Nebius expects $10B in committed customer prepayments for 2026

The shift away from ARR as a headline metric is the tell: Nebius is asking the market to underwrite contracted backlog rather than run-rate revenue, a framing that suits a business whose cash arrives ahead of capacity. Prepayments of this scale are effectively customer-funded buildout, which lowers financing risk but concentrates exposure to a handful of large buyers. The disclosure that some third-party capacity slips into the first half of next year is the quiet caveat — delivery timing, not demand, is the constraint. Whether those prepayments convert into recognized revenue on schedule is the open question.