Artificial intelligence giant Anthropic has filed papers for what could be the biggest ever initial public offering (IPO) of stock, even as its top executive warns that advanced AI could pose an existential threat to humanity.
The filing on Monday sets up the San Francisco company for a Wall Street debut next month, potentially eclipsing the SpaceX initial public offering in June that raised a record $86bn.
The filing comes weeks after chief executive and cofounder Dario Amodei argued in an essay for slowing the development of the most advanced AI models. An IPO could provide Anthropic with enormous resources to accelerate its expansion. The amount the company ultimately raises remains uncertain, as does its final valuation and offering price. But even at lower estimates, it would turn the five-year-old startup into one of the world’s most valuable companies and potentially boost the wealth of Amodei and his sister and cofounder, Daniela, by billions of dollars.
The prospectus highlights the AI company’s rapid growth over the past year, fuelled by Big Tech’s breakneck spending that has driven a rally in AI stocks, while raising concerns about lofty valuations and rising debt.
The company also flagged growing risks from AI technology, underscoring concerns over its potential to cause harm, which had led Amodei to call for a slowdown in development of advanced models.
Anthropic’s net loss in the first half of 2026 widened sharply to $80.7bn , largely due to a rise in the fair value of bonds convertible into the company’s shares. Revenue in the period was about $16.3bn.
The company’s revenue grew a staggering 1,368 percent in the three months ended June 30 from a year ago, but warned in the prospectus that the revenue growth rate could decline over time and fluctuate occasionally.
The IPO, which is anticipated to be before Thanksgiving in the US, late next month, is expected to establish Anthropic, the AI lab behind the viral Claude models, as a benchmark for how Wall Street values leading AI companies, including rival OpenAI.
The IPO push comes despite a once-busy autumn listing calendar thinning out as choppy markets prompt companies to delay their offerings. Analysts said that would give Anthropic access to a deep pool of capital to fund its costly AI ambitions.
Growing investor unease with the debt-fuelled AI investment boom has led to a global selloff in AI and tech stocks, as they start to doubt whether the trillions spent on data centres, chips and computing capacity will generate fast returns to support lofty valuations. Higher borrowing costs and rising bond yields have added to their caution.
However, tech companies are still hungry for cash. Meta is aiming to raise up to $95bn in its largest-ever equity fundraising, while SpaceX has inked a $40bn deal with Apollo to lease AI chips and server hardware.
Some current and prospective investors are valuing Anthropic at about $1.5 trillion, down from roughly $2 trillion a week ago, after the AI startup disclosed some financial details at a recent investor event, Reuters reported.
The prospectus also details the risks posed by increasingly powerful AI, from potential misuse and security threats to concerns that advanced systems could produce outputs that “could be interpreted as coercive, deceptive, or manipulative”.
“Anthropic’s IPO will establish a benchmark for valuing leading AI labs, influencing both upcoming listings and confidence in the companies funding the AI infrastructure build-out,” IPOX research associate Lukas Muehlbauer said.
“Its success would not necessarily benefit every AI business equally,” he added.
Anthropic said that more than half of Fortune 500 companies and over 30 percent of Global 2000 firms were customers generating at least $100,000 each in revenue for the company over the 12 months ended September 30.
The IPO comes as Anthropic’s own research raises concerns about advanced AI systems, which in controlled tests have shown behaviours including code sabotage, fraud assistance and information manipulation.
The findings have fuelled concerns about how companies can keep powerful AI systems under control as they race to deploy them commercially.
The prospectus also highlighted risks associated with its AI models, which it said could exhibit “self-preserving behaviours”, including behaviour “resembling blackmail”.
“Our increasing use of AI systems to accelerate our own research and development may cause the capabilities of our models to advance more rapidly than our ability to develop, validate and implement corresponding safety, alignment and security measures,” it said.
The company said it relies on a limited number of cloud service providers, such as Amazon, Google and Microsoft and suppliers such as Broadcom for compute and critical parts of its infrastructure. These relationships can create “dependencies and potential vulnerabilities”, it said.
Anthropic will trade on the Nasdaq after the IPO closes under the ticker symbol “ANT”.
The filing did not reveal the terms of its offering, including the number of shares it plans to sell and the proposed price range.
Anthropic, founded in 2021 by a team of researchers, was valued at $965bn in May in a funding round that drew some of the biggest names in Silicon Valley and Wall Street.
Amazon and Google were among Anthropic’s early strategic partners, investing billions of dollars in the startup while providing the cloud infrastructure needed to train and deploy Claude models.
“We believe this abundance of AI will rapidly transform every sector of the global economy in ways greater than the impact of industrialisation, electricity, semiconductors and the internet,” the prospectus said.
The company said it expects compute and infrastructure expenses to increase in absolute dollars and remain its largest operating expense for the foreseeable future.
Goldman Sachs and Morgan Stanley were named as the lead banks for the IPO alongside 20 others as underwriters. Morgan Stanley will act as a stabilisation agent, overseeing the stock’s early trading.
The roles mark another major win for Goldman and Morgan Stanley as they also led SpaceX’s IPO.
