Elon Musk’s explosive legal battle with OpenAI intensified in federal court Thursday, where a judge abruptly shut down his repeated warnings about artificial intelligence “extinction scenarios” during testimony that veered between technical disputes and apocalyptic claims. The moment underscored just how heated the trial has become as Musk and OpenAI’s leadership fight over the future, control and billions of dollars tied to one of the world’s most powerful AI companies.

Courtroom Tensions Surge as Musk Faces Aggressive Cross-Examination

The trial between Musk and OpenAI continued with sharp exchanges during cross-examination, as OpenAI’s legal team pressed the Tesla CEO on his role in the company’s founding and his current motivations. Witness testimony has already exposed private emails, text messages and diary entries that reveal the early formation of OpenAI and the breakdown of Musk’s relationship with Sam Altman.

The case is pulling in some of Silicon Valley’s most influential figures, with multiple high-profile witnesses expected to testify about the origins of the feud between Musk and Altman. Altman himself is scheduled to take the stand later in the three-week trial.

Musk’s Core Claim: A Broken Founding Promise

Musk, who co-founded OpenAI in 2015, argues that Altman, OpenAI and president Greg Brockman violated a foundational agreement by shifting the organization from a nonprofit mission into a for-profit structure.

He claims the change unjustly enriched executives and is seeking to reverse the conversion while also demanding $134 billion in damages be redirected to OpenAI’s nonprofit arm.

OpenAI strongly rejects the allegations and argues Musk was fully aware of plans to create a for-profit structure. The company’s attorneys say Musk is “motivated by jealousy” after leaving OpenAI in 2018 following a failed attempt to take control. OpenAI also maintains it remains overseen by its nonprofit structure.

Rapid-Fire Questioning Pushes Musk on the Defensive

OpenAI’s lead attorney William Savitt continued aggressive questioning Thursday, focusing on what Musk knew about OpenAI’s structure and its transition toward a for-profit model.

Musk repeatedly pushed back, insisting his original intent was central to the case. He responded with frustration, repeating a key argument he has used throughout the trial.

“you can’t just steal a charity”

Judge Yvonne Gonzalez Rogers intervened during the testimony, striking Musk’s repeated charity remark from the record.

“That portion is stricken, we’ve heard it many times.”

xAI Question Sparks Heated Exchange

Savitt also questioned Musk about xAI, the artificial intelligence company he founded in 2023, pressing him on why it was not established as a nonprofit.

Visibly irritated after being cut off during longer responses, Musk pushed back forcefully.

“I started OpenAI as a non-profit.”

He added that OpenAI only shifted to a for-profit model in recent years.

“That is the entire basis for this whole lawsuit,” Musk said. “Why would I start another non-profit when I already started a non-profit?”

Judge Shuts Down AI Extinction Claims

The most striking moment came when Musk discussed the risks of advanced AI systems, warning of extreme outcomes if development goes wrong.

“The worst-case situation is where it is a terminator situation,” Musk said, “where AI will kill us all.”

Judge Gonzalez Rogers quickly stepped in and signaled the line of questioning had gone too far.

After jurors left the courtroom, she addressed the legal teams directly.

“We are not going to talk much about extinction in this case. They got it, that’s enough.”

Musk’s Longtime Aide Testifies on Financial Support

Following Musk’s testimony, Jared Birchall, a key executive in Musk’s business network, took the stand. Birchall, who leads Musk’s family office and serves as CEO of Neuralink, said he began working with Musk in 2016.

He testified that he handled Musk’s financial contributions to OpenAI, but said Musk made all donation decisions.

Birchall said he processed roughly 60 donations totaling about $38 million between 2016 and 2020. Those contributions included payments tied to OpenAI operations, including rent for its Pioneer Building space in San Francisco.

High-Stakes Trial Draws Silicon Valley Attention

The trial, which began with jury selection in Oakland, California, has already delivered combative exchanges and dramatic testimony. Musk clashed repeatedly with Savitt earlier in the week, accusing the attorney of trying to mislead him.

After Wednesday’s session, the judge effectively dismissed concerns about Musk’s refusal to answer simple yes or no questions, noting that such friction is common in litigation.

Silicon Valley is closely watching the case, not only for its revelations about OpenAI’s origins but also for its potential impact on the AI industry’s financial future. OpenAI is reportedly preparing for a public offering that could value the company at around $1 trillion.

A ruling in Musk’s favor could significantly complicate that plan and potentially benefit his competing AI venture, xAI.

The nine member jury will ultimately decide liability, while Judge Gonzalez Rogers will determine any remedies, shaping the future of one of the most influential artificial intelligence companies in the world.