OpenAI Calls Musk's Expanded Lawsuit Demands a Legal Ambush Before Trial

OpenAI filed a late-night brief accusing Elon Musk of staging a "legal ambush" by dramatically expanding his lawsuit's demands just weeks before jury selection opens April 27 in a federal courthouse in Oakland. The filing, submitted Friday evening, said Musk's revised objectives were aimed at "sandbagging the defendants and injecting chaos into the proceedings, while trying to recast his public narrative about his lawsuit." The trigger was a separate Tuesday motion from Musk's legal team that proposed, for the first time, removing OpenAI CEO Sam Altman and President Greg Brockman from their officer roles as part of the requested remedies.

The lawsuit, which Musk filed in February 2024, seeks between $79 billion and $134 billion in what his attorneys call "wrongful gains" captured by OpenAI and Microsoft after OpenAI's transformation from a nonprofit into a commercial enterprise. If a jury were to award the full amount, it would rank among the largest court verdicts in U.S. history.

Musk, who co-founded OpenAI with Altman and others in 2015 but left its board in 2018 after reportedly attempting to merge the nonprofit with Tesla, originally contributed approximately $44 million to the organization. His legal team's damages methodology applies the percentage of OpenAI's early value that his contributions represented to the company's current multi-billion-dollar valuation to arrive at the claimed range. In a post on X, Musk stated that any proceeds from a legal victory would be donated to charity; his attorneys echoed that position in filings, stating that Musk seeks "to return all ill-gotten gains, including Microsoft's, to the OpenAI charity."

OpenAI's attorneys responded that the push to oust Altman and Brockman was a theory that had never appeared in the litigation record, and that introducing it now would require new documentary evidence and witnesses, complicating the court calendar just as both sides prepare to go before U.S. District Judge Yvonne Gonzalez Rogers of the Northern District of California.

The case had already survived a significant legal test. On January 15, 2026, Judge Gonzalez Rogers denied OpenAI's motion for summary judgment, citing a trove of evidence that included handwritten diary entries by Brockman himself, uncovered through 2025 discovery. One entry, written in 2017, read: "I cannot believe that we committed to non-profit if three months later we're doing b-corp then it was a lie." A second stated: "This is the only chance we have to get out from Elon." The judge concluded there was "ample evidence in the record" and that "triable issues of fact exist for a jury to decide."

At the summary judgment hearing, Judge Gonzalez Rogers told OpenAI's attorney William Savitt directly that she did not agree there was insufficient evidence to bring Musk's fraud and unjust enrichment claims to trial. Microsoft's attorney Russell Cohen argued the company lacked knowledge of any alleged wrongdoing; that motion was also denied, keeping Microsoft as a co-defendant.

The outcome carries implications far beyond the immediate parties. A damages award in the $79 billion to $134 billion range, or court-ordered governance remedies, could reshape legal expectations around nonprofit-to-for-profit conversions, founder protections, and the accountability of major strategic partners in the AI sector. How Judge Gonzalez Rogers handles Musk's eleventh-hour expansion of remedies, and whether the Brockman diary entries ultimately move a jury, will define the trial's gravitational pull on the broader industry.