'Unserious demand' vs. 'wrongful gains': Musk and OpenAI trade blows over $134 billion

Billionaire Elon Musk is seeking up to $134 billion from ChatGPT operator OpenAI and Microsoft, claiming he is entitled to the "wrongful gains" that they accrued from his early support, according to a court filing on Friday.

Musk stated in a federal court filing ahead of his trial against the two companies that OpenAI gained between $65.5 billion and $109.4 billion from his contributions while co-founding the startup from 2015 onward, while Microsoft profited between $13.3 billion and $25.1 billion from the partnership. 

"Without Elon Musk, there'd be no OpenAI. He provided the bulk of the seed funding, lent his reputation and taught them all he knows about scaling a business. A pre-eminent expert quantified the value of that," Musk's lead trial lawyer Steven Molo said in a statement to Reuters.

In a statement, OpenAI dismissed Musk's claim as an "unserious demand" by Musk and part of what it said was his "harassment campaign" against the company.

Microsoft did not respond to a request for comment on the amount of compensation sought by Musk.

Microsoft and OpenAI also file suits

During the week, OpenAI called the lawsuit "baseless" and part of a "harassment" campaign by Musk. A Microsoft lawyer has said there is no evidence that the company "aided and abetted" OpenAI.

The two companies challenged Musk's damages claims in a separate filing on Friday.

Musk, who left OpenAI in 2018 and runs xAI with its competitor chatbot Grok, alleges that OpenAI violated its founding mission in a high-profile restructuring to a for-profit entity.

A judge in Oakland, California, ruled this month that the case will go before a jury, with the trial expected to begin in April.

Musk's filing stated he contributed about $38 million – roughly 60 percent of OpenAI's early seed funding – helped recruit staff, connect the founders with contacts and lend credibility to the project when it was created.

"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 filing argues.

The filing says Musk's contributions to OpenAI and Microsoft were calculated by his expert witness, financial economist C. Paul Wazzan.

If the jury finds either company liable, Musk may seek punitive damages and other penalties, including a possible injunction, though the filing did not specify its possible form.

In their own filing, OpenAI and Microsoft asked the judge to restrict what Musk's expert may present to jurors, calling his analysis "made up," "unverifiable" and "unprecedented" and seeking an "implausible" transfer of billions from a nonprofit to a former donor turned competitor.

The companies also disputed Musk's damages figures more broadly, saying the expert's approach is unreliable and could mislead the jury.