OpenAI has filed confidentially for an initial public offering, submitting a Form S-1 with the Securities and Exchange Commission on Monday. The announcement comes just over a week after Anthropic, its main competitor, filed for its own IPO on June 1st, intensifying the competition between the two leading artificial intelligence companies.
The confidential filing allows OpenAI to begin the regulatory review process while keeping financial details private until closer to the actual public offering. This approach has become standard practice among major technology firms seeking to go public, including Elon Musk's SpaceX, which is also pursuing a similar confidential filing strategy.
OpenAI's move follows Anthropic's remarkable ascent in the AI industry. Anthropic announced last week that it had raised $65 billion in funding, valuing the company at $965 billion. This valuation represents a dramatic increase from $380 billion in February and has allowed Anthropic to leapfrog OpenAI as the world's most valuable startup. The company's rapid growth has been fueled largely by the success of its Claude chatbot, particularly its advanced coding assistant products released late last year, which gained significant traction with software engineers and business clients.
Both companies are part of a larger trend of major AI players moving toward public markets. SpaceX has filed for a stock market float at a valuation of approximately $1.75 trillion while seeking $75 billion in investment. Industry analysts expect Anthropic to potentially go public as early as fall of this year, though neither company has disclosed an exact timeline.
The back-to-back confidential filings by the two most prominent AI startups reflect both the growing financial stakes in the AI race and confidence in market conditions despite broader economic uncertainty. These public debuts will establish key benchmarks for how investors value artificial intelligence companies and could help define the sector's growth prospects.
Anthropic has had a particularly active year beyond its IPO preparation. The company spent $1.6 million on lobbying efforts in the first quarter of 2026 alone, up significantly from $360,000 during the same period the previous year. The company is also engaged in a high-profile lawsuit against the Trump administration regarding the Pentagon's use of its Claude AI, after the Department of Defense designated Anthropic a "supply chain risk" and blacklisted it from military work.
Meanwhile, OpenAI CEO Sam Altman's identity verification company, Tools for Humanity, is reportedly struggling with revenue generation and planning staff layoffs, according to reports published alongside OpenAI's IPO filing announcement.
The confidential filing process gives regulators time to review financial disclosures before Anthropic's investor prospectus becomes public. As "This gives us the option to go public after the SEC completes its review," Anthropic stated, the proposed offering will ultimately depend on market conditions and other factors.