Anthropic Files Confidential IPO Papers with the SEC, Targeting a Trillion-Dollar Debut
Anthropic has submitted a confidential S-1 to the SEC, setting up a potential October 2026 IPO at a valuation above $1 trillion.
Anthropic has filed a confidential draft S-1 registration statement with the U.S. Securities and Exchange Commission, the formal first step toward an IPO. The company published a brief Rule 135 notice on its website on 1 June 2026. No share count or price has been set yet, and the offering remains subject to SEC review and market conditions, but the target window is October 2026.
If it prices at the valuation being discussed, this will be the largest tech IPO in years, and it puts Anthropic ahead of OpenAI in the race to public markets.
How we got here, quickly
The timeline is genuinely fast. In December 2025, Fortune valued Anthropic at $183 billion. By February 2026 that had risen to $380 billion. Then, just four days before the S-1 news, Anthropic closed a $65 billion Series H round at a post-money valuation of $965 billion, overtaking OpenAI’s $852 billion valuation from March.
That round was co-led by Altimeter Capital, Sequoia, Dragoneer, Greenoaks, Coatue, Capital Group, and others, with participation from Blackstone, Brookfield, Fidelity, and strategic investors including Samsung, SK Hynix, and Micron. Amazon contributed $5 billion of the $65 billion total as part of its previously committed infrastructure partnership.
A debut above $1 trillion would put Anthropic in contention for one of the largest IPOs ever recorded, behind Saudi Aramco and potentially SpaceX.
The numbers behind the valuation
Anthropic’s revenue run-rate has reportedly surpassed $47 billion, up from $9 billion at the end of 2025. That is extraordinary growth by any measure. OpenAI generated $5.7 billion in revenue in Q1 2026 alone, which is more than Anthropic for that period, but Anthropic’s trajectory has clearly caught investors’ attention.
More than 1,000 businesses are now spending over $1 million annually with Anthropic, and enterprise customers account for roughly 80% of total revenue. A significant contributor to that growth is Claude Code, the programming-focused product that crossed $2.5 billion in annualised revenue within its first year of general availability.
On profitability, Anthropic projects breaking even by 2028, two years ahead of OpenAI’s 2030 target according to the Wall Street Journal.
Why a confidential filing, and what happens next
Confidential S-1 filings are standard practice for high-profile IPOs. They allow a company to work through SEC feedback privately before anything becomes public. If Anthropic decides to proceed, it will eventually file a public S-1 containing detailed financials, risk factors, and voting structure information. Until then, the company retains flexibility to adjust its plans or pull back entirely without the scrutiny of a public document.
Rumours suggest the public offering could be sized at around $75 billion, representing roughly 5 to 10 percent of the company.
What this means for you
If you follow the markets or invest in tech: This is the IPO the AI sector has been building toward. Dan Ives of Wedbush called it “an opening of the floodgates for the IPO market, which has been relatively dormant for a few years.” If public investors embrace Anthropic’s valuation, it sets a reference point for OpenAI’s own listing and could extend the rally in AI infrastructure stocks broadly. If Anthropic, OpenAI, and SpaceX all list within months of each other, you are looking at close to $3 trillion in new market capitalisation arriving in public markets in a compressed window.
If you are an enterprise customer using Claude: A public listing means Anthropic’s financials will eventually be open to scrutiny, which generally brings more accountability and predictability. The company’s stated goal of achieving profitability by 2028 also suggests it is not solely dependent on continued fundraising to operate, which is relevant if you are making long-term procurement decisions.
If you work in AI or are watching the industry: The race to public markets matters because whoever lists first tends to benefit from investor attention before fatigue sets in. Anthropic’s confidential filing puts pressure on OpenAI to accelerate its own timeline.
The complications worth watching
Anthropic is organised as a public benefit corporation, with an internal Long-Term Benefit Trust that holds some oversight responsibility. That structure may create friction with investors focused purely on returns, and how public markets price that governance layer is genuinely unknown.
There is also a significant commercial risk on the federal side. Defence Secretary Pete Hegseth sanctioned Anthropic earlier this year under two government supply-chain laws, removing Claude from military and federal agency use. Anthropic refused to allow unsupervised deployment of its models in scenarios like weapons targeting and domestic surveillance. The company has filed suit to overturn the sanctions and estimates they could cost it billions in sales. That dispute will almost certainly feature prominently in the eventual public S-1.
On the compute side, Anthropic has been moving aggressively. It has signed agreements with Amazon for up to five gigawatts of new capacity, with Google and Broadcom for five gigawatts of TPU capacity, and with SpaceX for GPU access across its Colossus data centres. The SpaceX deal alone is reportedly valued at $1.25 billion per month through May 2029. Claude is now available on AWS, Google Cloud, and Microsoft Azure, the only frontier model with that kind of cross-cloud reach.
The October IPO window is still months away, and a lot can change. But the confidential filing is not a rumour or a plan being discussed in boardrooms. It is a formal regulatory step, and it signals that Anthropic is serious about going public this year.