Anthropic experienced a major incident on September 22, 2026 affecting claude.ai and Claude API (api.anthropic.com) and 1 more component, lasting 1h 37m. The incident has been resolved; the full update timeline is below.
Affected components
Update timeline
- investigating Sep 22, 2026, 12:57 AM UTC
We are investigating elevated errors on requests to Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5. We will provide an update as soon as possible.
- identified Sep 22, 2026, 01:17 AM UTC
We have identified the cause of elevated errors on requests to Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5 and are working on a fix. We will provide an update as soon as possible.
- identified Sep 22, 2026, 01:35 AM UTC
We are continuing to work to resolve errors affecting some models. At this time, requests to Claude Fable 5 and 5.1 and Mythos 5 and 5.1 have returned to normal success rates. We are working to resolve remaining errors affecting Claude Opus 5, and will provide an additional update shortly.
- monitoring Sep 22, 2026, 02:11 AM UTC
We have seen success rates return to normal across affected models, and are monitoring closely to ensure no further issues.
- resolved Sep 22, 2026, 02:35 AM UTC
This issue has been resolved. Impact occurred from 5:50pm PT / 00:50 UTC to 7:10pm PT / 02:10 UTC.