Quick answer
Greg Brockman's net worth is estimated at $25.5 billion in 2026, according to the Forbes 400 list published in September 2026. The OpenAI co-founder and president debuted on the ranking at No. 45 — the highest-valued newcomer of the year and the tenth-richest person in California. His fortune is almost entirely paper wealth: a stake of slightly under 3% in OpenAI, valued against the company's $852 billion post-money valuation from its March 2026 funding round.
The headline number comes with a striking contrast. OpenAI CEO Sam Altman — Brockman's boss — is worth an estimated $3.3 billion and did not make the Forbes 400 at all, because he holds no direct equity in OpenAI. Brockman's fortune is nearly eight times that of the man who runs the company.
The Forbes 400 debut: No. 45, and the richest newcomer
Forbes' 2026 ranking of America's richest people was, more than anything, a story about AI wealth arriving all at once. Of the 34 newcomers to the list, 14 came from artificial intelligence. Brockman led them. His $25.5 billion debut put him just behind Nike co-founder Phil Knight ($25.8 billion, No. 44) and just ahead of Rupert Murdoch ($25 billion, No. 46).
The AI cohort around him tells the same story. Six Anthropic co-founders — including Dario Amodei and Daniela Amodei — each debuted with an estimated $15.5 billion. The cutoff to make the list this year was $4.4 billion, a record high that kept out a record 590 American billionaires — including Sam Altman himself. Brockman himself was born on November 29, 1987, in Thompson, North Dakota, to two physician parents — about as far from Silicon Valley royalty as a future $25.5 billion fortune can start.
Brockman was, until recently, one of the least visible billionaires on the list. For nearly a decade he worked in the background while public attention focused on Altman. The May 2026 trial in Elon Musk's lawsuit against OpenAI changed that: forced onto the witness stand, Brockman disclosed under oath that his OpenAI stake was worth "over $20 billion, closer to $30 billion" — the first public confirmation of a fortune that had been building quietly since 2015.
The math: how 3% of OpenAI becomes $25.5 billion
Forbes' estimate is not a guess; it is arithmetic on a private-market valuation. In March 2026, OpenAI closed a record $122 billion funding round at a post-money valuation of $852 billion, making it the most valuable private technology company in the world. Forbes estimates Brockman's holding at slightly under 3%.
| Component | Detail |
|---|---|
| OpenAI stake | Slightly under 3% |
| OpenAI valuation (March 2026) | $852 billion post-money |
| 3% × $852B | ≈ $25.56 billion |
| Court testimony (May 2026) | "Over $20B, closer to $30B" |
| Forbes 400 estimate (Sept 2026) | $25.5 billion |
The calculation lands almost exactly on Forbes' figure: 3% of $852 billion is $25.56 billion, and "slightly under 3%" plus his other assets rounds to $25.5 billion. It is worth remembering what this number is not: a market price. OpenAI has no ticker and no public shares. The fortune is a modeled value tied to a negotiated financing round — and it can move sharply the next time the company raises. Reports in September 2026 suggested OpenAI had begun early talks on a new round that could value it at $1.2 trillion or more, which would push Brockman's paper stake toward $35 billion.
The second pile: $471 million in Stripe shares
Before OpenAI, there was Stripe. Brockman joined the payments startup in 2010 as employee number 4, became its chief technology officer by 2013, and left in 2015 to co-found OpenAI. He never sold out completely: he still holds Stripe shares estimated at $471 million, based on Stripe's $159 billion valuation in February 2026.
The Stripe position matters for two reasons. First, it is the only part of his fortune with a relatively liquid, repeatedly re-priced benchmark — Stripe's private valuations have been set by major institutional rounds for over a decade. Second, it shows the pattern of Brockman's wealth: early equity in category-defining companies, held for a very long time. He did the same thing twice — once at Stripe, once at OpenAI — and the second one was roughly fifty times bigger.
For the full story of how those two bets compounded, see how Greg Brockman made his money.
Smaller bets: Cerebras, CoreWeave, Helion and 20+ startups
Beyond the two giants, Brockman's portfolio is modest. Forbes notes small investments totaling less than $5 million in companies including chipmaker Cerebras, cloud provider CoreWeave, and fusion startup Helion — all three of which have done business with OpenAI. As of 2021 he had funded more than 20 startup projects as an angel investor.
These positions are rounding errors next to the OpenAI stake, but they are interesting for what they reveal: Brockman invests almost exclusively in the infrastructure layer of the AI boom — chips, compute, energy. It is the same supply chain OpenAI itself depends on.
The trial that revealed the fortune
Brockman's wealth might have stayed obscure far longer if not for Elon Musk. In the lawsuit Musk brought against OpenAI and its executives — which went to trial in Oakland in April–May 2026 — Brockman was compelled to testify about his holdings. Under questioning from Musk's lawyer, he confirmed his stake was worth over $20 billion, closer to $30 billion, and acknowledged he had never invested a dollar of his own money in OpenAI. The position came entirely from founder and executive equity, granted when the company was a nonprofit research lab with no commercial valuation.
The trial also surfaced a remarkable artifact: a 2017 journal entry in which Brockman wrote, "Financially, what will take me to $1B?" At the time, OpenAI was still a nonprofit and its co-founders were fighting over whether to create a for-profit arm. Nine years later, the answer turned out to be roughly twenty-five times that figure. The jury decided in favor of Altman, Brockman and OpenAI on May 18, 2026, finding Musk's claims barred by the statute of limitations.
Why the president is worth 8x the CEO
The strangest fact on the 2026 Forbes 400 may be an OpenAI one: the company's president is worth nearly eight times its CEO. The explanation is structural. OpenAI began as a nonprofit, and its unusual capped-profit structure was designed to keep incentives tied to the mission rather than personal enrichment. Sam Altman holds no direct equity in OpenAI — he confirmed it under oath — and his estimated $3.3 billion comes from investments made before and alongside his OpenAI tenure, including an early bet on Stripe and his former fund Hydrazine Capital.
Brockman, by contrast, held founder's equity from day one and never gave it up — even when it nearly cost him everything. In November 2023, when OpenAI's board suddenly ousted Altman, Brockman resigned within hours, knowing he might forfeit his equity. Microsoft's Satya Nadella immediately offered both men jobs leading a new AI research team; when Altman was reinstated days later, Brockman returned too. The loyalty gamble preserved the stake that Forbes now values at $25.5 billion.
For a detailed side-by-side, read Greg Brockman vs Sam Altman net worth. For how his pay actually works at a private company, see Greg Brockman's salary.
What could move the number next
Three things will decide whether $25.5 billion is a floor or a peak. First, the next funding round: early talks reported in September 2026 pointed to a valuation of $1.2 trillion or more, which at a constant ~3% stake would put Brockman near $35 billion on paper. Second, an IPO: OpenAI confidentially filed for one in June 2026, though Altman said in September that a 2026 listing would be unwise given safety considerations. A public listing would convert paper wealth into something sellable — and taxable. Third, dilution: every mega-round shrinks his percentage, even as it grows the pie.
One more wrinkle: Brockman has become a major political donor, giving $12.5 million each with his wife to a Trump super PAC in 2025 and $50 million to an AI-deregulation super PAC he helped found — spending he links to OpenAI's mission. In early October 2026 he represented OpenAI at President Trump's White House "Super Intelligence" summit, signing a voluntary AI safety accord in Altman's place. The fortune is no longer just a number on a list; its owner is now a political actor. See the companies behind Brockman's wealth for the full asset map.
Frequently asked questions
What is Greg Brockman's net worth in 2026?
Forbes estimates Greg Brockman's net worth at $25.5 billion as of the 2026 Forbes 400, published in September 2026. He debuted on the list at No. 45, making him the highest-valued newcomer of the year and the tenth-richest person in California.
How did Greg Brockman get his OpenAI stake?
Brockman co-founded OpenAI in late 2015 and received equity as a founder and early executive — first as CTO, later as president. He told a federal court in May 2026 that he never personally invested a dollar of his own money in the company; the entire position came from equity compensation that appreciated as OpenAI's valuation exploded.
What percentage of OpenAI does Greg Brockman own?
Forbes estimates his stake at slightly under 3% of OpenAI. The math checks out: 3% of OpenAI's $852 billion post-money valuation from the March 2026 funding round equals about $25.56 billion — almost exactly Forbes' $25.5 billion estimate. In May 2026 testimony he said the stake was worth over $20 billion, closer to $30 billion.
Does Greg Brockman still own Stripe stock?
Yes. Brockman was employee number 4 and CTO at Stripe from 2010 to 2015, and he still holds Stripe shares worth an estimated $471 million, based on Stripe's $159 billion valuation in February 2026. It is the second-largest piece of his fortune after OpenAI.
Why is Greg Brockman richer than Sam Altman?
Because Altman holds no direct equity in OpenAI — he confirmed this under oath — while Brockman holds nearly 3%. Forbes puts Altman's net worth at about $3.3 billion from outside investments, below the $4.4 billion Forbes 400 cutoff. Brockman's $25.5 billion is nearly eight times his CEO's fortune.
Is Greg Brockman married?
Yes. Brockman married Anna in November 2019 after about a year of dating, in a ceremony held at OpenAI's offices on a workday. Fellow OpenAI co-founder Ilya Sutskever officiated the wedding. The couple keeps a low public profile.
How old is Greg Brockman in 2026?
Reports differ between 37 and 38. Most biographical profiles give his birth date as November 29, 1987, in Thompson, North Dakota, which would make him 38 for most of 2026; Forbes' own tables have listed both 37 and 38.
Where does Greg Brockman live?
Brockman is based in San Francisco, California, where OpenAI is headquartered and where he has lived since his Stripe days. Forbes lists California as his state of residence on the 2026 Forbes 400.