Sam Altman’s OpenAI has announced it is ending developer access to its models on Cursor, the popular coding assistant that Elon Musk’s SpaceX acquired earlier this month. The AI rivals have been locked in a bitter feud for a decade.
CNBC reports that OpenAI set a proposed shutoff date in November and said it won’t supply Cursor with any future models as the agreement winds down. According to financial filings, SpaceX completed its $60 billion acquisition of Cursor on August 14.
OpenAI models account for roughly 5 percent of Cursor’s user traffic, Cursor CEO Michael Truell said in a post on X Friday night. “OpenAI models serve about 5% of Cursor user traffic, and we’re speaking with the OpenAI team to resolve this. Cursor was one of the very first users of OpenAI, we’ve worked closely with their team for years, and we’ve trusted their platform to be neutral infrastructure for our business,” Truell wrote.
OpenAI framed the decision as a matter of trust. “We are making this choice because we cannot be confident that SpaceX will use our technology within our terms of service, based on our experience with Elon Musk’s companies violating contracts,” the company said in its announcement. Cursor and OpenAI did not immediately respond to CNBC’s requests for comment.
Musk answered on X Saturday with a dismissive jab at OpenAI’s leadership. “I couldn’t care less. Scam Altman and Greg Stockman are utterly untrustworthy,” he wrote, repeating a longstanding accusation that OpenAI “stole an open source nonprofit.” He has made a similar claim in court, accusing the company of “stealing a charity.”
The clash goes back a decade. Musk co-founded OpenAI as a nonprofit research lab in 2015 and helped fund it in its early years. He left the board in 2018 after disputes over hiring talent away from the company, halting promised donations, and clashing with other board members. After his exit, OpenAI released ChatGPT, partnered with Microsoft, restructured into a for-profit company under a nonprofit parent, and raised substantial funding. Musk sued OpenAI along with Sam Altman and Greg Brockman in 2024, lost the case earlier this year, and has said he will appeal.
Cursor’s acquisition is the latest in a string of deals around Musk’s companies. SpaceX had already acquired both X and xAI in February, before going public in June.
OpenAI, meanwhile, is reportedly preparing its own public offering for next year. Rival Anthropic has held preliminary talks with bankers about a possible IPO this year, with a valuation that could reach as high as $2 trillion, according to CNBC’s prior reporting.
Anthropic has cut off developer access before: last June, it blocked the coding tool Windsurf from using its Claude models. But its relationship with Cursor is heading a different direction. Anthropic is now partnering with SpaceX and renting compute capacity from Musk’s company, and it plans to keep supplying Cursor with Claude models even under new ownership.
The future of AI in part will be determined by the battle between industry titans like Elon Musk and Sam Altman. Breitbart News social media director Wynton Hall has written his instant bestseller Code Red: The Left, the Right, China, and the Race to Control AI to serve as the definitive guide on how the MAGA movement can create positions on AI that benefit humanity without handing control of our nation to the leftists of Silicon Valley or allowing the Chinese to take over the world.
Read more at CNBC here.
Lucas Nolan is a reporter for Breitbart News covering issues of AI, free speech, and online censorship.