Anthropic has stepped up its defence in a closely watched copyright fight with music publishers, arguing that training Claude on song lyrics is legally transformative and falls within US fair-use protections. The latest filing, reported by Billboard, came as the company recently secured another $5bn from Amazon, with the prospect of up to $20bn more on the horizon.

The dispute is part of a wider legal test over how far AI developers can rely on copyrighted material when building large language models. In June 2025, a federal judge in California found that Anthropic’s use of books to train Claude was “exceedingly transformative” and therefore fair use, although the court also said the use of pirated copies for a separate internal library was not excused. That ruling gave AI firms an important precedent, even as separate claims over music remain unresolved.

Music publisher BMG escalated the pressure in March 2026 with a federal lawsuit accusing Anthropic of using protected lyrics from artists including The Rolling Stones and Bruno Mars to train Claude without permission. According to the publishers, the company’s own records show the model was trained on lyrics so it could answer lyric-based prompts, while Anthropic says the system is a general-purpose tool whose uses are overwhelmingly unrelated to music.

Anthropic is also pushing back against claims that AI-generated songs are harming the market for human songwriters. The publishers have argued that such material is flooding streaming services and even appearing on the Billboard charts, but that framing sits uneasily with recent industry data. Deezer says 75,000 AI-generated tracks are uploaded each day, yet they still account for only 1% to 3% of streams, while Universal Music Group’s digital chief, Michael Nash, has said there is no evidence AI is materially diluting royalties for the company. For now, the case is likely to turn less on rhetoric about market saturation than on whether the court accepts Anthropic’s argument that its lyric training was transformative and non-infringing.

Source Reference Map

Inspired by headline at: [1]

Sources by paragraph:

Source: Noah Wire Services