OpenAI’s board hired former Twitch chief Emmett Shear as chief executive officer, defying calls from investors to reinstate the ousted Sam Altman, according to people familiar with the matter.

Shear stepped down as CEO of Amazon.com Inc.’s game-streaming site Twitch earlier this year. He won over directors because he appeared to recognize the existential threats that AI presented, one of the people said. A computer scientist who spent more than a decade building Twitch into one of the world’s most successful video platforms, Shear is regarded as having the heft to lead a large engineering group, the person added.

Like some members of OpenAI’s board, Shear has ties to the AI-skeptical effective altruism movement, which sees risks posed by advanced AI. Many effective altruists — a pseudo-philosophical movement that seeks to donate money to head off existential risks — have imagined scenarios in which a powerful AI system could be used to create serious and widespread harm.

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Shear’s appointment marks the latest twist in a saga that erupted with Altman’s shock firing, which stunned Silicon Valley and left the startup at the center of the AI development frenzy in chaos. OpenAI and its globe-trotting co-founder Altman kicked off a race for artificial intelligence supremacy from Washington to Beijing, inviting comparisons to Bill Gates and Steve Jobs.

The decision to hire Shear is a stinging rebuke to investors led by Microsoft Corp. and Thrive Capital, who urged the board to step down and wanted Altman back at the helm.

Board members of the San Francisco-based startup reached out to at least two prominent executives in the technology industry in hopes one would take the role, one of the people said, asking not to be identified divulging private overtures.

Representatives for OpenAI and Shear didn’t respond to requests for comment.

OpenAI Chief Scientist Ilya Sutskever, who orchestrated Altman’s dismissal, told staff that Altman wouldn’t be returning.

Also Read: Open AI negotiations to reinstate Sam Altman snag over board role