Elon Musk asked a judge to block OpenAI's attempt to transition from nonprofit to for-profit. It's not the first time he's feuded with CEO Sam Altman.

"I genuinely respect your accomplishments and think you are the most inspiring entrepreneur of our time," Altman wrote in an X post to Musk.

Elon Musk and OpenAI CEO Sam Altman are fighting on X about Stargate, the infrastructure project to build data centers for OpenAI in the U.S.

Altman and Musk were OpenAI’s founding co-chairs in 2015, but their relationship has devolved into name-calling and lawsuits.

The latest spat began after Altman joined Trump, SoftBank CEO Masayoshi Son, and Oracle Chairman Larry Ellison in a White House ceremony on Tuesday to announce the launch of Stargate, a $500 billion venture to advance the United States’ artificial intelligence infrastructure.

Altman said that a project like Stargate might not have been possible with "a different president."

Elon Musk is clashing with OpenAI CEO Sam Altman over the Stargate artificial intelligence infrastructure project touted by President Donald Trump, the latest in a feud between the two billionaires that started on OpenAI’s board and is now testing

OpenAI, Oracle, SoftBank, and MGX are the lead partners in Stargate, according to OpenAI.

OpenAI CEO Sam Altman announced on Thursday that the new o3-mini reasoning model will power ChatGPT chat sessions for free tier users.

President Donald Trump spoke with OpenAI CEO Sam Altman by phone Friday, ahead of the AI infrastructure announcement, CNBC has learned.

The Stargate project has big implications for U.S. AI leadership, but also for who's winning the new president's ear.