OpenAI to sever AI model supply to SpaceX-owned Cursor, deepening Musk feud

OpenAI has announced it will discontinue providing its AI models to Cursor, the coding-tool company recently acquired by Elon Musk's SpaceX. The decision, revealed on Friday, marks a significant escalation in the long-running rivalry between OpenAI CEO Sam Altman and Musk.

In a blog post, OpenAI explained the move, stating, "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 also noted that X, formerly Twitter and now part of SpaceX, had previously breached its contract terms after Musk acquired the platform.

Musk responded on X early Saturday with a dismissive post: "I couldn't care less." He reiterated his criticism of Altman and OpenAI President Greg Brockman, calling them "untrustworthy" and repeating his claim that they "stole an open source nonprofit."

The feud between the two tech leaders has a long history, culminating in a federal trial earlier this year over Musk's $150 billion lawsuit against OpenAI. Musk had accused the company of betraying its original nonprofit mission. A jury ruled against Musk, determining he had filed the case too late.

Despite the tension, Michael Truell, a co-founder of Cursor and now an executive at SpaceX, said on X that the company is in discussions with OpenAI to resolve the issue.

Meanwhile, Anthropic, a rival AI firm with an existing partnership with SpaceX, announced it would increase compute support for its Claude models within Cursor. Tom Brown, a co-founder of Anthropic, confirmed the plan hours after OpenAI's announcement.

OpenAI stated it has proposed a shutoff date of November 12, 2026, citing a clause in its agreement with Cursor that allows for contract cancellation following a change of control. SpaceX completed its $60 billion all-stock acquisition of Anysphere, Cursor's parent company, earlier this month.