Key Takeaways AI stocks had a volatile week as Wall Street reckoned with the implications of a sophisticated, cost-efficient AI model from Chinese start-up DeepSeek.Semiconductor stocks such as Nvidia and Broadcom sold off on Monday as investors worried DeepSeek's efficiencies would temper enthusiasm for AI infrastructure spending.

Entrepreneur Marc Andreessen, known for co-writing Mosaic, one of the world’s first web browsers, wrote Sunday on X that “DeepSeek R1 is AI’s Sputnik moment,” likening it to the space race between the U.S. and the Soviet Union and the event that forced the U.S. to realize that its technological abilities were not unassailable.

A frenzy over an artificial intelligence chatbot made by Chinese tech startup DeepSeek was upending stock markets Monday and fueling debates over the economic and geopolitical competition between the U.