Anthropic was founded by OpenAI exiles. It’s adding one more. On Tuesday, former OpenAI co-founder Andrej Karpathy announced on X that he will be joining Anthropic, seemingly to work on the lab’s research and development team. “Personal update: I’ve joined Anthropic. I think the next few years at the frontier of LLMs will be especially formative,” he wrote. “I am very excited to join the team here and get back to R&D. I remain deeply passionate about education and plan to resume my work on it in time.” Karpathy had an on-again, off-again relationship with OpenAI, serving as a founding member of the group and research scientist from 2015 to 2017, before Elon Musk poached him to serve as Tesla’s director of artificial intelligence. He rejoined OpenAI in 2023 and hung on for about a year before stepping away again in the wake of the very dramatic and short-lived ouster of Sam Altman as CEO—though Karpathy denied his exit had anything to do with that whole situation. It’s hard not to read Karpathy’s move to Anthropic in the context of the Cold War between the two major frontier labs. Not only is Anthropic made up largely of OpenAI send-offs, but it’s also started to act in an “enemy of my enemy is my friend” fashion. Earlier this month, Anthropic announced that it was going to start using computing power made available by SpaceX (née xAI) despite the fact that CEO Elon Musk has repeatedly referred to the company as “evil.” Turns out he must think it is less evil than a Sam Altman-led OpenAI, and given that his lawsuit to punish Altman failed, might as well lend support to his biggest rival.