Anthropic's S-1 Reveals Its Own Data Centers and Makes $3.1 Billion a Month of SpaceX Rent a Stopgap
Anthropic's S-1 says the lab now runs its own data centers, and the SpaceX compute it rents can be cancelled on 90 days' notice from early 2027.
Anthropic filed its S-1 publicly on Monday, and the most interesting part of it has nothing to do with the share price. Buried in the compute section is a new unit called Anthropic Direct, and it means Anthropic has started running its own data centers. The filing says the first one became operational this year. It also explains, fairly plainly, why the rented capacity Anthropic has been signing all year is a bridge to get there.
That matters because the biggest bridge belongs to SpaceX. Anthropic agreed to spend up to $120.5 billion with SpaceX's AI unit through 2029, which works out to about $3.1 billion a month once all the capacity is delivered in December. Either side can walk away on 90 days' notice once the locked-in periods end in January and March 2027.
What Anthropic Direct actually is
Until now Anthropic bought compute the way most labs do, as a cloud service from Amazon, Google, Microsoft and a growing list of neoclouds (GPU-rental companies like CoreWeave and Nebius that exist to lease chips to AI labs). Anthropic Direct is the other half of what the S-1 calls a hybrid model. Anthropic leases the chips itself, puts them in halls built to its spec, and pays someone else to run the building.
The reasoning is the part I had to read twice. The S-1 says data centers "represent a smaller fraction of total compute costs" than the chips inside them, while taking much longer to build. So Anthropic signs for the building early, when it's cheap to commit, and waits on the expensive chip order until it knows what it needs. You can see why a lab would want that, because the building takes longer to finish than the chips take to ship.
The operator is Fluidstack, a private London company that builds and runs GPU halls, under what the filing calls a colocation and services agreement. Anthropic also says it has signed data center leases directly and expects to do more of them. It has gone further than that, too, writing guarantees for developers who order long-lead equipment (the transformers and switchgear that take a year or more to arrive) on its behalf. As of June 30 those guarantees topped out at $0.8 billion. It's a small number, but it means Anthropic now carries some of the risk on orders it didn't place.
Broadcom is the landlord for the chips
The chips come through Broadcom, and the dollar figure dwarfs everything else in the section. Under a five-year equipment lease signed in March, Anthropic owes about $125.2 billion in rent, payable quarterly once each batch of hardware is ready for service. That lease can't be cancelled except on default. Broadcom has also agreed to lend Anthropic up to $42 billion in convertible notes to help pay it, so Broadcom is financing a third of the rent on its own chips (Reuters reported the facility on October 1, and the public S-1 confirms it).
We covered the Broadcom contract and the SpaceX walk-away clause in our IPO odds piece two weeks ago. What's new is the sentence that ties them together. Anthropic says the flexibility from Direct lets it "backfill the short-term compute we procure during periods of high demand" with cheaper long-term capacity as its own halls come online. Read that next to the SpaceX terms and the $3.1 billion a month looks like the short-term compute it's describing.
Why renting stops making sense
The income statement explains the urgency. Anthropic booked $16.3 billion of revenue in the first half of 2026, and compute and infrastructure cost it $8.9 billion. That's 55% of revenue, down from 201% a year earlier, because revenue grew faster than the compute Anthropic had committed to in advance. At that scale, every point of margin Anthropic can take back from a cloud provider is worth hundreds of millions of dollars a year.
The timing is awkward for the rental business. Elon Musk posted on Sunday that more than 200 neoclouds face "guppy-level death" because debt markets have closed to them, and CoreWeave, Nebius and IREN all fell on Monday's open. His pitch was that SpaceX survives because it borrows at investment grade. That's true, but the S-1 shows SpaceX's biggest outside tenant planning around the day it needs less rented capacity.
The leases that last
The companies with the better paper here are the ones leasing Anthropic buildings for a decade or more. Riot Platforms, the bitcoin miner, signed a $9.1 billion lease with Anthropic at its Rockdale campus in Texas, which Riot puts at 241 MW. TeraWulf signed Anthropic to a 20-year lease at its 401 MW Kentucky campus. Hut 8 is building a 245 MW campus in Louisiana for Fluidstack and Anthropic. Those are the dedicated facilities the S-1 describes, and none of them comes with a 90-day exit.
So the chain runs like this. Broadcom books the chip lease as hardware revenue, with $125.2 billion due over five years. Riot, TeraWulf and Hut 8 book long-dated rent on the shells. GE Vernova and Vertiv make the kind of long-lead gear Anthropic is now guaranteeing orders for. The rental layer, SpaceX included, gets the demand Anthropic can't yet house itself.
I'd rather hold the 20-year lease than the 90-day one. Anthropic's S-1 says plainly which one it plans to keep paying.