Walter Isaacson, biographer of Elon Musk, says the Tesla (NASDAQ:TSLA) billionaire has a look he reserves for Sam Altman, and it isn’t pretty.

“I just watched his face as he went into what we sometimes called ‘demon mode’ every time he talked about how he felt betrayed by Sam Altman,” Isaacson told Squawk Box Tuesday.

How The Feud Started

Musk and Altman co-founded OpenAI in 2015. The premise was simple: build an AI lab that was open source and nonprofit, a direct counterweight to Google’s dominance in the field.

Altman later changed that, converting OpenAI into a for-profit entity. For Musk, who had been among the company’s earliest and most prominent backers, that was the original sin.

The Lawsuit

Musk filed suit against Altman in the U.S. District Court for the Northern District of California, alleging OpenAI abandoned its founding nonprofit mission.

Isaacson does not expect it to end quietly. “It’s not something we can just say, okay, it’s a little bit of money here or there, let’s divvy up the proceeds and go home,” he said.

The personal dimension, he argued, makes settlement close to impossible. This is not a standard contract dispute. It is a story about ideology, trust and a founding relationship that curdled into something much uglier.

What Prediction Markets Say

Bettors are not backing Musk. The Polymarket contract on whether he wins his case against Altman by December 31, 2026 sits at just 39%, on $93,126 in volume. It has ticked slightly upwards in recent weeks.

Kalshi has a similar contract, which is at 36% for Musk to prevail. This has seen $339,000 in volume.

Both charts are similar. Odds hovered near 55% through January and February before collapsing in early March.

On Altman

Isaacson offered a stark example of Altman's playbook in action. After Anthropic refused Pentagon demands to strip safety guardrails from its AI and lost the contract, OpenAI swooped in immediately. Altman offered his company as a replacement, promising no similar guardrails would get in the way.

“I think he was partly personal and partly business,” Isaacson said. “He just wanted to come in when Anthropic was losing its way with the Pentagon.”

Image: Shutterstock