OpenAI co-founder John Schulman has left the artificial intelligence startup he co-founded in 2015 for competitor AI firm Anthropic, leaving just three original co-founders still serving the firm. In addition to Schulman’s departure, OpenAI’s product manager Peter Deng also quietly left the company some time ago while president Greg Brockman is taking an extended leave of absence, according to an Aug. 5 report from The Information. In an Aug. 6 post to X, Schulman announced his departure from OpenAI after working there for nearly nine years, saying he’d made the “difficult decision” to move to…