By Heard Editors

What Happened in Markets Today:

The U.S. will impose an additional 10% tariff on imports from China. President Trump attributed the move to China's role in the fentanyl trade. The move, slated to take effect Tuesday, doubles up on the previous 10% additional tariff Trump placed on Chinese products earlier this month.

Nvidia shares fell 8.5%. The decline took place even as the AI semiconductor maker reported strong sales of its new Blackwell chips. The report showed that generative artificial intelligence continues to drive the company once primarily known for its PC gaming chips, Heard on the Street's Dan Gallagher wrote. But analysts pointed to narrower profit margins and worry about Nvidia's sales in China.

Stocks slipped amid the tariff threats and Nvidia's shaky performance. The tech-heavy Nasdaq Composit fell 2.8%, the S&P 500 fell 1.6% while the Dow closed down 0.5%.

Moderna shares fell 7.4%. The decline came after reports that federal health officials are re-evaluating the company's $590 million contract to help develop a bird-flu vaccine. Moderna was awarded the contract from the U.S. Department of Health and Human Services in January during the Biden administration to accelerate development of its mRNA-based vaccine, and as part of an effort to address growing concerns of a bird flu pandemic in humans.

More Americans filed for initial jobless benefits last week. The week through Feb. 22 brought 242,000 initial jobless claims, compared with 220,000 a week earlier. The report followed disappointing home sales data earlier this month**.**

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(END) Dow Jones Newswires

February 27, 2025 17:04 ET (22:04 GMT)

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