Will OpenAI or Anthropic IPO first?

OpenAI has the stronger procedural position because it has already confidentially filed an S-1, which is the clearest hard signal that an IPO process is underway. That matters because, all else equal, a company that has formally entered the SEC pipeline usually has a better chance of reaching the market first than a peer still relying on reported target dates. OpenAI also appears more likely to have the organizational scale, investor pressure, and strategic incentive to move toward a listing once conditions are favorable.

Against that, the timing evidence is not nearly as decisive as the market price suggests. OpenAI has not set a public date, and recent reporting points to a possible slip into 2027, while Anthropic is being described as targeting an October debut. If Anthropic’s timing is real and OpenAI waits, the reported lead could flip quickly. In other words, the market is treating OpenAI’s early filing as close to a near-lock on first-to-list status, but the gap between filing and actual listing is large enough that execution risk remains meaningful.

My independent read is that OpenAI is favored, but only moderately, because formal process advantage tends to matter more than speculative timing chatter unless the latter is backed by stronger confirmation. The current 85% market probability looks too high given that both companies are still missing firm public dates and both may rationally delay to optimize valuation or market conditions. This is a classic case where the market may be overweighting the most concrete headline and underweighting the real possibility that Anthropic moves first if OpenAI’s timeline drifts.