Anthropic RSI is here? METR reports ANT likely hits 2x RSP acceleration limit

METR reports that Anthropic has probably hit the 2x acceleration threshold under its Responsible Scaling Policy and may now be running as high as 3x, citing a new internal Anthropic model METR calls Model 4 that finished training last month and is the first model in METR's analyzed set to clear 50% on every benchmark it was tested on. METR estimates that a majority — perhaps about 80% — of the current acceleration as of October 2026 is due to AI, and the report ties the findings to Anthropic's earlier disclosure of a dramatic acceleration in AI R&D.

Andrew Curran on X: "Anthropic has a new internal model that finished training last month. METR refers to it as Model 4 Anthropic has its own internal codename . It is the highest-scoring model in the set METR analyzed, and it is the first to clear 50% on every benchmark it was tested on." / X Andrew Curran on X: "Anthropic has a new internal model that finished training last month. METR refers to it as Model 4 Anthropic has its own internal codename . It is the highest-scoring model in the set METR analyzed, and it is the first to clear 50% on every benchmark it was tested on." Anthropic has a new internal model that finished training last month. METR refers to it as Model 4 Anthropic has its own internal codename . It is the highest-scoring model in the set METR analyzed, and it is the first to clear 50% on every benchmark it was tested on. METR says Anthropic has probably hit the 2x Responsible Scaling Policy acceleration threshold, and may now be running as high as 3x 'We guess that a majority perhaps ≈80% of the current October 2026 acceleration is due to AI.' Anthropic has a new internal model that finished training last month. METR refers to it as Model 4 Anthropic has its own internal codename . It is the highest-scoring model in the set METR analyzed, and it is the first to clear 50% on every benchmark it was tested on. METR says Anthropic has probably hit the 2x Responsible Scaling Policy acceleration threshold, and may now be running as high as 3x 'We guess that a majority perhaps ≈80% of the current October 2026 acceleration is due to AI.' Quoting from the report: 'The plot below shows all benchmark scores for frontier models in the AECI, scaled on a log-odds scale, implying that they should evolve linearly with a model’s latent AECI score if the logistic assumption holds . The highlighted lines represent the 15Show more METR's report has a ton of details on Anthropic's internal models, including "Model 4", which finished training in September-October: - We now know where Anthropic got evidence on the "dramatic acceleration of AI R&D" disclosure. METR: "As of October 2026, Anthropic is likely