Sam Altman, CEO of OpenAI Inc., during a media tour of the Stargate AI data center in Abilene, Texas, USA, on Tuesday, September 23, 2025.
Kyle Grillot | Bloomberg | Getty Images
OpenAI sent a letter to its investors and banking partners on Thursday, warning that they can expect Elon Musk to make “deliberately outlandish and attention-grabbing claims” as the lawsuit against the AI Institute heads to trial in April.
The case marks a public escalation in Musk’s long-standing feud with OpenAI, and the company’s letter serves as an attempt to pre-empt and alleviate investor concerns. OpenAI has raised billions of dollars from venture capitalists, increasing its valuation to $500 billion.
Musk co-founded OpenAI as a nonprofit research company in 2015 with several other researchers and executives, including the startup’s CEO Sam Altman.
He filed suit in 2024, alleging that he was “relentlessly manipulated” and “deceived” by OpenAI after it sought to transform into a for-profit entity and established an “opaque web of for-profit OpenAI affiliates,” including a multibillion-dollar partnership with Microsoft.
Musk, who retired from OpenAI’s board in 2018, claims he owes “the value of all intellectual property developed” from his contributions, which could be in the billions of dollars, according to the complaint.
“We have a strong defense and are confident in our chances of success,” OpenAI said in a letter seen by CNBC. “In any event, based on the record to date, we believe this lawsuit is not worth more than the $38 million that Elon donated, but we cannot guarantee that.”
OpenAI declined to comment on the letter.
Earlier this month, U.S. District Judge Yvonne Gonzalez Rogers ruled that the case would proceed to trial. The lawsuit was filed in August 2024 in the U.S. District Court for the Northern District of California.
In the letter, OpenAI said it expected Musk to make comments about AI companies that were “not based in reality” and “typical of harassment tactics deployed in the past.”
“Mr. Elon’s lawsuit remains baseless and without merit. Our team is focused on ensuring that the jury understands these allegations as they are,” OpenAI said.
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