OpenAI has named ex-Twitch boss Emmett Shear as interim CEO, while outgoing chief Sam Altman moved to backer Microsoft, in a surprise turn of events that capped a tumultuous weekend for the start-up at the heart of an artificial intelligence boom.
The appointments, settled late on Sunday, followed Altman's abrupt ousting just days earlier as CEO of the ChatGPT maker and ended speculation that he could return.
Microsoft rushed in to attract some of the biggest names that left OpenAI, including another co-founder Greg Brockman, to keep key talent out of the hands of rivals while seeking to stabilise OpenAI, in which it has invested billions.
The start-up's newly appointed interim head moved quickly to dismiss speculation that OpenAI's board ousted Altman due to a spat over the safety of powerful AI models.
Shear vowed to open an investigation into the firing, consider new governance for OpenAI and continue its path of making available technology such as its viral chatbot.
"I'm not crazy enough to take this job without board support for commercialising our awesome models," Shear said, adding: "OpenAI's stability and success are too important to allow turmoil to disrupt them like this."
The start-up dismissed Altman on Friday after a "breakdown of communications", according to an internal memo seen by Reuters.
Governing OpenAI is a non-profit. Its four-person board as of Friday consists of three independent directors holding no equity in OpenAI and chief scientist Ilya Sutskever.
"I deeply regret my participation in the board's actions. I never intended to harm OpenAI. I love everything we've built together and I will do everything I can to reunite the company," Sutskever said in a post on the X social media platform.
Sutskever, as well as former interim CEO Mira Murati, were among the nearly 500 employees who threatened to leave the company on Monday unless the board stepped down and reinstated Altman and Brockman, according to a letter seen by Reuters.
The staff also demanded the appointment of two new independent directors to the board.
"Your actions have made it obvious that you are incapable of overseeing OpenAI," the employees said in the letter.
"Microsoft has assured us there are positions for all OpenAI employees at this new subsidiary should we choose to join."
OpenAI did not immediately respond to a request for comment. It was not clear why Murati had stepped down as interim CEO.
A source familiar with the matter said OpenAI employees were split between different ideals.
Some were focused on building artificial general intelligence and against moving too fast without sufficient guardrails, while others recruited after the success of ChatGPT were more keen on quickly building and launching products akin to a traditional start-up, the source said.
Altman was becoming CEO of a new research group inside Microsoft and would be joined by other departing OpenAI colleagues who quit following his ouster, Microsoft CEO Satya Nadella said in posts on X.
Microsoft has invested billions of dollars in OpenAI and staked its future on the start-up, releasing what it called AI copilots to business customers based on OpenAI's technology.
Nadella and Shear both said their companies remained committed to their partnership, while resources would go to Altman's new group at Microsoft as well.
Australian Associated Press