• Greg Brockman, OpenAI co-founder and president, is scheduled to testify Monday in Elon Musk’s lawsuit against OpenAI in California
• Musk is asking the court to force OpenAI back to its original non-profit structure, arguing the company abandoned its founding mission
• Musk claims OpenAI shifted from a public-interest AI lab into a commercial giant focused on profit and market dominance

One of OpenAI’s earliest architects is set to take the witness stand on Monday, May 4, as the courtroom fight between Elon Musk and the company behind ChatGPT enters another pivotal week.

Greg Brockman, OpenAI’s co-founder and president, is expected to testify in the California case brought by Musk, who is seeking to force OpenAI back to its original non-profit structure.

The testimony follows three days of closely watched courtroom appearances from Musk, who painted himself as an early backer sidelined after helping launch the artificial intelligence company.

The lawsuit, unfolding in Oakland before Judge Yvonne Gonzalez Rogers, has become one of the most consequential legal battles in the AI industry.

At the center of the dispute is Musk’s claim that OpenAI abandoned its founding mission of building artificial intelligence for the benefit of humanity and instead evolved into a commercially driven enterprise.

Musk, who co-founded OpenAI alongside Sam Altman and Brockman in 2015, argues that the company’s transition into a profit-oriented powerhouse violated the principles on which it was established.

He said OpenAI was conceived as a public-interest lab designed to ensure powerful AI systems would be developed safely and openly, not controlled by commercial interests.

During more than seven hours of testimony last week, Musk told the court he contributed $38 million to OpenAI between 2016 and 2020 and played a central role in shaping the organisation’s early direction.

He argued that his support was motivated by a desire to challenge Google’s dominance in AI and to prevent transformative technology from being shaped solely by profit incentives.

OpenAI has rejected Musk’s claims, arguing that its current structure remains anchored by a non-profit parent and that commercial expansion was necessary to raise the enormous capital required to build frontier AI systems.

The company has also challenged Musk’s motives, suggesting his legal campaign is driven less by principle than by rivalry and competition, particularly given the rapid rise of his own AI venture, xAI.

The argument has gained extra weight after Musk folded xAI, the company behind chatbot Grok, into SpaceX, further intensifying questions around his own commercial ambitions in the AI race.

The stakes in the trial are enormous. A ruling in Musk’s favour could complicate OpenAI’s plans for a public offering and reshape how major AI companies are structured, funded and governed.

It could also send shockwaves across a fiercely competitive sector where Google, Anthropic and fast-rising Chinese firms are racing to dominate the next era of artificial intelligence.

OpenAI chief executive Sam Altman, Musk’s former ally turned chief rival, is expected to testify later this month. Microsoft CEO Satya Nadella, whose company’s partnership with OpenAI has become a major focus of the case, may also be called to the stand.

Their testimony could prove decisive in a case that may shape not only OpenAI’s future, but the balance of power across the global AI industry.

Elon Musk skips Paris prosecutors’ summons over X, Grok investigation

Meanwhile, TheRadar earlier reported that billionaire Elon Musk failed to appear on Monday, April 20, 2026, for a voluntary interview with Paris prosecutors investigating his social media platform, X, and its AI chatbot, Grok.

French prosecutors confirmed that they had “taken note of the absence of the first people summoned,” without directly naming Musk.

Despite the no-show, prosecutors said the investigation would continue.