A coalition of music publishers has filed a second copyright infringement lawsuit against AI company Anthropic, and it’s a big one.

The companies, including Universal Music Publishing Group, Concord Music Group, and ABKCO Music, are seeking more than $3 billion in potential statutory damages over alleged infringement of more than 20,000 songs.

The complaint, filed today (January 28) in the Northern District of California, represents a dramatic escalation from the publishers’ first lawsuit against Anthropic, which was filed in October 2023 and covered around 500 works with potential damages of around $75 million.

In a statement provided to MBW, the plaintiffs said: “We have been compelled to file this second lawsuit against Anthropic because of its persistent and brazen infringement of our songwriters’ copyrighted compositions taken from notorious pirate sites.”

They added: “The new case also addresses Anthropic’s ongoing violation of these rights by exploiting lyrics in the training of new AI models without authorization, as well as in the outputs generated.

“In total, we are suing for infringement of more than 20,000 songs, with potential statutory damages of more than $3 billion. We believe this will be one of the largest (if not the single-largest) non-class action copyright cases filed in the U.S.”

The new complaint, obtained by MBW, makes two central allegations:

• That Anthropic’s founders illegally downloaded millions of pirated books via BitTorrent, including songbooks containing the publishers’ copyrighted musical compositions;
• And that Anthropic continues to infringe their works by training newer Claude AI models without authorization.

According to the complaint, the publishers only discovered the alleged torrenting activities in July 2025, when Judge William Alsup issued a ruling in a separate copyright case (Bartz v. Anthropic) that publicly revealed the company’s use of pirate library websites.

You can read the new filing in full here.

The filing claims that in June 2021, Benjamin Mann “personally used BitTorrent to download via torrenting from LibGen approximately five million copies of pirated books” for Anthropic’s use, and that Dario Amodei “personally discussed and authorized this illegal torrenting.”

The complaint alleges that Amodei himself had described LibGen as “sketchy,” and that Anthropic’s own Archive Team had deemed LibGen to constitute a “blatant violation of copyright” – yet the company proceeded with the torrenting regardless.

The publishers previously attempted to add these piracy claims to their original lawsuit, but Judge Eumi Lee denied that motion in October 2025. At the time, Anthropic argued that the proposed amendment was an improper attempt to “fundamentally transform this case at the eleventh hour.”

As a result, the publishers have now filed this separate action to pursue the torrenting claims.

The new lawsuit arrives just months after Judge Eumi Lee denied Anthropic’s motion to dismiss the publishers’ original case in October 2025.

In that ruling, the judge found that the publishers had adequately argued Anthropic had “actual knowledge of specific acts of infringement by Claude users with respect to Publishers’ lyrics.”

Anthropic has already agreed to pay $1.5 billion to a group of authors in a separate settlement over the use of pirated books to train its AI models.

Songs cited in the new complaint include Wild Horses, Sweet Caroline, Bennie and the Jets, Eye of the Tiger, Viva La Vida, and Radioactive.

This new lawsuit covers 714 works related to the alleged torrenting and 20,517 works related to ongoing AI training – a significant expansion from the 499 works at issue in the original case.

Anthropic’s valuation has also surged dramatically since the first lawsuit was filed. In October 2023, the company was valued at approximately $5 billion. According to today’s complaint, Anthropic is now valued at approximately $350 billion – a 70-fold increase.

Anthropic has not yet publicly responded to the allegations.

The lawsuit notes that UMPG has entered licensing agreements with AI companies including Udio and KLAY, but argues that AI development must proceed “in a manner that protects the rights of Publishers and songwriters.”