The 2010 Flash Crash caused an exceptionally rapid plunge in U.S. stock prices on May 6, 2010.
During the afternoon of May 6, major U.S. equity indexes suddenly dropped and then recovered much of the loss within minutes. The Dow Jones Industrial Average fell roughly 1,000 points, or about 9%, at its intraday low. Individual securities experienced even more extreme temporary price movements.
Investigations concluded that the event involved a combination of market conditions, automated trading, and a large sell order in E-mini S&P 500 futures. The exact market mechanics were complex, and the crash exposed weaknesses in the interaction between electronic exchanges and high-frequency trading systems.
The episode differed from a conventional bear market because its most dramatic movement occurred in minutes rather than over months or years. Regulators later introduced measures such as circuit breakers and limit-up/limit-down mechanisms to reduce the risk of disorderly price movements. The date is sometimes confused with the 1987 Black Monday crash, which was a separate worldwide market event.