SAN FRANCISCO: OpenAI is filing a confidential IPO prospectus with the Securities and Exchange Commission as soon as Friday, May 22, 2026, according to multiple sources. The filing is being led by Goldman Sachs and Morgan Stanley, with a public listing targeted as early as September 2026 at a valuation north of $1 trillion. If priced at that level, it would be the largest IPO in history.
The development was first reported by CNBC on May 20, with Bloomberg and Axios confirming details shortly after. OpenAI declined to comment publicly. The confidential filing format keeps the prospectus out of public view until OpenAI flips it public, typically 15 to 30 days before pricing.
When did OpenAI file for IPO and what is the target valuation?
OpenAI is filing confidentially with the SEC on or around May 22, 2026. The target valuation is above $1 trillion, with a public listing window targeted between September and November 2026. The current private valuation is $852 billion, set in March 2026 when OpenAI closed a $122 billion funding round backed by Amazon, Nvidia, SoftBank, and others. The IPO would price the company more than $150 billion above its most recent private mark.
Goldman Sachs and Morgan Stanley are the lead underwriters. A confidential filing lets OpenAI work with SEC staff on the prospectus privately, refine financials, and time the public flip for favorable market conditions. The S-1 itself stays out of public view until OpenAI chooses to release it.
How OpenAI cleared the path to going public
The IPO filing is the third major step in an 18-month sequence that started with a corporate restructuring and ended with a courtroom verdict. In October 2025, OpenAI converted its for-profit arm into a Public Benefit Corporation (OpenAI Group PBC) and rebranded the original nonprofit as the OpenAI Foundation. The restructuring eliminated the capped-profit structure that had limited investor returns to 100x their original investment. Without that cap removed, a public listing was not legally workable.
The second step was the revenue ramp. OpenAI’s annualized revenue hit $25 billion in February 2026, up from $20 billion at the end of 2025 and roughly $4 billion a year earlier. CFO Sarah Friar has guided investors toward continued enterprise growth, and Sam Altman has floated $100 billion in annualized revenue by 2027 as the next benchmark.
The third step closed on May 18, 2026, when a federal jury in the Northern District of California rejected Elon Musk’s claims against OpenAI, Sam Altman, and Greg Brockman in under two hours. Judge Yvonne Gonzalez Rogers ruled the suit was filed too late under California’s statute of limitations. That verdict removed the last major legal overhang and made the timing of this week’s filing possible.
What OpenAI’s $1 trillion IPO means for AI founders
A $1 trillion print resets the comps spreadsheet for every AI startup raising in 2026 and 2027. The most direct effect is at the foundation-model layer. Anthropic’s $900 billion valuation already priced off the same trajectory, and the two companies together capture about 89% of revenue among top AI startups. With both leaders now valued above $850 billion in private markets and OpenAI heading toward a public listing, the window for a new venture-backed foundation-model company has functionally closed.
The capped-profit restructuring carries a separate lesson. OpenAI spent more than a year converting from a nonprofit-controlled capped-profit entity into a PBC because the original structure could not support a public listing. Mission-driven structures sound elegant at incorporation. They become very expensive to unwind when the company outgrows them. Founders building on dual-class shares, PBC structures, or mission-aligned cap tables should price the cost of restructuring into the model before signing the docs, not after.
The valuation jump from $852 billion private to a $1 trillion-plus public mark also reframes how growth-stage AI startups should think about late-stage rounds. Three of the four firms that co-led Anthropic’s $30 billion round also hold OpenAI positions. The largest growth funds are no longer picking a single foundation-model winner. They are running parallel positions in both companies and underwriting application-layer rounds against the question of which company the startup benefits from. Founders raising Series B and later in AI should expect that question on every term sheet.
The trillion-dollar IPO logjam
OpenAI is not filing alone. SpaceX filed its S-1 publicly on May 20, two days before OpenAI’s confidential filing. Anthropic has signaled it is weighing a public listing as early as October 2026. If all three companies price near their reported targets in the same quarter, combined new equity supply could exceed $135 billion. There is no modern precedent for that scale.
For AI founders, the logjam matters in two ways. First, the late-2026 IPO window will absorb growth-equity capital that would otherwise rotate into private rounds. Funds that wrote $2 billion checks into Anthropic and OpenAI in 2025 and early 2026 will be allocating to the public deals through Q4. Series B and Series C raises in adjacent AI categories should be planned around that liquidity rotation, not against it.
Second, the public-market reception will set the secondary signal for every private AI valuation. Bloomberg reported that some bankers privately estimate Anthropic’s public-market valuation at $400 to $500 billion, a sharp discount to its $900 billion private mark. If OpenAI prices and trades meaningfully below its private target, every AI startup carrying a 2026 valuation will face a markdown conversation at its next round.
What to watch through the rest of 2026
Three signals will define the next six months. The first is whether OpenAI flips the confidential filing public in July or August, which would lock in the September listing window. A slip into Q4 or 2027 would suggest the SEC review or the price discovery process is hitting resistance.
The second is the revenue print between now and the listing. OpenAI’s $25 billion annualized number is the load-bearing figure in the valuation. A run-rate that stalls or declines into the prospectus update would force a price cut. A run-rate that accelerates toward Altman’s $100 billion 2027 target would harden the trillion-dollar mark.
The third is the OpenAI-Anthropic spread by year-end. The two companies that capture 89% of AI startup revenue are heading into the second half of 2026 with similar valuations, the same investor base, and different product strategies. OpenAI is the consumer-mindshare bet anchored by ChatGPT. Anthropic is the enterprise-revenue bet anchored by Fortune 10 contracts. The public market will decide which playbook deserves the premium. Founders building in AI will be planning around whatever the gap looks like by January.
