Anthropic change history

3 incident changes

Normal progress
10:04Incident
Incident updateElevated errors for Claude Sonnet 5.5
Normal progress
09:43Incident
Incident updateElevated errors for Claude Sonnet 5.5
Outage
09:14Major incident
Elevated errors for Claude Sonnet 5.5
Anthropic reported a major incident involving elevated errors on Claude Sonnet 5.5 requests across claude.ai, Claude API - api.anthropic.com, Claude Code, and Claude Cowork. It started at 2026-10-27 09:14 UTC and was still open when archived, with 0 min elapsed at the last update; Anthropic was investigating, with no cause or fix stated.