Anthropic blames Claude AI for ‘embarrassing’ legal filing error

Anthropic has responded to allegations that it used an AI-fabricated source in its legal battle against music publishers, saying its Claude chatbot made an “honest citation mistake.”

In a response filed on Thursday, Anthropic defense attorney Ivana Dukanovic said that the scrutinized source was genuine and that Claude had indeed been used to format legal citations in the document. While incorrect volume and page numbers generated by the chatbot were caught and corrected by a “manual citation check,” Anthropic admits that wording errors had gone undetected.

Dukanovic said, “unfortunately, although providing the correct publication title, publication year, and link to the provided source, the returned citation included an inaccurate title and incorrect authors,” and that the error wasn’t a “fabrication of authority.” The company apologized for the inaccuracy and confusion caused by the citation error, calling it “an embarrassing and unintentional mistake.”

This is one of many growing examples of how using AI tools for legal citations has caused issues in courtrooms. Last week, a California Judge chastised two law firms for failing to disclose that AI was used to create a supplemental brief rife with “bogus” materials that “didn’t exist.” A misinformation expert admitted in December that ChatGPT had hallucinated citations in a legal filing he’d submitted.