Sam Altman, one of the most prominent figures in the world of artificial intelligence, is being forced out of OpenAI — the company behind ChatGPT that he helped to create — after the board said it had lost confidence in him as a leader.

Chief Technology Officer Mira Murati will serve as OpenAI’s interim chief executive officer.

“Mr. Altman’s departure follows a deliberative review process by the board, which concluded that he was not consistently candid in his communications with the board, hindering its ability to exercise its responsibilities,” the company said in a statement. “The board no longer has confidence in his ability to continue leading OpenAI.”

OpenAI’s introduction of ChatGPT to the world turned 38-year-old Altman into an instant celebrity, winning him an audience with world leaders including US President Joe Biden and UK Prime Minister Rishi Sunak. He is an outspoken figure in the AI community, aligning himself with a camp of evangelists who’ve pioneered and advanced AI technologies while simultaneously warning of their potential to end mankind.

His departure came as a surprise to those both inside and outside of the company: Altman was still sending regular emails to employees as of late Friday morning, according to a person familiar with the matter.

As chief executive officer, Altman turned OpenAI into the most consequential AI company in the world. The company was recently in talks to sell employee shares to investors at a valuation of $86 billion. ChatGPT and OpenAI’s image generator Dall-E brought generative AI into the mainstream. Both tools leverage a technology that trains on vast swathes of digital data and can produce human-like content such as images, text and code when prompted.

Murati joined OpenAI in 2018 and was made CTO last year. “Given her long tenure and close engagement with all aspects of the company, including her experience in AI governance and policy, the board believes she is uniquely qualified for the role and anticipates a seamless transition while it conducts a formal search for a permanent CEO,” the company said in its statement.

Greg Brockman, a co-founder of OpenAI who had been chairman of the board, is also leave his board post but will still serve as president of OpenAI.

Microsoft Corp., which has pumped $10 billion into OpenAI, fell as much as 2.4% on the news of Altman’s departure. The company said in a statement that it has “a long-term relationship with OpenAI and remains committed to their team as we bring this next era of AI to our customers.”

Founded in 2015, OpenAI released ChatGPT about a year ago, setting off a rush of interest in AI technology. About 100 million people use ChatGPT each week, the company said in November, and more than 90% of Fortune 500 businesses are building tools on OpenAI’s platform. The company provides its software to businesses, and is on track to have annual revenue of about $1 billion, Bloomberg reported in August.

At the same time, OpenAI is facing growing competition from well-funded rival products developed at other startups and tech giants, including at Alphabet Inc.’s Google.

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