How long is Anthropic’s lease with SpaceX? Opinions vary.

Earlier this month, xAI signed a major computing deal with Anthropic, pledging billions of dollars per month for the exclusive use of the company’s Colossus cluster. It was a coup for both companies, bringing much-needed revenue to xAI and helping Anthropic catch up in the never-ending race for computers.

But this morning on XElon Musk downplayed exactly how much SpaceX had committed to the deal.

“SpaceX has not committed to leasing Colossus in years, although it is possible that it will,” he said in response to a user. “This is a 180-day lease with 90 days’ notice, then mutually cancelable. The short term was our request, not Anthropic’s. We won’t leave them hanging and provide a reasonable off-ramp, but if compute capacity gets super tight, I said we might need it again at some point.”

Musk’s statement directly contradicts SpaceX’s recent S-1 filingwhich confirms the standard 90-day notice but presents the deal as a three-year agreement. Page F-62 of the filing reads:

On May 3, 2026, the company entered into a cloud services agreement with Anthropic PBC, a public utility AI research and development company, regarding access to computing capacity. Under this agreement, the customer has agreed to pay a monthly fee through May 2029, with capacity ramping up at a reduced rate in May 2026. The agreement can be terminated by either party with 90 days’ notice. Customer retains ownership and intellectual property rights to the content, AI models and related data.

The key point here is that Anthropic “has agreed to pay a monthly fee through May 2029” – a fairly basic description of a three-year lease. The same language is repeated on F-96 and in slightly varied form (“the customer has agreed to pay us $1.25 billion per month through May 2029”) on pages 13 and 146, so it’s not like there was a typo.

xAI did not respond to a request for clarification.

Maybe we can quibble about whether Anthropic agreeing to pay for a service means the same thing as SpaceX agreeing to provide that service, but that’s not usually what “lease” means. And why would you use a one-way lock-in if both parties can terminate the deal with three months’ notice?

I don’t have the deal in front of me, so I don’t know what it says – nor does it SpaceX nor Anthropic says something about the duration of the deal in their announcements. Still, there should be a fairly simple fact here, and it’s not something you want to make false statements about during a company’s slow period.

As always, we have to keep in mind that the SEC probably won’t do anything – and even if they did, Elon probably wouldn’t care. But this kind looks similar a material misrepresentation in the marketing of a securitywhich is bad karma to say the least.

Sean O’Kane contributed reporting to this article.