OpenAI Cuts Off SpaceX-Owned Cursor, Escalating Its War With Elon Musk

OpenAI told on Friday that it plans to stop supplying AI models to Cursor, the popular AI coding tool built by Anysphere and recently acquired by Elon Musk’s SpaceX, with a proposed shutoff date of November 12, 2026.

The decision marks the latest flashpoint in the long-running feud between OpenAI CEO Sam Altman and Musk, OpenAI’s co-founder turned rival.

Against that backdrop, the move comes despite OpenAI’s nearly four years of close collaboration with Cursor’s team. OpenAI says the cutoff isn’t about anything Cursor did wrong, but about whether its new owner can be trusted to follow the rules.

OpenAI Points to a Pattern, Not a Single Violation

OpenAI said it is ending the deal “based on our experience with Elon Musk’s companies violating contracts.”

The company pointed to Twitter, now part of SpaceX, which it says violated its OpenAI contract after Musk’s 2022 takeover. It also cited sworn testimony from Musk earlier this year acknowledging that SpaceX’s xAI had violated OpenAI’s terms of service.

OpenAI described the decision as a compliance measure tied to its upcoming Astra model, not a competitive move. 

Its agreement with Cursor allows cancellation within a limited window after a change in ownership, and OpenAI chose the maximum notice period rather than ending access immediately.

Cursor’s Team Says It’s Trying to Work Things Out

According to Reuters, Michael Truell, Cursor’s co-founder and now an executive at SpaceX, responded on X the same day, saying Cursor’s team is speaking with OpenAI to try to resolve the issue. 

He noted that Cursor was among OpenAI’s earliest users and said the company has “trusted their platform to be neutral infrastructure for our business.” 

That reliance shows how central OpenAI’s models have been to Cursor’s product, which also offers SpaceXAI’s Grok models alongside options from Anthropic and Google.

Reuters reported that SpaceX did not immediately respond to a request for comment on the decision, leaving Cursor’s next move, and how it plans to serve developers currently relying on OpenAI’s models, unresolved for now.

A Familiar Playbook, Aimed at a Familiar Rival

This isn’t the first time a major AI lab has pulled model access after an ownership change.

Anthropic did something similar to Windsurf last year when the company was rumored to be headed for an OpenAI acquisition, cutting direct access to its Claude within days and forcing Windsurf to find alternative compute.

What makes OpenAI’s move against Cursor different is the timeline and the buyer. 

OpenAI is using the maximum contractual wind-down period rather than reacting within days, while the buyer is Musk, with whom OpenAI remains legally entangled following a 2024 lawsuit that went to trial in April 2026 and ended with a May jury verdict against Musk.

The move suggests OpenAI is using a contractual off-ramp to avoid indirectly supporting a competitor run by its most litigious critic, while giving Cursor developers until November 12 to find alternatives before access ends.

Source: Our decision on Cursor following its acquisition by SpaceX