Late Friday night, OpenAI announced in a blog post that it was ending its partnership with Cursor, the startup behind one of the most popular AI coding tools. The decision came after SpaceX acquired Cursor in a $60 billion deal, raising concerns at OpenAI about how its artificial intelligence models would be used under Elon Musk’s leadership.
By ending the agreement, OpenAI walked away from one of its most important enterprise customers. Cursor had paid OpenAI to provide ChatGPT models to developers using its AI-powered coding editor. People familiar with the matter told WIRED that Cursor ranked among OpenAI’s five largest customers by revenue at the beginning of 2026. Based on the partnership’s growth, OpenAI estimated that Cursor could generate more than $1 billion in annual revenue for the company by this spring.
The previously unreported estimate highlights the financial cost OpenAI is willing to accept to avoid doing business with Musk-controlled companies. OpenAI declined to comment, while representatives for SpaceX and Cursor did not immediately respond to WIRED’s requests for comment.
“We are making this choice because we have no confidence that SpaceX will use our technology within the scope of its terms of service, based on Elon Musk’s companies’ history of contract violations,” OpenAI said in its blog post.
OpenAI is preparing for a potential public offering next year and is working to present investors with a more stable, diversified business that is less dependent on individual partners. The company is currently reported to be generating $40 billion in annual revenue. Its business includes ChatGPT subscriptions, advertising, and access to its AI coding platform, Codex.
Although losing a major customer such as Cursor may have a smaller financial impact on OpenAI than it would have in the past, ending the partnership was still a significant decision. OpenAI acknowledged that the split could weaken its relationship with software developers, a community it has spent years cultivating. Cursor has served as one of the primary channels through which developers access OpenAI’s models.
Cursor founder and CEO Michael Truell, who now leads SpaceX’s team, responded publicly to OpenAI’s announcement several hours later on Friday. In a post on X, Truell claimed that OpenAI models accounted for only about “5% of Cursor user traffic.” The comment appeared intended to suggest that ending access to OpenAI models would have a limited effect on Cursor’s business and its developer customers.
Thibault Sottiaux, OpenAI’s head of core products, quickly challenged the claim, arguing that token usage is “not a substitute for revenue or the value created.” Truell responded by asking OpenAI to share the calculations behind its 5% figure.
WIRED previously reported that Cursor executives hoped to continue offering third-party AI models from OpenAI and Anthropic after the SpaceX acquisition. Some industry insiders viewed that expectation as unrealistic and believed a breakup between Cursor and OpenAI was inevitable. As OpenAI expands Codex and builds a broader AI coding business, it is increasingly competing with Cursor for developers and enterprise customers. Even so, the companies had operated as both partners and competitors for more than a year without major public conflict.
That arrangement became more difficult once Musk gained control of Cursor. OpenAI may have concluded that continuing the partnership was not worth the risk of SpaceX gaining access to its most advanced AI models. In its blog post, OpenAI also referenced Musk’s apparent statement earlier this year that xAI, now part of SpaceX, had used OpenAI models to train its own systems. The statement reportedly came during Musk’s deposition in a lawsuit against OpenAI, in which Sam Altman and Greg Brockman accused Musk of attempting to take control of the nonprofit they co-founded nearly a decade ago. A federal jury dismissed the case earlier this year.
Source: www.wired.com