Anthropic confidentially files draft S-1 with the SEC

Anthropic confidentially submitted a draft S-1 registration statement to the US Securities and Exchange Commission, using the Rule 135 mechanism that lets a company announce a proposed offering without it counting as an actual offer to sell securities. The company said the filing gave it “the option to go public after the SEC completes its review,” and that whether and when it did so would depend on market conditions.

The filing followed, by a few days, the close of a $65 billion Series H funding round that valued Anthropic at $965 billion post-money — co-led by Altimeter Capital, Dragoneer, Greenoaks and Sequoia Capital, with participation from Amazon, Microsoft-adjacent hyperscalers and sovereign funds including GIC and Temasek. Anthropic said run-rate revenue had crossed $47 billion earlier in May. No price range, share count or ticker was disclosed, and none of that detail becomes public during a confidential filing — the SEC review happens privately, and a company can withdraw or delay indefinitely.

The move set Anthropic ahead of OpenAI in the race toward a public listing: OpenAI, last valued near $852 billion, filed its own confidential S-1 a week later. Both companies remain loss-making at scale relative to revenue, and neither filing resolved the questions that would shape any eventual listing — governance structure, the unusual capped-profit or nonprofit-linked arrangements each company has used to raise capital, and how public markets would price businesses whose valuations already assumed continued exponential growth. The filing was a procedural first step rather than an announcement of intent to list on a fixed date; commentators noted only that a public offering had become plausible rather than confirmed.