SAN FRANCISCO — Artificial intelligence giant Anthropic filed papers Monday for what could be the biggest initial public offering of stock ever even as its top executive warns that advanced AI could pose an existential threat to humanity. The filing 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 US$86 billion. An Anthropic IPO would also put the company ahead of OpenAI in going public in what is expected to be a pair of blockbuster stock debuts for the rival AI labs. The filing comes weeks after CEO 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 do 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 co-founder, Daniela, by billions of dollars. The 335-page document showed Anthropic’s revenue is growing rapidly, but like many other tech companies going public, it has yet to turn a profit. The company behind the chatbot Claude reported a net loss of US$80.7 billion in the first half of 2026. That compares to a loss of US$13 billion in the same period a year earlier. Despite the losses, Anthropic, valued earlier this year at US$965 billion by private investors, is reportedly set to see that value rise to US$1.5 trillion or possibly US$2 trillion, although its final valuation has not been established. At US$1.5 trillion, Anthropic would rank among the world’s most valuable public companies, alongside Tesla. As for money raised, the offering could bring in as much as US$100 billion, according to reports, surpassing the current record set by another one of Musk’s companies, SpaceX, earlier this year. In a regulatory filing, Anthropic said it will list its stock on the Nasdaq Global Select Market under the ticker symbol “ANT.” Formed in 2021 by ex-OpenAI leaders, Anthropic is locked in a fight for dominance with that company, and the two leaders, Amodei and OpenAI CEO Sam Altman, are widely seen as bitter rivals. But they have plenty of other competitors, including Google, newer startups in the U.S. and China and Musk’s SpaceX, which has an AI business. Anthropic, OpenAI and SpaceX’s AI division have all been losing more money than they make because of the huge costs in resources in building AI, fueling concerns of a bubble. The IPO would help cover any cash shortfall as well as shower extraordinary wealth on Anthropic’s seven founders, including Amodei and his sister. Collectively they own nearly 500 million shares, though it’s unclear from the offering document how much that will represent of the company after the IPO. Dario, 43, and 39-year-old Daniela, who is Anthropic’s president, are worth US$15.5 billion each, according to Forbes, which ranks them as the 176th and 177th richest in the world. The filing also listed a host of risks for the San Francisco-based Anthropic, ranging from not being able to retain key staff, navigate regulatory roadblocks and secure enough compute power to run its AI systems. But the standout was that its AI models could “pose catastrophic or existential risks to humanity.” Calls for an AI slowdown The IPO comes as worries about AI grow inside and outside the industry and reports continue to emerge about increasingly powerful systems that solve problems beyond human capacity but could also go rogue and carry out other, more harmful tasks. In September, Amodei said the AI industry should slow its fast-moving development to give safety measures time to catch up. Without such a slowdown, Amodei warned AI could be capable of letting loose a swarm of agents that could take over the entire internet within six to 12 months. He offered a plan in a post on his website to increase checks on the industry, noting that Anthropic is already undertaking part of this on its own. As for other steps, though, he said that would require coordination across the industry and with governments around the world, including authoritarian ones. “I believe that if slowing down bought us even an extra year or two before models reach critical levels of capability, and we used that time to advance alignment, we could greatly reduce the risk that something goes seriously wrong,” Amodei wrote. Clashes with the U.S. government Anthropic has tried to set itself apart from other AI companies as the “good guys,” focusing on safety and responsible development as opposed to growing at all costs and with few guardrails. Some of this sentiment stems from the company’s dispute with the U.S. government, which broke out in February when President Donald Trump and Defense Secretary Pete Hegseth accused Anthropic of endangering national security and designated the company a supply chain risk. Anthropic sued the Pentagon over the supply chain risk designation in March for what it called an “unlawful campaign of retaliation” over its refusal to allow unrestricted military use of its technology. The legal challenge intensified an unusually public dispute over how AI can be used in warfare and mass surveillance. ChatGPT maker OpenAI made its own deal to work with the Pentagon hours after the government punished Anthropic for its stance. Anthropic also filed a separate and narrower case involving a different rule the Pentagon is using to try to declare Anthropic a supply chain risk. A California judge ruled in Anthropic’s favor in the first case and a Washington D.C. judge sided with the government in the second. Both sides are appealing the decisions. --- Barbara Ortutay and Bernard Condon, The Associated Press Condon reported from New York.
