Fair use required the destruction

The court did not bless the practice. The destruction did. Under Bartz v. Anthropic, the training use is "spectacularly transformative" and the digital copy is a space-saving "format change" replacement. That inference — Bartz suggests — only holds if the original is gone. A licensor who returns the physical book leaves two copies on the shelf, and the format-change rationale collapses. The fair-use defense is therefore priced in irreplaceable pages: every book the lab keeps, it loses the safe harbor on; every book it pulps, it keeps.

ISBNdb's own marketing copy tells the brokers what that price buys. "The world's best AI training data is sitting on a shelf." The service exists to move that shelf quietly: one NDA, one bulk order, no name on the headline. ISBNdb's own answer to the obvious press line, "AI company destroys two million books," is to make sure no buyer is attached to it.

The mechanism travels. Any AI lab can license a deposit copy, scan on site, or partner with a library and return the original. None of those pipelines satisfy the format-change test. The defensive legal logic rewards the irreversible loss and prices the reversible supply chain out of the market. The court did not order the books destroyed. It built a rule that cannot tell the difference.