Anthropic Files Confidential S-1, Joins SpaceX and OpenAI IPO Race

Anthropic confirmed it confidentially submitted a draft registration statement on Form S-1 to the U.S. Securities and Exchange Commission on June 1, 2026, for a proposed initial public offering of its common stock. The filing, made under Rule 135 of the Securities Act, gives the company the option to pursue an IPO once the SEC completes its review. Anthropic noted the number of shares and the offering price have not been determined and that any offering will depend on market conditions and other factors.

The confidential S-1 follows a Series H funding round announced May 28 in which Anthropic raised $65 billion at a $965 billion post-money valuation. Anthropic reported an annualized revenue run-rate above $47 billion, driven by enterprise adoption of its Claude models for coding and automated workflows. The company also cited partnerships with Amazon and Google and said it has secured large GPU commitments to support compute capacity.

Anthropic’s filing places it alongside SpaceX and OpenAI as major private companies moving toward public markets. SpaceX filed a public S-1 on May 20 after a confidential submission in April and is targeting a June 12 Nasdaq listing under the ticker SPCX, with an expected valuation range of $1.75 trillion to $1.8 trillion and a potential raise of up to $75 billion. OpenAI confidentially filed in late May and is aiming for a September public debut at valuations above $1 trillion.

Combined, the three firms represent roughly $3 trillion in potential market value. SpaceX’s filings referenced GPU costs on the order of $1.25 billion per month.

Analysts have identified revenue growth, margins and governance disclosures as key items to watch as the companies proceed through SEC review and prepare public filings. SpaceX’s roadshow is expected to begin imminently with pricing possible this week. Anthropic and OpenAI are likely to continue through SEC feedback before filing public S-1s and scheduling investor roadshows later in 2026.

Anthropic wrote on X: “Pending completion of SEC review, this gives us the option to pursue an initial public offering.” The company also posted on X: “We’ve raised $65 billion in Series H funding at a $965 billion post-money valuation… This investment will help us advance our research and expand our capacity to meet growing demand for Claude.”