Elon Musk is seeking an enormous $79 billion to $134 billion in damages from OpenAI and Microsoft. He claims that the two companies reaped “wrongful gains” from his early role in founding and funding OpenAI in 2015.

Musk’s lawyer revealed details of the claim on Friday in a court filing. The case is set to go to trial in April in Oakland, California. 

Musk said in a post on X on Friday that he “can’t wait to start the trial.” “The discovery and testimony will blow your mind,” he wrote. 

Musk’s lawsuit argues that OpenAI and Microsoft have defrauded him by abandoning OpenAI’s original nonprofit mission to develop artificial intelligence “for the benefit of humanity.” Musk argues that OpenAI has instead built a tightly controlled, profit-driven ecosystem. 

Musk says his early backing of OpenAI, which included approximately $38 million in funding, as well as recruiting, credibility and key introductions, entitles him to a share of the company’s present value. He is also going after Microsoft’s AI gains. 

Musk is seeking damages in a range calculated as his share of the “wrongful gains” he alleges the two organizations realized due to his contributions, according to court filings. 

The damage numbers come from financial economist C. Paul Wazzan, who is serving as Musk’s expert witness. Wazzan’s analysis maps Musk’s entitlement to portions of OpenAI’s $500 billion valuation, calculating that Musk should receive $65.5 billion to $109.43 billion in “wrongful gains” from OpenAI. 

Wazzan also adds the value Microsoft captured through its deep integration of OpenAI models into products like Azure and Copilot, making a similar calculation that Microsoft should pay Musk $13.3 billion to $25.06 billion in “wrongful gains.” 

“Just as an early investor in a startup company may realize gains many orders of magnitude greater than the investor’s initial investment, the wrongful gains that OpenAI and Microsoft have earned — and which Mr. Musk is now entitled to disgorge — are much larger than Mr. Musk’s initial contributions,” Musk’s lawyer, Steven Molo, wrote in the filings, per Bloomberg. 

OpenAI has outright rejected Musk’s framing. In a statement shared with Bloomberg, the company called the claims “frivolous,” “not serious” and part of a broader harassment campaign intended to slow it down — a move that would boost Musk’s rival AI venture, xAI. The company has released internal communications arguing that Musk himself pushed for a for-profit structure, albeit one that he could control.

Both OpenAI and Microsoft maintain that Musk has no contractual right to damages, regardless of his contributions. 

Musk is the richest person in the world, with a net worth of $681 billion at the time of writing. He is worth about $400 billion more than Google co-founder Larry Page, the second-richest person in the world. 

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