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| Sam Altman | |
|---|---|
| Born | Samuel Harris Altman, April 22, 1985 (age 41), Chicago, Illinois, U.S. |
| Education | Stanford University (attended 2003-2005, did not graduate) |
| Known for | Co-founding OpenAI, leading development of ChatGPT, Loopt, Y Combinator presidency, World (formerly Worldcoin), Stargate Project |
| Title | CEO of OpenAI, Chairman of Tools for Humanity |
| Spouse | Oliver Mulherin (m. 2024) |
| Children | 1 |
| Net worth | US$2.1 billion (Forbes, December 2025)[1] |
Sam Altman (born Samuel Harris Altman; April 22, 1985) is an American entrepreneur, investor, and technology executive who is the chief executive officer and co-founder of OpenAI, the artificial intelligence company behind ChatGPT, the fastest-growing consumer application in history, which surpassed 800 million weekly active users in October 2025 and roughly 900 million by February 2026.[59][60] OpenAI, the laboratory behind ChatGPT, GPT-4, and GPT-5, was valued at $852 billion after a $122 billion funding round that closed on March 31, 2026, making it the most valuable private startup in the world.[35] Altman is also the chairman of Tools for Humanity, the company behind the World (formerly Worldcoin) biometric identity and cryptocurrency project. Before leading OpenAI, Altman was the president of Y Combinator, one of Silicon Valley's most influential startup accelerators, from 2014 to 2019.[2]
Altman has been described as one of the most influential figures of the AI boom, a characterization cemented by the explosive global adoption of ChatGPT following its launch in November 2022. His tenure at OpenAI has also been marked by significant controversy, most notably his brief firing and reinstatement by the company's board of directors in November 2023, ongoing debates about the balance between AI safety and commercial deployment, and the company's transformation from a nonprofit research lab into one of the world's most valuable technology companies. In January 2025, he stood alongside US President Donald Trump to announce the Stargate Project, a $500 billion AI infrastructure initiative.[3]
Sam Altman is the CEO and co-founder of OpenAI, the company that built ChatGPT. He co-founded OpenAI as a nonprofit research lab on December 11, 2015, became CEO of its for-profit arm in 2019, and led the company through the launch of ChatGPT on November 30, 2022, and the firm's growth to an $852 billion valuation by March 2026.[35] He was briefly fired by OpenAI's board on November 17, 2023, and reinstated five days later after roughly 745 of the company's approximately 770 employees threatened to resign.[24] Before OpenAI, he co-founded the location-sharing app Loopt in 2005 and served as president of the startup accelerator Y Combinator from 2014 to 2019.[2] Notably, until the October 2025 corporate restructuring, Altman held no equity in OpenAI and drew an annual salary of $76,001; his estimated $2.1 billion net worth (Forbes, December 2025) came almost entirely from early-stage investments in companies such as Reddit, Stripe, and Airbnb.[1]
Samuel Harris Altman was born on April 22, 1985, in Chicago, Illinois, to a Jewish American family. His mother, Connie Gibstine, is a board-certified dermatologist who has practiced in the St. Louis area for more than three decades; she earned a Bachelor of Science in biology from the University of Illinois, completed her medical degree at the University of Missouri, and finished her residency at Northwestern Medicine in Chicago. His father, Jerry Altman, was a real estate broker who worked on affordable housing and historic preservation projects in St. Louis; he died unexpectedly of a heart attack in 2018. Sam is the eldest of four siblings: brothers Jack and Max, and a sister, Ann.[4]
In 1989, when Sam was four, the Altman family moved from Chicago to Clayton, a suburb of St. Louis, Missouri. He received his first computer, an Apple Macintosh, at the age of eight and quickly began coding, disassembling, and reassembling hardware. Family dinners were a nightly ritual, supplemented by table tennis, billiards, and charades. Altman has described frequent affirmations of love and capability from his parents as formative.[5]
Altman attended John Burroughs School, an elite preparatory school in Ladue, Missouri, graduating in the class of 2003. During high school, he came out as gay. After a Christian student group boycotted a planned assembly on sexuality, Altman addressed the entire school assembly, disclosed his orientation, and asked whether John Burroughs wanted to be a repressive place or one open to different ideas. He encouraged teachers to display "Safe Space" placards in classrooms in support of LGBTQ students; his college counselor later said the moment changed the school. The episode has often been cited as an early indication of Altman's appetite for confrontation and public advocacy.[6]
In 2003, Altman enrolled at Stanford University to study computer science, joining the school as a freshman at the age of 18. He worked in Stanford's artificial intelligence lab during his undergraduate years and later remarked that he learned more playing poker with classmates than from his lecture courses.[7] He left Stanford in 2005 after two years and without earning a bachelor's degree. His departure was driven less by dissatisfaction than by an opportunity he could not pass up: Paul Graham's newly launched Y Combinator program, which actively encouraged technically strong students to build companies rather than finish their degrees.
In the spring of 2005, at the age of 19, Altman co-founded Loopt, a location-based social networking mobile application, with Nick Sivo (a Stanford classmate and Altman's then-boyfriend) and Alok Deshpande. They later added two of Altman's childhood friends, Rick and Tom Pernikoff, to help build early prototypes. Loopt was one of eight companies in Y Combinator's inaugural Summer Founders Program, receiving $6,000 per founder along with mentorship from Paul Graham, Jessica Livingston, Robert Morris, and Trevor Blackwell. Y Combinator had selected the eight teams from roughly 225 applications.[8]
As CEO, Altman raised more than $30 million in venture capital for Loopt. The initial $5 million investment came from Patrick Chung of Xfund and New Enterprise Associates, followed by investments from Sequoia Capital and Y Combinator. Loopt let users share their real-time location with friends through their mobile phones, a concept that ran ahead of the smartphone wave. At Apple's Worldwide Developers Conference in June 2008, a 23-year-old Altman demonstrated Loopt on stage as one of the launch applications for the new iPhone App Store; the iOS app shipped to US App Store customers on July 11, 2008.[9]
Despite the funding, the WWDC stage time, and partnerships with carriers such as Sprint and Verizon, Loopt never achieved significant user traction. In March 2012, the company was acquired by Green Dot Corporation, a financial services firm, for $43.4 million. The acquisition returned capital to investors but was widely viewed as a modest outcome relative to the company's ambitions and the amount of venture capital raised. Altman's share, before tax, was approximately $5 million.[10]
| Loopt key facts |
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| Founded |
| Founders |
| Product |
| Total funding raised |
| iOS App Store launch |
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In April 2012, shortly after the sale of Loopt, Altman co-founded Hydrazine Capital, a venture fund, with his brother Jack Altman. The initial $21 million fund was anchored by Peter Thiel and seeded in part with proceeds from the Loopt sale. Altman invested roughly 75% of Hydrazine's capital in Y Combinator companies, including early checks into Reddit, Stripe, Instacart, Pinterest, Asana, and Airbnb. He later raised additional Hydrazine funds, including a 2018 vehicle that received a $75 million commitment from the University of Michigan.[11]
In 2011, Altman joined Y Combinator as a part-time partner. In February 2014, Paul Graham and Jessica Livingston personally selected him to succeed Graham as president. Graham later explained the choice by saying "YC needs to get bigger, and I am not really much of a manager. Sam Altman is."[12]
During his tenure (February 2014 to March 2019), Altman oversaw a significant expansion of Y Combinator. By the time he stepped down, the accelerator had funded approximately 1,900 companies. Notable companies that went through Y Combinator under his leadership or shortly before include Airbnb, DoorDash, Instacart, Reddit, Stripe, and Twitch. Standard YC terms during his presidency offered startups $120,000 (later raised to $500,000 of "tooling money") in exchange for 7% equity, along with three months of intensive mentorship and access to YC's network of alumni and investors.[13] Altman also launched YC Continuity, an expansion-stage fund, and YC Research, a nonprofit research lab that incubated the early OpenAI team in 2015.
Altman pursued a number of side projects during his time at Y Combinator. He launched the YC Fellowship program for very early-stage founders, co-authored an essay series on startups, and in 2017 briefly explored running for governor of California in the 2018 election before declining to enter the race.[14] He gave up his Y Combinator board roles in March 2019 to focus on OpenAI full time; Geoff Ralston, a longtime YC partner, was promoted to president of YC, and Altman briefly served as chairman before transitioning to an advisor role two months later.[15]
On December 11, 2015, Altman co-founded OpenAI as a nonprofit artificial intelligence research organization alongside Elon Musk, Greg Brockman, Ilya Sutskever, Andrej Karpathy, John Schulman, Wojciech Zaremba, and several other researchers. The venture was announced with $1 billion in pledged funding from Altman, Musk, Reid Hoffman, Peter Thiel, Jessica Livingston, Amazon Web Services, Infosys, and YC Research, with Altman and Musk serving as co-chairs.[16]
The stated mission of OpenAI was to ensure that artificial general intelligence (AGI) benefits all of humanity. Altman and Musk both cited concerns about AI safety as a motivating factor, arguing that the development of powerful AI systems should not be concentrated in the hands of a single corporation, particularly Google, which had acquired DeepMind in 2014. Sutskever was hired away from Google Brain to serve as chief scientist, and Brockman, formerly chief technology officer of Stripe, became chief technology officer.
Elon Musk departed OpenAI's board in February 2018, citing a potential conflict of interest with Tesla's own AI research efforts. Musk later became a vocal critic of OpenAI's direction, particularly after the organization's shift toward a for-profit structure. Internal emails released during litigation in 2024 and 2026 showed that Musk had repeatedly pushed to fold OpenAI into Tesla or to take operational control of the organization before his departure, options the other founders rejected.[17]
In March 2019, OpenAI created a "capped-profit" subsidiary, OpenAI LP, in which investors' returns were capped at 100 times their investment. The original nonprofit board retained oversight and control. Altman took on the role of CEO of the new entity, stepping down from his position at Y Combinator the same month to focus on OpenAI full time.[18]
The restructuring was controversial. Critics argued that it represented a departure from OpenAI's founding mission as an open, nonprofit research organization. Supporters countered that the capital requirements of training frontier AI models made a purely nonprofit structure unsustainable. Microsoft invested $1 billion in OpenAI in July 2019, becoming the company's primary cloud partner and a close commercial ally. In June 2020, OpenAI's first major commercial product, the GPT-3 API, launched in private beta, generating the early revenue that funded subsequent model training runs.[19]
OpenAI launched ChatGPT on November 30, 2022, and the product became one of the fastest-growing consumer applications in history, reaching an estimated 100 million users within two months. According to a UBS study, ChatGPT hit roughly 100 million monthly users in January 2023, about two months after launch, a faster ramp than TikTok (about nine months) or Instagram (about two and a half years) took to reach the same milestone; UBS analysts wrote that "In 20 years following the internet space, we cannot recall a faster ramp in a consumer internet app."[61] Built on the GPT-3.5 architecture and later upgraded to GPT-4 (released March 14, 2023), ChatGPT demonstrated the power of large language models to a mass audience and triggered a global wave of investment, competition, and public debate about the implications of advanced AI.[20]
Altman became the public face of this AI boom. In May 2023 he undertook a European leg of what reporters dubbed his "world tour," meeting French President Emmanuel Macron, European Commission President Ursula von der Leyen, Spanish Prime Minister Pedro Sanchez, and Polish Prime Minister Mateusz Morawiecki. The Asia and Middle East leg in June 2023 included stops in Israel, Jordan, Qatar, the United Arab Emirates, India, South Korea, Japan, Singapore, Indonesia, and Australia, with meetings with Indian Prime Minister Narendra Modi, South Korean President Yoon Suk-yeol, Israeli President Isaac Herzog, and others.[21]
On May 16, 2023, Altman testified before the US Senate Judiciary Subcommittee on Privacy, Technology, and the Law in a hearing titled "Oversight of A.I.: Rules for Artificial Intelligence." He was one of three witnesses, alongside IBM's Christina Montgomery and NYU professor Gary Marcus. Altman expressed support for government regulation, proposed a new federal agency that could license frontier AI development above a capability threshold, supported pre-deployment testing and independent audits, and offered the International Atomic Energy Agency as a model for international coordination. Senator Richard Blumenthal opened the hearing by playing a deepfake audio clip of his own voice generated by AI.[22]
On November 17, 2023, at approximately noon Pacific time, OpenAI's board of directors abruptly fired Altman as CEO. Altman was informed via Google Meet roughly five to ten minutes before the public announcement, while attending the Las Vegas Grand Prix. The board issued a brief statement saying it had lost "confidence in his ability to continue leading OpenAI" and that he had not been "consistently candid in his communications with the board." Chief Technology Officer Mira Murati was named interim CEO. Greg Brockman, who had been removed as board chairman but offered a continuing role, resigned in protest hours later.[23]
The four board members who voted to remove Altman were chief scientist Ilya Sutskever, Quora co-founder and CEO Adam D'Angelo, entrepreneur Tasha McCauley, and Helen Toner, strategy director for the Center for Security and Emerging Technology. Reid Hoffman, Shivon Zilis, and Will Hurd had previously left the board, leaving the board with only six seats and Altman and Brockman in the minority. The firing triggered one of the most dramatic episodes in recent Silicon Valley history. The events unfolded over five chaotic days:
| Date | Event |
|---|---|
| November 17, 2023 | Board fires Altman; Mira Murati named interim CEO; Greg Brockman resigns as board chairman and then leaves the company; research director Jakub Pachocki and several senior researchers resign |
| November 18, 2023 | Reports emerge that investors are pushing for Altman's reinstatement; Altman visits OpenAI offices wearing a guest badge ("first and last time I ever wear one of these") |
| November 19, 2023 | Board appoints Emmett Shear (former Twitch CEO) as interim CEO late at night; Microsoft CEO Satya Nadella announces Altman and Brockman will join Microsoft to lead a new AI research team |
| November 20, 2023 | Approximately 745 of OpenAI's roughly 770 employees sign a letter threatening to follow Altman to Microsoft unless the board resigns; Ilya Sutskever signs the letter and posts "I deeply regret my participation in the board's actions"; OpenAI announces "agreement in principle" for Altman to return |
| November 21, 2023 | Altman is reinstated as CEO with a new initial board consisting of Bret Taylor (chairman), Lawrence Summers, and Adam D'Angelo; Altman and Brockman agree not to retake board seats pending an internal investigation |
| November 22, 2023 | OpenAI formally announces Altman's return and new initial board composition[24] |
The precise reasons behind the board's decision have been the subject of extensive reporting. According to later disclosures by Toner and McCauley, the board had been concerned about Altman withholding information (for example, the board learned about the release of ChatGPT on Twitter rather than in advance, and Altman had not disclosed his ownership of the OpenAI Startup Fund), providing inaccurate information about the company's formal safety processes, and what two executives described as a pattern of manipulative behavior and "psychological abuse," documented in screenshots provided to the board.[25]
The board retained the law firm WilmerHale to conduct an external review. On March 8, 2024, OpenAI announced the conclusion of that review and the reconstitution of the board with three new members: Sue Desmond-Hellmann (former CEO of the Bill and Melinda Gates Foundation), Nicole Seligman (former Sony general counsel), and Fidji Simo (then CEO and chair of Instacart). Altman rejoined the board the same day. WilmerHale concluded that Altman's prior conduct "did not mandate removal" and that the firing was the result of a "breakdown in the relationship and loss of trust" rather than safety lapses or product issues.[26]
Under Altman's continued leadership, OpenAI has released a rapid succession of models and products:
| Product / model | Release date | Key features |
|---|---|---|
| GPT-4 Turbo | November 6, 2023 | 128k context window, lower pricing, improved instruction following |
| Sora (preview) | February 15, 2024 | First public preview of OpenAI's text-to-video model |
| GPT-4o | May 13, 2024 | Omni model with native multimodal capabilities (text, vision, audio) |
| GPT-4o mini | July 18, 2024 | Lower-cost variant of GPT-4o |
| o1 | September 2024 (preview), December 2024 (full) | Reasoning model that "thinks" before answering |
| Sora (full) | December 2024 | First-generation text-to-video model launched for ChatGPT Plus and Pro users in US and Canada |
| o3 | December 2024 (preview), April 2025 (general availability) | Next-generation reasoning model; scored 87.5% on ARC-AGI benchmark |
| GPT-4.5 | February 2025 | Final non-chain-of-thought model |
| GPT-5 | August 7, 2025 | Flagship model unifying reasoning and generation; improved coding, reasoning, medical applications |
| Sora 2 | September 2025 | Successor video model with improved physics and audio |
| GPT-5.2 | December 2025 | Improved reasoning capabilities |
| GPT-5.4 | March 2026 | Frontier model for professional work and long-running agents |
Altman described GPT-5 as a "unification" of OpenAI's separate model lines, merging the GPT series (optimized for broad capability) with the o-series (optimized for reasoning) into a single coherent system. After the launch, he publicly acknowledged that OpenAI had "totally screwed up" parts of the GPT-5 rollout when the company initially removed older models from ChatGPT; OpenAI restored GPT-4o as a user-selectable option within days.[27]
The scale of adoption grew in parallel with the product lineup. At OpenAI's third annual DevDay on October 6, 2025, Altman announced that ChatGPT had reached 800 million weekly active users, telling developers: "More than 800 million people use ChatGPT every week, and we process over 6 billion tokens per minute on the API," and adding that "today, 4 million developers have built with OpenAI."[59] By February 2026, OpenAI reported that ChatGPT's weekly active user base had grown to roughly 900 million.[60]
The leadership team turned over substantially during this period. Mira Murati, who had served as chief technology officer since 2018 and as interim CEO during the November 2023 crisis, left OpenAI in September 2024 to found her own startup, Thinking Machines Lab. Jakub Pachocki took over as chief scientist after Sutskever's May 2024 departure, and Mark Chen was elevated to senior vice president of research.[28]
On October 28, 2025, OpenAI completed its transformation from a hybrid nonprofit/capped-profit structure into a Public Benefit Corporation (PBC), ending years of debate about the company's governance. The restructuring required and obtained approval from the attorneys general of California and Delaware. It created two distinct entities: the OpenAI Foundation (the reconstituted nonprofit, which retained majority governance control through special voting rights, including authority to appoint and remove all directors of the PBC) and OpenAI Group PBC (the for-profit operating entity).[29]
The OpenAI Foundation holds an approximately 26% stake in OpenAI Group, valued at roughly $130 billion at the time of the deal, plus a performance-based warrant entitling it to additional equity if OpenAI Group's share price increases more than tenfold over 15 years. Microsoft's stake was set at approximately 27%, worth about $135 billion, with employees and other investors holding the remaining 47%. Microsoft retained access to OpenAI's pre-AGI technology through 2032, including any models that reach the AGI milestone, and OpenAI committed to purchasing an incremental $250 billion of Azure services.[30]
Under the new structure, Altman received equity in OpenAI for the first time. Previously, he had famously held no equity in the company and earned an annual salary of $76,001. The restructuring was a precondition for OpenAI's path toward a potential initial public offering and for the full release of capital pledged in the March 2025 SoftBank-led round.[29]
Alongside the PBC conversion, OpenAI and Microsoft signed a substantially renegotiated partnership on October 28, 2025. Microsoft's equity stake decreased from 32.5% under the prior capped-profit agreement to approximately 27% in the new entity. In a major concession, Microsoft relinquished its exclusivity as OpenAI's cloud provider, although OpenAI committed to purchasing an incremental $250 billion in Azure services. Microsoft retained exclusive rights to OpenAI's models and intellectual property, plus API access, until AGI is achieved, with that threshold now to be verified by an independent expert panel rather than declared by OpenAI's board alone.[31]
In April 2026, the two companies further amended the partnership, capping the revenue-share payments OpenAI owes Microsoft and formally ending Azure exclusivity while keeping Microsoft as the primary cloud partner. One analysis estimated the renegotiated terms could save OpenAI roughly $97 billion in payments through 2030.[32]
OpenAI's valuation has grown at an extraordinary pace:
| Date | Valuation | Funding round / event |
|---|---|---|
| January 2024 | $86 billion | Secondary market transactions |
| October 2024 | $157 billion | $6.6 billion funding round |
| March 2025 | $300 billion | $40 billion round led by SoftBank (with Magnetar, Coatue, Founders Fund, Altimeter) |
| October 2025 | $500 billion | $6.6 billion employee tender offer |
| March 2026 | $852 billion | $122 billion round (Amazon up to $50B, Nvidia $30B, SoftBank $30B) |
The March 2025 round, announced on March 31, 2025, was the largest private funding round on record at the time. SoftBank committed $30 billion of the $40 billion and structured the deal in two tranches: $10 billion in the first phase (with $2.5 billion from a syndicate of co-investors) and $30 billion in the second (with another $7.5 billion from the syndicate). According to the Wall Street Journal, full release of SoftBank's capital was contingent on OpenAI completing its for-profit restructuring by the end of 2025, a condition that was met with the October 2025 PBC conversion.[33]
The $122 billion round that closed on March 31, 2026, surpassed it as the largest private funding round to date, valuing OpenAI at $852 billion. Amazon agreed to invest $50 billion (with $35 billion of that contingent on OpenAI going public or reaching AGI), while Nvidia and SoftBank each committed $30 billion; at the time of the round OpenAI said it was generating roughly $2 billion in revenue per month.[35]
OpenAI's annual recurring revenue (ARR) grew from approximately $2 billion in 2023 to roughly $6 billion in 2024 and topped $20 billion in 2025, reaching an estimated $25 billion annualized rate by February 2026 on roughly $2 billion in monthly revenue.[34] OpenAI is targeting an IPO in the second half of 2026, with the public offering expected to value the company at over $1 trillion.[35]
On January 21, 2025, the day after his second inauguration, US President Donald Trump appeared at the White House alongside Altman, Oracle co-founder Larry Ellison, and SoftBank CEO Masayoshi Son to announce the Stargate Project, a joint venture committing up to $500 billion over four years to build AI data center infrastructure in the United States, with $100 billion deployed immediately. Initial equity owners include SoftBank and OpenAI (each holding approximately 40%) plus Oracle and MGX (each holding approximately 7%); SoftBank initially committed $19 billion and OpenAI matched that figure, while Oracle and MGX each pledged $7 billion. Masayoshi Son was named chairman of the venture and OpenAI took operational responsibility; the announced technology partners were Arm, Microsoft, Nvidia, Oracle, and OpenAI.[36]
The flagship Stargate campus is located in Abilene, Texas, and runs on Oracle Cloud Infrastructure. On September 23, 2025, OpenAI announced five additional Stargate sites, bringing planned capacity to nearly seven gigawatts and over $400 billion in committed investment over three years, on a path to the full $500 billion, 10-gigawatt commitment announced in January. The program represents the centerpiece of Altman's argument that frontier AI requires an unprecedented buildout of compute, energy, and physical infrastructure, and that the buildout must happen in the United States to retain a strategic edge over China.[37] The announcement publicly elevated Altman above Elon Musk, who had become a senior White House adviser, and prompted a public spat between the two on X.[38]
Altman is the chairman and co-founder of Tools for Humanity, the company behind the World project (formerly known as Worldcoin). He co-founded the company in 2019 with Alex Blania (now CEO) and Max Novendstern. The project aims to create a global identity and financial network by providing every person on Earth with a verified digital identity (World ID) using biometric iris scanning through a device called the Orb. Altman has argued that iris codes carry more entropy than fingerprints or facial geometry and are less prone to change.[39]
The World project launched publicly in July 2023 and was rebranded from Worldcoin to World in 2024. It combines three components: World ID (a privacy-preserving digital identity built on zero-knowledge proofs), a cryptocurrency token (WLD) distributed to verified humans, and the World App, a digital wallet.
| World project key milestones |
|---|
| Founded |
| Public launch |
| Rebranded |
| US launch |
| Users |
| Super app launch |
| Partnerships |
The project has faced significant regulatory challenges. Multiple countries have investigated or restricted World's operations over privacy concerns related to biometric data collection. Data protection regulators in Bavaria, Brazil, Kenya, South Korea, Spain, and elsewhere have opened investigations or imposed fines. In October 2025, the Philippines' National Privacy Commission issued a cease and desist order against Tools for Humanity for violations of the Data Privacy Act, directing the company to stop all collection and processing of personal data, including iris scans, in the Philippines.[40]
Altman has argued that World ID will become increasingly important as AI-generated content makes it harder to distinguish between real humans and bots online, framing the project as a necessary piece of infrastructure for the AI age.
Altman has been the principal financial backer of Helion Energy, a fusion energy startup, since joining as board chairman in 2015, shortly before he co-founded OpenAI. He made his first investment of $9.5 million in Helion in 2015 after the company went through Y Combinator in 2014. In November 2021, he personally invested $375 million in Helion's $500 million Series E funding round, his largest single startup investment, later remarking that he had "basically just took all my liquid net worth and put it into" Helion and Retro Biosciences. As of late 2025, Altman owned roughly a third of Helion, a stake valued at approximately $1.65 billion.[41]
Helion was founded in 2013 by David Kirtley (CEO), John Slough, George Votroubek, and Chris Pihl, and its approach uses pulsed magnetic compression of a field-reversed configuration plasma to attempt aneutronic fusion using deuterium and helium-3 fuel. In May 2023, Helion agreed to sell electricity from its first commercial fusion plant, under construction near Everett in central Washington state, to Microsoft starting in 2028, a power purchase agreement of 50 megawatts or more after a one-year ramp. In February 2026, Helion announced it had achieved a record plasma temperature of 150 million degrees Celsius, a milestone toward grid-scale fusion. In March 2026, Altman stepped down as Helion's board chairman after OpenAI entered talks to purchase fusion power from the company; he recused himself from the negotiations to manage the conflict of interest.[42]
Altman was also the founding chairman and largest individual investor in Oklo, an advanced nuclear fission company developing small modular reactors. Oklo went through Y Combinator in 2014 while Altman was president, and he invested in the company and joined as chairman in 2015. In July 2023, he announced he would take Oklo public via AltC Acquisition Corp., a special purpose acquisition company he had co-founded. The merger closed in May 2024, and Oklo (ticker: OKLO) began trading on the New York Stock Exchange on May 10, 2024; it received more than $306 million in gross proceeds and traded down 54% on debut. In April 2025, Altman stepped down as chairman of Oklo, citing the conflict of interest as Oklo pursued commercial partnerships with AI companies for compute power.[43]
In 2022, Altman provided the entire $180 million seed funding for Retro Biosciences, a longevity-focused biotechnology company seeking to add 10 years to the healthy human lifespan through epigenetic reprogramming, cellular reprogramming, and autophagy-based therapies. The investment was among the largest ever made by an individual into a longevity startup.[44]
Retro Biosciences has worked with OpenAI on an AI model (GPT-4b micro) designed to engineer protein variants of the Yamanaka factors used in cellular reprogramming. In January 2025, the company began raising an additional $1 billion round at a target valuation of up to $5 billion to fund clinical development.[45]
Altman testified before the US Senate Judiciary Subcommittee on Privacy, Technology, and the Law on May 16, 2023, in a hearing titled "Oversight of A.I.: Rules for Artificial Intelligence." He was one of three AI experts who testified, alongside IBM's Christina Montgomery and NYU professor Gary Marcus. During the hearing, Altman expressed support for government regulation of AI, proposed the creation of a new federal regulatory agency, and suggested a licensing and testing regime for frontier AI models above a capability threshold. He also supported independent audits, content provenance standards, and the creation of an international body modeled on the International Atomic Energy Agency. Senator Richard Blumenthal opened the hearing by playing a deepfake audio clip of his own voice generated by AI, underscoring the urgency of the regulatory questions at hand.[22]
On March 16, 2021, more than 20 months before ChatGPT's launch, Altman published an essay titled "Moore's Law for Everything" on a personal site. The essay argued that software systems capable of thinking and learning would shift economic value from labor to capital and that the price of nearly every form of work would decline rapidly, in a pattern resembling the historical decline in compute costs. To redistribute the gains, Altman proposed an "American Equity Fund" funded by a 2.5% annual tax on the market value of companies above a certain size and on privately held land; the proceeds would be paid as an equal cash dividend to every adult citizen. Critics found the essay both prescient about AI's economic impact and politically naive about implementation; supporters cited it as evidence that Altman had been thinking systematically about distributional consequences before the GPT-4 era.[46]
In a January 6, 2025 personal blog post titled "Reflections," Altman wrote that OpenAI is "now confident we know how to build AGI as we have traditionally understood it" and that "we are beginning to turn our aim beyond that, to superintelligence in the true sense of the word." In a follow-up June 2025 post called "The Gentle Singularity," he wrote: "We are past the event horizon; the takeoff has started. Humanity is close to building digital superintelligence." Altman has repeatedly speculated that superintelligence could arrive "in a few thousand days." OpenAI's official framework distinguishes five levels of AI capability, of which the firm has publicly placed itself at Level 2 (reasoners) with Level 3 (agents) emerging.[47]
In 2023, Altman undertook a widely publicized world tour, meeting with leaders in Europe, the Middle East, Asia, and Africa. The tour served both as a diplomatic effort to shape global AI policy and as a commercial initiative to build relationships in key markets. He met with heads of state including French President Emmanuel Macron, EU Commission President Ursula von der Leyen, Spanish Prime Minister Pedro Sanchez, Indian Prime Minister Narendra Modi, South Korean President Yoon Suk-yeol, Israeli President Isaac Herzog, and Nigerian President Bola Tinubu, among others. In early 2025, Altman returned to Asia for a follow-up tour, widely interpreted as a response to the rise of the Chinese model lab DeepSeek and to support Stargate-style infrastructure deals abroad.[21]
Altman donated almost exclusively to Democratic candidates and causes between 2013 and 2024. He gave $100,000 to the Biden Victory Fund in 2020 and another $200,000 in 2023. In 2016, he wrote a public endorsement of Hillary Clinton, his first ever presidential endorsement. Federal records show only one Republican on his donation history (a 2018 contribution to former North Carolina congressman Patrick McHenry). In December 2024, Altman pledged $1 million in personal funds to Donald Trump's presidential inaugural fund, framing the donation as personal rather than corporate. Democratic senators Elizabeth Warren and Michael Bennet sent a letter questioning the contribution; Altman publicly responded that the contribution was personal and that "President Trump will lead our country into the age of AI, and I am eager to support his efforts to ensure America stays ahead."[48]
In 2023, Altman was named one of Time magazine's 100 most influential people. In 2025, Altman was named among the "Architects of AI" as part of Time magazine's recognition of the AI industry, reflecting his central role in the public emergence of generative AI.[49]
Altman's leadership style has been the subject of both admiration and sharp criticism. Supporters credit him with the vision and drive that turned OpenAI from a small nonprofit into the most influential AI company in the world. Critics have raised concerns about his management practices, his accumulation of power, and the tension between OpenAI's stated safety mission and its commercial ambitions.
The departure of several senior safety researchers from OpenAI has fueled criticism that the company under Altman's leadership has prioritized product development over safety research. In May 2024, Jan Leike, co-lead of OpenAI's Superalignment team, resigned and joined Anthropic. In his departure message, Leike accused the company of letting "safety culture and processes take a back seat to shiny products" and said the team had been "sailing against the wind" for months, struggling to access the computing resources needed for safety research despite OpenAI's promise to dedicate a fifth of its compute to the effort. The Superalignment team was effectively dissolved.[50]
Ilya Sutskever, OpenAI's co-founder and former chief scientist, who was a central figure in the November 2023 board crisis, also departed the company in May 2024 to found Safe Superintelligence Inc. (SSI), a startup focused exclusively on AI safety research without an intermediate commercial product. By mid-2025 SSI had raised more than $5 billion at a $32 billion valuation.[51] Mira Murati, former CTO, departed in September 2024 to found Thinking Machines Lab, taking several senior research and product staff with her.
Critics have argued that the events of November 2023 exposed a fundamental weakness in OpenAI's governance structure: the nonprofit board, designed to serve as a check on the company's commercial ambitions, was unable to withstand the pressure from investors, employees, and commercial partners when it attempted to exercise its oversight authority. The reconstituted board, anchored by Bret Taylor and Larry Summers, was widely seen as more aligned with Altman's vision and less likely to challenge his leadership.
In a May 2024 op-ed in The Economist, former board members Helen Toner and Tasha McCauley accused Altman of "lying" and engaging in "psychological abuse" of employees, asserting that "self-governance cannot reliably withstand the pressure of profit incentives" and calling on governments to regulate frontier AI directly. A June 2025 dossier titled "The OpenAI Files," compiled from interviews with current and former employees, reiterated similar concerns and added new allegations about safety process shortcuts.[52]
Former chief technology officer Mira Murati reportedly told staff in 2023 that she did not feel comfortable with Altman leading the company to AGI. Ilya Sutskever expressed similar reservations, reportedly saying "I don't think Sam is the guy who should have the finger on the button for AGI." Dario and Daniela Amodei, who left OpenAI in 2021 to found Anthropic, reportedly described Altman's tactics as "gaslighting" and "psychological abuse."[52]
In February 2024, Elon Musk sued Altman, Greg Brockman, and OpenAI in California state court, alleging breach of contract and unjust enrichment based on the company's pivot toward a for-profit structure. Musk later refiled in federal court adding additional claims, including under the federal Racketeer Influenced and Corrupt Organizations Act. The two-week trial began in April 2026 in Oakland, California, with extensive evidence including private emails, text messages, internal meeting notes, and Brockman's personal diaries. On May 18, 2026, a jury returned a verdict that Musk's claims were time-barred by the statute of limitations, ending the principal lawsuit; appeals are expected.[53]
In January 2025, Altman's sister Ann Altman filed a lawsuit in the US District Court for the Eastern District of Missouri alleging sexual abuse by Sam Altman, claiming the abuse started when she was three years old and Sam was twelve, and continued through 2006. Sam Altman, along with his mother Connie and brothers Max and Jack, issued a joint statement calling the allegations "utterly untrue" and noting that the family had provided Ann with monthly financial support, paid her rent and bills, and attempted to arrange medical care for her. Ann Altman had publicly made similar allegations on social media in earlier years; the 2025 filing was her first formal lawsuit. The case was refiled in April 2026 after procedural dismissals and remains pending.[54]
Altman came out as gay during high school. He married Oliver Mulherin, an Australian software engineer and graduate of the University of Melbourne, in an intimate seaside ceremony near his Hawaii residence on January 10, 2024; his brother Jack officiated. The couple had been in a relationship for several years and were first publicly seen together at a White House dinner in 2023. In February 2025, Altman announced the birth of their first child, a son carried by a surrogate; the baby arrived prematurely and spent time in a neonatal intensive care unit before going home. Altman has described early parenthood as "the best thing I've ever done" and as a source of new urgency on AI safety questions.[55]
Altman is a vegetarian and a self-described prepper. He has spoken publicly about his preparations for civilizational disruptions, including stockpiling supplies, owning firearms, and maintaining a remote property in Northern California along with a Hawaii residence and a San Francisco home. He has also been open about his interest in life extension and has invested in several longevity-related startups, most prominently Retro Biosciences.[56]
In May 2024, Altman and Mulherin signed The Giving Pledge, committing to give away the majority of their wealth during their lifetimes or in their wills. Their pledge letter, dated May 18, 2024, said they intend "to focus our giving on supporting technology that helps create abundance for people, so that they can then build the scaffolding even higher."[57]
In April 2026, Altman's San Francisco home was attacked when an individual threw an incendiary device at the building; the suspect was arrested at the scene. The incident prompted Altman to share a rare photograph of his son, with whom his husband was at home at the time.
As of December 2025, Forbes estimated Altman's net worth at approximately $2.1 billion.[1] Notably, this wealth was not derived from OpenAI, in which Altman held no equity until the October 2025 PBC restructuring. Instead, the bulk of his fortune comes from early-stage investments in companies including Reddit, Uber, Asana, Airbnb, Stripe, Instacart, and Pinterest, as well as venture capital investments made through Hydrazine Capital and other vehicles. He also holds significant real estate, land, and energy assets.[1]
His Reddit position, accumulated through Series B participation in 2014, Series C participation in 2017, and later financing rounds totaling roughly $60 million in 2021, amounted to an approximately 8.7% pre-IPO stake (later 7.6% post-IPO) worth more than $1 billion by late 2024 after a post-earnings rally. Reddit's S-1 filing identified Altman as the third-largest shareholder ahead of the company's IPO.[58] Altman served on Reddit's board of directors for seven years until 2022. His annual salary as CEO of OpenAI has been reported as $76,001. Following the October 2025 restructuring, he received equity in OpenAI for the first time, which, depending on the company's eventual public market valuation, could substantially increase his net worth.[29]
| Source of wealth | Details |
|---|---|
| ~7.6% post-IPO stake; over $1 billion peak value (late 2024) | |
| Early-stage investments | Uber, Airbnb, Asana, Stripe, Instacart, Pinterest, and others |
| Helion Energy | Board chairman 2015-2026; $375 million personal investment (2021); ~1/3 ownership |
| Retro Biosciences | $180 million seed; longevity biotechnology |
| Oklo | Founding chairman 2015-2025; took company public via SPAC May 2024 |
| Hydrazine Capital | Venture fund co-founded with brother Jack Altman in 2012 |
| Real estate | Significant land and property holdings in California, Hawaii |
| OpenAI equity | Received as part of October 2025 PBC restructuring |
| Tools for Humanity | Chairman; value tied to World/WLD token and company equity |
| Salary (OpenAI) | $76,001 per year |