A hotter-than-expected September inflation report hammered AI-infrastructure stocks on Wednesday, wiping out roughly $80 billion in combined market value as investors braced for higher borrowing costs in the most debt-fuelled corner of the market.
Inflation ran hotter than forecast
The consumer price index rose 0.6% in September from August, pushing the 12-month inflation rate to 3.7%, according to reports — above the 3.6% economists polled by Dow Jones had expected. Core CPI, which excludes food and energy, rose 0.3% on the month and 2.6% from a year earlier, each a tenth of a point above forecasts. Energy supplied the shock: gasoline prices jumped 9.1% in the month, accounting for more than half of the headline gain, while fuel oil surged 15.3%.
Debt-funded AI names took the hit
The sell-off concentrated in the companies borrowing hardest to build AI capacity. CoreWeave fell about 16%, Nebius about 11%, Oracle about 9% and Dell Technologies about 11%, while the S&P 500 dropped 1.1% and the Nasdaq composite 1.9% — the worst session for both since July. Barclays downgraded Dell and two other enterprise-hardware stocks on the day.
Wall Street had already been bracing for bank earnings under surging bond yields, and the inflation data confirmed those fears — even as Goldman Sachs turned bullish on global stocks just days earlier, a call the hot print immediately put under pressure. In credit markets, the yield on CoreWeave’s 2032 notes leapt to nearly 15%, and the bonds — sold at par four months ago — fell below 78 cents on the dollar, into distressed territory.
The Federal Reserve raised its target range to 3.75%–4.00% in September — its first increase since 2023 — and meets again on October 27–28. The firming core reading revived bets on further tightening, piling pressure on every dollar of AI infrastructure financed with debt. The Fed’s October survey of regional business conditions found the impact of higher oil prices in reports from all twelve districts.
CoreWeave’s chief executive, Michael Intrator, pushed back in a staff memo, arguing that markets can move irrationally and that the company’s order backlog more than covers its debt. Whether that backlog holds will decide if Wednesday’s rout was a buying opportunity — or the moment AI’s debt bill finally came due.
