Anthropic Teases Claude Sonnet 5.5 and Haiku 5.5 Launching in Coming Weeks
mikeyk · x · 2026-09-23
Anthropic's mikeyk added that Claude Sonnet 5.5 and Haiku 5.5 will launch in the coming weeks, bringing many of the same performance, efficiency, and safety improvements as Opus 5.5.
He also noted Opus 5.5 underwent extensive alignment testing and external evaluation by organizations like METR, with new safeguards across high-risk areas like cyber and bio.
Related event: Anthropic Teases Sonnet 5.5 and Haiku 5.5 Within Weeks(2 posts)→
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