U.S. stock markets tumble as investors worry about DeepSeek

China may be about to burst Silicon Valley’s A.I. bubble — and Wall Street is freaking out.

U.S. tech stocks plunged on Monday, amid a wider market selloff. The culprit: DeepSeek, a Chinese artificial intelligence company that last week introduced a new — and low-cost — model into the red-hot A.I. tech market.

DeepSeek on Monday morning became the most-downloaded free app on Apple’s U.S. app store — dethroning OpenAI’s ChatGPT in the process.

Shares of Nvidia, the chip company whose A.I. technology has made it into one of the most valuable companies in the world, dropped more than 13 percent by late morning on Monday. Rival chip companies, including Arm and Broadcom, also plunged, dragging down the major indices. The tech-heavy Nasdaq fell almost 600 points, or nearly 3 percent, by late morning.

Google, Microsoft, Apple, Meta, and other big tech companies have poured billions of dollars into building up their artificial intelligence capabilities, fueling a Silicon Valley arms race. But now investors are calling these pricey investments into question: DeepSeek says it costs less to train its models, and its open-source A.I. assistant uses less advanced chips than rivals’ models do.

At least investors will soon get to grill Big Tech companies about DeepSeek and their overall A.I. strategies. Four of the so-called Magnificent Seven tech stocks — Meta, Apple, Microsoft, and Tesla — are all due to report quarterly results this week.