Anthropic booked about $17 billion in revenue in the three months to 30 September 2026 but slipped back to a $567 million operating loss, its amended IPO prospectus shows,.

The Claude maker filed the amended Form S-1/A with the US Securities and Exchange Commission on 2 November 2026, adding third-quarter results to its 26 October prospectus. Revenue rose from $11.6 billion in the second quarter and $1.4 billion a year earlier, up 1,127% year on year.

The return to loss followed Anthropic's first operating profit, of $974 million, in the second quarter. The filing says the swing was primarily driven by about $5 billion of computing capacity bought under short-term commitments, which it says currently costs significantly more than capacity secured under multi-year deals, plus about $2 billion of non-cash charges tied to an employee donation matching programme.

Compute and infrastructure expenses rose to 58% of revenue in the quarter, from 48% in the second quarter, the filing says. Revenue for the nine months to 30 September reached $33.24 billion, up roughly 1,200% from the same period in 2025.

The filing also puts a number on future spending for the first time: about $895.4 billion in purchase and lease commitments, almost all of it for computing power and data centres, with roughly $70 billion due within a year. The biggest suppliers are Broadcom, at about $161 billion in equipment leases, Google at about $121 billion, SpaceX's AI unit at up to $120.5 billion and Amazon at about $110 billion.

Anthropic plans to list Class A shares on the Nasdaq under the ticker ANT, with the price range and share count still blank. It is preparing to begin marketing shares to investors as soon as next week, but the offering cannot be priced until the SEC declares the registration effective.