We knew Elon Musk's lawsuit against OpenAI's co-founders would cause fireworks when it came to trial. When Sam Altman took the stand, as the OpenAI CEO did Tuesday at the federal courthouse in Oakland, California, we knew he'd face allegations of being less than truthful.

We didn't know, however, that Altman would deploy a memory of Elon Musk showing off his favorite memes, to surprisingly strategic effect. Or that a "crossed fingers" emoji would gain new meaning.

Or, in probably the most dramatic moment of the trial, Altman would be confronted over whether he lied to the Senate when he said he had no financial stake in OpenAI.

Here are the four most memorable claims in a most consequential day in court:

1. Musk 'demotivated' OpenAI — and wanted it for himself

Altman first faced friendly questioning from OpenAI's lawyers, which allowed him to present his side of the narrative. This was his opportunity to tell the story of the ChatGPT maker's crucial early years, and how Musk contributed — which is to say, how much of a threat Musk's participation was to the nascent nonprofit.

"I don't think Mr. Musk understood how to run a good research lab," Altman said. "He had demotivated some of our most key researchers." How? By getting his co-founders to rank them by their accomplishments — known in Silicon Valley as "stack ranking" — then taking "a chainsaw" to the lower-ranked researchers.

In other words, the same play Musk used at Twitter, before it was X, in 2023, and at DOGE in 2025 — a practice so linked to him, he was literally presented with a chainsaw. "That did huge damage for a long time to the culture of the organization," Altman added.

Despite Musk being a "fairly mercurial" co-founder, Altman said, he was also interested in securing OpenAI for himself — or his heirs. In one "hair-raising moment," Altman said, Musk mused on whether "maybe OpenAI should pass to my children" if he died.

2. Musk was more interested in 'memes' than OpenAI's future

Altman then testified that he kept Musk fully updated on the company even after Musk left in 2018. But Musk was far from concerned about how OpenAI would fund the massive compute required, Altman said.

Altman described a 2018 meeting with Musk about the Microsoft funding Musk now says he abhors. But at the time, Musk was unusually full of "good vibes," Altman said, and had "a long, long conversation showing us memes on his phone."

The court's stenographer evidently had a hard time understanding Altman's use of "memes," which led to one of the most unintentionally humorous moments of the trial:

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The aforementioned emoji followed shortly after, and it too has a surprising amount of bearing on this case.

Altman narrated an email he'd written to Shivon Zillis, a former OpenAI employee with whom Musk has a romantic relationship and two children, that shows he was concerned how Musk would receive the Microsoft investment.

"Hopefully it's easy," he told Zillis, adding "crossed fingers emoji" for emphasis. And if Altman is to be believed, it was.

But therein lies the question that dominated the afternoon in court: is Altman to be believed?

3. 'Are you completely trustworthy?'

That was how Steven Molo, Musk's attorney, opened his cross examination of Altman. "I believe I'm a truthful person," Altman responded.

Molo tried to nail Altman down on the objective truth of his trustworthiness. But Altman wasn't biting, sticking only to what he said he "believes" about his own statements.

Molo also tried to get Altman on the record about a devastating profile of him, written by Ronan Farrow in the New Yorker, the gist of which is that Altman is a serial liar who was fired by OpenAI's board in 2023 for that reason.

But Altman's lawyer objected, the judge sustained the objection, and Molo was only able to alert the jury to the article's existence.

4. Altman's OpenAI stake under scrutiny

Molo was more successful when he suggested that Altman was being slippery about his financial stake — and not just in OpenAI.

Musk's attorney showed a slide with a list of companies that OpenAI does business with and that Altman had investments in, including Reddit. Some of the companies were acquired by OpenAI.

But that suggestion of self-dealing paled next to what Altman admitted next, for the first time ever: he has equity in OpenAI, albeit an indirect stake via the Silicon Valley startup incubator he used to run, YCombinator.

As Molo and online observers were quick to note, that appears to contradict Altman's sworn testimony in the U.S. Senate in 2023. "I have no equity in OpenAI," Altman told GOP Senator John Kennedy, insisting that he was only "paid enough for health insurance."

At the time, Kennedy offered some friendly advice to help the apparently selfless OpenAI chief get his due. "You need a lawyer," he told Altman.

Given that GOP members of the House Oversight Committee just launched a probe into Altman's financial dealings, Kennedy's advice hits different in 2026. Even after this trial is over, Altman's lawyers will have their work cut out for them.