OpenAI CEO Sam Altman at the Helion Energy blog is taking a closer look at Musk’s case on Capitol Hill.
Sam Altman faced direct questions Tuesday about his financial relationship with Helion Energy, an Everett, Wash., startup that aims to give more power to both OpenAI and Microsoft to power future data centers with artificial intelligence.
Testifying in Musk v. Altman in Oakland, the CEO of OpenAI confirmed under questioning that he owns about one-third of Helion, a stake worth about $1.65 billion by the end of 2025, according to financial disclosures in the case.
Altman, who left Helion’s board in March, said he has been backing away from OpenAI’s involvement with the fusion company. Asked by Musk’s attorney Steven Molo to explain what that actually means, Altman said it includes “the decision to proceed and the final approval of the terms.”
He noted that OpenAI has never purchased or received power from Helion but said the 2024 deal is “a way for us to have an opportunity to do that in the future.” Altman said he was aware of the second agreement in March 2026 but did not know its details.
He admitted that a “huge percentage” of his time at OpenAI is spent on sourcing and computing resources, which he previously did when he was chairman of Helion’s board.
Helion has separately agreed to sell power from the first commercial fusion plant, which is being built in central Washington, to Microsoft starting in 2028. Microsoft, OpenAI’s long-time partner and one of its biggest investors, is also a defendant in the case.
It was part of Musk’s attorney’s broader argument that Altman used his position at OpenAI to increase the value of his personal investment. Financial disclosures in the case showed that Altman has more than $2 billion in shares in companies that do business with OpenAI.
Musk alleges in the lawsuit that Altman and other OpenAI leaders received his donations to found OpenAI as a nonprofit before turning it into a for-profit business, enriching themselves. OpenAI and Microsoft, which is also a defendant, denied that Musk supported the change and sought joint control of the company.
Molo also pressed Altman for his role in negotiating the $200 million data deal between OpenAI and Reddit while holding a majority stake in the social media company. Altman said that the agreement was canceled due to mediation and he was threatened with legal action.
Questions of conflict of interest extend beyond the courtroom.
The House Oversight Committee sent Altman a letter on May 8 requesting documents related to OpenAI’s handling of potential conflicts, citing the Helion relationship specifically.
In the letter, the Oversight Committee said it wants to make sure that “funds donated for charitable purposes are not diverted for unintended uses, such as automatically increasing the market value of other companies in which an executive or board member may have an interest.”
A group of Republican state lawmakers has separately asked the SEC to consider the matter ahead of OpenAI’s planned IPO, the Wall Street Journal reported.
In a statement sent to GeekWire, a Helion spokesperson called Altman a longtime champion of the company and expressed gratitude for his support, leadership and investment.
“As Sam has shared, he has withdrawn from a potential deal between Helion and OpenAI,” the spokesperson said. “Additionally, Sam stepped down from the board in March to allow the companies to explore future partnerships to deliver zero-carbon, sustainable electricity to the world.”
Helion is not the only local company caught up in this issue. The WSJ also reported that Altman last summer approached Kent, Wash.-based rocket maker Stoke Space about working with OpenAI on data centers in space. Altman is an investor in Stoke through his family office.
Helion, founded in 2013, develops technology to generate electricity from nuclear fusion, the process that powers the sun. Neither company has shown that fusion can produce commercial power, but Helion has raised more than $1 billion from investors and broke ground last summer on its first plant in Malaga, Wash.
Altman has been one of the company’s biggest backers, personally investing $375 million in a $500 million round in 2021 and joining as chairman of the board in 2015, shortly after recruiting the company to the Y Combinator accelerator.
Helion’s questions were part of a broader day on Altman’s stand. He also parted ways with Musk’s lawyer over allegations of disloyalty to former colleagues and defended his decision to return to OpenAI after he was fired by the board in November 2023 – saying he was “willing to go back into a burning building” to try to save the company and its work.
GeekWire reported on today’s proceedings via a live stream of court audio. Updated after publication with Helion’s statement.
