Shivon Zilis took the stand Wednesday in Elon Musk’s lawsuit against OpenAI, becoming the latest witness in a case that is forcing the company’s founding feud into the open. Zilis, a Neuralink executive and the mother of four of Musk’s children, was called as OpenAI argued that she had been part of a secret relationship with Musk while she worked with the company between 2016 and 2023.
The testimony put Zilis, 40, at the center of a dispute that is as much about relationships as it is about corporate control. OpenAI’s lawyers presented communications they said suggested she was working as an inside source for Musk after he left the company, including a 2018 text in which she asked whether she should stay close and friendly to OpenAI to keep information flowing or begin to disassociate. Musk replied that she should stay close and friendly, and said they were going to actively try to move three or four people from OpenAI to Tesla.
Zilis served on OpenAI’s board from 2020 to 2023 and met Musk through her work there. She later took on a role as project director at Tesla in 2017. In her testimony, she said she and Musk became romantically involved around 2016, and that the extent of that relationship was not publicly known until 2022, when Business Insider reported that she had twins with Musk the year before.
She also described a personal arrangement that has now become part of the court record. Zilis said she lives in a house in Austin where Musk sometimes stays when visiting their children, and that she decided to have children with him around the end of 2020 after he told her he would be happy to make a donation. When Musk took the stand last week, he referred to Zilis as the mother of his children and said he lives with her.
The texts shown in court added another layer to the dispute. A 2023 message from Sam Altman to Zilis asked whether it was a good idea for him to tweet something nice about Elon. OpenAI has used the communications to press its argument that Zilis was not just a board member or employee, but a link between Musk and OpenAI’s leadership.
The lawsuit itself is about control of the company’s future. Musk alleges that OpenAI’s leaders broke a founding agreement by restructuring the company from a nonprofit to a for-profit enterprise. OpenAI has argued that Musk supported the shift. The court filings and testimony have now raised the sharper question of whether Zilis was acting as an informant for Musk while working with OpenAI, a role that would deepen the split between the billionaire and the company he helped create.
What emerges from the witness stand is not just another clash over business strategy. It is a record of overlapping loyalties, intimate ties and internal messages that make the fight over OpenAI look less like a clean corporate dispute than a struggle over who was inside the room, and who was speaking for whom.