Elon Musk is asking a US court to award him as much as $134 billion from OpenAI and its key partner, Microsoft, claiming the companies profited enormously from his early backing of the artificial intelligence startup.
In a court filing submitted on Friday, Musk argued that OpenAI and Microsoft reaped what he called “wrongful gains” tied to his role as a co-founder and early supporter of OpenAI beginning in 2015. The filing comes ahead of a trial in which Musk is challenging the direction and governance of the AI company he helped launch.
According to the document, OpenAI’s valuation and related benefits surged by an estimated $65.5 billion to $109.4 billion as a result of Musk’s contributions in its formative years. Microsoft, which later became OpenAI’s most influential commercial partner, is alleged to have gained between $13.3 billion and $25.1 billion from that foundation, Musk said.
OpenAI has previously dismissed the lawsuit as “baseless,” accusing Musk of waging a campaign of “harassment” against the company. Microsoft has also pushed back, with one of its lawyers saying there is no evidence the company “aided and abetted” OpenAI.
In a separate filing submitted on Friday, OpenAI and Microsoft formally challenged Musk’s claims for damages, signaling that both companies intend to fight the case aggressively in court.
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Musk, who exited OpenAI in 2018 and now leads rival AI startup xAI, which operates the chatbot Grok, has argued that the company behind ChatGPT abandoned its original mission when it restructured into a for-profit entity.
The dispute is now headed to a jury. Earlier this month, a judge in Oakland, California, ruled that the case will go to trial, which is expected to begin in April.
In his latest filing, Musk said he invested roughly $38 million in OpenAI, accounting for about 60% of its early seed funding. He also claimed he played a hands-on role in the startup’s early days by helping recruit talent, introducing the founders to influential contacts, and lending his name and credibility to the project when it was first launched.
Musk argued, “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.”
The court papers say the value of Musk’s alleged contributions to both OpenAI and Microsoft was calculated by his expert witness, financial economist C. Paul Wazzan.
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The filing also notes that Musk could pursue punitive damages and other remedies if a jury finds either company liable, including the possibility of an injunction. It does not spell out what such an injunction would look like.
OpenAI and Microsoft, in their own submission, urged the judge to restrict what Musk’s expert is allowed to present to jurors. They argued that the analysis should be thrown out, calling it “made up,” “unverifiable” and “unprecedented,” and saying it rests on an “implausible” theory that would shift billions of dollars from a non-profit to a former donor who is now a competitor.
More broadly, the two companies challenged Musk’s damages claims, warning that the expert’s methodology is unreliable and could mislead a jury if it is allowed into evidence.