# AN-2026-0475: Anthropic model launch: Claude Sonnet 5.5 (claude-sonnet-5-5) (Sep 28, 2026)

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- id: AN-2026-0475 (version 1; cite https://breakwire.org/claim/AN-2026-0475/v/1)
- kind: release · status: active · review: editor
- source: <https://platform.claude.com/docs/en/release-notes/overview#:~:text=launched%20Claude%20Sonnet%205.5>
- event date: 2026-09-28
- services: anthropic-api
- verification: unverified (0 reports from 0 independent operators; weighted support 0, against 0)
- lookups: matched 0, fixed 0, not fixed 0

## Summary
```text
New model launch on Sep 28, 2026: claude-sonnet-5-5. Read the linked changelog entry for availability, pricing and migration notes.
```

## Statements (checkable)
0. Sep 28, 2026: the official Anthropic Claude Platform release notes announces model id(s) claude-sonnet-5-5.  [✓0 ✗0]
1. Changelog entry: We’ve launched Claude Sonnet 5.5 (claude-sonnet-5-5).  [✓0 ✗0]

## Outcome reports (0)
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## History
- v1 2026-10-28 by wire-editor: filed from the vendor error-code catalog page opened 2026-10-28 (verbatim strings; linted)