Altman was born on April 22, 1985, in Chicago, Illinois,[10] into a Jewish family,[11] and grew up in St. Louis, Missouri. His mother was a dermatologist, and his father a real estate broker. Altman is the eldest of four siblings.[3] At the age of eight, he received his first computer, an Apple Macintosh, and began to learn how to code and take apart computer hardware.[12][13] He attended John Burroughs School, a private school in Ladue, Missouri.[14] In 2005, after two years at Stanford University studying computer science, he dropped out without earning a bachelor's degree.[15][16]
In 2011, Altman became a partner at Y Combinator (YC), a startup accelerator that invests in a wide range of startups, initially working on a part-time basis.[21] In February 2014, he became president of YC.[22] In a 2014 blog post, Altman stated that the total valuation of YC companies had surpassed $65 billion, including Airbnb, Dropbox, Zenefits, and Stripe.[23] He aimed to expand YC to fund 1,000 new companies per year and sought to broaden the types of companies funded, particularly focusing on "hard technology" startups.[24]
In October 2015, Altman was involved in expanding YC's scope. He contributed $10 million to the initial fund of Y Combinator Research, and announced YC Continuity, a fund to invest in maturing YC companies.[25][26][27] In September 2016, Altman's role at YC expanded to president of YC Group, which included Y Combinator and other units.[28]
In March 2019, YC announced Altman's transition from president to a less hands-on role as chairman of the board, allowing him to focus on OpenAI.[29][30] This decision came shortly after YC announced it would be moving its headquarters to San Francisco.[21] As of early 2020, he was no longer affiliated with YC.[31] It was later revealed that he had falsely claimed the board chair title (including in SEC filings), and that Y Combinator partners never approved his appointment.[32][33]
As of June 2024, Altman's investment portfolio includes stakes in over 400 companies, which are valued at around $2.8 billion. Some of these investments intersect with companies doing business with OpenAI, which has raised questions about potential conflicts of interest. OpenAI’s chairman of the board, Bret Taylor, maintained that Altman has been transparent about his investments.[34]
In April 2012, Altman co-founded Hydrazine Capital with his brother, Jack Altman.[35][36] The University of Michiganendowment was the only outside investor in Hydrazine's 2023 funding round. Its investments in Hydrazine were the largest the endowment has made.[37] Altman debuted on the Bloomberg Billionaires Index in March 2024 with an estimated net worth of $2 billion, primarily from his venture capital funds related to Hydrazine Capital.[38]
Nancy Pelosi presenting Altman with the Ric Weiland Award in 2017
Altman has several other investments in companies including Humane, which was developing a wearable AI-powered device; Retro Biosciences, a research company aiming to extend human life by 10 years;[43]Boom Technology, a supersonic airline developer; Cruise, a self-driving car company that was acquired by General Motors; and Helion Energy, an American fusion research company.[44]
During the COVID-19 pandemic, Altman helped fund and create Project Covalence to help researchers rapidly launch clinical trials in partnership with TrialSpark, a clinical trial startup.[45] During the depositor run on Silicon Valley Bank in mid-March 2023, Altman provided capital to multiple startups.[46] Altman invests in technology startups and nuclear energy companies. Some of his portfolio companies include Airbnb, Stripe and Retro Biosciences.[43]
Along with Peter Thiel, Altman was an early seed investor in Minicircle, "a longevity biotech company focused on developing gene therapies to extend human lifespans."[47] He also invested in charter city projects Próspera and Praxis,[48] which have gotten additional financial support from author and former Coinbase CTO, Balaji Srinivasan.[49] Both cities have been linked by various publications and journalists to the Network State movement.[50]
For eight days in 2014, Altman was the CEO of Reddit, a social media company, after CEO Yishan Wong resigned.[51][52] On July 10, 2015, he announced the return of Steve Huffman as CEO.[53] He remained on its board until 2022.[54] Altman invested in multiple rounds of funding Reddit, in 2014, 2015, and 2021.[54][55] Prior to Reddit's initial public offering in 2024, Altman was listed as its third-largest shareholder, with around nine percent ownership.[56]
In 2019, Altman co-founded the for-profit company Tools For Humanity.[57] The company promoted the Worldcoincryptocurrency and eye scanning systems to provide proof of personhood and authentication.[58][59] The company engaged in deceptive marketing practices to drive sign ups.[60][61] By 2023, Tools For Humanity had scanned two million people's eyes and raised $250 million from several investors including Andreessen Horowitz and Sam Bankman-Fried.[62][57][63]
Kenya was one of the first countries to register WorldCoin. The promise of free money lead to rapid growth in Kenya until WorldCoin promotion was paused by regulators.[64] Citing legal concerns over biometric data privacy and potential fraud concerns, regulators in France, the United Kingdom, Bavaria, South Korea, Spain, Portugal, and Hong Kong have investigated or suspended WorldCoin.[65] WorldCoin has never been offered in the United States and the company limits its disclosures due to regulatory scrutiny.[62]
Altman is chairman of the board for Helion Energy, a company focused on developing nuclear fusion.[66][67]
He also invested in Exowatt, a solar energy startup that aims to provide clean energy to data centers.[68]
In March 2021, Altman and investment banker Michael Klein co-founded AltC Acquisition Corp, a special-purpose acquisition company (SPAC), where he was also the CEO.[7][69] In May 2024, Oklo Inc. completed a merger with the SPAC to become a public company. Altman remained as chairman of Oklo following the merger[70] until stepping down in April 2025 to "avoid conflict of interest"[71] and "open up opportunities for future deals between OpenAI and Oklo."[72]
Altman stated in 2015 that they were partly motivated by concerns about AI safety and existential risk from artificial general intelligence.[76][77] OpenAI stated that "it's hard to fathom how much human-level AI could benefit society", and that it is equally difficult to comprehend "how much it could damage society if built or used incorrectly".[78] The startup also wrote that AI "should be an extension of individual human wills and, in the spirit of liberty, as broadly and evenly distributed as possible",[78] and that "because of AI's surprising history, it's hard to predict when human-level AI might come within reach. When it does, it'll be important to have a leading research institution which can prioritize a good outcome for all over its own self-interest."[79] Altman expected a decades-long project that eventually surpasses human intelligence.[80]
Co-founder Greg Brockman was able to hire 52 employees in the first year. Many of these were top AI research talent that left high paying jobs for the opportunity at OpenAI.[81][82]Walter Isaacson opined that Altman had "Musk-like intensity".[83]
In 2017, OpenAI spent $7.9 million, a quarter of its functional expenses, on cloud computing alone.[84] In comparison, DeepMind's total expenses in 2017 were $442 million.[85]
In 2018, Musk, a long-time personal friend of Altman's, resigned from his Board of Directors seat, citing "a potential future conflict [of interest]" with his role as CEO of Tesla due to Tesla's AI development for self-driving cars.[86][82] In February 2024, Musk sued OpenAI and Altman, alleging they broke the company's founding agreement by prioritizing profit over benefit to humanity.[87] OpenAI executives, including Altman, dismissed these claims in a blog post.[88] The post said that the startup received only $45million from Musk instead of his pledged $1billion, and that Musk proposed to merge it with Tesla.[89]
In March 2019, Altman left Y Combinator to focus full time on OpenAI as CEO.[90][2] OpenAI planned to spend $1 billion "within five years, and possibly much faster".[91] Altman stated that even a billion dollars may turn out to be insufficient, and that the lab may ultimately need "more capital than any non-profit has ever raised" to achieve artificial general intelligence (AGI).[92] OpenAI transitioned from non-profit to "capped" for-profit, with the profit being capped at 100 times any investment.[93] According to OpenAI, the capped-profit model allows OpenAI Global, LLC to legally attract investment from venture funds and grant employees stakes in the company.[85] Some researchers have argued that OpenAI Global, LLC's switch to for-profit status is inconsistent with OpenAI's claims to be "democratizing" AI.[94] OpenAI also announced Microsoft's additional $1 billion into the company. Their systems have since run on an Azure-based supercomputing platform.[95][96][97]
In December 2022, OpenAI received widespread media coverage after launching a free preview of ChatGPT, its new AI chatbot based on GPT-3.5. According to OpenAI, the preview received over a million signups within the first five days.[98] According to anonymous sources cited by Reuters in December 2022, OpenAI Global, LLC was projecting $200 million of revenue in 2023 and $1 billion in revenue in 2024.[99]
Percentage of US adults who have ever used ChatGPT, according to Pew Research. As of March 2025, 58% of those under 30 have used the chatbot.[100]
The emergence of DeepSeek has led major Chinese tech firms such as Baidu and others to embrace an open-source strategy, intensifying competition with OpenAI. Altman acknowledged the uncertainty regarding U.S. government approval for AI cooperation with China, but emphasized the importance of fostering dialogue between technological leaders in both nations.[106] In response to DeepSeek, OpenAI overhauled its security operations to better guard against industrial espionage, particularly amid allegations that DeepSeek had improperly copied OpenAI's distillation techniques.[107]
On Friday, November 17, 2023, OpenAI's board, composed of researcher Helen Toner, Quora CEO Adam D'Angelo, AI governance advocate Tasha McCauley, and most prominently in the firing, OpenAI co-founder and chief scientist Ilya Sutskever, announced that they had made the decision to remove Altman as CEO and Greg Brockman from the board, both of whom were co-founders.[108] The announcement cited that Altman "was not consistently candid in his communications" in a public announcement on the OpenAI blog.[109][108] In response, Brockman resigned from his role as President of OpenAI.[110] The day after Altman was removed, the board discussed bringing him back to OpenAI.[111]
On November 20, Microsoft CEO Satya Nadella announced that Altman would be joining Microsoft to lead a new advanced AI research team.[112] Two days later, OpenAI employees published an open letter to the board threatening to leave OpenAI and join Microsoft, where all employees had been promised jobs, unless all board members step down and reinstate Altman as CEO. 505 employees initially signed, which later grew to over 700 out of 770 total employees.[113] This included Ilya Sutskever, who had previously advocated for firing Altman, but now had apologized stating on Twitter, "I regret my participation in the board's actions." Late in the night on November 20, OpenAI announced that they had reached an "agreement in principle" for Altman to return as CEO and Brockman to return as president.[114][115] On November 21, 2023, after continued negotiations, Altman and Brockman returned to the company in their prior roles along with a reconstructed board made up of new members Bret Taylor (as chairman) and Lawrence Summers, with D'Angelo remaining.[116]
In May 2024, after OpenAI's non-disparagement agreements were exposed, Altman was accused of lying when claiming to have been unaware of the equity cancellation provision for departing employees that don't sign the agreement.[117] Also in May, former board member Helen Toner explained the board's rationale for firing Altman in November 2023. She stated that Altman had withheld information, for example about the release of ChatGPT and his ownership of OpenAI's startup fund. She also alleged that two executives in OpenAI had reported to the board "psychological abuse" from Altman, and provided screenshots and documentation to support their claims. She said that many employees feared retaliation if they didn't support Altman, and that when Altman was Loopt's CEO, the management team asked twice to fire him for what they called "deceptive and chaotic behavior".[118][119]
Altman had contemplated running for governor of California in the 2018 election, but later decided not to enter.[120] In 2018, Altman announced "the United Slate", a political project to improve U.S. housing and healthcare policy.[121] In 2019, Altman held a fundraiser at his home in San Francisco for 2020 Democratic presidential candidate and fellow tech entrepreneur Andrew Yang.[122] In May 2020, Altman donated $250,000 to American Bridge 21st Century, a super PAC supporting Democratic presidential candidate Joe Biden.[123]
Altman is a supporter of land value taxation[124] and the payment of universal basic income (UBI).[125] In 2021, he published a blog post titled "Moore's Law for Everything", which stated his belief that within ten years, AI could generate enough value to fund a UBI of $13,500 per year to every adult in the United States.[126] In 2024, he suggested a new kind of UBI called "universal basic compute" to give everyone a "slice" of ChatGPT's computing power.[125]
On November 18, 2024, San Francisco Mayor-Elect Daniel Lurie named him to his transition team.[129]
In December 2024, it was reported that Altman would donate $1 million to the Inaugural Fund for President Donald Trump.[130]
Altman hosted a fundraiser in San Francisco on March 20, 2025, for Senator Mark Warner, a Democrat up for re-election in 2026 in Virginia.[127]
On July 4, 2025, Altman posted to X to share his political ideology. He believes in "techno-capitalism" and finds himself increasingly "politically homeless". He criticized the Democratic Party for no longer encouraging a "culture of innovation and entrepreneurship".[131]
Altman is gay, and first disclosed his sexuality at the age of 17 in high school, where he spoke out after some students objected to a National Coming Out Day speaker.[3][133][134] He dated Loopt co-founder Nick Sivo for nine years. They broke up shortly after the company was acquired in 2012.[133]
Altman married engineer Oliver Mulherin in January 2024,[135] at their estate in Hawaii;[136] the pair also live in San Francisco's Russian Hill neighborhood and often spend weekends in Napa, California.[134][137] They committed to giving away most of their wealth by signing the Giving Pledge in May 2024.[138] The couple has a son, born in 2025.[139]
In January 2025, Altman's sister Ann Altman filed a lawsuit alleging sexual abuse by Altman in U.S. District Court in the Eastern District of Missouri in St. Louis. The lawsuit alleges that the abuse started when Ann Altman was aged three and Sam Altman was 12.[141] Sam Altman, along with his mother Connie and younger brothers Max and Jack, issued a joint statement denying the allegations, describing them as "utterly untrue".[142][143][144]
^Chapman, Glenn; Bachner, Michael; Magid, Jacob; Ben-David, Ricky; Schneider, Tal; Magid, Jacob; Bachner, Michael; Sharon, Jeremy (May 17, 2023). "Sam Altman: The quick, deep thinker leading OpenAI". The Times of Israel. Archived from the original on June 1, 2023. Retrieved November 24, 2023.