Anthropic releases Claude Opus 5.5 with tighter security

How it developed

1. September 22, 2026The Verge AIWhere it started

   Anthropic releases Claude Opus 5.5 with tighter security

2. September 22, 2026TechCrunch AI

   Anthropic releases Opus 5.5 with lower prices

   Opus 5.5 lowers output costs to $20 per million tokens while maintaining performance that beats the larger Fable model in coding and knowled

3. September 22, 2026GitHub Changelog

   Claude Opus 5.5 arrives in GitHub Copilot

   Claude Opus 5.5 is now available in GitHub Copilot for enterprise developers.

4. September 23, 2026Matthew Berman

   Anthropic releases Opus 5.5

5. September 23, 2026Duncan Rogoff

   Anthropic releases official Claude Code playbook for Opus 5.5

   Anthropic released an official guide optimizing Claude Code with Opus 5.5 to reduce latency and cost through specific prompting habits.

6. September 24, 2026AI Explained

   Anthropic Releases Claude Opus 5.5 Model

7. September 25, 2026Lev Selector

   Claude Opus 5.5 and GPT-6 Sol Released

   OpenAI launches GPT-6 Sol and Luna variants alongside Anthropic's release.

8. September 26, 2026Matt Wolfe

   Anthropic Releases Claude Opus 5.5

9. September 30, 2026Matt Wolfe

   Anthropic Releases Opus 5.5 Coding Model