Anthropic files for potentially the biggest IPO ever as CEO warns of risk to humanity from AI

SAN FRANCISCO (AP) — Anthropic, a major artificial intelligence company, filed papers on Monday for what could be the biggest stock market launch ever. At the same time, its top leader warns that advanced AI could pose an existential threat to humanity, meaning it could put human existence at risk.

The filing prepares the San Francisco company to begin trading its shares on Wall Street next month. Its launch could be bigger than SpaceX’s stock market launch in June, which raised a record $86 billion. Anthropic could also go public before OpenAI. The two rival AI companies are expected to have two very large stock market launches.

Selling shares to the public could give Anthropic a huge amount of money to grow faster. It is not yet clear how much money the company will raise, what the company will be worth or how much each share will cost. Even lower estimates would make the five-year-old startup one of the world’s most valuable companies. The sale could also increase the wealth of CEO Dario Amodei and his sister and co-founder, Daniela, by billions of dollars.

A 335-page document showed that Anthropic’s revenue is growing quickly. It earned more than $16 billion in the first half of the year, 14 times what it earned during the same period last year. But, like many technology companies preparing to sell shares to the public, the company behind the Claude chatbot is still losing money overall.

Private investors valued Anthropic at $965 billion earlier this year. Reports say its value could rise to $1.5 trillion or even $2 trillion, although its final value has not been decided. If it is worth $1.5 trillion, Anthropic would rank among the world’s most valuable publicly traded companies, alongside Tesla.

Reports say the stock sale could raise as much as $100 billion, beating the record set by SpaceX.

In a filing with regulators, Anthropic said it plans to list its shares on the Nasdaq Global Select Market under the stock symbol "ANT."

The company plans to enter the stock market during an uncertain time

Anthropic said in its filing that it could use some of the money to buy other companies and technology. It could also invest in the equipment and systems it needs to grow and compete with rivals.

Former leaders of OpenAI started Anthropic in 2021. The company is locked in a fight with OpenAI to lead the AI industry. Dario Amodei and OpenAI CEO Sam Altman are widely seen as bitter rivals.

But both companies face many other competitors, including Google, newer startups in the United States and China, and SpaceX, which also has an AI business. Anthropic, OpenAI and SpaceX’s AI division have all been spending more money than they earn because building AI requires huge amounts of resources. This has raised fears that the AI market could be in a bubble, with company values growing beyond what their businesses can support.

The need for money may explain why Anthropic wants to sell shares this year instead of waiting until next year, as OpenAI plans to do. Another concern is that demand for AI stocks could fall sharply or even collapse. Investors are worried about how much money AI companies need, and several technology companies have recently dropped plans to sell shares to the public.

The stock sale would also make Anthropic’s seven founders extremely wealthy, including Dario Amodei and his sister. The filing did not directly state how much of the company each founder owns. But other figures in the document suggest that each founder will own 1.4% of the company. If Anthropic goes public at the highest expected value, each founder’s stake could be worth as much as $28 billion.

Many risks, but a huge possible payoff for the founders

Forbes estimates that Dario Amodei, 43, and his 39-year-old sister Daniela, Anthropic’s president, are each worth $15.5 billion. The magazine ranks them as the 176th- and 177th-richest people in the world.

Anthropic reported a net loss of $80.7 billion in the first half of 2026. However, this figure included a one-time $72.4 billion accounting charge related to financing agreements, according to the filing. During the same period a year earlier, Anthropic lost $13 billion.

The document includes unusual rules that reflect concerns about AI’s dangers. One rule gives Dario and Daniela Amodei and the company’s five other co-founders 50.1% of the voting power held by shareholders through a special type of share. Anthropic has also chosen independent members for a group called the Long-Term Benefit Trust. These members have no financial interest in the company and have the power to appoint directors. The trust is meant to help ensure that Anthropic does not put making money ahead of public safety.

Another unusual part of the filing is its long list of "risk factors." Every public company must explain the risks it faces, but Anthropic’s list is nearly 100 pages long and includes some striking warnings.

The risks include everyday business problems, such as being unable to keep important employees or facing delays caused by regulations. They also include terrifying possibilities. The document warns that people with harmful intentions could use AI models to make chemical weapons. It also warns that authoritarian leaders could use AI to control their citizens, and that Anthropic’s AI systems could act outside human control and "pose catastrophic or existential risks to humanity."

Calls to slow down AI development

Anthropic and other leading AI companies have talked about how the technology could help cure diseases and grow the economy. But AI could also greatly change the job market by reducing the need for human workers.

A series of hacking incidents involving AI agents that acted without permission has also increased fears that AI could escape human control and carry out dangerous tasks that threaten lives.

In September, Amodei said the AI industry should slow down its rapid development so that safety protections have time to catch up. He warned that without a slowdown, AI could soon create large groups of agents that could take over the entire internet within six to 12 months.

Amodei shared a plan in a post on his website to increase checks on the AI industry. He said Anthropic is already doing some of this work itself. But other steps would require companies across the industry to work together, along with governments around the world, including governments led by authoritarian rulers.

Disagreements with the U.S. government

Anthropic has tried to stand apart from other AI companies by presenting itself as a company that puts safety and responsible development first, rather than trying to grow at any cost. Some of this approach comes from its dispute with the U.S. government. The dispute began in February, when President Donald Trump and Defense Secretary Pete Hegseth accused Anthropic of putting national security at risk and labeled it a supply chain risk.

In March, Anthropic sued the Pentagon over that label. The company called the government’s actions an "unlawful campaign of retaliation" because Anthropic had refused to allow unrestricted military use of its technology. The lawsuit made a rare public dispute even more intense over how AI should be used in war and for watching large numbers of people.

Hours after the government punished Anthropic for its position, OpenAI, the company behind ChatGPT, reached its own agreement to work with the Pentagon. Anthropic also filed a separate, narrower lawsuit over another rule the Pentagon is using to try to label the company a supply chain risk.

A California judge ruled in Anthropic’s favor in the first case. In the second case, a judge in Washington, D.C., ruled in favor of the government. Both sides are appealing the decisions.

Bernard Condon reported from New York.