OpenAI Board Says Sam Altman Will Not Return as C.E.O.

The board of directors of OpenAI, the high-flying artificial intelligence start-up, said in a note to employees on Sunday night that its former chief, Sam Altman, would not be returning to his job, while naming his second interim replacement in two days. Emmett Shear, the former chief executive of Twitch, will replace Mira Murati as interim chief executive of OpenAI, the board said. Ms. Murati, a longtime OpenAI executive, had been appointed to that role after Mr. Altman’s ouster on Friday. The board said Mr. Shear has a “unique mix...