Anthropic, the artificial intelligence company behind the Claude AI models, has filed its prospectus for an initial public offering in what could become the largest stock market debut in history. The company filed a 335-page registration statement on Monday, and it plans to list on the Nasdaq Global Select Market under the ticker symbol ANT.
The filing did not set a share count or a price range. Both the company and existing shareholders will sell shares, and the company is expected to begin trading in mid-November.
If the debut lives up to the reports around it, it could eclipse the record set by SpaceX, which raised more than $86 billion in its June IPO. Anthropic would then stand as the biggest listing ever, ahead of an AI rival that went public only a few months earlier.
The numbers in the filing
The prospectus gives the first detailed look at the finances of the company. Revenue reached $16.29 billion in the first half of 2026, up from $1.16 billion in the same period a year earlier.
The growth has been rapid. Annual revenue grew from $41 million in 2023 to $386 million in 2024 and $4.59 billion in 2025. Revenue in the second quarter of 2026 alone was $11.56 billion, and the company reported its first quarterly operating profit of $974 million.
Reuters reported that revenue rose further in the third quarter, up 45% to $16.8 billion compared with the second quarter.
But the filing also shows a very large net loss. Anthropic recorded a net loss of $80.7 billion in the first half of 2026. Most of it, $72.4 billion, came from changes in the fair value of convertible notes and other financial instruments as the company’s valuation rose, rather than from cash spending.
The operating loss for the period was $693 million, while operating cash flow turned positive at $3.93 billion. Cash and short-term investments totalled $131.7 billion as of 30 June.
What the market expects
The filing does not say how much money Anthropic intends to raise. Reports have put the figure at as much as $100 billion, and backers hope for a valuation of up to $2 trillion.
Other investors have weighed a figure closer to $1.5 trillion, according to Reuters. Even at that level, Anthropic would rank among the most valuable companies in the world.
Private investors had valued the company at $965 billion earlier in 2026. The gap between that figure and the reported hopes for the listing shows how fast expectations have moved.
Goldman Sachs and Morgan Stanley are named first among 24 underwriters for the offering. The size of the bank group reflects the scale of the deal and the demand that Wall Street expects.
Anthropic was founded in 2021 by seven former OpenAI employees. The company has grown from a small research lab into one of the leading developers of AI models in only five years.
The safety warning
The filing also carries a warning from the company’s chief executive, Dario Amodei, about the risks of advanced AI to humanity. It is a striking note to include in a document meant to sell shares to the public.
Amodei had already asked the industry in September to slow down AI development for safety reasons. He framed it as a request for care about the pace of development, not as a call to stop building AI altogether.
The prospectus itself warns that the company’s success depends in large part on its ability to keep developing the most advanced and capable AI models, and that any failure to do so could harm the business.
What happens next
The filing moves the IPO from rumour to a disclosed process, but several questions remain open. The company has not set a price range, a share count or a final trading date.
Trading is expected to begin in mid-November, and the next steps will be watched closely by investors, rivals and regulators. OpenAI, the maker of ChatGPT, is expected to go public sometime in 2027, so Anthropic’s debut will set an early marker for how the market values the leading AI companies.
For now, the filing tells two stories at once. One is of a company growing faster than almost any in history. The other is of a company that is still losing money on paper, even as its cash flow turns positive. Which story investors believe will decide whether this becomes the biggest IPO ever.
