Anthropic Reveals It Will Pay SpaceX Up to $120.5B for AI Compute

Image: Elon Musk/X

Anthropic has agreed to spend up to $120.5 billion on SpaceX’s AI compute through 2029. The figure comes from the Claude maker’s IPO filing, and it adds a new name and a hard number to the GPU buildout SpaceX has been borrowing to fund.

Anthropic filed its Form S-1 registration statement with the US Securities and Exchange Commission on Monday, October 26, the paperwork a company needs before it can list its shares publicly. In it, Anthropic says that between May and October 2026 it “entered into and amended several agreements” with SpaceX.AI LLC, the wholly owned SpaceX subsidiary behind SpaceXSI, “to access compute powered by NVIDIA GPUs.”

Under those agreements, Anthropic says it will spend “an aggregate of up to $120.5 billion over terms extending into 2029.” Once all of the contracted capacity is delivered, which Anthropic expects in December 2026, payments come to roughly $3.1 billion a month, or about $37 billion a year. Fees are different while capacity is still ramping up.

The money isn’t fully locked in, though. The filing says the initial non-cancelable periods end in January 2027 and March 2027 under the separate agreements. After that, either Anthropic or SpaceX can cancel with 90 days’ written notice, so the full $120.5 billion is a ceiling rather than a guaranteed total.

That structure matches how SpaceX has described its compute business. In September, SpaceX’s CFO said the company had closed a hosting deal worth about $1.11 billion a month starting December 1, without naming the customer, and said these contracts come with early outs so SpaceX can take capacity back for its own Grok models.

For context, Anthropic is one of SpaceX’s direct rivals in AI, since its Claude models compete with Grok. Renting it GPUs turns that rivalry into a revenue stream for SpaceX while SpaceX keeps building its own training clusters. The filing also lists SpaceX alongside Microsoft, Nscale and Lambda as cloud providers giving Anthropic access to Nvidia GPUs, including Vera Rubin systems.

The deal helps explain how fast SpaceX’s business is growing. SpaceX’s third quarter results showed revenue up 161% to $14.6 billion, with $16.4 billion of capex going into the Super Intelligence business, and Elon Musk said on Sunday that SpaceX had secured $40 billion of debt for GPUs arriving in the first half of 2027.

There’s still plenty the filing doesn’t say. It doesn’t break down how much Anthropic has paid SpaceX so far, which data centers host the capacity, or whether the September hosting deal is one of these agreements. SpaceX hasn’t commented on the filing, and Anthropic’s IPO still needs SEC review before its shares can start trading.

Do you think renting compute to rivals like Anthropic is a smart move for SpaceX, or should it keep every GPU for Grok?