·Banks look unstoppable, but JPMorgan CEO Jamie Dimon sees a 30% chance of a correction: ‘I’m far more worried than others’By Marco Quiroz-GutierrezBy Marco Quiroz-GutierrezReporterMarco Quiroz-GutierrezReporterRole: ReporterMarco Quiroz-Gutierrez is a reporter for Fortune covering general news.SEE FULL BIO Jamie Dimon, chief executive officer of JPMorgan ChaseSarmento Matos—Bloomberg/Getty ImagesJamie Dimon, CEO of the world’s most valuable bank and architect of the “fortress balance sheet” that helped JPMorgan emerge unscathed from the 2008 financial crisis, believes investors are downplaying the risk of a major market correction—one that could slash stocks by a third.
With stock market valuations and concentration at record highs, some high-file leaders OpenAI CEO Sam Altman as well as institutions such as the Bank of England have warned froth in the market and the possibility that the AI bubble may soon burst.
Dimon, who in his two decades at the helm of JPMorgan has built a reputation for operating cautiously and making smart moves the bargain purchase of First Republic Bank in 2023, warns the stock market isn’t appriately pricing in the risk of a downturn.
“I am far more worried that than others,” Dimon told the BBC in an interview published Wednesday. “I would give it a higher bability than I think is bably priced in the market and by others.
So if the market’s pricing in 10%, I would price in—I would say it’s more 30 [percent].” Dimon, in his most recent s, said the timing of the end of the rally is difficult to predict.
It’s possible a stock market downturn could hit in six months. Yet the stock market rally could also hold on for another two years, he noted. “Bull could go on a lot longer than you think,” he said.
The JPMorgan CEO said he has studied other periods of market euphoria the dotcom crash, and found the only way to get a sense of when a bubble is coming to an end is through high valuations, otherwise: “It’s really impossible to tell the burst,” he said.
He acknowledged that by many measures valuations are high, which creates an element of risk.
Part of what has led to this situation is the cheap money flowing into in recent years thanks to the ballooning national debt used to fuel stimulus as well as quantitative easing during the COVID pandemic.
Dimon added some of the investment in AI will “bably” be wasted money, and some investors in the nology may end up worse off. “AI is real.
AI in total will pay off, just cars in total paid off, TV in total paid off,” Dimon said.
“But most people involved in it didn’t do well.” The current AI-fueled optimism has led the S&P 500 to 33 record highs in 2025, just short of the 57 record highs hit in 2024 with three months left in the year.
In terms of stock concentration, the 10 largest companies in the S&P 500 now make up a record 40% of the index’s market capitalization. The S&P 500 is up 14.8% year to date as of Thursday.
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