A long-awaited trial between Elon Musk and Sam Altman’s OpenAI began in a federal court in Oakland, California on Monday morning.
Exactly https://t.co/hd6rx0aF2i
— Elon Musk (@elonmusk) April 27, 2026
In 2024, Musk, a major early investor and co-founder of OpenAI, sued OpenAI, its CEO Sam Altman, President Greg Brockman, and major backer Microsoft, claiming that they had defrauded him of billions of dollars by turning OpenAI from a non-profit to a for-profit.
Now, Judge Yvonne Gonzalez Rogers has seated a nine-person jury on Monday afternoon and opening statements will begin tomorrow. The trial will be divided into two parts. The first part is the liability phase, meant to last until May 21, when it will be passed on to the jury for an advisory verdict. Then, the judge will begin the remedies phase. Several very influential figures in the AI industry are expected to be called in for a testimony, including Musk, Altman, Brockman, and Microsoft CEO Satya Nadella. Both Altman and Brockman were in court for the first day of the trial, according to CNBC.
In the meantime, here’s everything you need to know.
When OpenAI was founded as a nonprofit AI lab in 2015, Elon Musk was one of its co-founders and a major early investor.
Then, Musk left the company in 2018. Prior to his departure, according to emails submitted to the court, Musk shared his opinion that “OpenAI is on a path of certain failure relative to Google” and that his company Tesla was “the only path that could even hope to hold a candle to Google.”
In 2023, he launched competitor xAI, an AI firm that he has since merged with another one of his companies, SpaceX. The joint xAI-SpaceX will make its market debut later this year, only months before a reported OpenAI IPO. Through xAI, Musk also made an unsolicited bid to acquire OpenAI for $97.4 billion in February 2025.
Shortly after Musk left, under Altman’s leadership, OpenAI changed its corporate structure, first to a “capped” for-profit company in 2019 and then finally into a for-profit public benefit corporation in late 2025. It also launched ChatGPT in 2022, to incredible success that catapulted the company to the top of the AI leaderboard.
Musk brought charges against the defendants in August 2024, claiming more than $130 billion in damages for executing a “deceit…of Shakespearean proportions,” according to the complaint, by allegedly manipulating Musk into thinking he was giving money to a non-profit when the plan all along was to turn OpenAI into a for-profit company.
“Do you want to set legal precedent in the United States that it is ok to loot a charity?” Musk claimed in a post on X on Monday. “I could have started OpenAI as a for-profit corporation. Instead, I started it, funded it, recruited critical talent and taught them everything I know about how to make a startup successful FOR THE PUBLIC GOOD. Then they stole the charity.”
In an amendment submitted earlier this month, Musk said that he would like those damages to be paid to OpenAI’s non-profit arm rather than to himself. On top of the damages, he wants the court to unwind OpenAI’s conversion to a for-profit and to have both CEO Sam Altman and President Greg Brockman ousted.
Just last week, Musk’s team dropped the fraud claims and decided to proceed solely on the claims of breach of charitable trust and unjust enrichment.
OpenAI denies the claims of fraud, arguing that Musk was involved in discussions to turn OpenAI into a for-profit company as early as late 2017. Musk allegedly wanted the company to merge with Tesla or for himself to be given majority control of any for-profit structure. OpenAI said they would not agree to Musk’s terms for the for-profit structure, which allegedly led to Musk leaving the company under the false assumption that OpenAI had no chance of success.
“Motivated by jealousy, regret for walking away from OpenAI and a desire to derail a competing AI company, Elon has spent years harassing OpenAI through baseless lawsuits and public attacks,” OpenAI said in a statement.
The company has also accused both Musk and Meta of “improper and anti-competitive behavior” before, and in the statement on Monday, claimed that Musk coordinated with Meta CEO Mark Zuckerberg to “undermine OpenAI’s mission.”
The trial could unearth new details about both Elon Musk and Sam Altman amid heightened scrutiny of both figures and their respective companies.
Over the past year, Musk and his companies were at the center of controversy after controversy. The billionaire’s actions as part of the Trump administration caused riots aimed at Tesla dealerships. His unceremonious dumping from Trump’s close circle, followed by reports of his frequent ketamine abuse, only amplified his bad reputation. In March, Musk was found to have misled investors in his acquisition of Twitter, but his team claimed that he did not face a fair trial because “so many jurors had antipathy toward Mr. Musk” that “the Court was unable to simply excuse those who expressed negative feelings towards him.”
Now his company, the joint xAI-SpaceX, is headed for a highly consequential IPO later this year, as the company continues to battle increased public and regulatory scrutiny due to Grok’s rampant creation of non-consensual nude images of women and children on X.
OpenAI is reportedly eyeing an IPO later this year as well, even though both the company and Altman haven’t had a great year either. ChatGPT has been accused of facilitating fatal mental health episodes, including a murder-suicide in Connecticut and the suicide of a 16-year-old boy. The company has also received a lot of public outrage for inking a deal with the Pentagon right after Anthropic allegedly passed on it for concerns over mass domestic surveillance and fully autonomous weapons.
A New Yorker investigation—recently boosted by Elon Musk on X, adding to its visibility—also refocused public scrutiny on Altman, with multiple sources claiming that Altman was untrustworthy and even a sociopath. Shortly after its publication, Altman’s home in San Francisco was hit with a molotov cocktail.
Source: Gizmodo