Billionaires feud in OpenAI trial as Sam Altman testifies in Oakland

The OpenAI fight in Oakland has become a referendum on who gets to govern advanced AI, with the courtroom serving as a stage for a billionaire feud that now reaches into boardrooms, charities and the structure of the company itself. Sam Altman testified in federal court before U.S. District Judge Yvonne Gonzalez Rogers in a proceeding that began with jury selection on April 27 and was already in its third week when he appeared.

The case traces back to OpenAI's founding in December 2015 as a nonprofit backed by an initial $1 billion commitment from Elon Musk, Altman and other tech figures. Musk left in 2018 after a power struggle and filed suit in 2024, arguing that OpenAI had drifted from its original mission. The dispute sharpened after OpenAI completed a major restructuring in October 2025 into a public benefit corporation controlled by a nonprofit, a move that valued the company at about $500 billion and left Microsoft with about a 27% stake.

Testimony has added new texture to the corporate split. Musk testified first and said Altman and Greg Brockman were trying to "steal a charity," while also pursuing settlement talks shortly before trial. Brockman said Musk had supported a for-profit transformation. Satya Nadella, the Microsoft chief executive, said Musk never contacted him to complain about Microsoft's investment in OpenAI. Altman later told the court he felt Musk had "abandoned" OpenAI and left the company in a difficult position.

The wealth on display in the Oakland courtroom matched the scale of the stakes. The three-week trial has featured an inflatable Elon Musk doll and fancy butt cushions, small signals of the fortunes behind a case that could shape how frontier AI companies are financed and controlled. A court filing has also said Altman holds more than $2 billion in stakes in companies that have done business with OpenAI, a detail that deepens the conflict-of-interest questions around a company whose mission, ownership and commercial reach are now being tested in public.