San Francisco, June 2, 2026, 05:02 PDT
Anthropic quietly filed a draft S-1 with the Securities and Exchange Commission on Monday, putting it ahead of OpenAI in the race toward a U.S. stock-market debut. The proposed IPO would involve its common stock, but the filing left out the number of shares and any price details. Whether the offering actually happens, Anthropic said, will come down to market conditions.
The shift pushes Anthropic in front of OpenAI, flipping expectations for which AI startup would file first. On Monday, Reuters said Anthropic’s confidential IPO filing put it a step ahead of the ChatGPT developer, which had been working toward its own U.S. listing in the near future.
This one’s dropping into an already crowded field. SpaceX is eyeing a massive IPO, Anthropic just put in its paperwork, and OpenAI keeps flirting with a debut—leaving fund managers to puzzle over just how much fresh AI equity they can realistically take on right now. On Tuesday, Reuters markets columnist Mike Dolan pressed the bigger point: is there truly enough demand for “all this new equity at these sky-high valuations”? Reuters
A confidential S-1 is basically an early, nonpublic version of the key U.S. IPO filing, submitted for SEC staff to vet before it hits the public eye. Under SEC rules, if a company opts for this private review route, it’s required to release the registration and any previous drafts at least 15 days ahead of a roadshow—or, if there’s no roadshow, before the effective date they’re aiming for.
On May 20, Forbes suggested OpenAI’s upcoming filing could set up a showdown with Elon Musk’s SpaceX, pointing to a Wall Street Journal report putting OpenAI’s IPO timeline in September. That same day, Reuters said OpenAI was lining up a confidential filing, tapping Goldman Sachs and Morgan Stanley, and considering a September listing, according to sources.
OpenAI has more than enough heft to pull in the spotlight. On March 31, the company reported wrapping a $122 billion funding round, pushing its post-money valuation to $852 billion. Monthly revenue? $2 billion. Weekly active ChatGPT users now top 900 million.
Valuation figures at Anthropic keep getting bigger. The Claude developer disclosed last week it pulled in $65 billion through Series H, setting its post-money valuation at $965 billion. Run-rate revenue, too, passed $47 billion earlier in May. CFO Krishna Rao said the fresh capital will go toward handling “historic demand” and pushing Claude further into enterprise settings. Anthropic
Sam Altman, CEO of OpenAI, shrugged off any talk of a race following Anthropic’s filing. “Going public is a financing event,” he said to CNBC’s David Faber on Monday, making it clear that OpenAI isn’t worried about timing. For Altman, the real battle centers on who can deliver the strongest technology and business. Business Insider
Some external analysts aren’t ready to dismiss timing as a factor. Patrick Corrigan, law professor at Notre Dame who focuses on IPOs, described Anthropic’s quick action as “a little bit surprising” in comments to the Associated Press. He thinks investors will weigh both companies side by side, so Anthropic could benefit from a “first movers’ advantage.” Wedbush Securities’ Dan Ives took it a step further, labeling the move as an “opening of the floodgates” for a sector that’s seen little action for years. AP News
SpaceX is the third major player casting a shadow over the market right now. According to Reuters, the rocket and satellite firm is reportedly lining up a record $75 billion raise, aiming for a valuation near $1.75 trillion. A Nasdaq debut could happen as soon as June 12, pushing yet another Musk-affiliated company into the same capital-raising territory that OpenAI and Anthropic are eyeing.
Still, which company files first might not end up mattering. Neither Anthropic nor OpenAI has published key documents for public investors — Anthropic’s audited numbers are missing, OpenAI’s prospectus hasn’t landed. Investors are left guessing about both firms’ heavy spending on computing, salaries, and AI training. Last month, Reuters Breakingviews pointed out OpenAI isn’t profitable yet, and said investors will have to decide if the company can reach the black fast enough to warrant its current price tag.
At this point, Anthropic is the first out of the gate with a formal move. OpenAI’s ChatGPT brand still looms larger with consumers, but the IPO narrative has swerved—from talk of topping SpaceX, to whether OpenAI can actually set the pace for AI listings before Anthropic jumps in.
