Claude's new system prompt doesn't want to reproduce song lyrics

Anthropic has updated Claude's system prompt to explicitly prohibit reproducing song lyrics, poems, and passages from copyrighted books, likely in response to recent lawsuits from Sony Music Publishing and Warner Chappell over training data. The update also extends restrictions to copyrighted visual works and characters, while allowing reproduction of works published before 1929. Anthropic publicly shares its system prompts and historical changes, making these policy updates transparent and easily comparable.