The 2010 market event in which major U.S. indexes plunged and recovered within minutes amid automated-trading turmoil was the Flash Crash.
On May 6, 2010, U.S. equity markets experienced an exceptionally rapid decline. The Dow Jones Industrial Average briefly lost nearly 1,000 points, then recovered much of the fall before the trading day ended. Prices in individual stocks and exchange-traded funds became extremely disordered.
Investigations identified a combination of market stress, high-speed algorithmic trading, and a large automated sell order. The U.S. Securities and Exchange Commission and Commodity Futures Trading Commission later concluded that a trader’s sell algorithm contributed significantly, while the broader market structure amplified the move.
The Flash Crash was not a conventional recession-driven crash. Its defining feature was speed: prices fell and rebounded in minutes. Regulators subsequently introduced or strengthened controls such as circuit breakers and limit-up-limit-down mechanisms to reduce the risk of similar disorder.