Elon Musk's SpaceX has a secret weapon: Anthropic is paying it $1.25 billion a month to keep training its AI

Elon Musk filed his S-1 to take SpaceX public. Buried inside it was a number that changed how Wall Street reads the entire company.

Anthropic, the AI company behind the Claude chatbot, will pay SpaceX $1.25 billion per month for access to the Colossus and Colossus II data centers through May 2029, with a discounted rate for May and June as the deal ramps up. Over its full term, the contract could deliver up to $45 billion in revenue to SpaceX, at a rate of approximately $15 billion per year. Either party can terminate with 90 days notice. Anthropic retains ownership of its AI models and data.

The deal became public the moment SpaceX's S-1 was filed with the Securities and Exchange Commission on May 20. Anthropic simultaneously announced it was expanding beyond Colossus 1, near Memphis, Tennessee, to Colossus 2 as well, scaling up Nvidia GB200 capacity throughout June. The two data centers together hold more than one gigawatt of computing power, originally built to run xAI's Grok chatbot. SpaceX signed Cloud Services Agreements with Anthropic in May 2026 for access to both facilities.

The significance of that monthly figure becomes clear when you hold it against SpaceX's total 2025 revenue of $18.67 billion. Anthropic's payments alone, at full run rate, would represent 80% of what SpaceX earned across all its businesses in its entire previous fiscal year. It is not a footnote. It is a revenue line that reshapes how any serious investor needs to model the company.

Starlink, the satellite internet business, remains the cleanest and most profitable segment. It generated $11.4 billion in revenue in 2025, up 49.8% year over year, with $4.4 billion in operating income and $7.2 billion in segment-adjusted EBITDA. Operating income grew 120.4%. Starlink now serves more than 10.3 million subscribers and generated $3.26 billion in revenue in the first quarter of 2026 alone, accounting for 69% of the company's total quarterly revenue.

The AI division, by contrast, is bleeding. SpaceX's AI business ran a $2.5 billion deficit in Q1 2026, contributing to a consolidated net loss of $4.3 billion on $4.7 billion in revenue. The Anthropic compute contract is designed to change that calculation. It turns the Colossus infrastructure from a cost center into a revenue-generating asset, and signals that SpaceX is positioning itself not just as a rocket company or a satellite internet provider but as a critical node in the global AI compute stack.

SpaceX has compressed its data center build time from 122 days to 66 days, dramatically faster than traditional operators constrained by land acquisition, power procurement, chip availability and cooling infrastructure. That execution speed is what makes the AI infrastructure thesis credible. If SpaceX can build data centers at half the time of competitors, and if Anthropic is willing to pay $15 billion a year for that capacity, other AI labs will be watching closely.

Tesla separately disclosed a $2 billion investment in SpaceX equity and a partnership to build the largest chip fabrication facility for vertically integrated semiconductor manufacturing at the Gigafactory Texas campus. The two Musk-controlled companies are integrating their technology and capital stacks in ways that make the boundaries between them increasingly difficult to draw.

The broader market context reinforces how acute the compute shortage has become. Nvidia reported Q1 fiscal 2027 revenue of $81.61 billion, up 85% year over year. Microsoft posted an AI business at a $37 billion annualized run rate, up 123% year over year. Alphabet guided 2026 capital expenditure of $175 to $185 billion with Google Cloud backlog above $460 billion. Every major technology company is racing to secure compute. Anthropic, which has no chips of its own, secured the next best thing: 300 megawatts of someone else's.

The SpaceX prospectus states that the key constraints in the continued growth of AI are physical, and that no other AI company has better control over the full physical stack. That claim, if it holds, turns the $1.75 trillion valuation from an aerospace bet into something considerably larger.