People

Greg Brockman

American computer scientist and entrepreneur, co-founder and president of OpenAI, who was previously chief technology officer at Stripe, resigned from OpenAI's board in November 2023 during Sam Altman's brief ouster, and took a sabbatical from August to November 2024.

Researched by Muhammad Abdullah Al Yasin · 11 September 2026 · updated 13 September 2026

Country

United States

Known for

Co-founder and president of OpenAI; earlier its chief technology officer; previously chief technology officer of Stripe

Education

Studied mathematics at Harvard University, transferred to MIT after his sophomore year, and left MIT in 2010 without completing a degree

Career before OpenAI

Joined Stripe in 2010 as an early engineer and later became its chief technology officer, leaving in 2015

OpenAI roles held

Co-founder and chief technology officer at OpenAI's December 2015 launch; later president; also chairman of the board until November 2023

2025–2026 focus

Described in business press as leading OpenAI's data-center and computing-infrastructure buildout, including the Stargate project

Timeline

2007

Places sixth in the Society for Science's Science Talent Search for a paper titled "Asymptotic Behavior of Certain Ducci Sequences."

2010

Leaves Harvard for MIT after his sophomore year, then leaves MIT without a degree to join the payments company Stripe as an early engineer.

2013

By his own account, is formally named Stripe's chief technology officer roughly this year, after joining in 2010 as an engineer.

2015-12-11

Co-founds OpenAI as a nonprofit research lab alongside Sam Altman, Elon Musk and others, taking the title of chief technology officer.

2018-06-26

Testifies before a U.S. House of Representatives committee, submitting a biography describing himself as OpenAI's co-founder and CTO and an investor in more than 30 startups.

2023-11-17

Is removed as board chairman and, hours after OpenAI's board fires Sam Altman as CEO, resigns from the company entirely, posting on X/Twitter "based on today's news, I quit."

2023-11-20

Joins Microsoft alongside Altman as Microsoft CEO Satya Nadella announces the pair will lead a new advanced AI research team there.

2023-11-21

Returns to OpenAI as Altman is reinstated as CEO under a new board, following a letter signed by nearly all OpenAI staff demanding both men's reinstatement.

2024-08-05

Announces on X that he is taking a leave from OpenAI through the end of the year, writing it is his "first time to relax since co[-]founding OpenAI nine years ago."

2024-11-12

Announces his return to OpenAI as president, about three months after going on leave, posting that his "longest vacation" was complete and he was "back to building OpenAI."

2025-11-05

Fortune profiles Brockman as OpenAI's "builder-in-chief," describing him as overseeing the company's data-center and infrastructure buildout, including the Stargate project.

2026-04

Testifies as a witness in the federal trial of Elon Musk's lawsuit against OpenAI, Sam Altman, and Microsoft, alongside Musk, Altman, Microsoft CEO Satya Nadella, and former OpenAI board members Helen Toner and Tasha McCauley.

2026-09

In an interview, describes his 2026 focus as building out OpenAI's leadership team rather than hands-on technical work, saying he has "replaced" the feeling of coding "with something I love even more."

What we could not verify

These claims came up in research and could not be confirmed. They are recorded here rather than published as fact or quietly dropped. If you hold a source that settles one, please tell us.

• No independently verified birth date or birthplace was located in a source read for this profile; none is stated.
• The exact date Brockman's title changed from OpenAI chief technology officer to president is not confirmed by an independent source read for this profile; only that he held the CTO title at OpenAI's December 2015 founding and was already described as "president" (and board chairman) by November 2023.
• Exactly when Brockman became chairman of OpenAI's board is not stated in any source read for this profile.
• Sources disagree on whether Brockman was made Stripe's CTO immediately upon joining in 2010 or roughly three years later; see sourceNote. This profile does not resolve that discrepancy.
• No source read for this profile details what Brockman did during his August–November 2024 leave beyond his own characterization of it as rest; none is asserted.
• Whether Brockman was ever formally a named defendant in Elon Musk's lawsuit against OpenAI is not resolved here: one source used in this site's Elon Musk profile claims he was added as a defendant in an August 2024 filing, while another, independent tier1 source's account of the November 2024 amended complaint does not list him among the defendants. This profile states only his confirmed role as a trial witness, not a defendant.

Sources

14 sources (8 tier 1, 4 tier 2, 2 first-party), each opened and read against the claim it supports. Statements the subject makes about itself are marked as such and are not treated as independent evidence. See the source policy.

This profile covers Brockman's documented professional and public record. Two source discrepancies are flagged rather than silently resolved: (1) Fortune's November 2025 profile states Brockman joined Stripe in 2010 already as its "first CTO," while Brockman's own 2014 blog post says he joined as an engineer in 2010 and was made CTO roughly a year and a half before that October 2014 post (early 2013) — both accounts are given. (2) Some existing reference works have stated Brockman's 2024 leave ran into November 2025; contemporaneous reporting from multiple outlets in November 2024 — including his own announcement — confirms he returned to OpenAI on or immediately after November 12, 2024, roughly three months after his early-August 2024 leave announcement, not in 2025. This profile states the November 2024 date on that contemporaneous sourcing.

1. Federal court rejects Elon Musk's claims against OpenAI, saying he filed his lawsuit too late — PBS NewsHour, 2026-05-18 · Tier 1 Supports: Confirming Brockman testified as a witness at the April 2026 federal trial of Musk's lawsuit against OpenAI, Altman, and Microsoft, alongside Musk, Altman, Microsoft CEO Satya Nadella, and former OpenAI board members Helen Toner and Tasha McCauley. This profile does not independently confirm whether Brockman was ever formally named as a defendant in the case (see the Elon Musk profile, whose sources conflict on that point) and states only his documented role as a witness.
2. Non-Profit OpenAI Launches With Backing From Elon Musk And Sam Altman — TechCrunch, 2015-12-11 · Tier 1 Supports: OpenAI's December 11, 2015 launch as a nonprofit research lab, Sam Altman and Elon Musk as co-chairs, and confirmation that Brockman — named as Stripe's former CTO — took the same CTO title at OpenAI.
3. Greg Brockman quits OpenAI after abrupt firing of Sam Altman — TechCrunch, 2023-11-17 · Tier 1 Supports: The November 17, 2023 sequence in which Brockman was removed as board chairman, learned of Altman's firing, and then resigned entirely from OpenAI, including his exact "based on today's news, I quit" quote.
4. Microsoft hires ex-OpenAI leaders Sam Altman and Greg Brockman to lead new AI team — TechCrunch, 2023-11-20 · Tier 1 Supports: Confirmation that Brockman joined Microsoft alongside Altman on November 20, 2023, as Microsoft CEO Satya Nadella announced a new advanced AI research team, with other former OpenAI staff following.
5. OpenAI reinstates Sam Altman as its chief executive — NPR, 2023-11-22 · Tier 1 Supports: Confirmation that Brockman — described as "a board member and the former president of OpenAI who quit in protest" — joined Microsoft with Altman and then returned to OpenAI as part of Altman's November 21, 2023 reinstatement, driven partly by a staff letter that specifically demanded both men's reinstatement.
6. OpenAI, Sam Altman and the exodus rattling the AI world's most valuable startup — Fortune, 2024-08-06 · Tier 1 Supports: Brockman's early-August 2024 announcement of a leave from OpenAI through the end of the year, and his quoted statement that it was his "first time to relax since co[-]founding OpenAI nine years ago."
7. OpenAI's grasp builder: Greg Brockman is steering a $1.4 trillion infrastructure surge — Fortune, 2025-11-05 · Tier 1 Supports: Independent confirmation that Brockman left Harvard for MIT and dropped out in 2010 to join Stripe, co-founded OpenAI in 2015 and largely ran it operationally in its early years, was removed from OpenAI's board in November 2023, took a leave beginning August 2024 that he described in the same terms reported elsewhere, returned in November 2024, and by late 2025 was described as OpenAI's "builder-in-chief" leading its data-center and infrastructure buildout including the Stargate project.
8. Former OpenAI executive Sutskever discloses nearly $7 billion stake in AI firm — The Associated Press (via WTVB), 2026-05-11 · Tier 1 Supports: Confirming Ilya Sutskever's May 11, 2026 testimony at the same trial Brockman testified in, and his disclosed OpenAI equity stake valued at about $7 billion.
9. Greg Brockman — Society for Science · Tier 2 Supports: His sixth-place finish in the 2007 Science Talent Search for a paper on Ducci sequences, and his subsequent inclusion in Forbes' 2018 "30 Under 30" and TIME's 2023 TIME100 AI list.
10. OpenAI co-founder Greg Brockman returns to ChatGPT maker — Yahoo Finance, 2024-11-12 · Tier 2 Supports: Confirming Brockman's return to OpenAI on/around November 12, 2024, roughly three months after his leave began, his "longest vacation of my life complete" post, and reporting that he and Altman were shaping a new role for him focused on technical challenges.
11. OpenAI co-founder Greg Brockman returns after three months of leave — NBC New York (CNBC wire content), 2024-11-12 · Tier 2 Supports: Corroborating the November 12, 2024 return date, the "three months of leave" characterization (leave beginning August 2024), his "back to building OpenAI" quote, and his title as OpenAI president.
12. An Interview with OpenAI President Greg Brockman About Astra and Alignment — Stratechery (Ben Thompson), 2026-09 · Tier 2 Supports: Detailed, independently reported confirmation of the Harvard-to-MIT education path, leaving MIT in 2010 for Stripe, becoming Stripe's CTO and leaving in 2015 to co-found OpenAI, his 2024 sabbatical, and his direct quote on shifting his focus in 2026 from hands-on coding to building OpenAI's leadership team.
13. #define CTO — Figuring out the CTO role at Stripe — Greg Brockman (personal blog), 2014-10-27 · First-party Supports: Brockman's own account that he joined Stripe as an engineer in 2010 and was formally made CTO roughly a year and a half before this October 2014 post (so around early 2013).
14. Greg Brockman — U.S. House of Representatives (committee hearing record; self-submitted biography), 2018-06-26 · First-party Supports: Confirmation that Brockman studied mathematics at Harvard and computer science at MIT, his description of himself as OpenAI's co-founder and CTO as of mid-2018, and his self-reported roles as an investor in more than 30 startups and a board member of Stellar.