Image source, ReutersImage caption,
Investors are reportedly calling for Mr Altman to be reinstated
By Zoe Kleinman, technology editor, and Daniel Thomas, business reporter
The ex-boss of leading artificial intelligence firm OpenAI has posted a photo of himself at its HQ, but he's reportedly unlikely to return to the helm of the start-up.
Writing on X, formerly Twitter, Sam Altman is pictured holding a guest ID pass, commenting: "First and last time i ever wear one of these".
The 38-year-old helped launch the firm which created the popular ChatGPT bot.
On Friday the board dismissed Mr Altman saying it had lost confidence in him.
There were reports this weekend suggesting employees and investors including Microsoft were pushing for Mr Altman to be reinstated.
But, according to The Information tech news site, board director Ilya Sutskever told employees on Sunday night that Mr Altman would not return, prompting many to internally announce they were quitting.
Emmett Shear is expected to be named as the new interim chief executive, according to the the New York Times, citing an internal memo.
Mr Shear is an internet entrepreneur who was previously chief executive at Twitch.
Mr Altman and Greg Brockman - another co-founder who quit on Friday as the company's president - were invited to the firm's San Francisco headquarters for talks on Sunday.
The BBC has contacted OpenAI for comment.
Reports of Mr Shear's appointment have emerged despite OpenAI saying on Friday that its chief technology officer, Mira Murati, had been appointed as interim chief executive.
Mr Altman is seen as one of the most influential figures in the fast-growing generative AI space and his sacking sent shockwaves across the industry.
In a letter on Friday, the company's board accused him of not being "consistently candid in his communications with the board, hindering its ability to exercise its responsibilities".
The board did not specify what he is alleged to have not been candid about.
However, whatever the board was so alarmed about on Friday has perhaps been overtaken by the global reaction to its decision. There may also have been fears of Mr Altman setting up a rival company and taking OpenAI's top talent with him.
OpenAI's board of directors consists of Mr Sutskever and three independent directors - Quora chief executive Adam D'Angelo, technology entrepreneur Tasha McCauley, and Helen Turner from the Georgetown Center for Security and Emerging Technology.
Reports this weekend suggested his sacking had angered current and former employees who were worried it might affect an upcoming $86bn (£69bn) share sale.
The firm's venture capitalist backers and the tech giant Microsoft - which has a $10bn stake in OpenAI - have also believed to have called for his return.
Sources say there have been a couple of sleepless nights in Seattle, the headquarters of Microsoft, which has also integrated OpenAI's technology into its applications.
Image source, PA MediaImage caption,
OpenAI's bot ChatGPT is used by millions around the world
OpenAI is widely seen to be a company at its peak, with lucrative investment pouring in, and ChatGPT - which was launched almost a year ago - is used by millions.
Mr Altman has been the face of the firm's rise. More than that, he is seen by many as the face of the industry more widely.
He testified before a US Congressional hearing to discuss the opportunities and risks created by the new technology and also appeared at the world's first AI Safety Summit in the UK at the beginning of November.
His ousting sparked an outpouring of support from Silicon Valley bosses, including former Google chief executive Eric Schmidt who called Mr Altman "a hero of mine" and said that he had "changed our collective world forever".
Additional reporting by BBC business reporter Annabelle Liang