Dario Amodei, the CEO of Anthropic, published an essay on September 14 warning that AI agents could become capable of seizing control of the entire internet within 6 to 12 months. The response from Wall Street was about as measured as you’d expect: a broad, global sell-off that wiped billions in market value from the companies building the very technology Amodei was describing.
What made the moment genuinely unusual wasn’t one executive sounding the alarm. It was the chorus. Sam Altman of OpenAI and Elon Musk of xAI both echoed Amodei’s concerns, creating a rare alignment among rivals who typically agree on almost nothing.
The damage across markets
Nvidia, the chipmaker that has essentially become the index fund for AI optimism, fell roughly 3% to 3.6%. AMD took a harder hit, dropping as much as 5.7%.
The Philadelphia semiconductor index, a benchmark that tracks chipmakers broadly, shed around 5.1% to 5.5% in early trading.
