OpenAI Files Confidential IPO Paperwork at $852B Valuation — One Week After Anthropic
OpenAI confidentially submitted an S-1 to the SEC, becoming the third major AI company in the IPO pipeline after Anthropic and SpaceX. The company is valued at $852 billion and says timing is undecided — 'it may be a while.'
OpenAI confidentially filed S-1 paperwork with the SEC on Monday, joining an AI IPO pipeline that Bloomberg now values at roughly $3.6 trillion. The filing came exactly one week after Anthropic’s confidential S-1 and days before SpaceX prices its expected $1.75 trillion listing.
OpenAI announced the filing itself rather than waiting for it to surface. The reasoning was blunt: “We expect it to leak so we’re just announcing it,” the company told Fortune. On timing, OpenAI was deliberately vague — “We have not decided on timing yet; it may be a while because there are things we want to do that are likely easier as a private company.”
The numbers underneath the filing are enormous in both directions. OpenAI was valued at $852 billion post-money after its $122 billion March 2026 funding round — the largest private raise in history, which included roughly $3 billion from retail investors via banks. Secondary-market trades in April pushed the implied valuation near $880 billion. ChatGPT now reaches about 900 million weekly active users.
The spending is just as large. OpenAI projects roughly $122 billion in computing costs for 2028 alone and an $85 billion cash burn that year even with sales doubling. By its own projections, the company will not be cash-flow positive for at least four more years. That math is exactly why the public markets beckon: at this scale, private capital — even sovereign wealth and the largest funds — stops being sufficient. Goldman Sachs and Morgan Stanley are leading the preparations, and people familiar with the process say a listing could come as soon as the fourth quarter of 2026.
The competitive sequencing matters. Anthropic filed on June 1 carrying a $965 billion valuation from its latest round and a roughly $1 trillion secondary-market price, and claims it is approaching its first quarterly profit — a contrast OpenAI’s burn-heavy S-1 will eventually have to answer in public disclosures. SpaceX, with xAI folded into its orbital-compute story, is expected to reach the market first.
A confidential filing lets the SEC review financials before anything becomes public, so the substance of OpenAI’s books stays hidden for now. But the signal is unambiguous: all three of the most valuable private companies in the world decided, within the same two-week window, that the next phase of the AI capital war will be fought with public money. Whoever lists first sets the comparables for everyone else — and likely absorbs the largest pool of index-fund demand before investor appetite is tested.