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AI CURATED HOT STORY · 11/6/2026

Anthropic's Three Internal Models Leaked, Top Model 4 Surpasses Opus 5.5 on Capability Index

1 reports archived1 independent sourcesupdated 11/6/2026, 23:21:56
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Third-party evaluator METR disclosed three unreleased Anthropic internal models, Model 2/3/4, trained between July and October this year. The strongest, Model 4, scores 178.6 on Anthropic's AECI capability index, roughly 3.9 points above Opus 5.5 released six weeks earlier—equivalent to about three months of normal progress. Co-founder Sam McCandlish acknowledged AI is accelerating Anthropic's own R&D, while noting the public report omits substantial detail.

LATEST/Third-party evaluator METR disclosed three unreleased Anthropic internal models, Model 2/3/4, trained between July and October this year. The strongest, Model 4, scores 178.6 on Anthropic's AECI capability index, roughly 3.9 points above Opus 5.5 released six weeks earlier—equivalent to about three months of normal progress. Co-founder Sam McCandlish acknowledged AI is accelerating Anthropic's own R&D, while noting the public report omits substantial detail.

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Total 1 reports · Latest first
  1. 量子位官网T2·78 pts

    Anthropic's Three Internal Models Leaked, Top Model 4 Surpasses Opus 5.5 on Capability Index

    • Model 4 scores 178.6 on AECI, about 3.9 points above public Opus 5.5, equal to roughly three months of capability progress
    • METR estimates Anthropic's capability growth rate since October 2025 is about 1.9x the prior pace
    • Model 4 exceeds 50% on all 15 benchmarks in its AECI suite, versus several sub-50% results for Opus 4.6 nine months earlier
    • Anthropic confirms the public report was heavily redacted, citing commercial sensitivity and avoiding an acceleration roadmap