OpenAI on Wednesday said it reached an agreement for Sam Altman to return as CEO days after his shock ouster, capping a marathon discussion about the future of the startup at the centre of the artificial intelligence boom.

In addition to Altman’s return, the company agreed in principle to partly reconstitute the board of directors that had dismissed him. Former Salesforce co-CEO Bret Taylor and former US Treasury Secretary Larry Summers will join Quora CEO and current director Adam D’Angelo, OpenAI said.

Sam Altman said in a post on X: “I’m looking forward to returning to OpenAI.”

OpenAI on Monday had named ex-Twitch boss Emmett Shear as its interim CEO, while outgoing chief Altman had said he would move to Microsoft.

Altman had been sacked by OpenAI on Friday, the news coming as a surprise to both Altman and co-founder Greg Brockman, who quit the company following Altman’s ousting.

However, Brockman announced on Wednesday in a post on X that he would also be returning to the company following Altman’s reinstatement.

Microsoft CEO Satya Nadella —who had announced the hiring of Atman on Monday — welcomed this new development, calling it a “first essential step on a path to more stable, well-informed, and effective governance,” in a post on X.

The departures of Altman and Brockman on Friday blindsided many employees who discovered the abrupt management change from an internal message and the company’s public-facing blog.

In a letter first published by Wired, more than 738 of the 770 OpenAI employees threatened to leave the company if the board was not replaced.

Altman shot to fame with the launch of OpenAI’s artificial intelligence (AI) chatbot last year, which ignited a race to advance AI research and development, as well as billions being invested in the sector.