About noon on Nov. 17, Sam Altman, CEO of OpenAI, logged into a video call from a luxury hotel in Las Vegas. He was in the city for its inaugural Formula One race, which had drawn 315,000 visitors including Rihanna and Kylie Minogue.

Altman, who had parlayed the success of OpenAI’s ChatGPT chatbot into personal stardom beyond the tech world, had a meeting lined up that day with Ilya Sutskever, chief scientist of the artificial intelligence startup. But when the call started, Altman saw that Sutskever was not alone — he was virtually flanked by OpenAI’s three independent board members.

Instantly, Altman knew something was wrong.