In doing so, OpenAI walked away from one of its most important customers. Cursor has long paid OpenAI fees to offer the ChatGPT-maker’s models to developers using its AI coding editor. At the start of 2026, Cursor was one of OpenAI’s top five customers in terms of revenue, people familiar with the matter tell WIRED.
By the spring of this year, OpenAI estimated Cursor would bring in more than $1 billion in annualized revenue for the ChatGPT maker, based on the partnership’s performance at that time, the people said. The figures, which have not been previously reported, indicate the financial loss OpenAI is willing to take on to avoid doing business with Musk. OpenAI declined to comment.
Representatives for SpaceX and Cursor did not immediately respond to WIRED's request for comment. As OpenAI prepares to go public next year, it’s trying to show investors a more stable business—ideally one that doesn’t rely so heavily on the goodwill of Musk. OpenAI reportedly now generates more than $40 billion in annualized revenue, drawing on several different lines of business, including subscriptions, ads in ChatGPT, and selling access to its AI coding tool, Codex.
Losing a major customer like Cursor may not hurt OpenAI financially as much as it once would have, but it was certainly a difficult decision. The company acknowledged in its blog post that ending the partnership may damage its standing with developers—a community it has spent years carefully working to win over—by cutting off a major channel they use to access OpenAI’s models. Michael Truell, Cursor’s founder and CEO, who is now leading teams at SpaceX, responded publicly to OpenAI’s announcement hours later on Friday in a post on X, claiming that the ChatGPT-maker’s models only “serve about 5% of Cursor user traffic.” The comment seemed designed to imply that OpenAI’s models weren’t very popular with developers using Cursor, and wouldn’t meaningfully affect its business.
OpenAI’s head of core products, Thibault Sottiaux, was quick to point out that token usage is “not a proxy for revenue nor value created,” and asked Truell to “share the math” behind the 5 percent number. WIRED previously reported that Cursor leaders hoped to remain a platform for third-party AI models from OpenAI and Anthropic, even after the SpaceX acquisition. Some AI insiders considered that wishful thinking, assuming that Cursor and OpenAI’s breakup has long been a foregone conclusion.
As OpenAI builds Codex into a large AI coding business, it increasingly finds itself competing with Cursor for customers. Nevertheless, the companies have operated relatively peacefully, as partners and competitors, for well over a year. Evidently, that arrangement was no longer possible with Musk in control of Cursor.
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