What 2010 event saw U.S. share prices plunge and rebound within minutes?

The 2010 event in which U.S. share prices plunged and rebounded within minutes was the Flash Crash.

On 6 May 2010, major U.S. stock indexes suddenly dropped and then recovered much of the loss. The Dow Jones Industrial Average briefly lost nearly 1,000 points, about 9%, in a matter of minutes. Many individual securities traded at extremely low or high prices before normal market conditions returned.

Investigations linked the episode to interactions among high-frequency trading, automated orders, and a large sell order in E-mini S&P 500 futures. The U.S. Securities and Exchange Commission and Commodity Futures Trading Commission concluded that the selling overwhelmed available liquidity and triggered further automated activity.

The Flash Crash differed from long-lasting historical crashes because its sharpest movement was extremely brief. It prompted reforms including single-stock trading pauses and wider market circuit breakers. A later criminal case against trader Navinder Singh Sarao concerned spoofing activity, but the event involved broader market mechanics than one person alone.