Elon Musk announced that xAI has open-sourced the weights for Grok 2.5, once its most advanced model, making them publicly available on Hugging Face, the popular AI developer platform 

In his post on X (formerly Twitter), Musk wrote: “The @xAI Grok 2.5 model, which was our best model last year, is now open source.” He further revealed that Grok 3 will be made open source in about six months.

What’s in the release?

Reports indicate that the open-sourced Grok 2.5 model consists of approximately 42 files totaling around 500 GB. Running it in-house requires significant compute resources—at least eight GPUs, each with more than 40 GB of VRAM .

A License with Caveats

Despite the label “open source,” AI engineer Tim Kellogg has raised concerns over the licensing terms. He described the Grok license as “custom with some anti-competitive terms,” implying that there may be restrictions on commercial use or redistribution .

Community Reactions

Public discourse, including on platforms like Hacker News, reveals skepticism about the release’s openness:

“Open weights… they do allow commercial use but with stipulations to do no harm, follow the law and not circumvent the guardrails.”

“Smoke and mirrors… hostile license, old model and it’s open weight and not open source.”

Why This Matters

This move from xAI marks a continuation of Elon Musk’s promise to progressively open-source his company’s AI models, a strategy first established with the Apache-2.0 release of Grok-1 in March 2024 .

By allowing external developers to access model weights, xAI hopes to foster innovation, transparency, and collaboration—though the restrictive license may limit these goals in practice.

At a Glance