(Sept 15): A sell-off in chipmakers dragged down stocks as leaders of artificial-intelligence giants proposed slowing the technology’s development, with elevated oil prices also weighing on sentiment.

The rout in powerhouses like Nvidia Corp and Broadcom Inc sent a semiconductor gauge down by 5.9% on Monday. The Nasdaq 100 fell 0.8%. Bank of America Corp led losses in financial shares on chief Brian Moynihan’s trading revenue warning. Brent crude topped US$105, raising concern about inflation before the Federal Reserve decision. Treasury 10-year yields hovered near 5%.

A 3,800-word missive by Anthropic PBC chief executive officer Dario Amodei — which was endorsed by OpenAI CEO Sam Altman and SpaceXAI CEO Elon Musk — said development of the most-advanced systems must be slowed in order to prevent AI slipping beyond human control and inflicting catastrophic harm.

Microsoft Corp’s AI researchers have released a new set of guiding tenets that place limits on the company’s development of cutting-edge AI models. The 15,000-word manifesto boils down to five words: People matter more than AI.

President Donald Trump attacked Anthropic’s chief for urging a slowdown in AI development, intensifying his opposition to new guardrails. He blamed a “sick conspiracy” for voter backlash on AI data centers and increased concern about frontier models and added that “the only one that is happy about it is China.”

If the latest developments push out the timing of promised AI returns, it makes sense that investors would become less enthusiastic, according to Matt Maley at Miller Tabak.

“What really happened? Surely something big enough to spook Dario, Sam, and Elon into rare agreement,” said Giuseppe Sette at Reflexivity. “Whatever it was, it was probably stopped at the last minute, just before disaster struck. With China in the race, though, we don’t expect any major slowdown.”

As for any retracement in AI stocks, Sette noted that’s simply a buying opportunity. “Concerns on AI deployment could be a sentiment negative for the AI value chain,” said Justin Post and Nitin Bansal at Bank of America Corp. “Despite potential concerns, we continue to believe AI capacity will have strong multi-year demand.”

At HSBC, Max Kettner says calls for a slower AI buildout and resulting fears for the tech sector are “overblown.” This could actually help profitability of AI companies eventually, he said.

“Whether calls to pace advanced model development will gain traction across the industry remains uncertain, but we believe they are more aimed at shaping a regulatory framework acceptable to leading AI labs,” said Ulrike Hoffmann-Burchardi at UBS Chief Investment Office. “We therefore expect AI investment to continue.”

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Uploaded by Jason Ng