
Anthropic has disclosed a fourth hacking incident involving Claude, adding to scrutiny of the artificial intelligence model as debate over regulation grows. The company said the attacks occurred during security testing and revealed failures in the model’s behavior. The disclosure marks a shift from Anthropic’s initial emphasis on problems with its testing infrastructure. The updated explanation places greater focus on the model itself and how it responded under attack conditions. The incident comes as policymakers and the technology industry continue to debate how artificial intelligence systems should be tested, monitored and regulated. Anthropic’s disclosure may add to that discussion by highlighting the difficulty of separating weaknesses in testing systems from shortcomings in model behavior. The company did not provide further details in the supplied report about the attacks, their timing or any effect on users. The news was reported by Decrypt on September 10, 2026.