Shivon Zilis's testimony in Musk v. Altman trial reveals her notes documenting OpenAI strategy discussions and her undisclosed role managing communication between Musk and OpenAI leadership

Zilis testified under oath that she is the mother of four of Musk's children and worked on his 'entire AI portfolio: Tesla, Neuralink, and OpenAI' starting in 2017, working 80 to 100 hours a week. She served on OpenAI's board while her first two children by Musk—twins born in 2021—were kept secret from the board until Business Insider reported court documents naming Musk as the father.

Her meeting notes form the trial's most important evidence, documenting discussions among Brockman, Altman, Sutsekever, and Musk about creating a for-profit arm of OpenAI. The notes reveal Musk's funding freeze before OpenAI leadership knew about it (flagged August 20, 2017; announced by Musk September 1st) and proposals including staffing OpenAI's board with Musk associates and making OpenAI a subsidiary of Tesla.

Under cross-examination, Zilis could not adequately explain away the notes. An email showed she advised Musk on when he was 'in a good headspace' for conversations with Altman, and a text message revealed she resigned from the board after learning 'Elon is starting a competitive venture'—later referring to xAI—though she claimed not to recall that call at trial.

The testimony damaged Musk's case because her primary allegiance appeared to be to Musk rather than OpenAI, undermining her credibility on claims about OpenAI's mission during the period when Altman was fired and Microsoft negotiations occurred.