A widely shared cap table reconstruction posted on X by investor and writer Sheel Mohnot has put hard numbers to OpenAI's ownership structure for the first time, estimating stakes, cost bases, and return multiples for major investors at an $852 billion post-money valuation.
The document was rebuilt from public filings and secondary-market disclosures, and frames an eventual IPO as a potential watershed comparable to the largest tech listings of the past decade.
Microsoft's position
Microsoft emerges as the largest paper winner, holding a 26.79% stake valued at $228.3 billion against roughly $13 billion of investment. That implies an unrealized gain of $215.3 billion and a 17.6x multiple, a figure consistent with Microsoft's own 10-Q filings. The reconstruction also notes that OpenAI flagged Microsoft as a business risk in investor materials circulated ahead of the anticipated listing.
SoftBank's bet
SoftBank is shown holding an 11.66% stake worth $99.3 billion on a $64.6 billion commitment. CNBC confirmed SoftBank had fully funded a $40 billion commitment, with the reconstruction suggesting the Japanese conglomerate is already sitting on more than $50 billion in unrealized gains at the current valuation.
Early backers and the Altman question
Early venture positions show eye-catching multiples on small percentage stakes. Khosla Ventures holds 0.18%, implying a 30x return; Sound Ventures implies roughly 43x; Thrive Capital's 1.98% stake implies 4.8x. Sam Altman's entry in the table is listed as TBD, consistent with public reporting that he holds no equity in the company. Altman denied reports of a pending large equity award at an all-hands meeting with staff.
The foundation's control
The OpenAI Foundation is shown holding 25.80% at zero cost basis, a stake valued at $219.8 billion that carries board appointment rights. That structure is at the centre of Elon Musk's ongoing fraud suit against the company, which is set for trial this month.
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The reconstruction makes the concentration of dollar returns visible at a moment when an IPO, expected in 2026 or 2027, would convert those paper gains into realized outcomes.
The recap
- Reconstructed OpenAI cap table leaked on X by Sheel Mohnot.
- Microsoft holds 26.79% stake estimated worth $228.3 billion.
- IPO expected 2026 or 2027 will resolve paper returns.
