Closing arguments begin in Musk v. Altman OpenAI trial

For Musk, the theory of the case rests on breach of charitable trust and unjust enrichment. He invested about $38 million in OpenAI in its early years, then accused Altman, Brockman and the company of abandoning the nonprofit promise that drew him in. OpenAI has countered that Musk’s claims are baseless and that outside capital was essential to compete at the top of the AI industry, where development demands extraordinary sums. The company has since taken in tens of billions of dollars from investors including Microsoft.

The closing phase exposed the personalities at the center of the dispute as much as the legal claims. Steven Molo, Musk’s lawyer, stumbled over his words and at one point referred to Greg Brockman as Greg Altman. He also incorrectly argued that Musk was not seeking money, while spending much of the day attacking Altman’s credibility and casting OpenAI’s leadership as untrustworthy. Those lapses mattered because the trial was no longer just about paperwork and restructuring. It was about whether jurors found Musk’s version of the company’s founding persuasive enough to support the claim that OpenAI changed course behind his back.

Altman had already testified earlier in the week, and the courtroom record showed a broader contest over motive. Musk himself was pressed on the role of xAI, his own competing artificial intelligence company, which gave OpenAI room to argue that the billionaire feud was not only about principle but also about control of the market and the narrative. The case has been described as a clash over whether OpenAI shifted into a moneymaking mode without Musk’s knowledge.