Former OpenAI CEO Sam Altman returns to headquarters for talks following his abrupt ouster

Sam Altman, the recently ousted CEO of OpenAI, arrived as a guest Sunday at the headquarters of the company he founded.

Altman posted a photo of himself on X, formerly Twitter, wearing an OpenAI visitor badge, writing, “first and last time i ever wear one of these.”

Jason Kwon, OpenAI’s chief strategy officer, also posted a photo of Sam with the badge. Altman’s appearance at OpenAI HQ followed news that the company’s investors were pushing to reinstate him as CEO one day after he was ousted by the board, according to people familiar with the matter.

Over the past 24 hours, a large group of OpenAI employees, including executives, also have expressed support for Altman on social media by sharing hearts in response to one of his posts. Microsoft, Sequoia Capital, Tiger Global and venture firm Thrive Capital are part of an effort to reinstate Altman or have been in discussions with him, sources familiar told CNBC.

On Saturday morning, OpenAI COO Brad Lightcap wrote in a memo to employees, obtained by CNBC, that the board’s announcement took everyone by surprise.

“We have had multiple conversations with the board to try to better understand the reasons and process behind their decision,” Lightcap wrote. “These discussions, and options regarding our path forward, are ongoing this morning.”

Those discussions have now evolved into media reports that Altman may return to the company, along with OpenAI president Greg Brockman, who quit Friday after news of Altman’s departure.

— CNBC’s Rohan Goswami and Jordan Novet contributed reporting.