OpenAI announced Friday that it plans to terminate its contract with Cursor, the popular AI coding tool now owned by Elon Musk's SpaceX, effective November 12, 2026. The move marks a dramatic escalation in the years-long feud between OpenAI CEO Sam Altman and Musk.
"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," OpenAI said in a blog post. The company cited SpaceX's acquisition of Cursor — a $60 billion all-stock deal completed earlier this month — as triggering a change-of-control clause in their agreement.
Musk responded on X with his characteristic brevity: "I couldn't care less." He accused Altman and OpenAI President Greg Brockman of being "untrustworthy" and repeated his long-standing claim that they "stole an open source nonprofit."
The feud between the two men stretches back to OpenAI's founding in 2015, when Musk was an early backer. Their relationship deteriorated into a $150 billion lawsuit that went to trial earlier this year, with Musk's lawyers calling Altman a liar and OpenAI arguing that Musk had sought to control the company. A federal jury ruled against Musk, finding he had filed too late.
The immediate practical impact is significant. Cursor is one of the most widely used AI-powered coding tools, with millions of developers relying on it for code completion, debugging, and software generation. Losing access to OpenAI's models — including GPT-4 and its successors — would force Cursor to either switch providers or develop alternatives.
Anthropic moved quickly to capitalize on the situation. Hours after OpenAI's announcement, Anthropic co-founder Tom Brown said the company planned to increase compute support for Claude models within Cursor, positioning itself as a reliable alternative.
Cursor co-founder Michael Truell, now a SpaceX executive, said on X that the company was speaking with OpenAI to try to resolve the issue. However, the November 12 deadline and the depth of personal animosity between Altman and Musk make a resolution unlikely.
The episode highlights the growing concentration risk in the AI coding tool market, where a handful of model providers power the tools that millions of developers depend on. It also underscores how personal rivalries are increasingly shaping the competitive landscape of the AI industry.
