On Nov. 17, Silicon Valley tumbled into turmoil when Sam Altman, chief executive of the high-profile A.I. start-up OpenAI, was suddenly removed by the company’s board of directors. After a five-day roller-coaster ride that encapsulated the increasingly heated battle over the future of artificial intelligence, Mr. Altman was reinstated and a new board was created. Here is a list of players in the year’s biggest tech drama:
Sam Altman, OpenAI’s chief executive and a founder: Mr. Altman founded OpenAI as a nonprofit lab with Elon Musk and several others in 2015, while serving as the president of Y Combinator, a powerful Silicon Valley start-up incubator. He took over as chief executive in 2018, attached the lab to a for-profit company and soon raised $1 billion in funding from Microsoft.
Greg Brockman, OpenAI’s president and a founder: After dropping out of the Massachusetts Institute of Technology, Mr. Brockman was the chief technology officer at Stripe, an online payment company that Mr. Altman helped incubate. He was among OpenAI’s 12 founders, saying the lab would build A.I. that was free from the corporate pressures that drove Google and other tech giants.
Ilya Sutskever, OpenAI’s chief scientist and a founder: Dr. Sutskever was among three researchers at the University of Toronto who launched the A.I. boom in 2012 when they published a paper showing that machines could learn to identify objects in images with surprising accuracy. After joining Google, he defected to join Mr. Altman, Mr. Brockman and others in founding OpenAI.
Mira Murati, OpenAI’s chief technology officer: Ms. Murati joined OpenAI in 2018 and later became its chief technology officer. When four OpenAI board members — Dr. Sutskever, Adam D’Angelo, Helen Toner and Tasha McCauley — decided to remove Mr. Altman as chief executive, they asked Ms. Murati to briefly serve as interim chief executive.
Adam D’Angelo, OpenAI board member: As a student at Phillips Exeter Academy, he built an online music player alongside Mark Zuckerberg, the future founder of Facebook. After serving as Facebook’s chief technology officer from 2006 to 2008, he founded the question-and-answer site Quora. He joined the OpenAI board of directors in 2018 and remains chief executive of Quora.
Helen Toner, former OpenAI board member: Ms. Toner joined the board in 2021. She has ties to effective altruism, a community of people who believe that A.I. could one day destroy humanity. She is also a director of strategy at Georgetown University’s Center for Security and Emerging Technology, a think tank, where she writes about national security issues. She left the board as part of the agreement to bring Mr. Altman back to the company.
Tasha McCauley, former OpenAI board member: Ms. McCauley is an adjunct senior management scientist at the RAND Corporation, one of the country’s oldest think tanks, and serves on the British board of Effective Ventures, a federation of organizations dedicated to effective altruism. In 2015, she attended a seminal A.I. safety summit in Puerto Rico alongside Mr. Musk and others. She, too, left the OpenAI board when Mr. Altman returned.
Satya Nadella, Microsoft’s chief executive: Mr. Nadella bumped into Mr. Altman in 2018 at the Sun Valley Conference, often called “summer camp for billionaires.” In the year that followed, Mr. Nadella and Microsoft agreed to invest $1 billion in OpenAI. They have since invested an additional $12 billion.
Brian Chesky, Airbnb’s chief executive: Mr. Chesky’s company is another tech start-up that Mr. Altman helped incubate. After Mr. Altman was ousted from OpenAI — and decided that he would find a way of returning to the company — Mr. Chesky was among the many friends and colleagues who helped make it happen.
Emmett Shear, former chief executive of Twitch: Mr. Shear founded Justin.tv, yet another start-up Mr. Altman helped incubate. He later served as chief executive of Twitch, a company spun out of Justin.tv. He is among those who believe that A.I. could one day destroy humanity. Mr. Shear also briefly served as OpenAI’s interim chief executive.
Bret Taylor, new OpenAI board chairman: Mr. Taylor is the former co-chief executive of Salesforce.com and another former chief technology officer for Facebook. He was also the chair of Twitter when Mr. Musk bought it. As part of the agreement to return Mr. Altman to OpenAI, Mr. Taylor joined the OpenAI board and took over as chairman.
Lawrence H. Summers, new OpenAI board member: Mr. Summers is one of the country’s most prominent economists. He served as Treasury secretary in the Clinton administration, and has been speaking out about the potential for A.I. to displace workers. But his reputation has been damaged over the years. While serving as president of Harvard, he said women might lack an intrinsic aptitude for math and science.
Ron Conway, Silicon Valley investor: Mr. Conway is a well-known venture capitalist and longtime friend of Mr. Altman’s. With Mr. Chesky, he helped persuade Mr. Altman to push his way back into OpenAI. This week, he sent a text to Mr. Altman urging him to silence speculation about why he was removed from the OpenAI board.