OAKLAND, CALIFORNIA — Elon Musk's civil trial against OpenAI, Sam Altman, and Greg Brockman opened Monday in the U.S. District Court for the Northern District of California in Oakland, where Musk alleged the defendants reneged on the company's founding agreement by prioritizing profit over a promise to remain a nonprofit dedicated to human progress. The trial is expected to last about four weeks.

The lawsuit, filed in 2024, names Altman, Brockman, and Microsoft as defendants and includes claims of breach of charitable trust and unjust enrichment. Musk is seeking to remove Altman from OpenAI's board and is also seeking billions of dollars in wrongful gains to fund OpenAI's non-profit arm. If he wins, it could derail OpenAI's plans for an initial public offering. OpenAI is now valued at more than $85 billion.

Musk contributed $38 million in funding to OpenAI from December 2015 through May 2017. "I was a fool who provided them free funding to create a startup," Musk, the founder of Tesla and SpaceX, said from the witness stand. "I could have done that with OpenAI, but I chose not to. I deliberately chose to create this as a non-profit for the public good," he said.

He testified he initially sought a majority stake in OpenAI and control of four out of seven board seats, but expected this would be diluted as the company grew. He compared this to his stake in Tesla, which he said is now around 15%, down from a majority stake when the company was founded over two decades ago.

A lawyer questioned Musk about emails he wrote before OpenAI's founding in 2015, including whether it should be a standard for-profit company and whether his donations qualified for tax deductions. "Your questions are not simple. They are designed to trick me essentially," he said. When Judge Yvonne Gonzalez Rogers asked whether OpenAI was formed as a nonprofit in December 2015, Musk said yes but added it was not always simple, comparing the question to asking "Have you stopped beating your wife?"

He said his views on Altman and his OpenAI cofounders moved through three phases: initial excitement, losing confidence, and a late 2022 period when he concluded they were betraying their promise. "Wait a second, these guys are betraying their promise," he said. After OpenAI raised $10 billion from Microsoft in 2023, Musk sent Altman a text message that read, "What the hell is going on? This is a bait and switch."

According to court documents, Shivon Zilis, then a board member of OpenAI, texted Musk asking whether she should stay "close and friendly" with OpenAI to "keep info flowing." Musk replied, according to the documents, "Close and friendly. But we are going to actively try to move three or four people from OpenAI to Tesla."

OpenAI lawyers have rejected the allegations, stating the company leaders never promised it would remain a nonprofit forever. The company has argued that the legal challenge is aimed at undercutting its rapid growth and bolstering Musk's competitor xAI, the maker of the chatbot Grok, which he launched as a for-profit company in 2023.