Wall Street’s superstars are tumbling Monday as a competitor from China threatens to upend the artificial-intelligence frenzy they’ve been feasting on.
The S&P 500 was down 1.9% in midday trading and heading for its worst day in more than a month. Big Tech stocks took some of the heaviest losses, with Nvidia down 17.6%, and they dragged the Nasdaq composite down 3.3%.
Stocks outside of AI-related industries held up much better, though, and the Dow Jones Industrial Average was down just 58 points, or 0.1%, as of 11:40 a.m. Eastern time. The Dow, which has much less of an emphasis on tech than the S&P 500 and Nasdaq, had briefly been on track for a small gain earlier in the morning.
The shock to financial markets came from China, where a company called DeepSeek said it had developed a large language model that can compete with U.S. giants but at …