Seven people quit OpenAI to co-found Anthropic in January 2021. Five-and-a-half years later, each of them owns almost exactly the same slice of the AI company that just officially released its paperwork for an initial public offering. Each founder own about 240 million shares, according to the S-1 registration statement Anthropic filed with the Securities and Exchange Commission on Monday.
At $58.90 a share — the split-adjusted price investors paid in Anthropic’s most recent private funding round this spring—each stake would be worth between $13.7 billion and $14.4 billion. Together the seven hold about 1.69 billion shares, roughly 10% of the company.
If Anthropic lists at the roughly $2 trillion valuation that Wall Street estimates have pointed to, each co-founder would be worth between $27 billion and $29 billion.
The seven cofounders are:
- CEO Dario Amodei
- his sister Daniela Amodei, the company’s president and board chair
- Tom Brown, chief compute officer
- Jared Kaplan, chief science officer
- Sam McCandlish, chief architect
- Chris Olah, who leads interpretability research
- Jack Clark, who leads the Anthropic Institute
All seven are listed as selling stockholders in the offering. How many shares each plans to sell is left blank.
Benjamin Mann has been with Anthropic since its founding and “is often referred to as a co-founder,” the filing says. But he isn’t a member of the founders’ LLC, so he won’t help decide how the controlling Class F share votes. The S-1 says its references to “co-founders” don’t include him. He isn’t in the ownership table either, so his stake isn’t disclosed.
The math
The share counts come from the filing’s beneficial ownership table, as of Sept. 30, 2026. Each figure includes the shares a co-founder holds directly or through trusts, plus 2,185,400 stock options and 639,500 restricted stock units that vest within 60 days.
| Co-founder | Role | Shares | Value at $58.90 | Value at $2 trillion IPO |
|---|---|---|---|---|
| Tom Brown | Chief compute officer | 244,173,040 | $14.4 billion | $28.8 billion |
| Chris Olah | Interpretability research lead | 242,882,420 | $14.3 billion | $28.7 billion |
| Jared Kaplan | Chief science officer | 242,351,170 | $14.3 billion | $28.6 billion |
| Jack Clark | Head of the Anthropic Institute | 242,271,840 | $14.3 billion | $28.6 billion |
| Daniela Amodei | President and board chair | 241,408,940 | $14.2 billion | $28.5 billion |
| Dario Amodei | CEO | 240,637,980 | $14.2 billion | $28.4 billion |
| Sam McCandlish | Chief architect | 231,809,780 | $13.7 billion | $27.4 bilion |
Daniela Amodei’s count includes about 264,500 options and RSUs held by her spouse. Dario Amodei is listed with 245 million shares in total, but 4.6 million of those sit in donor-advised funds; he votes them under proxy agreements but no longer owns them. Including them, his fortune would be worth $14.4 billion at the Series H price and about $29 billion in a $2 trillion IPO, moving him from sixth to first in the table.
The $58.90 price comes from the company’s Series H funding round. Between May and June, Anthropic sold 77.6 million shares of Series H-1 preferred stock at $589.0095 a share, raising $45.7 billion. On Sept. 17, the company split its Class A and Class N common stock 10-for-1 and adjusted the preferred stock’s conversion rate to match. Each Series H share now converts into 10 common shares, which puts the round at $58.90 per common share.
The filing doesn’t give a total share count, but it gives enough information to estimate one. Anthropic says the 846.8 million shares it put into its new Anthropic Public Benefit Fund equal 5% of its fully diluted shares as of June 30, assuming Amazon’s convertible notes fully convert. That works out to about 16.9 billion shares, so each co-founder owns about 1.4% of the company.
A private-round price is only a rough guide. Series H buyers got preferred stock with rights common holders don’t have, and the co-founders’ options carry exercise prices the ownership table doesn’t list. The $2 trillion figure appears nowhere in the prospectus. It comes from Wall Street estimates reported in the press before the filing. The S-1 leaves the price range, the number of shares being sold and the post-offering share count blank. Anthropic will fill them in with an amended filing before it starts marketing the stock to investors.
Turning a headline valuation into a per-founder number takes two figures the filing doesn’t have yet. One is the price per share. The other is the total share count after the IPO, which will include new stock sold in the offering, Amazon’s notes converting into Class N shares and employee RSUs that settle at listing. Until then, Fortune’s calculation divides by the roughly 16.9 billion fully diluted shares implied by the filing, which puts a $2 trillion valuation at about $118 a share. Valuations quoted in the press don’t always say which share count they use, so the real figure could move once the price range is public.
An 80% pledge with no strings
Each co-founder has pledged to give 80% of their personal Anthropic equity to philanthropic causes. The filing calls the pledges “voluntary, revocable expressions of each co-founder’s philanthropic intent and do not constitute legally binding obligations.” The timing, amounts and recipients are all undecided, and the founders may route the money through donor-advised funds, charities or private foundations.
Giving the money away doesn’t mean giving up control. A single share of Class F stock, held by an LLC owned by the seven co-founders, carries 50.1% of the company’s vote and no economic rights. A co-founder stays in that LLC as long as they keep at least 2% of the Class A shares they held at the IPO. That means a co-founder could give away 98% of their stake and still help decide how the controlling share votes.
The filing names the problem itself. As the founders give stock away, it says, their economic interest shrinks while their voting control stays the same. “As our co-founders make donations in furtherance of this pledge, their personal economic interests in us will decrease while their voting control through the Founder LLC will remain unchanged … which may reduce the alignment between the interests of our co-founders and those of our other stockholders, or cause those interests to diverge.”
The founders are subject to a standard 180-day lockup, which the lead underwriters, Goldman Sachs and Morgan Stanley, can waive early.
Who else gets paid
Two of Anthropic’s biggest backers don’t show up in the ownership table at all. Amazon and Google will both hold nonvoting Class N stock after the offering, and the table covers only holders of more than 5% of a voting class. Their actual share counts are left blank. Amazon’s convertible notes stop converting once it would own more than 12% of the company, and Google’s latest investment deal caps its stake at 14.99%. Either ceiling is above the roughly 10% the seven co-founders hold together.
The co-founders’ pay is relatively small. Dario Amodei collected $17.96 million in total compensation in 2025, including a $654,167 salary. Daniela Amodei made $16.4 million. CFO Krishna Rao earned $720,250 last year, but he holds about 9.5 million shares, mostly in options. At the Series H price, that stake is worth about $559 million before exercise costs. His original offer letter was terminated this month and replaced with a new agreement.
The Anthropic Public Benefit Fund, a wholly owned subsidiary created for the company’s public benefit mission, holds 846.8 million shares. At $58.90, that block is worth about $49.9 billion, more than three of the co-founders put together. One of its first managers is expected to be co-founder Jack Clark.
Generative AI was used for research assistance and/or transcription of this article. The reporter independently reported and verified the factual claims in this article, and a human editor reviewed it before publication.
