Anthropic Releases Claude Sonnet 5.5: Same Price, 30% Faster Workhorse
September 29, 2026 · Model Release Anthropic on Monday released Claude Sonnet 5.5, the second model in its Claude 5.5 family and a mid-tier workhorse…
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Anthropic Launches Claude Opus 5.5 at About 40% Lower Cost
Anthropic released Claude Opus 5.5 on September 22, saying the model matches Claude Fable 5.1 on most tasks while costing about 40% less to run…
Anthropic Says Claude Now Leads 26% of Its Own R&D
Anthropic published an R&D Automation Index showing that Claude now “leads” 26 percent of the work used to build its successor models, up from under…
Anthropic Merges Claude Chat and Cowork, Adds Docs and Slides
Anthropic announced that Claude chat and Cowork are merging into a single interface. Artifacts, Cowork, and Claude Design capabilities are now reachable from any conversation,…
Claude Formalizes Fermat’s Last Theorem; Fable 5.1 Ships
Anthropic said a Claude system working largely autonomously for 11 days on the Prove2Me platform produced the first end-to-end, computer-checked proof of Fermat’s Last Theorem…
Claude Formalizes Fermat’s Last Theorem; Fable 5.1 Ships
Anthropic said a Claude system working largely autonomously for 11 days on the Prove2Me platform produced the first end-to-end, computer-checked proof of Fermat’s Last Theorem…
Claude Formalizes Fermat’s Last Theorem; Fable 5.1 Ships
September 5, 2026 · Research · Anthropic Anthropic said a Claude system working largely autonomously for 11 days on the Prove2Me platform produced the first…