The shocking success of a new model from a mysterious Chinese lab has America questioning its leadership of the sector.

Global chip stocks slumped Monday on DeepSeek revealing it had developed AI models that nearly matched American rivals despite using inferior chips.

The S&P 500 fell 1.9% Monday. Big Tech stocks took some of the heaviest losses, with Nvidia down 17.6%, and they dragged the Nasdaq composite down 3.3%.

In Amsterdam, Dutch chipmaking equipment company ASML slid 7%. In Tokyo, Japan’s Softbank Group Corp. lost 8.3% to pull closer to where it was before leaping on an announcement trumpeted by the White House that it was joining a partnership to invest up to $500 billion in AI infrastructure.

Wall Street is tumbling on fears the big U.S. companies that have feasted on the artificial-intelligence frenzy are under threat from a competitor in China.

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.

Wall Street is tumbling on fears the big U.S. companies that have feasted on the artificial-intelligence frenzy are under threat from a competitor in China. The S&P 500 fell 1.9%