered, and it teetered near bankruptcy before being bought by the high-speed trading firm Getco.
— FACEBOOK IPO, May 18, 2012. The highly anticipated initial public offering of Facebook was marred by a series of technical problems on the Nasdaq. The start of trading was delayed and many traders didn't know if their orders went through. A year later, Nasdaq agreed to pay a $10 million penalty to settle federal civil charges after regulators said its systems and decisions disrupted the offering. The Nasdaq also paid $62 million in reimbursements to investment firms that lost money because of the problems.
— BATS's IPO CANCELED, March 23, 2012. BATS Global Markets, a Kansas-based company that competes with Nasdaq and the New York Stock Exchange in offering stock trading services, canceled its own IPO after a series of technical snafus. The company's CEO, Joe Ratterman, issued a public apology.
— "FLASH CRASH," May 6, 2010. The Dow Jones industrial average plunged hundreds of points in mere minutes. A months-long investigation by regulators concluded that the sudden drop occurred when a trading firm executed a computerized selling program in an already stressed market. The trade, worth $4.1 billion, led to a chain of events that ended with traders swiftly pulling their money from the market, the review found.
— SQUIRREL-RELATED DELAYS. Trading was delayed twice on the Nasdaq, seven years apart, because of squirrels getting electrocuted on electrical equipment, leading to power outages. On Dec. 10, 1987 a squirrel carrying a piece of aluminum foil was electrocuted, and on Aug. 1, 1994 a squirrel died after apparently chewing through a power line near the Nasdaq's computer center in Trumbull, Conn.