Sam Altman took to the witness stand to defend his reputation in the Musk v. Altman trial on Tuesday, as Elon Musk’s lawyers peppered the OpenAI CEO with hours of questions regarding his alleged history of deceptive behavior.

The cross examination was a much needed win for Musk, who has so far struggled to make a convincing case. Tuesday’s testimony included several heated exchanges in which the OpenAI CEO had to respond to allegations from former colleagues suggesting he’s untrustworthy.

Highlighting this evidence is not only important for Musk winning over a jury, but also for beating OpenAI in the court of public opinion. Days before the trial started, Musk texted OpenAI President Greg Brockman and told him that he and Altman would soon “be the most hated men in America.”

Musk’s lawsuit accuses Altman of effectively stealing the OpenAI charity, and taking the $38 million Musk donated to the non-profit organization and using it to create a for-profit business worth more than $850 billion.

However, there was little evidence on Tuesday to address the gaps in Musk’s legal case. Altman and Sam Teller, Musk’s former chief of staff, testified on Tuesday that they did not recall Musk ever attaching any special conditions to his donations to OpenAI. Additionally, it appears increasingly likely that Musk filed his case too late, years after he made his last donation to OpenAI and developed suspicion that the organization had breached its charitable trust. By then, the statute of limitations had already expired.

Brockman and his wife, Anna, sat in the gallery alongside OpenAI’s chief futurist, Joshua Achiam. While Altman and Brockman were present to watch Musk on the witness stand, Musk did not stay for Altman’s testimony. (Flight records suggest he was traveling to the Washington, DC area on Tuesday to fly to China with President Donald Trump.)

Before fielding questions from Musk’s lawyers, Altman had the chance to tell his side of the story, answering gentle questions from OpenAI’s lawyers. Wearing a purple tie, Altman painted himself as an entrepreneur and investor who’s always been fascinated by, and concerned about, the power of artificial intelligence.

Altman testified that Musk has long been obsessed with controlling OpenAI. He recalled “a particularly hair-raising moment” when Musk suggested that control of OpenAI should pass to his children if Musk were to die. “We didn’t feel comfortable with that,” Altman said. Altman also suggested that Musk’s attempt in 2018 to start an AI unit within Tesla—and offering him the chance to run it—felt like a “vague, lightweight threat” that Musk would effectively crush OpenAI with or without him.

Bombarding Altman

Steven Molo, Musk’s lawyer, wasted no time in his cross examination, asking Altman:“Are you completely trustworthy?” as his first question. Altman responded that he believes so, and then Molo immediately asked whether the jury should trust the testimony he just gave. Altman responded, “That’s up to them. I’m not going to tell the jury what to think.” Here’s the heated exchange that followed, as best as WIRED could capture it:

Molo: Do you always tell the truth?

Altman: I'm sure there is some time in my life where I have not.

Molo: Do you tell lies to advance your business interests?

Altman: No.

Molo: Have you misled people with whom you do business?

Altman: I do not think so.

Molo: Do they think so?

Altman: I can't answer that for other people.

Molo: You’ve repeatedly been called a liar by people you’ve done business with, right?

Altman: I've heard people say that.

Molo went through accusations against the OpenAI CEO from former OpenAI executives and board members—including Musk, former OpenAI chief scientist Ilya Sutskever, former chief technology officer Mira Murati, and former board member Tasha McCauley, as well as Anthropic cofounders Dario and Daniela Amodei—and interrogated Altman about them one by one. Molo even brought up accusations from nearly 15 years ago when Altman ran Loopt, a location-sharing startup, alleging he lied about the company’s daily active user count.

Altman tried his best to evade these questions, asking Molo to cite specific testimonies and claiming he was unaware of certain allegations.

Later, Molo was able to get clearer answers out of Altman regarding his investments in companies that have struck deals with OpenAI. On Monday night, news broke that a House oversight committee had sent a letter to Altman asking for more information regarding his potential financial conflicts that could interfere with his work at OpenAI.

Altman testified that he owns a nearly $2 billion equity stake in the nuclear energy startup, Helion. He also confirmed that OpenAI struck an agreement with Helion in 2024 that would allow OpenAI to purchase energy for AI development, should Helion develop its novel nuclear fusion technology successfully (currently, Helion doesn’t sell energy to anyone). Altman also said he has a $600 million stake in Stripe, and is an investor in Reddit and Cerebras, all of which have deals with OpenAI.

In response, Altman argued that he’s been a great steward of OpenAI. He testified that the nonprofit is one of the most well funded charities in history, claiming it has an equity stake in OpenAI worth more than $200 billion. “I do not believe I could have taken any other actions to get $200 billion into a nonprofit,” said Altman.

Power Struggle

While Altman tried to characterize Musk as the control-obsessed CEO in this trial, Molo suggested that Altman cares just as much about power. Altman admitted on the stand that he, at one point around 2017, was thinking about running for governor of California. (Late that year, he said on stage that he was no longer considering a run, according to Fortune.)

Molo also questioned whether OpenAI’s nonprofit board truly has the ability to appoint and fire executives at the company—which OpenAI has argued it does. Molo presented texts between Altman, Microsoft CEO Satya Nadella, and tech executive Bret Taylor from the weekend after Altman’s firing. The texts showed the three men discussing appointments for a new OpenAI board that would be pleasing to them all—including Taylor himself, who ultimately became the board chair.

Altman responded by saying he needed these reassurances in order to come back to run OpenAI, and that it was ultimately the board that fired him who appointed new members and rehired him.

“I almost didn’t come back because I was so upset. I thought there had been such a failure in governance, and the way the board had gone about this left such a lack of confidence from the people that needed to run the company,” said Altman. “Everything I had built was going to get destroyed. I was willing to run back into a burning building.”

Today, Altman sits on OpenAI’s board, which he testified was quite common for CEOs. Molo asked at one point whether Altman would ever fire himself. Altman, who may return to the stand on Wednesday, said this was not in his current plans.

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