Elon Musk is seeking up to $134 billion in damages from OpenAI and Microsoft, arguing that the companies benefited from “wrongful gains” tied to his early backing of the AI startup, according to a court filing submitted on Friday.
In the filing, Musk said OpenAI gained between $65.5 billion and $109.4 billion from his contributions during its early years, while Microsoft gained between $13.3 billion and $25.1 billion. The claims were made ahead of a jury trial against both companies, which is expected to begin in April following a ruling this month by a federal judge in Oakland, California.
OpenAI, Microsoft and Musk’s legal teams did not immediately respond to requests for comment outside regular business hours. OpenAI has previously described the lawsuit as “baseless” and part of a harassment campaign by Musk, while a Microsoft lawyer has said there is no evidence the company “aided and abetted” OpenAI in any wrongdoing. In a separate filing on Friday, the two companies formally challenged Musk’s damages calculations.
Musk, who co-founded OpenAI in 2015 but left the organization in 2018, now runs rival AI firm xAI, which develops the chatbot Grok. He alleges that OpenAI violated its original nonprofit mission by restructuring into a for-profit entity and commercializing its technology, including ChatGPT.
According to the filing, Musk contributed about $38 million—roughly 60% of OpenAI’s early seed funding—while also helping recruit staff, connect founders with influential contacts, and lend credibility to the project in its formative stages. His legal team argues that, much like an early startup investor, he is entitled to gains far exceeding his initial investment.
The damages estimates were calculated by Musk’s expert witness, financial economist C. Paul Wazzan. Musk may also seek punitive damages and other remedies, including a possible injunction, if a jury finds either OpenAI or Microsoft liable, though the filing did not specify what form such an injunction might take.
In their own submission, OpenAI and Microsoft asked the judge to limit or exclude Wazzan’s testimony, calling the analysis “unverifiable,” “unprecedented,” and “implausible.” They argued that the proposed transfer of billions of dollars from a nonprofit organization to a former donor who is now a competitor would mislead jurors and rests on unreliable assumptions.
