Musk vs. Altman: The Biggest Case in AI History Has Gone to Trial

Original | Odaily Planet Daily (@OdailyChina)

Author | Azuma (@azuma_eth)

The biggest case of the AI era has officially gone to trial.

On April 27, the case of “world's richest man” Elon Musk vs. “world's leading AI company” OpenAI officially entered the trial stage at the U.S. District Court for the Northern District of California. Jury selection began the same day, opening statements are expected to commence today, presiding Judge Yvonne Gonzalez Rogers, and the trial is expected to last four weeks.

A Look Back at the Grievances

The feud between Musk and OpenAI has a long history.

In 2015, Musk co-founded OpenAI with Sam Altman and others, both sharing the same idealism at the time — to create a “non-profit, open-source” AI organization to counter the AI monopoly of giants like Google. In the early days, Musk was even one of OpenAI's largest donors and played a key role on its board.

However, idealism soon ran into harsh realities. In its early years, OpenAI's AI development consistently lagged behind Google's DeepMind. Under the dual pressure of funding shortages and lack of progress, Musk grew increasingly dissatisfied with the OpenAI leadership led by Altman, even proposing to merge OpenAI into Tesla and take the helm as CEO to gain deeper control.

The leadership, including Altman, naturally rejected this. The final outcome was that Musk was pushed out of the OpenAI board in 2018, ending their partnership.

Subsequently, in March 2019, OpenAI officially abandoned its non-profit route, transitioning to a “capped-profit company.” Later that year, it accepted a $1 billion investment from Microsoft, accelerating its commercialization efforts.

2022 was another pivotal moment. OpenAI released the world-stunning ChatGPT that year, officially kicking off the LLM boom. Whether driven by his former idealism or simply unable to stand seeing his ex-colleagues thrive, Musk was reportedly furious (as media described at the time).

Afterwards, Musk fiercely criticized OpenAI on social media for abandoning its open-source, non-profit path, stating it was no longer “OPEN” and was fully controlled by Microsoft (notably, OpenAI has since announced terminating Microsoft's exclusivity rights)... He also founded xAI to compete head-on with OpenAI.

On the other hand, OpenAI believes Musk is simply “sour grapes.” OpenAI claims that back when Musk was on the board, he had expressed support for commercial transformation (supported by historical email evidence), only criticizing it after he left — arguing that the alleged deviation from its original mission is merely an excuse Musk uses because he lost control.

Day in Court

With mounting tensions, Musk formally filed a lawsuit against OpenAI and its two co-founders, Altman and Greg Brockman, in 2024.

First, in March 2024, Musk sued in a California state court — accusing OpenAI of violating its founding agreement by shifting from a “non-profit” to a “for-profit” entity, effectively becoming a “closed-source subsidiary” of Microsoft. He sought to compel OpenAI to return to its non-profit mission, open-source its core models, and prevent Microsoft from profiting.

This lawsuit was quickly dropped, appearing to be a probing move.

In October 2024, Musk refiled the lawsuit in the Northern District of California. This time, Musk added Microsoft to the list of defendants and escalated the allegations and demands — accusing OpenAI and Microsoft of fraud and misrepresentation (these charges were later dropped), unjust enrichment, breach of charitable trust, and conspiring to divert non-profit assets for commercial gain. He sought to block OpenAI's complete transition to a for-profit company, force it back to a non-profit structure, claw back illegal profits, demand damages of $134 billion to $150 billion, and remove Altman and Brockman.

In April 2025, OpenAI countersued Musk, alleging harassment and malicious interference with its operations, claiming Musk was deliberately trying to slow OpenAI's development for personal gain, marking the start of a bi-directional legal battle.

Then, in September 2025, Musk's xAI filed another lawsuit against OpenAI, accusing it of stealing trade secrets, partly because OpenAI hired former xAI employees to obtain confidential information. The next day, Musk posted on X: “We sent them many warning letters, but they continued to cheat. After exhausting all other avenues, legal action was the only option.”

Yesterday, this long-running saga finally made its way to the courtroom. With the trial phase underway, more details of the case are expected to be revealed over the next four weeks. While the possibility of further appeals by either side cannot be ruled out, the trial will undoubtedly clarify the key issues.

Heated Exchanges

With the trial commencing, Musk and OpenAI have also been trading heated barbs on social media.

Last night, Musk posted or retweeted dozens of messages, even resorting to personal attacks, calling Altman “Scam Altman” and Brockman “Greg Stockman.”

“Greg Stockman gave himself tens of billions of dollars in equity, and Scam Altman also helped himself to a share through a bunch of OpenAI-related deals structured like Y Combinator (and after this lawsuit, he'll directly get another tens of billions in equity)... I could have made OpenAI a for-profit company from the start, but I didn't. I founded it, funded it, recruited key talent, and taught them everything I knew about building a successful startup — all for the public good. Then they stole this charity.”

On the OpenAI side, while Altman and Brockman have not commented, OpenAI responded through official channels: “We can't wait to present our case in court because the truth and the law are on our side. This lawsuit was baseless and born of jealousy from the very beginning, intended to hinder a competitor. We will finally have the opportunity, before a California jury, to depose Musk under oath regarding his attempts to sabotage our work to ensure that general-purpose AI benefits all of humanity.”

Predicting the Outcome

Over the next four weeks of trial, several key figures, including Musk, Altman, Brockman, and Satya Nadella (Microsoft CEO), are expected to testify.

According to various media reports, key factors influencing the case's direction could include testimony from witnesses like Shivon Zilis (former OpenAI board member and mother of four of Musk's children), as well as physical evidence such as Brockman's personal diary (recording internal strategic thinking, submitted as evidence).

As for Judge Yvonne Gonzalez Rogers, appointed by former President Barack Obama, she is known for her pragmatic approach and has handled numerous major disputes between tech companies. In this case, Judge Rogers has broad discretion to determine whether any remedies are necessary and what they should be. She has divided the trial into two phases: Phase 1 to determine if Altman and OpenAI are liable for misconduct; Phase 2, if necessary, to determine the remedies.

With the trial underway, prediction markets like Kalshi and Polymarket have listed related events. Currently, the odds are roughly even (Musk's win probability is reported at 48%), pending further updates.

Looking ahead, this “biggest AI case” will not only adjudicate the historical grievances between Musk and Altman but will also directly or indirectly impact the subsequent IPO processes of two trillion-dollar valuation companies: OpenAI and SpaceX.

This is the largest non-technical variable in the current landscape of the AI race, one that could profoundly reshape the power structure of the future AI world.