xAI Leases Colossus 1 to Anthropic

At the Code w/ Claude event held the previous day, Anthropic revealed a deal to use the entire capacity of SpaceX/xAI's Colossus data center. At first it seemed as though xAI was giving up its Grok model, but in fact Anthropic is leasing Colossus 1, while xAI continues to use the larger Colossus 2 for its own purposes.

The Colossus facility chosen for this deal has been the subject of significant environmental controversy. Its gas turbines initially operated without Clean Air Act permits or pollution-reduction equipment, classified as temporary, and reports have linked them to worsening air quality and increased hospital admissions. At a time when AI data centers themselves have become politically sensitive, this choice is unlikely to make a good impression.

Around the same time, xAI drew backlash from users after giving only two weeks' notice of the shutdown of several models, including Grok 4.1 Fast. Elon Musk said he personally reviewed the Anthropic team's safety work before allowing the Colossus 1 lease, and stated that compute resources could be reclaimed if an AI acts in ways that harm humanity.