OpenAI is terminating its contract with AI coding tool Cursor, effective November 12, 2026, following SpaceX’s acquisition of the company. The decision hinges on a clause in the agreement that gives OpenAI a limited window to end the partnership after a change in ownership — and the company isn’t being subtle about why it’s pulling the trigger.
“It boils down to trust,” said OpenAI’s Thibault Sottiaux. The statement points directly at Elon Musk, whose companies OpenAI says have a history of breaking contracts. The most cited example: a licensing deal that gave OpenAI access to Twitter’s full tweet data feed for roughly $2 million a year to train ChatGPT. When Musk discovered the agreement in December 2022, he reportedly deemed the price too low and cut access. Musk also admitted during legal proceedings that he used data from other labs’ AI models to train Grok, a practice called distillation that violates OpenAI’s terms of service.
Cursor co-founder Michael Truell pushed back quickly, noting that OpenAI models account for only about five percent of Cursor’s AI traffic. He said the company is in talks with OpenAI’s team and expressed frustration: “We’ve trusted their platform to be neutral infrastructure for our business.” Users who access GPT models through Cursor can still use their own OpenAI API keys, and OpenAI will continue offering access via its IDE extensions.
The move carries a familiar irony. OpenAI has been on the receiving end of similar cutoffs — Anthropic blocked Windsurf from Claude models in June 2025, then revoked OpenAI’s own API access in August 2025 after discovering internal use of Claude for GPT-5 benchmarks. What’s new here is the explicit framing around safety. OpenAI cites the upcoming Astra model’s reported cyber capabilities as demanding “a new level of accountability” from partners. That’s a curious justification from a company that spent years warning about AI risk while apparently tolerating looser standards until a rival acquired one of its customers. The timing makes the safety argument feel more like leverage than principle.
