Anthropic files for IPO at a $965B valuation — and just raised $65B to get there

Event type: Funding round + IPO filing Date window: May 28 – June 2, 2026

Anthropic is heading to public markets. On June 2, the company confidentially submitted a draft S-1 registration statement to the U.S. Securities and Exchange Commission for a proposed IPO of common stock. The filing follows its most recent fundraise by just five days — and the numbers are hard to ignore.

On May 28, Anthropic closed a $65B Series H at a $965 billion post-money valuation, led by Altimeter Capital, Sequoia Capital, Greenoaks, and Dragoneer. The round added Micron, Samsung, and SK hynix as strategic infrastructure partners, and includes $15B of previously committed hyperscaler investment (Amazon alone contributes $5B). By Anthropic's own count, its annualized run-rate revenue crossed $47 billion earlier in May.

The company says it is the first frontier model available on all three major cloud platforms: AWS (primary training partner), Google Cloud, and Microsoft Azure.

What the IPO filing means right now: Submitting a confidential S-1 gives Anthropic optionality — it can go public after the SEC completes its review, but the timing and share count remain undecided. The company explicitly notes this is "not an offer to sell securities." Whether markets cooperate with a near-trillion-dollar debut is a separate question the S-1 will eventually have to answer publicly.

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