SpaceX S-1: $2.7M/MW and a $15B Anthropic Compute Deal
A line SpaceX cut from its S-1 disclosed Colossus II built at $2.7M/MW. Paired with Anthropic's $15B run-rate, AI-capex payback prints under one month.
The line SpaceX quietly cut
SpaceX scrubbed a single line from its S-1 that effectively rewrites the bull case for its AI segment. An earlier draft of the filing — reviewed by PitchBook — disclosed that the first two Colossus II clusters were built at $2.7 million per megawatt, roughly a fourfold improvement on the ~$10M/MW industry benchmark. That number is gone from the final filing. What investors see now is the $1.25 billion-a-month Anthropic contract running through May 2029 — a $15 billion annual run-rate — without a capex ruler to measure it against.
What the math implies
At $2.7M/MW, the AI infrastructure pays itself back in under a month of Anthropic cash. Even doubling the disclosed cost, payback lands at 2.2 months. That is the kind of unit economics that keeps hyperscaler capex committees awake. The catch is what GAAP shows: AI generates just 6.7% of segment revenue ex-advertising, and the segment posted a $14 billion free-cash-flow loss in 2025. Starlink is doing the heavy lifting — 61% of revenue, effectively all of company FCF, at a 63% EBITDA margin.
Why the line came out
The likely reason for the redaction is the same reason traders should care. Taken at face value, the cost figure makes a clean cash-flow valuation hard to reconcile with the $2 trillion-area headline swirling around the deal. If you price SpaceX on visible Starlink cash plus a contracted Anthropic stream paying back capex inside one month, you get a different number than the one the AI-conglomerate framing produces. The 300-page S-1 leans hard on the AI label — 47% of segment-specific language — even though the dollars still flow from connectivity.
The trader read
Three things matter into pricing. First, Anthropic cash is contracted through 2029 — it underwrites the IPO floor regardless of how the segment mix evolves. Second, Nvidia stays on the right side of this story: a 4x capex advantage on Colossus II rationalizes more Blackwell orders, not fewer. Third, the halo trade runs through Tesla and anything Musk-adjacent, while AMZN and MSFT now have to price an Anthropic competitor sitting on compute they cannot easily match.
The deleted line is not a smoking gun — it's an undersell. The number that came out of the filing was the bullish one. For desks running the IPO book, the cleaner trade is to model the contracted cash and treat the AI-narrative premium as optional, not load-bearing.