Elon Musk is suing OpenAI and its CEO, Sam Altman, over claims that the pursuit of profit has led the company to abandon its founding mission to develop artificial intelligence technology that will benefit humanity. In a lawsuit filed with a San Francisco court on Thursday, Musk alleges that OpenAI’s partnership with Microsoft has transformed the organization “into a closed-source de facto subsidiary” of Microsoft that’s focused on maximizing profits.

According to the lawsuit, such actions constitute a breach of the founding agreement between Musk — who co-founded OpenAI in 2015 but no longer retains a stake in the company — Altman, and OpenAI president Greg Brockman, who committed to making the project a nonprofit and its technology open source. These violations include keeping the design of OpenAI’s GPT-4 model a “complete secret,” with the suit claiming this decision was “primarily driven by commercial considerations, not safety” and that the GPT-4 model is now “a de facto Microsoft proprietary algorithm.”

The lawsuit seeks to force OpenAI to adhere to its founding agreement and “return to its mission to develop AGI for the benefit of humanity,” rather than benefiting Altman, Brockman, and Microsoft — “the largest technology company in the world.”

Musk has been critical of the risks that AI advancement could have on society prior to co-founding OpenAI, calling for safeguards to be put in place to prevent such systems from being used to replace humans. Last year, Musk and AI researchers signed an open letter calling for companies to pause “giant AI experiments.” He later opened his own AI company, xAI, and launched an AI bot inside of the social media platform X.

The lawsuit claims that the GPT-4 model OpenAI released in March 2023 isn’t just capable of reasoning but is also actually “better at reasoning than average humans,” having scored in the 90th percentile on the Uniform Bar Examination for lawyers. The company is rumored to be developing a more advanced model, known as “Q Star,” that has a stronger claim to being true artificial general intelligence (AGI).

Altman was fired (and subsequently rehired five days later) by OpenAI in 2023 over vague claims that his communication with the board was “hindering its ability to exercise its responsibilities.” The lawsuit filed by Musk alleges that in the days following this event, Altman, Brockman, and Microsoft “exploited Microsoft’s significant leverage over OpenAI” to replace board members with handpicked alternatives that were better approved of by Microsoft.

“The new Board members lack substantial AI expertise and, on information and belief, are ill equipped by design to make an independent determination of whether and when OpenAI has attained AGI — and hence when it has developed an algorithm that is outside the scope of Microsoft’s license,” claims the lawsuit. The partnership between OpenAI and Microsoft is currently being examined by regulators in the UK, EU, and US to assess if their shared relationship impacts competition.