• OpenAI CEO Sam Altman was fired last week, with the board of the company saying it "no longer has confidence in his ability to continue leading" the technology firm.
• Emmett Shear, the former co-founder and CEO of livestreaming site Twitch, was named as interim CEO early Monday.
• CNBC runs through what you need to know about Altman's successor.

It's been just a few days since Sam Altman, the former CEO of OpenAI, was ousted in a shock move and temporarily replaced by Chief Technology Officer Mira Murati, who served as the firm's interim chief executive. Now, a new replacement for interim CEO of OpenAI has been named.

After a weekend of rumor and speculation, Emmett Shear — former co-founder and CEO of Twitch — confirmed he will take the top job at probably the most high-profile AI company in the world. In a post on X, formerly Twitter, early Monday, Shear said he got a call from OpenAI asking him to become interim CEO of the company.

"After consulting with my family and reflecting on it for just a few hours, I accepted," Shear said in the X post. It comes after Altman, who led OpenAI through its development of the wildly popular generative artificial intelligence chatbot ChatGPT, was fired by the OpenAI board.

The reasons behind his departure are unclear, but some insiders had expressed concern that Altman wasn't the right fit for the company. He is involved in another company, the eyeball-scanning tech company Worldcoin, for example, and there were concerns that this may have served as a distraction.

Who is Emmett Shear?

Shear is a big name in Silicon Valley — but to most people, he is unknown.

Shear took Twitch — the livestreaming site he co-founded with Justin Kan, Michael Seibel, and Kyle Vogt in 2007 — from originally broadcasting the life of Kan 24/7, to a worldwide phenomenon.

Twitch was acquired by Amazon for $1 billion in 2014 and Shear stepped down as CEO of Twitch earlier this year.

During his time at the company, he faced tensions from streamers who believed that the platform wasn't defending their interests. It found itself locked in a tense battle with rival YouTube for talent, with the latter attracting several high-profile personalities from Twitch with lucrative exclusive broadcasting deals.

After Shear's departure from the streaming site, he became a partner at Y Combinator, the startup accelerator. Altman was formerly president of Y Combinator.

Before Shear started Twitch, he was the co-founder of Kiko Calendar, a calendar app he worked on through the 2005 Y Combinator program.

In his post Monday on X, Shear explained why he had taken the OpenAI job.

"I had recently resigned from my role as CEO of Twitch due to the birth of my now 9 month old son," Shear said in the post early Monday.

"Spending time with him has been every bit as rewarding as I thought it would be, and I was happily avoiding full time employment."

"I took this job because I believe that OpenAI is one of the most important companies currently in existence. When the board shared the situation and asked me to take the role, I did not make the decision lightly. Ultimately I felt that I had a duty to help if I could," he added.

Why it matters

The swift elevation of Shear to OpenAI's CEO puts him in charge of one of the most important companies in the AI world today.

OpenAI is known for its popular generative AI chatbot, ChatGPT.

The powerful technology behind that chatbot is called a large language model, or LLM. This is an AI model capable of processing and generating human language, based on training from vast amounts of data.

As head of OpenAI, Shear will likely face pressure from regulators who have been heavily scrutinizing AI model companies given the risks the technology poses around misinformation and potential displacement of jobs.

Earlier this month, the U.K. held a pivotal summit on AI safety, attended by major foundational AI companies, to discuss some of the most pressing issues in the field.

Particularly high on the list of discussion areas for world leaders was the "existential risk" that AI poses to humans.

Read more CNBC reporting on OpenAI

• Ousted OpenAI head Sam Altman to lead Microsoft's new AI team
• 'Damage control': Tech industry reacts to a chaotic weekend for OpenAI and Microsoft
• Hundreds of OpenAI employees threaten to follow Altman to Microsoft unless board resigns, reports say

Altman has himself warned of the threat of AI to eradicate humanity, despite being at the helm of a company that was working on rapidly advancing the technology.

Notably, like Altman and other tech leaders including Elon Musk, Shear has himself made several comments about the potential for AI to eradicate humanity.

On "The Logan Bartlett Show," a podcast hosted by Logan Bartlett, general partner at Redpoint Ventures, Shear said he think there's a "5-to-50" chance that AI may wipe out all human life today.

Further to this, Shear also said that the potential of AI going rogue in the future "should cause you to s--- your pants."

He added that a potentially sentient artificial intelligence known as artificial general intelligence or AGI could result not only in the eradication of humanity, but also "potential destruction of all value in the life chain," and a "universe-destroying bomb."

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Correction: Shear stepped down as CEO of Twitch earlier this year. An earlier version misstated the timing.

Clarification: The headline of this story has been amended to clarify that Shear has been named interim CEO of OpenAI.