AI and chip stocks tumble, S&P 500 dips 0.3%

Major U.S. stock indexes experienced another volatile session on Tuesday, June 9, as a renewed selloff in artificial intelligence and semiconductor stocks erased early gains. The S&P 500 fell 0.3% to close at 7,386.65, while the Nasdaq Composite dropped 1% to 25,678.82. The Dow Jones Industrial Average bucked the trend, adding 86 points, or 0.2%, to finish at 50,872.11.

The day was marked by dramatic intraday swings, with the S&P 500 careening between an initial gain of 1% and a midday loss of 2.3% before paring losses. The weakness was concentrated in the technology sector, where companies selling chips, memory, and other AI building blocks reversed early advances. Micron Technology, for example, swung from a 4% jump to a 10% plummet before closing down 1.4%. This followed a 9.9% surge on Monday and a 13.3% plunge last Friday. Marvell Technology dropped 7.6%, and Advanced Micro Devices sank 3%. Nvidia, the market's largest company by value, also declined, weighing heavily on the S&P 500.

The sharp moves extended a period of intense volatility for AI-related stocks, which have seen massive gains this year. Micron's stock has tripled in 2026, raising questions about whether the...