Wall Street closed out one of its roughest weeks since early summer on Friday, as a sell-off in artificial-intelligence-linked stocks hardened into a broader reassessment of how the AI buildout is actually being paid for. The S&P 500 fell 1.09%, or 84.62 points, to 7,659.44. The Nasdaq Composite, hit hardest, dropped 2.14%, or 572.99 points, to 26,140.03. The Dow Jones Industrial Average slipped a more modest 0.34%, or 175.28 points, to 52,002.41.
For the week, the Nasdaq fell roughly 4.5%, its steepest stretch since late June, and the S&P 500 lost nearly 2%. The Dow, cushioned by strength outside technology, still finished the week slightly higher. The losses snapped a run of record highs set earlier this year and capped a five-day stretch in which investors grew increasingly nervous about the debt piling up behind the data centers powering the AI boom, even as hotter-than-expected inflation data complicated the outlook for interest rates.
A credit question behind the AI boom
At the center of the unease is CoreWeave, the cloud-computing company that rents out Nvidia chips to AI developers including Anthropic and OpenAI. CoreWeave shares fell more than 15% on Wednesday and extended losses into Thursday's premarket session, as the yield on its 2031 bonds climbed above 16% in secondary trading and the cost of insuring its debt against default implied a nearly 63% probability of default within five years, up from roughly 30% a year earlier, according to Reuters reporting carried by Investing Live.
The company carries roughly $50 billion in debt, much of it secured against GPU hardware that can lose resale value quickly as newer chips arrive. Analysts have increasingly treated CoreWeave as a bellwether for a wider worry: that the data-center race to keep pace with AI demand is being financed less by free cash flow than by leverage. A review of the slump by Capital.com noted that CoreWeave's loans are collateralized by hardware whose value can fall sharply within a few years, a structure that leaves lenders more exposed if growth slows or chip generations turn over faster than expected.
CoreWeave's chief executive, Mike Intrator, pushed back on the market reaction, pointing to the company's roughly $104.2 billion revenue backlog as of June 30 as evidence it can meet its obligations.
The market reaction has been irrational.
Mike Intrator, CoreWeave CEO
Some analysts have sided with that view: UBS has argued the stock could still climb nearly 40% as debt fears ease. Others counter that a backlog of signed contracts is not the same as cash in hand, and that CoreWeave's structure — fixed debt payments against a business whose main asset depreciates — leaves little room for error if any large AI customer pulls back.
Inflation, oil, and a jumpy VIX
The CoreWeave scare landed on top of an already tense week for rates. A hotter-than-expected September inflation report pushed Treasury yields higher earlier in the week before they eased back Friday, as Federal Reserve Chair Kevin Warsh offered fresh comments on the path for interest rates. Rising oil prices, driven by escalating attacks on tankers near the Strait of Hormuz and Ukrainian strikes on Russian refineries, added another cross-current for traders already uneasy about input costs heading into the holidays.
Volatility followed the mood. CNBC reported that the Cboe Volatility Index, Wall Street's benchmark gauge of expected turbulence, pushed above 22 intraday Friday for the first time in roughly four months, with options traders positioning for the gauge to climb even higher in the weeks ahead.
The jitters were not confined to the United States. South Korea's Kospi, fresh off its worst week since 2008, gained 2% on Friday and snapped a seven-session losing streak — an early sign that at least some investors view the past week's losses as overdone rather than the start of a deeper unwind.
Markets face a fresh test next week, when Tesla and Meta are among the companies scheduled to report quarterly results. Investors will be watching closely for any sign that heavy AI-related capital spending is translating into profit, or whether this week's credit jitters spread further into the stocks and bonds of the companies building out the AI infrastructure boom.
