Reuters got hold of a document Anthropic never meant anyone outside a banker’s office to read.
The headlines all led with the loss. Almost $42B for 2025. That number is scarier than it is true. $34B of it is a paper revaluation of older financing instruments, not cash that left the building. The number that actually matters sits further down the document, and it’s not the one anyone led with.
The Loss Isn’t the Story
Strip out the accounting noise and the operating picture is almost ordinary, by 2026 AI standards. Revenue grew 12x to $4.6B. Operating loss topped $8B, with $7.3B of that going straight into compute and infrastructure.
For comparison, OpenAI’s own 2025 operating loss, by an independently verified estimate, came in around $20.9B. Anthropic isn’t the outlier here. Every frontier lab is spending like this right now.
The Real Number
$518 billion. That’s what Anthropic has committed to spend over the next 7 to 10 years on cloud, chips, and data centers, and roughly 80% of it is non-cancelable or payable regardless of how much Anthropic actually uses.
The breakdown is specific. $111.1B to Google, running through July 2033. $110B to Amazon, through April 2036. $31.4B to Microsoft, through May 2033. On top of that, roughly $161.2B in Broadcom-related equipment commitments.
Spread evenly, that’s $50 to $75B a year, regardless of demand. Revenue needs to grow by another 10x just to cover the hardware bill that’s already been signed.
The Other Half of the Prospectus
The second half is where the risk sits. Two unnamed customers accounted for 24% of 2025 revenue between them. Many of Anthropic’s largest accounts aren’t locked into long-term contracts at all.
Costs are fixed for a decade. Revenue isn’t guaranteed for a single year. No corporation signs a ten-year contract for tokens, the way they might for office space or a cloud migration. Meanwhile open-source models keep getting cheaper, and Amazon and Google are simultaneously Anthropic’s compute suppliers, its investors, and its competitors.
This Isn’t a Software Company Anymore
Anthropic’s economics now read like an airline’s, or a factory’s. Enormous fixed costs, and one job: fill the capacity.
If demand shows up on schedule, operating leverage makes the margin look fantastic. If it’s late by even a couple of years, the data centers sit empty, and the bill comes due anyway.
I keep coming back to fiber optic cable in 2000. The cable got laid years ahead of the traffic it was built for. The traffic did eventually arrive, bigger than anyone had forecast. The companies that built ahead of it mostly went bankrupt anyway, Global Crossing among them. The technology was right. The economics of the specific companies that bet on it weren’t.
Why the IPO Is Actually Happening
Three weeks ago I wrote about the early signs of a bubble deflating. One of them: a lab that can’t close its next private round.
This prospectus explains why Anthropic’s IPO is close to unavoidable. No private market can absorb a $518B commitment. Obligations this size only get financed with public capital and public debt. The IPO is really the next funding round moving to the stock exchange, because the private round got too large to exist anywhere else, not Anthropic going public for its own sake.
The debt sitting behind data center construction right now, from Oracle to CoreWeave, is secured by exactly this kind of contract: someone’s non-cancelable obligation to pay. The entire chain rests on two or three labs being able to grow another 10x. Anthropic’s prospectus is the clearest look yet at what that actually requires.
What This Says About the Safety Debate
This number also answers a question I’d set aside until now. My own read, for what it’s worth, is that Anthropic is currently ahead of OpenAI, a new domain seems to open up every month where Claude beats very capable people at something. Calls for the lab to slow down already sounded strange against that backdrop.
The prospectus closes the question a different way. A company carrying 80% non-cancelable obligations cannot afford to slow down. It has to grow 10x or it has no way to pay for the hardware it already signed for. Arguing about anyone’s sincerity on safety stops being useful once you can just look at the incentives directly. $518B only pays off if a token never becomes a commodity, and any policy that raises the barrier for open-source or Chinese labs protects exactly that balance. It won’t slow down Google or OpenAI, they have more capital to absorb the wait.
What I’d Actually Watch
Whether Anthropic pulls this off, I don’t know. The pace of revenue growth favors them. The contract structure doesn’t. Press coverage has floated an IPO valuation near $2T.
I’d ignore the valuation headline and watch two numbers instead, in every filing from here forward: whether the two-customer revenue concentration keeps shrinking, and whether the share of revenue locked into multi-year contracts keeps growing. Those two numbers will say more than any single quarter’s growth rate.
Buying Anthropic stock here means buying a stake in a chain of data centers and a bet that someone fills them in time. It’s not a stake in an 80%-margin software business, whatever the pitch deck says.