OpenAI Trial Day — Altman Takes the Stand in Musk Lawsuit

CNBC reported Tuesday that OpenAI CEO Sam Altman is expected to take the witness stand at a federal courthouse in Oakland, California. His Sam Altman testimony follows that of OpenAI board chairman Bret Taylor, who returned to the stand Tuesday morning. The moment is among the most closely watched in the ongoing lawsuit brought by Elon Musk against OpenAI, Altman, and company president Greg Brockman.

Musk Claims OpenAI Abandoned Its Charitable Roots

Musk, who co-founded OpenAI with Altman and Brockman back in 2015, filed the lawsuit in 2024. He alleges the company broke its founding pledge to remain a nonprofit and pursue a public-benefit mission. Musk contends his roughly $38 million in early donations were used for purposes he never authorised. During his own time on the stand in the trial’s opening week, Musk accused both Altman and Brockman of self-enrichment. He repeatedly framed their conduct as an attempt to “steal a charity,” according to CNBC.

How Taylor’s Testimony Set the Stage

Taylor took the stand Monday afternoon to address questions about board governance and OpenAI’s corporate structure. He resumed testimony Tuesday before Altman was called. Altman is being presented as a witness by OpenAI’s own legal team rather than by Musk’s lawyers. That procedural distinction matters. It limits Musk’s counsel to cross-examining Altman only on topics raised during his direct examination. They cannot introduce entirely new lines of questioning.

Background: A Nonprofit Turned Commercial Giant

OpenAI launched in 2015 as a nonprofit research lab with backing from Musk, Altman, and other Silicon Valley figures. Over time it evolved into a capped-profit structure and began accepting large outside investment. That transformation is now at the heart of the legal dispute. Critics, including Musk, argue the shift betrayed the organisation’s founding principles. OpenAI counters that the structural change was necessary to fund frontier AI development at scale.

Congressional Scrutiny Adds Pressure on Altman

The trial is not the only source of pressure on the CEO this week. The House Oversight and Government Reform Committee sent Altman a letter Friday seeking details on how OpenAI manages potential conflicts of interest. Committee Chair Rep. James Comer cited disclosed financial ties between Brockman and ventures that Altman personally backs. Comer also flagged OpenAI’s proposed investment in Helion, a nuclear fusion startup in which Altman holds a personal stake. The committee has requested responses by May 22.

Additional OpenAI witnesses expected later this week include safety committee chair Zico Kolter and chief futurist Josh Achiam.

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