Judge in Musk v. Altman seats nine-person jury. Opening arguments start Tuesday

The nine-person jury was seated on Monday in the high-stakes legal battle between longtime friends turned rivals Elon Musk and Sam Altman at a federal courthouse in Oakland, California.

Judge Yvonne Gonzalez Rogers is overseeing the proceedings between the world's richest person and the CEO of OpenAI. Opening arguments are scheduled to begin on Tuesday, and CNBC will be in the courtroom.

Musk, who co-founded OpenAI in 2015, sued the company, Altman and Greg Brockman, OpenAI's president, in 2024, alleging they reneged on their commitments to keep the artificial intelligence lab a nonprofit and follow its charitable mission. OpenAI has repeatedly dismissed Musk's lawsuit as "baseless." Musk left OpenAI's board in 2018, and five years later started xAI as a rival, merging that company with SpaceX earlier this year.

Musk has sought a number of different remedies over the course of the case, including the removal of Altman and Brockman from their roles at OpenAI. Musk's lawyers said in January that he should receive up to $134 billion in "wrongful gains," though he has since asked to funnel those funds back into the OpenAI charity. 

Gonzalez Rogers opted to divide the trial into two parts: a liability phase to decide if any wrongdoing occurred, and a remedies phase to determine the appropriate damages and next steps. The jury will weigh in during the liability phase only, and its verdict will be advisory, which means Gonzalez Rogers will make the final decision in both sections of the trial. 

The liability phase of the trial is expected to wrap up by May 21, Gonzalez Rogers said Monday.

Gonzalez Rogers started the proceedings by welcoming the prospective jurors to the courtroom. She cracked some jokes as she explained the case laid out the trial's schedule.

Lawyers grilled prospective jurors on their views on AI, Musk and Altman. Some confessed to holding negative views of Musk due to his political ideology.

"The reality is people don't like him," Gonzales Rogers said at one point. She expressed confidence that the jurors selected will respect the judicial process and the facts of the case.

Altman and Brockman were in the courtroom on Monday.

Musk alleges in his lawsuit that he was "assiduously manipulated" and "deceived" by OpenAI, Altman and Brockman and their promises to "chart a safer, more open course than profit-driven tech giants." He has asked the judge to consider unwinding the company's recent restructuring, which cemented its structure as a nonprofit with a controlling stake in its for-profit business.

Musk and Altman have been in a public war of words for months leading up to the trial. That continued on Monday, with Musk writing in a post on X, "Scam Altman and Greg Stockman stole a charity. Full stop."

The comment followed a post from the OpenAI Newsroom account.

"We can't wait to make our case in court where both the truth and the law are on our side," OpenAI wrote. "This lawsuit has always been a baseless and jealous bid to derail a competitor."

Of the 26 claims that Musk asserted in 2024, only two remain: unjust enrichment and breach of charitable trust. Musk's lawyers dismissed two of the claims, fraud and constructive fraud, ahead of the trial in an effort to "streamline the case," according to a filing

The trial lands as Musk prepares to take SpaceX public in what's likely to be a record IPO and as OpenAI gears up for its own public offering expected later this year. The two companies combined are valued at over $2 trillion on the private market.

— CNBC's Lora Kolodny contributed to this report.

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