Elon Musk's Lawsuit Against OpenAI Continues with Greg Brockman's Testimony on $30 Billion Stake

The trial between Elon Musk and OpenAI entered its second week on Monday, May 4, 2026, with OpenAI president Greg Brockman taking the stand in a federal courtroom in Oakland. Brockman confirmed his personal stake in OpenAI is worth roughly $30 billion. Musk's counsel questioned Brockman for two hours, returning to the $30 billion figure more than a dozen times.

The case is being argued before Judge Yvonne Gonzalez Rogers. The trial opened on April 28, 2026. Judge Gonzalez Rogers has bifurcated the proceedings into a liability phase and a separate remedies phase.

The liability phase is expected to conclude around May 21, 2026. A nine-person jury sits during the liability phase only, and the jury's verdict is advisory. Structural remedies fall solely to Judge Gonzalez Rogers.

The trial is expected to run another two to three weeks from May 5, 2026. Sam Altman has not yet testified in the trial as of May 5, 2026. Microsoft chief executive Satya Nadella is expected to testify.

Stuart Russell, a Berkeley computer scientist, will appear as Elon Musk's expert on AI risk. Judge Yvonne Gonzalez Rogers declined a request from Musk's counsel that Stuart Russell be permitted to range beyond his written report into extinction scenarios. Two days before the trial began on April 28, 2026, Elon Musk texted Greg Brockman to gauge interest in settlement.

Greg Brockman proposed mutual dismissal in response to Elon Musk's text. Elon Musk replied to Greg Brockman that he and Sam Altman would be the most hated men in America by week's end. Judge Yvonne Gonzalez Rogers declined to admit the text exchange between Elon Musk and Greg Brockman.

Elon Musk sued OpenAI and Sam Altman in 2024. The original complaint by Elon Musk contained twenty-six claims. Two claims survive in the lawsuit: breach of charitable trust and unjust enrichment. The fraud claims in the lawsuit were dismissed before trial.

Microsoft is named as a co-defendant in the lawsuit for allegedly aiding and abetting the breach. Elon Musk seeks to unwind OpenAI's for-profit structure and return its assets to the nonprofit foundation.

Elon Musk seeks up to $150 billion in damages from OpenAI and Microsoft combined. Any damages award would flow directly to OpenAI's charitable arm. A finding that the 2019 capped-profit conversion breached a charitable trust would force a reorganization placing the nonprofit foundation back in control.

The 2025 successor to the 2019 capped-profit conversion is part of the case. Elon Musk's complaint seeks the removal of Sam Altman and Greg Brockman. OpenAI's lead counsel William Savitt stated that Elon Musk supported a for-profit restructuring as early as 2017 as long as he was placed in charge.

The defense argues the lawsuit is a delayed instrument of competitive harm. Elon Musk predicted OpenAI's failure after leaving. Elon Musk launched a competitor to OpenAI after leaving. Elon Musk co-founded OpenAI in late 2015 as a nonprofit.

Elon Musk contributed roughly $38 million to OpenAI in its early years. Elon Musk left the OpenAI board in 2018. OpenAI created a capped-profit subsidiary in 2019. Microsoft invested more than $13 billion in OpenAI.

OpenAI has received larger commitments from Amazon, SoftBank, and Nvidia. ChatGPT launched in November 2022. OpenAI was preparing for an initial public offering in 2025.