Anthropic’s IPO is now official and on the public record. The company behind the Claude family of AI models publicly filed its S-1 registration statement with the U.S. Securities and Exchange Commission on Monday, October 26, 2026, and the filing was accepted at 9:00:11 a.m. Eastern. The company plans to list its Class A common stock on the Nasdaq Global Select Market under the ticker symbol ANT.

“Anthropic has filed an S-1 registration statement with the SEC related to its proposed IPO,” the company said in its announcement on Monday. Goldman Sachs and Morgan Stanley lead a syndicate of 24 underwriters. Both Anthropic and existing shareholders will sell shares, but the filing sets no share count or price range yet, and the registration has not become effective, so no shares can be sold until the SEC clears it.

The public filing confirms the headline financials that emerged from a draft prospectus reviewed by the Wall Street Journal last week, which GPTOnline covered on October 20: revenue of $16.3 billion for the six months ended June 30, 2026, against a net loss of $80.7 billion, most of it a $72.4 billion non-cash accounting charge tied to convertible financing. The filing adds new detail: an operating loss of just $693 million for the period, cash and equivalents of $112.4 billion, and $141.1 billion of capital raised to date.

Founders Keep Control

The most striking new disclosure in the public filing is how little say public shareholders will have. Anthropic is a Delaware public benefit corporation, and its structure is built to keep control with the founders and with a body charged with protecting the company’s mission.

A single Class F share, held by an LLC owned by the seven co-founders, will carry 50.1% of total voting power. A five-member Long-Term Benefit Trust will be able to elect a majority of the board through a special class of Class T shares. The company also put 5% of its fully diluted shares into a public benefit fund, and each co-founder has pledged to give 80% of personal Anthropic equity to philanthropic causes.

The filing also lays out the scale of the spending behind the growth. Anthropic has locked in binding, non-cancellable computing contracts worth $450 billion over the next seven to 10 years, including $111 billion to Google Cloud, $110 billion to Amazon Web Services and $31 billion to Microsoft, according to the Wall Street Journal’s reading of the filing. A chip-leasing deal with Google through Broadcom worth more than $160 billion pushes the total future infrastructure bill above $600 billion.

The public filing at a glance
Graphic: GPTOnline

The Risk Factors

The prospectus devotes significant attention to AI safety risks, and the language is unusually blunt for a company about to sell shares to the public. Anthropic warned that advanced models could pose catastrophic or existential risks to humanity, and that in controlled testing, models have shown behavior including attempts to resist shutdown, conceal or manipulate information, and behavior resembling blackmail.

Anthropic governance and founder control
Graphic: GPTOnline

The filing also warns that after a catastrophic AI incident, no single insurer, and potentially the insurance industry in the aggregate, may be able to cover the damage.

The filing also discloses that Anthropic paused training of its next-generation flagship model for more than a month over security concerns, delaying pre-training of a new “frontier” base model to strengthen safeguards against theft of model weights and intellectual property, according to Reuters. Anthropic warned that such pauses could delay revenue and leave it trailing competitors.

Markets React

AI-linked stocks rose on Monday after the filing, with Nvidia adding nearly 3% and Microsoft and Amazon gaining nearly 1% each, according to Reuters. CoreWeave rose 5.7% and Nebius Group 2.3%, reversing earlier losses, while the Philadelphia Semiconductor Index gained over 3%.

Investors are divided on what the debut will prove. “I’m optimistic about AI as a technology. And Anthropic is certainly exciting. But are we going to rush in and buy at the IPO? No,” Josh Stevens, chief investment officer at Cresalta Investment Management, told Reuters. Peter Andersen, founder of Andersen Capital Management, called it “a significant milestone in the development of artificial intelligence” and said the outcome “will be fairly indicative of the sentiment for continuing to support capital expenditures in the development of artificial intelligence.”

What Comes Next

Bankers are reported to be aiming for up to $100 billion in proceeds at a valuation of roughly $2 trillion, with a roadshow expected the week of November 9, though neither figure appears in the filing and Anthropic has not confirmed them. In May, the company raised $65 billion at a $965 billion valuation, and more recent reports have put the valuation under discussion closer to $1.5 trillion.

A successful listing would set the benchmark for the rest of the industry. Focus now shifts to a potential IPO from OpenAI, whose own economics remain private, and to whether public markets will pay a premium for a pure-play AI company whose founders have deliberately limited shareholders’ say.

Sources