It’s official: OpenAI has confidentially filed its S-1 with the SEC. What’s been building for weeks is now reality — and it completes the largest AI IPO trio the world has ever seen.
Three giants, three filings
Within two weeks, SpaceX, Anthropic, and OpenAI have all filed their IPO paperwork. SpaceX starts trading first. Anthropic filed on June 1st. And now OpenAI. Together, the three companies represent a combined market cap of well over $2 trillion.
OpenAI is currently valued at around $852 billion. Morgan Stanley and Goldman Sachs are underwriting the offering. No specific timing has been set yet — the IPO could happen as early as Q4 2026.
Anthropic is suddenly worth more
Here’s a surprising twist: on the secondary market, Anthropic has broken through the $1 trillion mark — overtaking OpenAI. On the Forge Global platform, Anthropic trades above $1 trillion, while OpenAI sits at around $880 billion.
Who would’ve predicted a year ago that the ‘safety-focused underdog’ would surpass the first mover in valuation? Anthropic’s combination of Opus 4.8, Claude Code, Cowork, and the SpaceX compute deal seems to convince investors more than OpenAI’s consumer dominance with ChatGPT.
What the filings mean
A confidential S-1 filing is the first formal step toward going public. The SEC reviews the documents before they become public. OpenAI has emphasized there are things that are easier to do as a private company — a signal that the actual listing could still be months away.
But the direction is clear: the three most valuable AI companies in the world will soon be publicly traded. That fundamentally changes the dynamics — more transparency, more pressure, but also more capital for the next phase.
My take: This IPO trio is historic. SpaceX for compute, Anthropic for safety-first AI, OpenAI for consumer AI. The fact that Anthropic is worth more than OpenAI on secondary markets tells you something: the market isn’t just betting on the largest user base, it’s betting on the best technology. It’ll be fascinating to see how valuations shake out after the actual listings.
Sources: TechCrunch, CNBC, SiliconANGLE, CNBC