Elon Musk, the CEO of SpaceX and Tesla, took the stand as the first witness in his billion dollar lawsuit against OpenAI in federal court in Oakland. The lawsuit accuses OpenAI CEO Sam Altman, co-founder and president Greg Brockman, and Microsoft of betraying the company's original nonprofit mission to benefit humanity. Musk is seeking sweeping remedies, including changes to OpenAI's corporate structure and removal of Altman and Brockman. His side estimates potential damages in the hundreds of billions. The other side argues that Musk is motivated by jealousy and regret for leaving OpenAI. The trial is set to run roughly four weeks and OpenAI is aiming for an IPO at a reported $852 billion.