Elon Musk says xAI has open sourced Grok 2.5

Elon Musk’s xAI has made an older version of its AI model Grok — specifically, the model weights used to shape Grok 2.5 —  available on the open source platform Hugging Face.

“The @xAI Grok 2.5 model, which was our best model last year, is now open source,” Musk wrote on X. He added that Grok 3 “will be made open source in about 6 months.”

AI engineer Tim Kellogg described the Grok license as “custom with some anti-competitive terms.”

Grok, which is prominently featured on X (which in turn recently merged with xAI), has created considerable controversy this year, particularly after the chatbot seemed to become obsessed with “white genocide” conspiracy theories, expressed skepticism about the Holocaust’s death toll, and described itself as “MechaHitler,” leading xAI to publish its system prompts on GitHub.

And while Musk described the latest version, Grok 4, as a “maximally truth-seeking AI,” the model appears to consult Musk’s social media account before answering controversial questions.