OpenAI Cap Table Leak Reveals Microsoft’s 17x Windfall While Sam Altman Holds Zero Equity

Key Takeaways

• Microsoft’s approximately $13B investment in OpenAI now stands at roughly $228B — delivering a 17x multiple
• SoftBank deployed $64.6B and has unrealized gains exceeding $50B, with holdings valued at approximately $99.3B
• OpenAI CEO Sam Altman maintains no ownership position in the artificial intelligence company
• The nonprofit OpenAI Foundation retains 25.8% ownership acquired at no cost — while maintaining complete board control
• Nvidia’s position shows a slight loss, holding $29.6B in value against a $30.1B investment

An ownership breakdown detailing OpenAI’s shareholder structure surfaced online in early April, sparking widespread discussion about the distribution of value within the AI giant. Investor Sheel Mohnot shared the document on X, which appears compiled from publicly available filings and secondary market transactions. The data reflects OpenAI’s current $852 billion post-money valuation after completing a $122 billion capital raise.

The spreadsheet details each major investor’s ownership percentage, capital deployed, and return multiplier. This information provides unprecedented transparency into the financial structure of one of tech’s most valuable private companies ahead of its anticipated public offering.

Microsoft emerges as the dominant financial beneficiary according to the leaked data. The tech giant deployed approximately $13 billion through multiple funding rounds — beginning with a $1 billion investment in 2019, followed by a massive $10 billion injection in January 2023, plus an additional $2 billion during 2024. The company’s 26.79% ownership stake carries an estimated value of $228.3 billion, representing approximately a 17.6x return multiple. This combination of scale and returns is unmatched among OpenAI’s investor base.

Microsoft’s quarterly SEC filings verify the $13 billion total investment amount. OpenAI recently identified Microsoft as a material business dependency in investor disclosures, referencing revenue-sharing agreements and exclusive cloud infrastructure commitments.

SoftBank stands as the largest capital contributor beyond Microsoft, having pledged $64.6 billion to OpenAI. The Japanese conglomerate’s 11.66% ownership position is currently valued at approximately $99.3 billion. This represents unrealized gains surpassing $50 billion on the investment. CNBC reporting verified that SoftBank completed funding its $40 billion commitment by December 2025, utilizing a $40 billion bridge financing facility arranged by JPMorgan and Goldman Sachs.

Original Backers See Extraordinary Multiples

First movers in OpenAI’s funding history achieved the most impressive return multipliers, despite smaller absolute dollar amounts. Khosla Ventures deployed roughly $50 million during 2019, with that position now valued at approximately $1.5 billion — representing a 30x gain. Sound Ventures, the investment firm co-founded by entertainer Ashton Kutcher, committed between $20–30 million and currently holds about $1.3 billion in value, translating to a 43x multiple. Thrive Capital invested $3.5 billion and maintains a 1.98% stake currently worth $16.9 billion.

Nvidia represents the sole investor showing negative returns. The chipmaker holds 3.47% of OpenAI with a current valuation of $29.6 billion, compared to an initial cost basis of $30.1 billion. Much of Nvidia’s contribution came through GPU compute infrastructure rather than direct cash, making the return calculation more nuanced.

CEO Sam Altman’s Equity Remains Undetermined

Perhaps the most striking revelation in the ownership document is that Sam Altman, who has served as OpenAI CEO since 2019, currently possesses zero equity in the organization. His ownership line item shows as undecided. Board chairman Bret Taylor publicly stated in October 2024 that Altman’s equity arrangement had not been finalized. Altman personally refuted speculation about imminent equity grants during an internal employee gathering.

The original OpenAI Foundation nonprofit entity maintains 25.8% ownership with zero capital invested — theoretically producing an infinite return on a holding valued at approximately $219.8 billion. While representing a minority economic interest, the Foundation retains absolute authority over all board member appointments.

OpenAI is preparing for a public market debut targeted for 2026 or early 2027, with discussions centering on a potential $1 trillion valuation. Industry observers anticipate Altman’s ownership compensation will be addressed in connection with that liquidity event.