'After reviewing the internal evidence, we still have significant uncertainty and internal disagreements on the team, but most METR staff who worked on this project now believe that, as of October 2026, Anthropic is likely improving the capabilities of their models on well-specified tasks at around twice the rate they did between March 2024 and October 2025. We would not be surprised if the current rate of growth was closer to 1.3x or 3x the historical rate.'

'Beyond the AECI evidence, we also saw redacted evidence that significantly informed our view on this question, and made us take this apparent ≈2x acceleration more seriously. It also gave us some indication that acceleration could be above 2x and increasing over time, though we would be surprised if it was significantly higher.'