Sam McCandlish
American physicist and AI researcher; co-founder and chief architect of Anthropic
| Sam McCandlish
| |
|---|---|
| Born | 1990 (Forbes) |
| Nationality | American |
| Residence | San Francisco, California (Forbes) |
| Occupation | AI researcher and executive |
| Known for | Co-founder of Anthropic; neural scaling laws |
| Education | Brandeis University (BA, mathematics and physics); Stanford University (PhD, physics) |
Sam McCandlish (born 1990) is an American theoretical physicist and machine-learning researcher. He is one of the seven co-founders of Anthropic, which they started in January 2021 after leaving OpenAI.[1][2] On 11 November 2026 the Forbes Real-Time Billionaires list ranked McCandlish 237th in the world, with an estimated net worth of US$13.1 billion; Forbes lists the source of wealth as artificial intelligence.[1][3] In the annual World's Billionaires list published in 2026, Forbes had ranked McCandlish 567th, at US$7.0 billion.[4] Anthropic's amended IPO filing of 10 November 2026 gives his title as chief architect, while Forbes calls him chief technology officer.[2][1] The filing shows him as the beneficial owner of 243,383,850 Class A shares, 3.7% of that class.[2]
Education
McCandlish has a bachelor's degree in mathematics and physics from Brandeis University and a PhD in physics from Stanford University.[2] Forbes describes the doctorate as being in theoretical physics.[1]
OpenAI
Forbes says McCandlish spent three years as a member of the technical staff at OpenAI.[1] Anthropic's filing says he built and led a team there focused on the science and scaling of machine learning. It credits his work on scaling laws with helping to pave the way for large-scale advances in AI, including GPT-3.[2] He was second author, after Jared Kaplan, of the 2020 paper Scaling Laws for Neural Language Models. That paper found that model loss scales as a power law with model size, dataset size and training compute.[5] He was also an author of the 2020 GPT-3 paper, Language Models are Few-Shot Learners.[6]
Anthropic
The filing describes McCandlish as specialising in large-scale model training and AI systems architecture.[2] He was a co-author of Anthropic's 2022 paper on "Constitutional AI", a training method in which the only human oversight comes from a list of rules or principles.[7] Forbes says Anthropic has partnerships with Alphabet and Amazon, and that private investors valued it at US$965 billion in May 2026.[1]
Listing and ownership
Anthropic filed to list on the Nasdaq under the symbol "ANT", with an indicated price range of US$70–78 a share in its 10 November 2026 amended filing. It said that the seven co-founders had each pledged to give 80% of their personal Anthropic equity to philanthropy, describing the pledges as voluntary and revocable rather than legally binding.[2] A single Class F share held by a founders' LLC will carry 50.1% of the votes.[2] TechCrunch reported that each co-founder would sell 3,378,378 shares in the offering, worth just under US$250 million each at the midpoint of the range.[8] Fortune estimated that each co-founder owned about 1.4% of the company on a fully diluted basis.[9] In its 26 October 2026 report, based on the original filing, Fortune listed McCandlish with 231,809,780 shares.[9]
Dispute with the Department of War
Anthropic's filing says that in February 2026, after the company stated that its technology should not be used for mass domestic surveillance or fully autonomous weapons, the President directed federal agencies to stop using it and the Secretary of War ordered it designated a "supply-chain risk to national security". A federal district court in California largely granted Anthropic summary judgment on 27 August 2026, but on 25 September 2026 a divided D.C. Circuit panel upheld one of the designations. Anthropic has asked for a rehearing by the full court.[2]
Political activity
FEC records for the 2022–2026 cycles show one itemised federal contribution by McCandlish: US$5,000 to the Anthropic PBC Political Action Committee on 30 April 2026.[10]
Across the 1 non-memo records retrieved for the 2022–2026 cycles, the filtered total is US$5,000 (a lower bound). The largest recipient committees, as named in the filings, were ANTHROPIC PBC POLITICAL ACTION COMMITTEE (US$5,000).[10]
| Cycle | Total (US$, lower bound) | Records | Largest recipient committees (as filed with the FEC) |
|---|---|---|---|
| 2026 | $5,000 | 1 | ANTHROPIC PBC POLITICAL ACTION COMMITTEE ($5,000) |
Philanthropy
Like the other co-founders, McCandlish has pledged to give 80% of his personal Anthropic equity to philanthropy. Anthropic describes this as a voluntary and revocable commitment.[2]
Wealth
Forbes classes McCandlish as self-made, with wealth from artificial intelligence.[1]
Wealth history
Forbes has included this entry in its annual World's Billionaires list in 2 of the editions from 2001 to 2026 checked for this profile, starting with 2025. The table gives the rank and estimated net worth in each annual list, and, where applicable, the rank and estimate in the Forbes 400 list of the richest Americans.[4][1]
| Year | World's Billionaires rank | Net worth (US$ bn) | Forbes 400 rank | Forbes 400 net worth (US$ bn) |
|---|---|---|---|---|
| 2025 | 2623 | 1.2 | – | – |
| 2026 | 567 | 7.0 | 75 | 15.5 |
International and political links
This section uses the same ten headings for every profile in this series. Only specific, sourced actions are included; company-level and foundation-level actions are labelled as such. Where nothing was found, the entry reads "No documented involvement found in sources checked."
Israel (investments, operations, donations, contracts, statements)
No documented involvement found in sources checked.
Zionist or pro-Israel organisations and lobbying groups
No documented involvement found in sources checked.
Jewish communal charities
No documented involvement found in sources checked.
Gulf states
No documented involvement found in sources checked.
China
No documented involvement found in sources checked.
Russia
No documented involvement found in sources checked.
India
No documented involvement found in sources checked.
Palestinian or Arab causes
No documented involvement found in sources checked.
Home government
Anthropic's filing says that in February 2026, after the company stated that its technology should not be used for mass domestic surveillance or fully autonomous weapons, the President directed federal agencies to stop using it and the Secretary of War ordered it designated a "supply-chain risk to national security". A federal district court in California largely granted Anthropic summary judgment on 27 August 2026, but on 25 September 2026 a divided D.C. Circuit panel upheld one of the designations. Anthropic has asked for a rehearing by the full court.[2]
Other international links
No documented involvement found in sources checked.
See also
Notes
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Forbes, Forbes profile record for Sam McCandlish (Forbes data feed behind forbes.com/profile/sam-mccandlish/) Forbes, live record, read 11 November 2026, accessed 11 November 2026.
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 Anthropic, PBC, Form S-1/A (Amendment No. 2) registration statement U.S. Securities and Exchange Commission, 10 November 2026, accessed 11 November 2026.
- ↑ Forbes, Forbes Real-Time Billionaires data feed Forbes, live; downloaded 11 November 2026 07:10 UTC, accessed 11 November 2026.
- ↑ 4.0 4.1 Forbes, Forbes World's Billionaires list data feed, annual editions 2001–2026 (one file per year at this path with the year substituted; all 26 files downloaded and read) Forbes, annual lists; downloaded 20 October 2026, accessed 11 November 2026.
- ↑ Jared Kaplan et al., Scaling Laws for Neural Language Models arXiv:2001.08361, 23 January 2020, accessed 11 November 2026.
- ↑ Tom B. Brown et al., Language Models are Few-Shot Learners arXiv:2005.14165, 28 May 2020, accessed 11 November 2026.
- ↑ Yuntao Bai et al., Constitutional AI: Harmlessness from AI Feedback arXiv:2212.08073, 15 December 2022, accessed 11 November 2026.
- ↑ Julie Bort, All 7 Anthropic founders will each cash out about $250M in IPO TechCrunch, 10 November 2026, accessed 11 November 2026.
- ↑ 9.0 9.1 Nick Lichtenberg, Anthropic’s 7 cofounders are each worth $14 billion already—and that could double in an IPO. They’ve promised to give most of it away Fortune, 26 October 2026, accessed 11 November 2026.
- ↑ 10.0 10.1 U.S. Federal Election Commission, OpenFEC Schedule A (itemised individual contributions) query, contributor name "MCCANDLISH, SAM"; 2026 cycle shown in link, the 2022, 2024 and 2026 cycles were queried together with the same parameters; top 100 records by amount; records filtered by employer/occupation and name, memo entries excluded U.S. Federal Election Commission, data as filed; queried 11 November 2026, accessed 11 November 2026.