Content Advisory: This article discusses fertility, sperm donation, and private family matters raised in court testimony. Reader discretion is advised.
Elon Musk’s legal fight with OpenAI and Sam Altman was already one of Silicon Valley’s messiest courtroom battles. Then Shivon Zilis took the stand.
Zilis, a former OpenAI board member and the mother of four of Musk’s children, testified Wednesday in federal court in Oakland, California, as part of Musk’s lawsuit over OpenAI’s shift toward a for-profit structure. Her testimony was expected to matter because of her past roles across OpenAI, Tesla, and Neuralink. Instead, the hearing also put Musk’s private family arrangements into the public record.
Why Elon Musk Is Suing OpenAI
The case centers on a bitter fallout between two of the biggest names in tech: Musk and OpenAI CEO Sam Altman.
Musk co-founded OpenAI nearly a decade ago, back when the company was set up as a nonprofit. He left the venture in 2018 and later launched his own artificial intelligence company, xAI, which now competes with OpenAI’s ChatGPT.
Musk claims he was misled into donating millions of dollars to OpenAI when it was still presented as a nonprofit project. He is suing Altman, OpenAI, co-founder Greg Brockman, and Microsoft. He wants the court to award $150 billion in damages, block OpenAI’s transition into a for-profit company and remove Altman from the board.
Altman’s side sees it very differently. OpenAI has argued that Musk is trying to damage a rival after failing to keep control of the company.
That is where Zilis becomes important. She joined OpenAI as an adviser in 2016 and later served as a director from 2020 to 2023. OpenAI lawyers have suggested she passed information to Musk after he left the company.
Shivon Zilis Says Musk Offered To Donate Sperm
Zilis told the court that Musk offered to help her have children in 2020.
“I still really wanted to be a mum and Elon made the offer around that time and I accepted,” she said.
She said Musk was encouraging people around him to have children at the time. “He was encouraging everyone around him at that time to have kids and he’d noticed I did not,” Zilis testified. “He offered to make a donation.”
Zilis said she and Musk had a “one-off” romance about a decade ago, but were not romantically involved in 2020 when the offer was made.
She also said health issues had changed her original plan of marrying and having children with a romantic partner.
Musk’s Paternity Was Kept Confidential
Zilis said she and Musk initially agreed to keep his paternity “strictly confidential.” That agreement, she testified, was why she did not tell Altman that the twins she gave birth to in 2021 were fathered by Musk.
She said she later told Altman in 2022, after learning a report about Musk’s paternity was expected.
Today, Zilis said Musk is involved in the lives of their four children. She testified that they spend a few hours a week together as a family.
Despite the personal disclosure, Zilis said Altman and Brockman wanted her to remain on OpenAI’s board. She said the three stayed friends until at least 2023. Brockman said earlier this week, “We trusted her to keep the Elon conflict under control.”
The OpenAI Control Fight Gets More Complicated
Zilis’ testimony also touched on OpenAI’s early discussions about changing its corporate structure.
Court materials showed that as early as 2017, OpenAI leaders were discussing how to raise the huge funding needed to grow. Brockman and another co-founder, Ilya Sutskever, were reportedly considering a B Corp structure, a type of for-profit entity that also keeps a defined public mission.
Emails from Zilis showed that Musk wanted more control of OpenAI, including additional board seats. He also suggested that OpenAI could become part of Tesla, possibly as a B Corp subsidiary. Zilis wrote in one exchange that such a move would “solve the funding issue immediately.”
The deal never happened. According to an email shown in court, Altman, Brockman and Sutskever were firm that Musk should “not have control” of OpenAI’s work. Zilis left OpenAI’s board in March 2023 as Musk was launching xAI.
The trial was already about money, control and the future of artificial intelligence. Zilis’ testimony added another layer: private family arrangements, hidden conflicts, and the personal ties behind one of tech’s most expensive feuds.
