Microsoft Capex Shortfall Puts IREN and Nebius Data Centers on Watch

Microsoft capex for the September quarter was $45.2 billion, roughly $5.5 billion below the $50.7 billion analysts expected, and the company says the gap came from AI data center capacity that outside providers did not deliver on time. This week, reporting from The Information and Business Insider pointed at two of those providers, IREN and Nebius, and the question now is whether the AI build-out is limited less by money than by how fast anyone can finish a building.

Chief financial officer Amy Hood said on Microsoft's October 28 earnings call that spending for calendar 2026 should be about $170 billion because of those third-party delays, with the missing capacity moving into the second half of Microsoft's fiscal year. Microsoft did not name the providers involved.

$45.2B

Microsoft capex, quarter to Sept 30

$50.7B

Analyst forecast, per StreetAccount

~$170B

Microsoft's calendar 2026 capex outlook

$9.7B

Microsoft's five-year IREN contract

Microsoft blamed late third-party capacity

The shortfall was not a decision to spend less. Hood tied it directly to suppliers, and she guided capex for the December quarter to more than $50 billion as the delayed deliveries arrive.

Demand was not the problem either. Azure revenue grew 48% even with the delays, Hood said, and Microsoft guided to 49% to 50% growth in constant currency for the current quarter, noting that some GPU-as-a-service contracts with third parties had slipped into the second half. Commercial remaining performance obligations, a measure of contracted future revenue, reached $677 billion, up 73%. Microsoft also produced $18.6 billion of free cash flow in the quarter, and Hood said the company expects to stay free cash flow positive for the fiscal year.

Investors rewarded the restraint, at least relative to peers. Over the week after earnings Microsoft shares fell 4.7%, while Alphabet dropped 12.1% and Oracle 6.3%, 24/7 Wall St. calculated. CNBC's Jim Cramer noted that Microsoft, the only hyperscaler that dialed back its capex plans, saw the best market reaction.

The Information points at IREN's Texas campus

On November 4, The Information reported, citing unnamed sources, that delays at IREN's site in Childress, Texas, led Microsoft to push back spending it had planned for the September quarter, according to a Stocktwits summary carried by Yahoo Finance. The report put Microsoft's underspend against its own plan at about $5 billion, and said it was unclear how much of that IREN's delays caused.

Microsoft agreed last year to spend $9.7 billion over five years renting Nvidia-powered servers at Childress. The deal is structured as four 50 megawatt deployments called Horizons. In an August filing, IREN said the first had been delivered and that it expected to deliver Horizons 2 to 4 later in 2026, TFTC reported.

Satellite images flag Nebius's New Jersey site too

Business Insider, citing satellite analysis from the research firm Aterio, reported that imagery through October 21 showed unfinished work at IREN's Texas campus, as summarized by RuntimeWire. Aterio also estimated that roughly 140 megawatts at Nebius's New Jersey project, which serves Microsoft, could slip into 2027. Microsoft has not linked either company to the shortfall, and the satellite readings are estimates from outside the fences, not company disclosures.

The stakes are large for both providers. Neoclouds borrow heavily to build capacity that a single big customer has agreed to rent, so a delay pushes back revenue while interest keeps running. We looked at how that model works in our neocloud stocks and debt analysis.

Neocloud stocks were already under pressure

The reports landed on a bad day for the group. IREN fell 11.4% in Wednesday's regular session and another 2.5% overnight, Stocktwits reported, leaving it down 45% for the year. Nebius and Applied Digital fell 7% each, and CoreWeave and Core Scientific 10% each, as investors priced in tighter data center rules after the Democratic midterm sweep, which we covered in AI data center stocks and the midterms. The same group had already dropped between about 4% and 6% in overnight trading after Microsoft's earnings on October 28.

What the AI Bubble Index says

The AI Bubble Index read 63.3 at the November 3 close, in the Normal band, down from 64.4 a week earlier. Fragility, at 72.2, sits well above Euphoria at 62.8, and the systemic risk family reads 71.8. Sentiment and attention remains the hottest family at 92.8, while the demand gap is the coolest at 39.6. The dashboard shows each family day by day.

Construction delays cut both ways for a bubble gauge. They slow the flow of new spending, which can cool the build-out, but they also stretch the timelines that heavily indebted builders were counting on. Our guide to AI infrastructure investment risks explains why execution, not just demand, matters, and our AI capex analysis puts Microsoft's spending next to its peers.