Musk seeks up to $134 billion from OpenAI and Microsoft over early contributions

Elon Musk files federal court papers in Oakland seeking as much as $134 billion from OpenAI Inc. and Microsoft Corp., alleging the companies realized “wrongful gains” tied to his financial and non-monetary support during OpenAI’s 2015 founding. The complaint asks a jury to disgorge profits Musk’s legal team says are attributable to his early cash investment and seed-era assistance.

Musk’s filing sets out a damages range that varies by defendant. Using a model by financial economist C. Paul Wazzan retained by Musk, the complaint attributes wrongful gains to OpenAI of roughly $65.5 billion to $109.4 billion and to Microsoft of about $13.3 billion to $25.1 billion. Those ranges combine to roughly $78.8 billion to $134.5 billion and are commonly summarized as $79 billion to $134 billion, with the filing stating the case maxes out at $134 billion.

The suit frames Musk’s early stake as modest in dollar terms but foundational in value. Musk’s counsel says he provided about $38 million in early funding, which the filing describes as roughly 60 percent of OpenAI’s seed funding, and alleges he also provided recruitment help, technical and business advice, introductions to key contacts, and credibility that helped the project attract partners and talent. Wazzan’s damages model explicitly combines Musk’s initial cash investment with those non-monetary contributions to calculate the alleged wrongful gains. The complaint also indicates Musk may seek punitive damages.

At the center of the legal theory is Musk’s contention that OpenAI breached its founding mission when it restructured into a commercial entity and entered a close partnership with Microsoft, producing disproportionate commercial returns traceable to Musk’s early support. The filing characterizes those returns as subject to disgorgement on the theory that they were wrongfully realized from the founding contributions.

Procedurally, the filing was submitted Jan. 17 in federal court in Oakland. A judge in Oakland recently rejected a final bid by OpenAI and Microsoft to avoid a jury trial and ruled that a jury will hear the case. The trial is expected to begin in April 2026, with court scheduling indicating a late April start for the jury trial.

OpenAI has dismissed the suit as baseless and has characterized Musk’s legal campaign as part of ongoing harassment, and the company reportedly warned investors and partners to expect attention-grabbing claims as trial approaches. Microsoft has rejected allegations that it aided or abetted any wrongdoing and, along with OpenAI, has filed court briefs challenging Musk’s damages calculations.

The dispute revives long-simmering tensions from the origins of the AI nonprofit in 2015. Musk was a co-founder of OpenAI and left the organization in 2018. He launched a rival AI firm, xAI, in 2023, which operates a chatbot called Grok. The complaint follows prior legal skirmishes between Musk and OpenAI leadership beginning in 2024 over governance and the group’s move away from a purely nonprofit model.

Beyond its immediate financial stakes, the case could have broad implications for how courts treat early, nontraditional contributions to startups and for the structuring of research partnerships between nonprofit-startup hybrids and large corporate investors.