Anthropic Is Going Public: Of Its $23.3 Billion Loss, $21.9 Billion Is on Paper

Anthropic's IPO materials are already online, under ticker $ANT. Pricing is expected on November 18, with trading beginning on November 19. Greg Isenberg listed 16 observations in a tweet. First, look at the point most likely to be distorted by headlines: Q3 net loss was $23.3 billion, of which $21.9 billion came from fair value changes in convertible notes and other financial instruments, a non-cash accounting loss. The money was not burned at that rate.

Q3 revenue was $17 billion, up more than 12x year over year. Nine-month revenue was $33.2 billion; full-year 2025 was $4.585 billion. Customers paying over $100,000 grew from more than 950 a year earlier to more than 11,900; those paying over $1 million grew to more than 1,900; those paying over $10 million reached about 250. TTM revenue per head exceeded $6.6 million, with about 5,300 employees.

But the operating margin is -3%, while the adjusted operating margin is 15%. Look at both sets of numbers together, not just adjusted.

Greg is more focused on existing-customer spend being about 9x. The corresponding metric in the prospectus is Net Revenue Retention of about 900%. Existing customers spending more looks more like agents running all day, with new seats only part of it. This says more than customer-count growth that Claude has entered workflows.

Q3 compute and infrastructure was $9.863 billion, more than half of revenue. Of that, $5 billion was short-term contracts, priced higher per unit than multi-year contracts. Total long-term commitments were $900.9 billion, with $70.7 billion due in the next 12 months. Demand is running ahead of supply plans; short-term compute is a patch. The patch is expensive and will also pressure gross margin. Some online commenters linked this to Claude Code limits; the prospectus does not establish direct causation, but the compute constraint is obvious.

5,300 people, quarterly revenue of $17 billion, TTM per head of $6.6 million. That number stands out among software companies. The prospectus says 90% of codebase contributions in September were written by Claude, and code volume per engineer was 45x that of 2024. High revenue per head also means a lean organization; it relies on model and compute leverage, and slower hiring makes the numbers look better. Some users said $6.6 million per head only holds if hiring is slow and the compute bill already eats half of revenue. That caveat is valid.

Anthropic is a PBC; the Long-Term Benefit Trust (LTBT) elects a majority of directors through Class T stock, and the Founder LLC gets 50.1% voting power through Class F stock. Ordinary shareholders buy Class A shares, which have economic rights but weak control. Some users asked in replies who really runs the company after IPO, the safety trust or shareholders. The prospectus answer is closer to: founders, trust, and shareholders split power, and shareholders can hardly change direction alone.

The founder letter says, never let your company be worth a dollar more than it is actually worth. That line is quite a contrast in an IPO roadshow. Pricing day will test it. Greg said it was an expression he had not seen in an IPO pitch.

Robinhood, SoFi, Schwab, Fidelity, and E*TRADE can submit indications of interest. The roadshow video has 11 chapters public. This is retail-friendly and draws more attention.

First-day moves are sentiment. Later, watch two numbers: whether the 9x existing-customer spend can continue, and whether the $5 billion short-term compute can be replaced by long-term contracts. The former determines the revenue curve; the latter determines the profit curve. The $23.3 billion loss can be explained; the $900.9 billion commitment cannot be explained away.

Sources: Greg Isenberg's tweet, Anthropic IPO page, SEC S-1/A.