Doosan Fuel Cell shares fell as much as 12.85% after the company announced a 501.4 billion-won ($360 million) contract to supply phosphoric acid fuel cells for U.S. artificial intelligence data centers. The agreement with HyXiom, Doosan's U.S. subsidiary, runs through April 2028 and equals about 110% of last year's revenue. Investors sold into the announcement after the shares had rallied on expectations of the deal. Analysts highlighted the contract as Doosan Fuel Cell's first entry into the U.S. power market, where fuel cells can provide behind-the-meter electricity as AI data center expansion strains grid capacity. The company has annual production capacity of about 275 megawatts and is considering further expansion.