Nebius Group NV closes down 17%, worst single-day drop since July

A single-session drawdown of this size at an AI infrastructure name is a sentiment signal as much as a company event, and the absence of an obvious operational catalyst in the item makes the move harder to attribute. For a sector where valuations lean heavily on forward buildout expectations, sharp repricing tends to spill over to peers and to the financing conversations surrounding data-center capacity. The open question is whether this proves an isolated flush or the start of a broader re-rating across AI-linked equities.