OpenAI said it made the decision because it could not be confident SpaceX would use its technology within its terms of service, citing what it described as a history of contract violations by Musk’s companies.

“We are making this choice because 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.

Musk responded early Saturday in an X post, writing, “I couldn’t care less.”

He accused Altman and OpenAI President Greg Brockman of being “untrustworthy,” while repeating his assertion that they “stole an open source nonprofit.”

The latest dispute adds to a yearslong feud between Musk and Altman that culminated earlier this year in a trial over Musk’s $150 billion lawsuit against OpenAI.

During the trial, Musk’s lawyer said Musk and other witnesses had testified that Altman was a liar, while OpenAI argued that Musk had sought control of the company.

Musk, the world’s richest person, had sued OpenAI and Altman for “stealing a charity” by betraying the company’s original nonprofit mission for their own enrichment.

A federal jury ruled against Musk earlier this year, finding that he had filed the case too late.

Meanwhile, Michael Truell, a co-founder of Cursor and now an executive at SpaceX, said on X that the company was speaking with the OpenAI team to resolve the issue.

Hours after OpenAI’s announcement, Anthropic, which competes with both companies but has an ongoing partnership with SpaceX, said it planned to increase computing capacity to support Claude models in Cursor, according to Tom Brown, one of the firm’s co-founders.

OpenAI also said X, formerly known as Twitter and now part of SpaceX, had breached the terms of its contract with OpenAI after Musk acquired the platform.

“To work with a large partner like SpaceX, we typically rely on custom contracts to ensure compliance with our terms of service and that the integration provides for safety at scale,” the AI company added.

The ChatGPT maker said it had proposed Nov. 12, 2026, as the shutoff date, adding that its agreement with Cursor provided a limited window to cancel the contract following “a change of control.”

SpaceX announced a $60 billion all-stock deal to acquire Anysphere, the startup behind Cursor, in June and completed the acquisition earlier this month.