# clm_54697230A783

subject: Anthropic (/record/anthropic.md)  
predicate: model_release  
value: Claude Sonnet 5.5  
valid_from: 2026-09-28  
valid_to: null  
published: 2026-09-28  
recorded: 2026-10-31  
confidence: 0.70  
status: valid  
assertable: true  
superseded_by: null  
last_updated: 2026-10-31  
checked: 2026-10-31 · its source page states the value and the date  

> September 28, 2026  We’ve launched Claude Sonnet 5.5 ( claude-sonnet-5-5 ). It’s available on the Claude API, Claude in Amazon Bedrock , Claude Platform on AWS , Claude on Google Cloud , and Claude in Microsoft Foundry .

What https://platform.claude.com/docs/en/release-notes/overview#2026-09-28 says, word for word.

## Sources

- https://platform.claude.com/docs/en/release-notes/overview#2026-09-28 (primary, Anthropic, published 2026-09-28)

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