There used to be a team at Google called Google Brain and they all left to go to OpenAI after the employee protests against taking military AI contracts in 2018. Now Microsoft has those contracts and funneled $10B to OpenAI from the CIA. OK that's a little bit of exaggeration but not so much; I guess not all employees left, and Google Brain still technically exists. Also some of the brain employees went to other startups not only OpenAI.