Sam Altman Doesn’t Trust Elon Musk’s Cursor, Musk Says He Couldn’t Care Less. Here’s Why He Is Right.

The long feud between Elon Musk and Sam Altman has moved from the courtroom to the products themselves. After SpaceX (SPCX) recently acquired Cursor parent company Anysphere for $60 billion, OpenAI decided to end its partnership with Cursor. The cutoff is set for Nov. 12.

OpenAI framed the decision around trust. The company said it could not be sure Musk's companies would stick to their terms, pointing to past contract disputes. Musk's reply on X was blunt. "I couldn't care less," he wrote, before again accusing Altman of stealing a nonprofit.

The bad blood goes back years. Musk helped co-found OpenAI as a nonprofit in 2015, then left the board in 2018. He launched rival xAI in 2023 and sued OpenAI, Altman, and Greg Brockman in 2024. Musk claimed that they had abandoned the original mission for profit, and sought $150 billion in damages. In May, a federal jury ruled against Musk on the grounds that he had filed too late. So, the question of whether OpenAI broke its founding promise was not even addressed. Musk has said he will appeal.

For SpaceX, losing OpenAI removes only a small slice from a platform that has plenty of other options. According to Cursor CEO Michael Truell, OpenAI's models make up only about 5% of Cursor's traffic.

Cursor's largest supplier, Anthropic, has signaled it wants to deepen the relationship after the SpaceX deal rather than step back. Moreover, Cursor now sits inside SpaceX alongside xAI's Grok and the company's huge computing power. The move arguably hurts the developers who like using OpenAI's models in Cursor more than it hurts Musk. Meanwhile, SpaceX has gained a fast-growing business worth around $4 billion in annual revenue.

At the end of the day, this is a small loss for SpaceX. On the business itself, Musk holds the stronger hand.

SpaceX operates and owns well-known services like Starlink, X.com, and SpaceXAI. The company is led by CEO Elon Musk, whose rivalry with OpenAI's Sam Altman is not a secret to anyone. Despite the Cursor setback, Musk is unlikely to be fazed, as has been evident from his track record running Tesla (TSLA), which has also had many detractors. SpaceX is headquartered in Starbase, Texas.