AI Fears, Oil and 5% Yields Pressure Wall Street

A brief move above 5% in the 10-year Treasury yield was enough to remind investors that Monday’s market problem was bigger than a bad session for technology stocks.

The S&P 500 fell 0.5% on September 14, while the Dow Jones Industrial Average slipped 0.3% and the Nasdaq Composite declined 0.6%. The Nasdaq had been down more than 1% earlier in the day, but gains in software, cybersecurity and several nontechnology groups helped contain the damage.

Semiconductors absorbed the sharpest blow. Nvidia dropped 3.4%, while Intel fell 5.6%, AMD lost about 5% and Marvell Technology declined more than 6%, according to market reports. The selling followed weekend warnings from Anthropic Chief Executive Dario Amodei, OpenAI Chief Executive Sam Altman and xAI founder Elon Musk that frontier artificial-intelligence development should slow while safety controls catch up.

That message struck directly at the assumptions supporting the AI infrastructure trade: ever-larger models, relentless data-center construction and sustained demand for advanced chips. It did not yet amount to a cancellation of spending plans. But with semiconductor valuations already stretched, investors did not need much encouragement to take profits.

Cybersecurity stocks moved in the opposite direction. CrowdStrike climbed roughly 14% and Palo Alto Networks gained about 13%, as traders interpreted the AI safety debate as a potential catalyst for security software rather than a threat to technology spending broadly.

Oil added a second layer of pressure. West Texas Intermediate settled near $102 a barrel, up about 2%, as supply disruptions tied to the Iran conflict and the shutdown of a Saudi pipeline intensified concerns about inflation. Higher crude prices pushed bond yields upward by reviving fears that central banks will have to keep policy restrictive for longer.

The two-year Treasury yield closed around 4.66%, its highest level in two years, while the 10-year briefly crossed 5% before easing. Markets were already pricing a strong probability of a 25-basis-point Federal Reserve rate increase on Wednesday, September 16.

Bank stocks supplied another warning sign. Bank of America fell about 5% after Chief Executive Brian Moynihan said third-quarter investment-banking fees could decline at least 10%, with trading revenue roughly flat from a year earlier. The message was clear: expensive money and geopolitical uncertainty are beginning to reach corporate activity, not just equity multiples.