Shares of technology companies fell amid concerns that artificial-intelligence companies would slam the brakes on the boom.

SpaceX Chief Executive Elon Musk and OpenAI Chief Executive Sam Altman backed Anthropic Chief Executive Dario Amodei's call for makers of AI models to slow development because of safety concerns.

Shares of chip makers fell sharply out of fears that a slowdown would weaken semiconductor demand. The PHLX "SOX" Semiconductor Sector index lost more than 5% of its value.

President Donald Trump pushed back on the idea of a slowdown in AI research, citing the need to stay ahead of Chinese competition.

"With China moving forward, it'll be interesting to see...if we can come up with [a blend of policies that] will protect humanity but also won't leave us in the dust," said J.D. Joyce, president of Houston financial advisory Joyce Wealth Management. "I have an idea it's going to be a tricky line to walk there."

Separately, The Wall Street Journal reported that OpenAI recently bought a startup developing higher quality cameras for smartphones.