Bloomberg just revealed that Anthropic accounted for 34.5% of SpaceX’s $14.575B third-quarter revenue, overtaking the US government as its biggest customer.

SpaceX’s filing labels the client only “Customer B”

The payments rent Nvidia GPU capacity at SpaceX’s Memphis data centers, through a compute-leasing business that also serves Google.

A year earlier, Customer B was under 10% of revenue; now it supplies about two-thirds of the AI segment’s $7.56B, which posted its first profit.

Anthropic’s S-1, filed October 26, puts the SpaceX arrangements at up to $120.5B into 2029, about $3.1B a month once all capacity is delivered in December 2026, and either side can terminate on 90 days’ notice after initial periods ending in January and March 2027.

Also, Anthropic’s Google, Amazon and Microsoft commitments are stated as minimums of at least $114.5B, $110B and $44.9B, while the SpaceX number is a maximum, which makes the SpaceX deal easier to shrink than its hyperscaler contracts.