Anthropic's Founders Hold 10%, Control 50.1%, and Five Are Selling

Why it matters

Anthropic is a controlled company with a founder block that sells. The April 2026 tender, run by a syndicate of existing holders at exactly the Series G price, is the template: insiders cleared $4.66 billion a month before the Series H priced 127% higher. The IPO is the next window, and five of the seven founders are already in the selling column. For anyone holding through an SPV, the question is not whether insiders sell but at what price, and the filing says the founders' first price was $5.61 and their second was $25.91.

The founder cap table

Beneficial ownership as of the filing, post-split. Each founder's figure includes about 2.2 million options exercisable within 60 days and shares held in trusts.

Dario Amodei also votes a further 4.6 million shares held by two donor-advised funds under irrevocable proxies. Krishna Rao, the CFO, holds 9.5 million, of which 7.8 million are options. Reed Hastings holds 9,410 shares. All executive officers and directors together hold 496.4 million. The percentage column in the filing is blank: it needs the share count that comes with the price range.

Two tenders, two prices

The April price was the Series G price. Six weeks later the Series H closed at $58.90. The secondary prints PMView recorded from April to July averaged $66.60 post-split. Anyone who bought common at "a discount to the round" this spring bought from this tender or around it.

Control, and what it costs the public

Immediately before the offering the seven founders form a limited liability company and receive one share of Class F stock. That share votes 50.1% of the company on all matters put to stockholders, including the election of directors other than the Class T directors. The Long-Term Benefit Trust holds the one Class T share and elects a majority of the board. Together the two can seat every director. Amazon, Google and Broadcom hold or will hold non-voting Class N. The Class A stock sold in the IPO has one vote per share and, in aggregate, never more than 49.9%.

The founders' lockup runs until the earlier of two trading days after the third-quarter 2027 earnings release or the 365th day after the prospectus, subject to the staged releases the filing describes for holders above 0.5% of the company. Employees below that line start at 10% on the first day of trading. The founders are the last supply, not the first.

Sources

• Anthropic, PBC Form S-1, filed October 26, 2026 (SEC accession 0001628280-26-067168): Principal and Selling Stockholders; Certain Relationships and Related Person Transactions, Tender Offers; Our Governance Structure and Its Goals; Shares Eligible for Future Sale; Recent Sales of Unregistered Securities.
• PMView: Anthropic, cap table, team, secondary market price.