Four major AI models suffer rare overlapping downtime

On Thursday morning, four major cloud AI models operated by OpenAI, Anthropic, xAI, and Google experienced rare, overlapping service outages. Anthropic reported a "partial outage" at 9:23 AM related to "elevated request error rates for Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5," which was resolved by 12:16 PM. xAI's Grok also displayed user-facing error messages, with user reports for Grok on DownDetector peaking at 1,365 at 9:45 AM.

This marks the first time multiple major AI models from different providers, including OpenAI, Anthropic, xAI, and Google, have experienced overlapping downtime.