OAKLAND, Calif. — Elon Musk fired back at OpenAI’s lawyer in a tense cross-examination during the second day of the long-awaited trial that pits one tech billionaire against another.

The Tesla and SpaceX owner filed a lawsuit against OpenAI CEO Sam Altman, accusing him of betraying the public by enriching himself through the AI company they founded together in 2015 as a nonprofit.

“They can’t have it both ways,” Musk said of OpenAI on Wednesday, during his second day on the stand. “They can’t have a nonprofit and free funding and the positive halo effect of being a nonprofit charity and also enrich themselves greatly.”

OpenAI completed a tumultuous corporate restructuring in October, shifting its capped-profit model to a more traditional for-profit structure. This for-profit arm, which continues to be overseen by a nonprofit foundation, raised $122 billion in its latest funding round that closed last month.

“I formed many tech companies. I could have done so with OpenAI. I chose not to, I chose to do something that would be a charity,” Musk said. “I deliberately chose to create this as a nonprofit for the public good.”

When his cross examination began, Musk pushed back against OpenAI’s lawyer Bill Savitt, who claimed that Musk was “never committed to OpenAI being a nonprofit.”

“Your questions are not simple. They’re designed to trick me, essentially,” Musk told the lawyer. He accused Savitt of being "misleading" with his questioning when he pointed out that Musk didn't donate $100 million to OpenAI despite claiming to have done so in his earlier deposition.

When asked about the $1 billion he originally promised to OpenAI, Musk began to tout the value of other things he contributed, such as his reputation. It prompted the judge to remind Musk to answer the question.

Musk confirmed that he never followed through on the $1 billion commitment — something that Altman's team pointed out in their counterclaim. Musk told Savitt that was because he “lost confidence in the team.” Instead, he said he contributed a total of $38 million.

The tech mogul, who left the board of OpenAI in 2018, seeks to stop the ChatGPT maker from becoming a for-profit company. He launched his own AI company, xAI, in 2023 as a for-profit company — “because that’s how I’ve created all my other companies,” he said on the witness stand.

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Savitt also questioned Musk’s motivations ahead of his testimony on Tuesday, accusing the tech mogul, who left the board of OpenAI in 2018, of abandoning the organization simply because he “didn’t get his way.” He added that Musk was dismissive of OpenAI employees focused on safety and had called them “jackasses.”

When asked on Wednesday about whether he ever used such language to employees, Musk responded in his testimony: “It’s possible I did it on occasion.” He said it would have been something like, “Don’t be a jackass.”

“Sometimes you have to use language that gets people out of their comfort zone,” Musk added. “If we’re going in the wrong direction … you have to use strong language to get them back on course.”

For Musk and Altman, the lawsuit is the culmination of a years-long feud that has sometimes led the two former associates to trade public barbs online. Altman was in the room Wednesday as Musk testified.

Musk is demanding an estimated $134 billion in damages from OpenAI and Microsoft, one of OpenAI’s top financial backers and a co-defendant in the case. He claims OpenAI benefited from his money, advice, recruiting efforts and connections.

But Altman’s side refutes the credit he takes, claiming that Musk never followed through on the $1 billion he’d originally promised to give OpenAI, and that he quit when Altman and fellow co-founders Greg Brockman and Ilya Sutskever refused to let Musk control the enterprise or absorb it into Tesla.

“I just needed to make sure it would go in the right direction,” Musk said in court on Wednesday. “We generally agreed, or I thought we agreed, that I would have initial control and very quickly I would lose majority control of the company.”

Musk described himself as “a fool who created free funding for them to create a startup” when he intended to create a nonprofit that nobody would own stock in.