Why is Nebius stock sliding today?

Nebius stock slid 4.7% in morning trading as a disappointing capital expenditure report from Microsoft sent shockwaves through the AI infrastructure sector, pulling neocloud names sharply lower. Microsoft disclosed quarterly capex of $45.2 billion — up roughly 30% year-over-year but well short of the $50.7 billion analyst consensus — with the company attributing the gap partly to timing differences related to third-party capacity delivery and payment. Investors interpreted the miss as a potential sign that hyperscaler spending on external AI compute — the lifeblood of neocloud operators like Nebius — could be under pressure.

The decline is compounded by sector-wide vulnerabilities that have weighed on Nebius throughout October. Concerns about the sustainability of AI infrastructure financing, dilution risk tied to large convertible-note issuances, and elevated short interest have kept the stock on edge. A Form 4 filing by Director Arne Grimme, dated October 27, added a minor note of insider-activity scrutiny, though it was not identified as a primary driver of today’s move.

Today’s drop comes after a strong two-session rebound in which Nebius surged on news that it had raised approximately €250 million for its planned data center near Lille, France, and secured a $3.5 billion credit facility. The Nasdaq composite fell 1.4% today as mixed Big Tech earnings — including the Microsoft capex miss — tested investor conviction in the AI trade, while the S&P 500 and Dow Jones also declined modestly. Nebius’s neocloud peers CoreWeave and IREN moved lower in sympathy, underscoring that this is a sector-wide reaction rather than a company-specific event.

Taken together, the Microsoft capex shortfall acted as the immediate trigger for today’s move, amplified by the neocloud sector’s fragile sentiment and Nebius’s elevated beta following weeks of volatile trading. The stock remains well above its 52-week low of $73.52 but has pulled back sharply from its 52-week high of $299.86, with investors continuing to weigh the long-term promise of AI infrastructure build-out against near-term financing and demand risks.