The Flash Crash was the rapid U.S. stock-market plunge and partial recovery on May 6, 2010.
During the afternoon of May 6, major U.S. equity indexes dropped very quickly before recovering much of the loss. The Dow Jones Industrial Average briefly fell about 1,000 points, or roughly 9 percent, within minutes. Many individual securities also experienced unusually extreme price movements.
Investigations found that automated trading played an important role. The U.S. Commodity Futures Trading Commission and Securities and Exchange Commission described how large selling, high-frequency trading, and liquidity withdrawal interacted. The event was not the same as the long decline after 1929 or the 2008 financial crisis; it was a short-lived market-structure shock.