Markets JUN 17, 2026

Anthropic Files Confidential S-1 at $965B, Beating OpenAI to the IPO Window

The Claude maker submitted draft paperwork to the SEC on Monday, one week after a $65B Series H. OpenAI followed seven days later.

BY HENLEY MARRAST · MARKETS DESK

Anthropic PBC filed a confidential draft S-1 with the Securities and Exchange Commission on June 1, disclosing the move in a company blog post that framed the filing as procedural: it “gives us the option to go public after the SEC completes its review.” Seven days later, OpenAI filed its own confidential S-1, accompanied by a Monday post conceding “We have not decided on timing yet; it may be a while.” The sequencing is the story.

A week earlier, Anthropic closed a $65 billion Series H at a $965 billion post-money valuation, co-led by Altimeter, Dragoneer, Greenoaks, Sequoia, Capital Group, Coatue, and D1 Capital Partners. The round arrived alongside Bloomberg and CNBC reporting that Anthropic’s annualized run rate reached $47 billion in May, up from $10 billion in annual revenue the prior year, and that the company has told investors it’s close to its first quarterly profit.

OpenAI’s numbers are larger in absolute terms and softer at the margin. Its March round of $122 billion, described by TechCrunch as the largest funding round in Silicon Valley history, set a $852 billion post-money valuation, with roughly $3 billion sourced from retail investors through bank channels. The Wall Street Journal has since reported OpenAI missed its own revenue targets, and that CFO Sarah Friar has raised internal concerns about supporting the company’s data-center spending.

Secondary markets have already priced the divergence. On Forge Global, Anthropic trades at a $1 trillion implied valuation, up 123% year-to-date. OpenAI sat near $880 billion in April, up 11.3% over the same window. Public-market investors who were locked out of the Series H rounds are voting with whatever liquidity they can find.

The compute economics complicate the picture. SpaceX’s own prospectus, disclosed May 20 after a confidential April 1 filing and targeting a $1.75 to $2 trillion IPO valuation, revealed that Anthropic will pay $1.25 billion per month through May 2029 for capacity at Colossus 1 in Memphis. That’s a $15 billion annual line item against a $47 billion run rate, embedded in another company’s S-1 before Anthropic’s own becomes public.

Three of the most consequential private companies of the decade are now in the SEC queue at once. The order in which they filed will be read as a ranking.

Sources

About the author

Henley Marrast

MARKETS DESK

Henley Marrast covers AI-equity flow, accelerator demand, and earnings prints for AI Sheet Report. She leads coverage of the public AI complex from the New York markets desk, with a focus on the daily tape and quarterly results. She has been writing about technology markets for several years.