More than 500 employees at artificial intelligence company OpenAI have said that they will quit unless the board resigns and ousted CEO Sam Altman is reinstated.

The 505 staffers (Update: Now 721 employees) said that they would jump over to Microsoft, which has hired Altman, cofounder Greg Brockman, and others for a new AI research division.

Microsoft Azure
– Sebastian Moss

Altman was suddenly fired on Friday with the board claiming “he was not consistently candid in his communications with the board, hindering its ability to exercise its responsibilities.”

Mira Murati, OpenAI’s chief technology officer, was appointed as interim CEO, but replaced on Monday after she tried to negotiate Altman's return with the help of Microsoft CEO Satya Nadella.

Among the more surprising signees of the letter is Ilya Sutskever, the company’s chief scientist and a member of its board, who has been accused of being behind the entire coup.

"I deeply regret my participation in the board's actions," Sutskever said on Twitter/X. "I never intended to harm OpenAI. I love everything we've built together and I will do everything I can to reunite the company."

The board consists of OpenAI chief scientist Ilya Sutskever, independent directors Quora CEO Adam D’Angelo, technology entrepreneur Tasha McCauley, and Helen Toner, the director of strategy at Georgetown Center for Security and Emerging Technology.

In the letter, the OpenAI employees state that “the process through which you terminated Sam Altman and removed Greg Brockman from the board has jeopardized all of this work and undermined our mission and company.

“Your conduct has made it clear you did not have the competence to oversee OpenAI.”

They add: “Microsoft has assured us that there are positions for all OpenAI employees at this new subsidiary should we choose to join."

The company has 770 employees, so the departure would leave OpenAI struggling to continue development of its large language models and other AI projects.

Shares in Microsoft are up 1.4 percent this morning, with the company's valuation hitting record highs.

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