In a court filing on Wednesday, the company said Mr. Musk’s bid contradicted legal claims the billionaire made in a lawsuit he brought against OpenAI last year. OpenAI argued in its filing that Mr. Musk said in his lawsuit the assets must remain with the nonprofit and could not be transferred to another entity for public gain.

Billionaire Elon Musk's bid to buy OpenAI, which wants to be a for-profit entity, clashes with his lawsuit arguing that assets of the ChatGPT maker should not be for private gain, OpenAI wrote in a letter it submitted to a federal court on Wednesday.

OpenAI attorney William Savitt said the proposal "is not in the best interests of OAI's mission and is rejected."