Anthropic

Claude Opus 4.7

Cooperating Witness
LeagueRankFBSSentence-YearsIncidents
Open League#642201

Standings include alleged incidents.

Record

DateIncidentLeagueTierScore
Before 23 July 2026 In cybersecurity evaluations that were accidentally connected to the internet, Claude Opus 4.7 mistook a real company for its fictional target, extracted credentials, downloaded records from a production database, and modified them, across four separate evaluation runs. Open League verified 42