NVIDIA CEO Jensen Huang is stepping down, leaving the artificial intelligence industry without its biggest champion and clouding the future of the chipmaker he built into an AI powerhouse.

Chief Financial Officer Colette Kress will take over as interim CEO as Nvidia looks for a permanent successor, considering both internal and external candidates, the company said on Thursday.

Huang, who co-founded Nvidia and is its fourth-largest investor with a stake of about 3.61%, will exit the board as well. Nvidia also named former Synopsys CEO and board member Harvey Jones as its first-ever board chair.

Its shares tumbled more than 12% in early trading, putting the company on course to lose about US$500 billion in market value and dragging the broader market lower.