Anthropic Reduces False Positives in Claude Fable 5 Biology Safeguards

Anthropic updated Claude Fable 5's biology safeguards to significantly reduce false positives. The updates reduce biology-related fallbacks by approximately 85%, where the system switches to a less capable model after biology-related queries. Users should experience far fewer fallbacks on everyday health and educational questions. Healthcare professionals will receive more support from Fable 5 on clinical tasks. However, Fable 5 continues to fallback to Opus 5 for dual-use applications, including virology, toxicology and molecular design, pending trusted access pathways for advanced biology capabilities.