OpenAI co-founder discloses nearly US$30 billion stake, financial ties to Sam Altman

Published Tue, May 5, 2026 · 08:40 AM

[OAKLAND, California] OpenAI’s co-founder and president, Greg Brockman, on Monday (May 4) disclosed deeper financial ties to CEO Sam Altman than previously known, as well as a stake in the ChatGPT maker worth almost US$30 billion.

The details were shared in court during questioning by a lawyer for Elon Musk, who co-founded OpenAI and is now suing the company on grounds that it improperly became a for-profit company, abandoned charitable goals and should turn back into a non-profit.

Musk’s team said that Brockman’s independence was potentially compromised by financial incentives that led him to support Altman, the driver behind OpenAI’s reinvention as a for-profit company. Brockman also disclosed in court that he holds stakes in two startups backed by Altman as well as a percentage of Altman’s family fund.

The trial, in its second week in a California courtroom, could determine the future of OpenAI, which sparked a widespread craze over generative artificial intelligence after launching its ChatGPT chatbot in late 2022. Since then, OpenAI has raised well over US$100 billion from investors to hire researchers, buy computing power and expand the company ahead of a potential trillion-dollar IPO.

Musk is seeking the ouster of Altman and Brockman from leadership as well as US$150 billion in damages.

Brockman, early in his testimony, agreed that his stake in OpenAI was worth close to US$30 billion, a figure not previously known. In 2017, Altman gave Brockman a stake in Altman’s family office that was worth US$10 million at the time. That same year, Brockman, Musk and other OpenAI executives discussed restructuring OpenAI as a for-profit so the organisation could pay for the pricey computing power required to train AI systems.

2017 Compensation arrangement

Brockman said that he did not discuss his compensation directly with Musk. Emails read out in court showed that Altman mentioned the arrangement during a separate conversation with Jared Birchall, Musk’s head of family office, who relayed the details to Musk.

“One thing worth mentioning now is that he compensated Greg on the side by giving him a percentage ownership of Sam’s personal family office,” Birchall wrote in the e-mail, adding the deal could mean that “Greg is going to have a greater allegiance to Sam as a result of this arrangement.” Musk forwarded Birchall’s note to Brockman with two question marks.

When pressed on whether he was loyal to Altman, Brockman said, “I don’t know I would say it quite like that.”

Stakes in Altman-backed startups

On Monday, Brockman disclosed that he owned shares of AI chip startup Cerebras, including during various moments when OpenAI discussed buying the chipmaker. This year, OpenAI has said that it will spend a significant amount of money to buy Cerebras chips.

Brockman also said that he has a stake in Helion Energy, a fusion startup in which Altman has already invested hundreds of millions of US dollars. In March, Altman stepped down from Helion’s board because the two companies were looking to work together.

Musk, the world’s richest person, alleges OpenAI, Altman and Brockman secured his US$38 million in donations and personal help by promising to build a non-profit that would prioritise safe development of AI, before pivoting to create a for-profit entity to enrich themselves. His charges include breach of charitable trust and unjust enrichment.

OpenAI has said that Musk, the CEO of Tesla and SpaceX, is driven by a compulsion to control OpenAI and is bitter about the company’s success after he left its board in 2018. It has also been said that Musk did not prioritise safety issues while with the company, and that he is trying to bolster his own AI company, SpaceX unit xAI, which lags OpenAI in user adoption. REUTERS