Judge hears Anthropic's fair-use defense in music publishers' lawsuit; no ruling yet

What happened

On October 21, 2026, US District Judge Eumi Lee heard arguments on competing summary-judgment motions in the music publishers' AI-training copyright lawsuit against Anthropic (sued in 2023 by Universal Music Group, Concord and ABKCO over the use of song lyrics to train Claude). No ruling was issued.

The competing positions

• Anthropic asked the court to rule that training Claude on copyrighted lyrics is transformative fair use: the material is used to develop an AI model capable of a wide range of tasks rather than to supply substitutes for the original works.
• The publishers argued Anthropic copied lyrics without permission and that Claude's ability to reproduce lyrics or generate competing material weighs against fair use. They pointed to evidence concerning nearly 120,000 prompts used to generate synthetic lyrics, arguing AI-generated material could compete with human songwriters' works.

The judge's focus

Judge Lee questioned both sides during the hearing, with particular attention on whether Anthropic's use could damage existing or potential markets for the copyrighted works — one of the factors courts consider in fair-use determinations.

Why it matters

The case is being watched as a bellwether: two other Northern California judges have split on whether generative AI training makes fair use of copyrighted material (one sided with Anthropic on books; another ruled for Meta but warned AI training would not be fair use in many circumstances). The fair-use determination could shape dozens of pending lawsuits by authors, news outlets, visual artists and others against AI companies.