OpenAI terminates Cursor contract after SpaceX buyout

OpenAI has announced it will terminate its contract with the AI coding assistant Cursor on November 12, 2026. This decision was triggered by SpaceX's acquisition of Cursor, which activated a change-of-ownership clause in the agreement. OpenAI representative Thibault Sottiaux explained the move by stating that "it boils down to trust," pointing to a pattern of contract breaches by Elon Musk's companies. Specifically, OpenAI recalled how Musk terminated a $2 million annual Twitter data licensing agreement for ChatGPT training in December 2022 and admitted to using other labs' data to train his Grok models.

For software developers using Cursor, the immediate disruption may be minimal. Users can still access GPT models by inputting their personal OpenAI API keys, and OpenAI will maintain its own IDE extensions for the platform. Furthermore, Cursor co-founder Michael Truell revealed that OpenAI models currently represent only about five percent of the tool's total AI traffic. The platform is already in discussions with OpenAI to resolve the issue, though it has historically relied on the startup as a neutral infrastructure provider.

OpenAI also framed the decision around safety, pointing to its upcoming Astra model. Because Astra features advanced cyber capabilities, the company argues that strict adherence to terms of service is more critical than ever. Meanwhile, rival Anthropic is capitalizing on the dispute. Tom Brown, Anthropic's co-founder and Chief Compute Officer, announced that the company will expand compute capacity for its Claude models, such as Sonnet 3.5, within Cursor to establish itself as a more stable partner.

This corporate sparring highlights a broader trend of API access being weaponized in the AI sector. In June 2025, Anthropic blocked the coding tool Windsurf after reports of a planned acquisition by OpenAI. Later, in August 2025, Anthropic revoked OpenAI's own API access after discovering that OpenAI teams were using Claude to run internal benchmarks ahead of the GPT-5 launch.