Microsoft CEO Satya Nadella passes through security at the federal courthouse during proceedings in the trial over Elon Musk's lawsuit against OpenAI in Oakland, California, on May 11, 2026. Karl Mondon | AFP | Getty Images Microsoft CEO Satya Nadella took the stand to testify in the Musk v. Altman trial in federal court in Oakland, California, on Monday.  Nadella, wearing a navy suit with a blue tie, began his testimony by answering questions about his role at Microsoft and the early days of the company's strategic partnership with OpenAI. In 2024, Elon Musk sued OpenAI , its CEO, Sam Altman , and its president, Greg Brockman , alleging that they went back on their vow to protect the artificial intelligence company's nonprofit structure and follow its charitable mission.…