Elon Musk Leases World's Largest Supercomputer to Anthropic

Elon Musk leased the world's largest supercomputer to Anthropic on Wednesday, three months after he wrote on X that the company was "evil," "misanthropic," and that the AI lab hated Western civilization. The supercomputer, known as Colossus 1, contains roughly 220,000 Nvidia GPUs.

It was built in 2024 to train Grok, Musk's AI assistant. Grok has not filled the facility's capacity. According to estimates from an analyst at New Street Research, the lease will generate $3 billion to $4 billion in annual revenue for SpaceX, with more than $2.5 billion in cash profit.

The margins are high because the data center is already built and the main operating costs are electricity and staffing. "He’s not going to want multiple billions of dollars of GPUs sitting idle," the analyst told Fortune. " The announcement coincides with the dissolution of Musk's AI company xAI into SpaceX, forming SpaceXAi.

SpaceX is expected to begin its public roadshow next month after filing a confidential S-1 on April 1. The company is targeting a valuation between $1.75 trillion and $2 trillion.

The deal positions SpaceX as a provider of cloud infrastructure with a marquee AI customer. This gives the upcoming IPO a credible cloud-infrastructure business that it lacked a week ago. A former head of Google Cloud AI, now CEO of a defense AI startup, told Fortune that controlling data centers currently means controlling the application of artificial intelligence.

The executive described the arrangement as a "wedding of convenience" that may leave both sides stressed. SpaceX would capture the 30%-plus margins that frontier AI labs currently pay to providers such as AWS, Microsoft Azure or Google Cloud. Analysts told Fortune that framing SpaceX as the fourth hyperscaler could support a higher valuation multiple for the IPO, closer to those of Alphabet, Microsoft and Amazon than to Boeing or Lockheed Martin.

" The clause was not included in the formal press release and it is unclear whether it appears in the contract. Anthropic is on track to generate more than $40 billion in annualized revenue, far outpacing Grok's estimated contribution of less than $1 billion.

The lease addresses Anthropic's need for additional compute and SpaceX's excess capacity. A managing partner at Deepwater Asset Management put the odds of the deal still existing in two years at 80 percent. The executive cited Musk's history of changing his mind as the main risk factor.

The former Google Cloud AI executive said frontier AI labs typically avoid single-sourcing their compute infrastructure and will likely develop contingency plans. Both parties will continue to face pressure in the rapidly evolving sector.