It’s been a hectic weekend for OpenAI, the artificial intelligence company behind ChatGPT.

The company’s board on Monday named a new interim CEO, three days after ousting co-founder Sam Altman from the position. And despite reports that executives and investors have been working to bring Altman back, the former CEO announced Monday that he will join Microsoft to help lead a new AI research team.

Greg Brockman, another OpenAI co-founder and former president who quit in solidarity with Altman, is also joining Microsoft, according to a post on X, formerly Twitter, from Microsoft CEO Satya Nadella. Hundreds of other employees are now threatening to quit to join Microsoft as well.

For those who have yet to catch up on the shakeup at OpenAI, here’s what we know so far: 

Why was Altman ousted?

OpenAI’s board of directors on Friday announced that Altman would depart as CEO and leave the board. 

A blog post said the board found Altman “was not consistently candid in his communications,” which was “hindering (the board’s) ability to exercise its responsibilities.” Reporting from the Washington Post and CNN found that tensions arose from Altman's push to commercialize the company's product, while the board wanted to move forward with the technology more cautiously.

The board also said Friday that Brockman would be stepping down as chairman of the board but keep his role at the company. Brockman quit his job at OpenAI soon after the announcement.

Wedbush Securities tech analyst Dan Ives wrote that the "train wreck situation at OpenAI" created by its four-person board may go down in tech history as one of the biggest debacle decisions in the history of Silicon Valley," according to a Sunday note.

Who are the board members of OpenAI?

Now that Altman and Brockman are out, the OpenAI Nonprofit board consists of chief scientist Ilya Sutskever and non-employees Adam D’Angelo, CEO of Quora; technology entrepreneur Tasha McCauley; and Georgetown Center for Security and Emerging Technology’s Helen Toner.

How did OpenAI staff react?

Hundreds of OpenAI employees have threatened to resign over the board’s actions, leaving the future of the AI company on shaky ground.

Axios and Wired reported that more than 500 of OpenAI's 700-plus employees have signed a letter urging the company’s board to resign. The employees threatened to join the newly-announced Microsoft subsidiary run by Altman and Brockman, noting that Microsoft “has assured us that there are positions for all OpenAI employees at this new subsidiary should we choose to join.” Microsoft is OpenAI’s biggest stakeholder with a roughly $13 billion investment.

“We are unable to work for or with people that lack competence, judgement and care for our mission and employees,” the letter reads.

The employees threatened to quit “imminently” unless all current board members resign, two new lead independent directors are appointed, and Altman and Brockman are reinstated. 

OpenAI chief scientist Ilya Sutskever, who is part of the board that ousted Altman, is one of the 505 employees to sign the letter. Sutskever on Monday said he regrets his participation in the board’s actions and “never intended to harm OpenAI,” according to a post on X. 

“I love everything we've built together and I will do everything I can to reunite the company,” he wrote.

Will Sam Altman return?

The Wall Street Journal and New York Times reported that OpenAI’s board was having second thoughts about the firing after receiving pushback from investors. Altman on Sunday posted a photo of himself to X wearing an OpenAI visitors’ badge at the company's San Francisco headquarters.  

The New York Times reported that OpenAI’s board told employees Sunday night that Altman would not be returning to his job. But the Verge on Monday reported that Altman and Brockman are still willing to return if the remaining board members step aside.

Who is Emmett Shear, the interim CEO of OpenAI?

OpenAI’s board of directors on initially named Mira Murati, the company’s chief technology officer, as interim CEO. The board reversed course on Monday, naming Twitch co-founder Emmett Shear as interim CEO.

Shear has noted his concerns about AI and is in favor of a slowdown in advancing AI technology.

"We can't learn how to build a safe AI without experimenting, and we can't experiment without progress, but we probably shouldn't be barreling ahead at max speed either," he said in a September post on X.

Shear said Altman’s removal had been “handled very badly," which "seriously damaged our trust.” He plans to hire an independent investigator to generate a report on Altman's firing.

“I will drive changes in the organization − up to and including pushing strongly for significant governance changes if necessary,” he said. “I will be rolling these out as they become clear over the 30-day period. OpenAI’s stability and success are too important to allow turmoil to disrupt them like this.”

Shear also denied that the board removed Altman over disagreements on safety.

"I'm not crazy enough to take this job without board support for commercializing our awesome models," he said.