Closing arguments conclude in Musk v. Altman, jury to deliberate next week

OpenAI CEO Sam Altman arrives at the federal courthouse, as the trial in Elon Musk's lawsuit over OpenAI's for-profit conversion continues, in Oakland, California, U.S., May 14, 2026.

Manuel Orbegozo | Reuters

The first phase of the Musk v. Altman trial concluded proceedings in federal court in Oakland, California, on Thursday after attorneys for Elon Musk and OpenAI presented their closing arguments to the jury.

The nine-person jury, which is made up of six women and three men, will begin deliberating on Monday. The jury’s verdict will be advisory, which means Judge Yvonne Gonzalez Rogers will make the final decision on liability.

“You must decide the case solely on the evidence before you,” Gonzalez Rogers told the jury Thursday morning, in reading out the formal instructions. “You will recall you took an oath to do so.”

Musk sued OpenAI, its CEO Sam Altman and Greg Brockman, the company's president, in 2024, alleging they went back on their commitment to keep the artificial intelligence startup a nonprofit and for unjustly enriching themselves. Musk, who co-founded OpenAI alongside Altman and Brockman in 2015, claims the roughly $38 million he donated to the company was used for unauthorized commercial purposes. 

During Thursday’s proceedings, Musk’s lawyer, Steven Molo, reiterated his arguments that OpenAI failed to open source its technology, prioritize AI safety and follow nonprofit customs and practices. He also claimed that OpenAI insiders and investors, including Altman, Brockman and Microsoft, enriched themselves at Musk’s expense. 

Sarah Eddy and William Savitt, attorneys for OpenAI, pushed back on Molo’s statements on Thursday. They said Altman and Brockman never made commitments to Musk about OpenAI’s corporate structure, and that Musk’s donations were spent and used properly. They also noted that the Tesla and SpaceX CEO filed the lawsuit only after launching his competing AI startup, xAI.  

“He never cared about the nonprofit structure,” Eddy told the jury. “What he cared about was winning.” 

Microsoft is also named as a defendant in the lawsuit, and attorney Russell Cohen presented the company’s closing arguments to the jury. Musk accused Microsoft, OpenAI's principal investor, of aiding and abetting the company's purported breach of charitable trust. Cohen said Microsoft had no knowledge of those events and couldn't have participated in them. 

William Savitt, lead attorney representing OpenAI and Sam Altman, speaks to the press outside the Ronald V. Dellums US Courthouse where the Elon Musk v OpenAI trial proceeded for its third day in Oakland, California, on April 29, 2026.

Amy Osborne | AFP | Getty Images

As the jury starts deliberations on Monday, the second stage of the trial, known as the remedies phase, will also begin. 

Gonzalez Rogers will hear arguments about the potential damages and next steps that should be taken if OpenAI, Altman and Brockman are found liable. The jury will not weigh in on this phase.

Musk has asked for a range of outcomes in the lawsuit since it was first filed in 2024. Most recently, he asked the judge to consider removing Altman and Brockman from their roles at OpenAI, and to unwind the company’s 2025 recapitalization. 

In January, Musk’s lawyers said their client was entitled to up to $134 billion in damages from OpenAI and Microsoft, calling them “wrongful gains.” His team now says any “ill-gotten gains” should be returned to OpenAI’s foundation.

There will only be a decision in the remedies phase if there’s a finding of liability. 

Gonzalez Rogers has presided over prior high-profile technology cases, which could explain why she chose to enlist the help of an advisory jury.

"Judges normally empanel advisory juries when they either want the community judgment of the jurors or they want 'cover' in a highly visible case," Steven Baicker-McKee, an associate law professor at Duquesne University, told CNBC. 

Former President Barack Obama appointed Gonzalez Rogers to U.S. District Court for the Northern District of California in 2011, and she previously oversaw the antitrust case between Epic Games and Apple.

Gonzalez Rogers showed little patience for any shenanigans from the lawyers during the first phase of the Musk v. Altman trial, repeatedly chiding representatives for both parties when they stepped out of line. 

“You do not want to be held in contempt I guarantee you,” she warned one lawyer on Tuesday.

With the jurors, however, Gonzalez Rogers has been warm and friendly, cracking jokes and even bringing them chocolates on one occasion. She concluded Thursday’s proceedings by reminding the jury that lunch will be provided during deliberations.

—CNBC's Kate Rooney contributed to this report.

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