Anthropic said on August 7 local time that it has updated the biosecurity safeguards in Claude Fable 5, reducing false blocks by improving its classifier. Jiemian News reported that the update cut bio-related fallback switches across the product's platforms by about 85%, allowing users to handle more biology-related tasks with Fable 5.

The company said the change should reduce false blocks in everyday health consultations, lab result interpretation and biology education, while giving medical professionals more support for clinical tasks. For virology, toxicology and molecular design requests that carry dual-use risk, however, Fable 5 will still switch to a lower-capability model for processing.