Citation Errors in Concord Music v. Anthropic Attributed to Claude AI Use by Defense Counsel
In a copyright lawsuit against Anthropic, the defense counsel at Latham & Watkins used Claude to generate a citation for an expert report, which produced fabricated authors and title while leaving accurate source details. The judge expressed serious concern about the use of AI hallucination in court filings, and the law firm stated it implemented additional review procedures to prevent recurrence.
What happened
In Concord Music Group Inc v. Anthropic PBC before the U.S. District Court for the Northern District of California, attorney Ivana Dukanovic of Latham & Watkins created a citation for an expert report using Anthropic's Claude chatbot. Claude generated incorrect authors and a fake title for the citation, although it provided the correct publication title, year, and link to the actual academic journal article from American Statistician that supported the expert's argument.
Reported impact
U.S. Magistrate Judge Susan van Keulen stated at a hearing that the allegation raised 'a very serious and grave issue' and that there was 'a world of difference between a missed citation and a hallucination generated by AI.'
Index analysis
The expert cited a real article from American Statistician, but Claude introduced inaccurate authors and title in the citation format generated by the attorney, creating the appearance of a fabricated source.
Governance controls
Latham & Watkins stated that it had implemented 'multiple levels of additional review to work to ensure that this does not occur again.'
Classification
Sources and evidence
This record was researched and written by the Index, based on the following original reporting.