San Francisco, Nov 21 : After hiring Sam Altman to lead Microsoft's advanced AI research, the company's Chairman and CEO Satya Nadella has said that it's still possible that Altman could return to OpenAI in some capacity. In an interview with CNBC, Nadella said that Microsoft wants Altman and former OpenAI president Greg Brockman to have a fantastic home if they're not going to be in OpenAI. Asked whether Altman would return to OpenAI, Nadella said: 'That's for, you know, the OpenAI board and management and the employees to choose ' (Microsoft) chose to explicitly partner with OpenAI (and) obviously that depends on the people at OpenAI staying there or coming to Microsoft, so I'm open to both options.' It means that Altman's move to Microsoft is still not a done deal yet, as more than 500 employees at OpenAI on Monday reportedly threatened to resign and join Microsoft. OpenAI has nearly 770 employees. Altman and Brockman are still willing to return to OpenAI if the remaining board members who fired him step aside, multiple sources told The Verge. Nadella said that Microsoft would want to see 'something change around the governance' at OpenAI going forward, including around its investor relations. Microsoft, which has invested over $10 billion into OpenAI to date does not have a seat on OpenAI board. 'It's clear something has to change around the governance ' we'll have a good dialogue with their board on that, and walk through that as that evolves,' Nadella told CNBC. On Monday, in a letter to OpenAI's board, more than 500 current OpenAI staffers said that "Microsoft has assured us that there are positions for all OpenAI employees at this new subsidiary should we choose to join". OpenAI chief scientist Ilya Sutskever, who reportedly led efforts to remove Altman, said on X that he deeply regrets his 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," he noted. The letter read that the process through which the board terminated Sam Altman and removed Greg Brockman from the board has "undermined our mission and company". "Your conduct has made it clear you did not have the competence to oversee OpenAl. When we all unexpectedly learned of your decision, the leadership team of OpenAl acted swiftly to stabilise the company," said the letter. /IANS