OpenAI to End Cursor Access to Its AI Models After SpaceX 60 Billion Dollar Acquisition, Citing Musk

OpenAI announced Friday that it will end direct access to its AI models for the coding tool Cursor, citing concerns tied to the platform's recent acquisition by Elon Musk's SpaceX, in the latest flashpoint in the yearslong feud between OpenAI CEO Sam Altman and Musk.

SpaceX completed its 60 billion dollar acquisition of Cursor's parent company, Anysphere, on Aug. 14, according to financial filings, bringing the widely used AI coding platform into a Musk-controlled portfolio that already includes the social media platform X and the AI lab xAI, both of which SpaceX acquired earlier this year. OpenAI said in a post on X that its models will stop being directly available within Cursor on Nov. 12, describing the date as the maximum notice period allowed under its existing contract with the company.

"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," OpenAI said in its announcement, according to reporting from the outlet Tech Startups. The company added, "We know that the people most affected by this decision are the developers who rely on OpenAI models in Cursor. We care about their experience in this transition, and we're ready to go above and beyond to support them." OpenAI executive Thibault Sottiaux was more blunt in characterizing the rationale behind the move, telling reporters, according to The Decoder, "It boils down to trust."

Cursor CEO Michael Truell pushed back on the decision in a post on X late Friday, emphasizing the platform's long working relationship with OpenAI. "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. He noted that the practical impact of the cutoff is likely to be limited, saying, "OpenAI models serve about 5% of Cursor user traffic, and we're speaking with the OpenAI team to resolve this." OpenAI has said the relationship with Cursor's team dates back nearly four years, spanning almost the entirety of the company's existence.

Even with OpenAI's models representing a small share of overall traffic, developers who want to continue using OpenAI's technology within Cursor after the cutoff will still have options. According to reporting from TipRanks, users can bring their own OpenAI API key to continue accessing the models directly, or route requests through third-party cloud gateways such as Microsoft Azure or Amazon Bedrock. OpenAI has also said it will continue supporting its own IDE extensions that work alongside Cursor, according to The Decoder.

OpenAI's decision drew a pointed response from Musk. In a post on X on Saturday, Musk wrote, "I couldn't care less. Scam Altman and Greg Stockman are utterly untrustworthy," using derogatory nicknames for Altman and OpenAI President Greg Brockman before repeating his longstanding accusation that the two men "stole an open source nonprofit," according to CNBC's reporting on the exchange.

The dispute is the latest chapter in an increasingly personal and legally contentious rivalry between Musk and OpenAI's leadership. Musk co-founded OpenAI as a nonprofit research lab in 2015 and helped fund its early operations, but left the company's board in 2018 following disagreements over its strategic direction, its move to hire talent away from his own ventures, and his decision to cut off previously promised donations. Musk sued OpenAI, Altman and Brockman in 2024, alleging the organization had abandoned its founding nonprofit mission in favor of a more traditional, profit-driven corporate structure.

OpenAI has previously found itself on the receiving end of a similar cutoff from Musk. According to The Decoder, OpenAI had maintained a licensing agreement with Twitter worth roughly 2 million dollars annually, giving the company access to the platform's full tweet data feed to help train ChatGPT. When Musk discovered the arrangement after acquiring Twitter in December 2022, he determined the price was too low and terminated OpenAI's access, an episode OpenAI has referenced in explaining its wariness about SpaceX's ability to reliably honor contractual terms going forward.

Friday's move also follows a precedent set by a rival AI developer. In June 2025, Anthropic blocked the coding tool Windsurf from accessing its Claude models after reports surfaced that OpenAI was exploring a potential acquisition of that company, illustrating how ownership changes involving competing AI labs have increasingly prompted model providers to reassess access agreements with downstream coding platforms.

In the wake of OpenAI's announcement, Anthropic said it plans to increase computing capacity to support Cursor's continued use of its Claude models, positioning itself to expand its role as a primary AI provider for the platform. Cursor has also been working to reduce its reliance on any single external model provider, including through the development of its own in-house model, Composer 2.5, trained using more cost-efficient, open-weight technical foundations, according to TipRanks. SpaceX did not immediately respond to requests for comment on OpenAI's decision.