The seven Anthropic co-founders had all worked on a mix of capabilities, safety and policy work at OpenAI.

Judged as of 2026-06-29 against the documented OpenAI roles of the seven Anthropic co-founders (Dario Amodei, Daniela Amodei, Jared Kaplan, Sam McCandlish, Tom Brown, Chris Olah, Jack Clark). True: the evidence shows that, as a group, the founders' OpenAI work covered capabilities, safety and policy, and that each founder took part in more than one of these areas or in cross-cutting work. Mostly true: the group as a whole clearly covered all three areas, but one or two founders' roles were confined to a single area, so 'all' is a little loose. Mixed: the group covered only two of the three areas in any real way, or several founders worked in just one area. Mostly false: the founders' OpenAI work was mostly in one area, for example almost entirely safety or capabilities research, with only token involvement in the others, or some named founders did not work at OpenAI at all. False: the records show the founders' OpenAI work did not include one or more of the named areas at all, or most founders were not at OpenAI.

Set before the research began.

1. E1 Anthropic's filing for blockbuster US IPO shows key executives and board Economic Times · 26 October 2026

   “VP of Safety and Policy at OpenAI, which she left along with her brother, Dario.”

2. E2 How Anthropic Designed Itself to Avoid OpenAI’s Mistakes - TIME TIME · 30 May 2024

   “Anthropic’s seven co-founders all previously worked at OpenAI. In his former role as OpenAI’s vice president for research, Anthropic CEO Dario Amodei even wrote the majority of OpenAI’s charter,”

3. E3 Anthropic's filing for blockbuster US IPO shows key executives and board Economic Times · 26 October 2026

   “Research lead for GPT-3 at OpenAI.”

4. E4 Daniela Amodei at OpenAI (2018–2020) and Why She Left Not identified on page (amodei.co profile site) · 29 October 2026 Own record

   “She joined in 2018, managed teams including the one around GPT-2, and became VP of Safety and Policy.”

5. E5 How Anthropic Designed Itself to Avoid OpenAI’s Mistakes TIME · 30 May 2024

   “Anthropic’s seven co-founders all previously worked at OpenAI.”

6. E6 How Anthropic Designed Itself to Avoid OpenAI’s Mistakes TIME · 30 May 2024

   “In his former role as OpenAI’s vice president for research, Anthropic CEO Dario Amodei even wrote the majority of OpenAI’s charter, the document that commits the lab and its workers to pursue the safe development of powerful AI.”

7. E7 Written Testimony of Jack Clark Policy Director OpenAI U.S. House Permanent Select Committee on Intelligence (hearing record, docs.house.gov) · June 2019

   “My name is Jack Clark. I’m the Policy Director for OpenAI, an artificial intelligence research company in San Francisco, California.”

8. E8 The Ghost in the Machine · GPT-3 Oral History Context Jamming (ACRA Insight LLC) · 18 July 2026

   “*Daniela Amodei*VP of Safety and Policy, OpenAI”

9. E9 Sam McCandlish - People in crypto | IQ.wiki IQ.wiki · 3 July 2026

   “McCandlish joined OpenAI in 2017 and served as a Member of Technical Staff from May 2018 to December 2020. During this period, he participated in the AI Safety Fellowship, established the Science of AI team, and led the early development of Codex.”

10. E10 Chris Olah — on the record | Vigilia Vigilia · 30 May 2023

    “2018 – 2020Lead, interpretability team, OpenAI”

The evidence shows that all seven co-founders worked at OpenAI (E5). It also shows that the group's work included research (E3, E6), safety (E6, E9, E10) and policy (E1, E7). It gives no OpenAI role for Jared Kaplan and does not name Tom Brown. Under the criteria, the choice between mostly true and mixed depends on how many founders worked in only one area, and the evidence does not settle that.