AI Warning and Oil Shock Push U.S. Stocks Lower

A 5% Treasury yield and crude oil above $100 a barrel proved a potent combination for Wall Street on Monday, pushing investors out of some of the market’s most crowded trades.

The S&P 500 fell 0.5% to 7,619.98, while the Nasdaq Composite dropped 0.6% to 26,186. The declines were modest compared with the early selloff, when the Nasdaq was down more than 1%, but semiconductor shares absorbed the heaviest damage. Nvidia lost about 3.4%, Marvell Technology fell roughly 7.5%, and Intel dropped around 5.5%, according to market reports.

The immediate catalyst was an unusual chorus from the companies building the frontier of artificial intelligence. Anthropic CEO Dario Amodei called for a slower pace of model development in a weekend essay, arguing that safety systems are not advancing quickly enough. OpenAI CEO Sam Altman separately said the industry may need to slow down and coordinate on safeguards, while Elon Musk’s xAI also joined the broader warning.

Markets treated the comments as a threat to the spending cycle that has powered chipmakers, server suppliers and data-center infrastructure stocks. The concern is not that companies will abandon AI investment overnight. It is that a pause in the race for ever-larger models could delay new hardware orders, trim capital-expenditure plans or force investors to reassess valuations built on years of uninterrupted growth.

Oil added a second layer of pressure. Brent crude settled near $105.68 a barrel after briefly approaching $110, as fresh attacks on Saudi energy infrastructure and ships in the Middle East intensified supply fears. The move lifted inflation expectations and helped push the 10-year Treasury yield to 5% for the first time since 2023.

That matters most for technology shares, whose distant profits become less valuable when borrowing costs rise. It also complicates the Federal Reserve’s policy debate ahead of its September 16 meeting. Software stocks held up better than chipmakers, suggesting investors were rotating within technology rather than abandoning the sector altogether. For now, the market is testing whether AI’s extraordinary spending boom can survive a slower technological sprint and a more expensive macroeconomic backdrop.