Independent Assessment of AI R&D Acceleration at Anthropic in October 2026

Redaction summary: As part of this assessment, Anthropic had rights to redact any non-public information in this post. Per our approach to transparency, we had the right to disclose if Anthropic exercised redaction rights, and whether or not any of our findings depended significantly on redacted information. While we were able to freely share our highest-level conclusions about risk, Anthropic redacted a majority of the evidence we found most informative for these conclusions. Anthropic described the redactions as “aimed at removing confidential information that could accelerate other AI developers.”1 Some of these redactions are themselves challenging to describe clearly without revealing sensitive information we have been asked to redact. We share a table of important evidence we were and were not able to discuss given the redactions in our process section below. All redactions that were important for our conclusions are covered by our descriptions in that table or other in-line descriptions in the report below. Much of the redacted evidence we viewed had multiple plausible interpretations, and both METR and Anthropic researchers have significant uncertainty about how to synthesize the evidence into a holistic picture. This makes it hard for the public to judge this evidence themselves, reconcile it…