Fears of an AI bubble are intensifying in Silicon Valley, even as OpenAI’s Sam Altman insists “there’s something real happening here.” The Bank of England, IMF and JP Morgan’s Jamie Dimon have sounded caution, while data show AI-linked firms driving 80% of U.S. market gains and spending poised to hit $1.5tn. Scrutiny focuses on a web of deals around OpenAI—spanning Nvidia, AMD, Microsoft and Oracle—prompting allegations of “circular” financing. OpenAI’s revenues are rising but it remains unprofitable. Veterans warn a break could hit the wider economy, though others say timing a bubble is impossible.

Prepared by Christopher Adams and reviewed by editorial team.