AI companies are buying and destroying millions of printed books to secure clean training data

AI Companies Turn to Printed Books for Uncontaminated Training Data

A market originally built for libraries and booksellers is now feeding the appetite of AI companies desperate for clean training data. ISBNdb, which maintains what it claims is the world's largest book database, has pivoted to help AI firms source physical books in bulk—coordinating purchases ranging from 1,000 to 1 million books at a time 1

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. The company's pitch is straightforward: "The world's best AI training data is sitting on a shelf," emphasizing that printed books represent "curated, peer-reviewed, domain-specific human knowledge, structured in a way no web crawl can replicate" 3

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The focus centers overwhelmingly on books published before 2022, before AI-generated text contamination became widespread online. This temporal boundary matters because AI models trained on synthetic content can suffer from model collapse—a documented degradation where each generation performs worse than the last 2

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. ISBNdb frames print as a solution to this risk, stating that "print books from the pre-LLM era are structurally guaranteed to be free of this contamination" and are "structurally clean of modern poisoning tools" [1](https://www.techspot.com/news/113277-ai-firms-qui etly-buying-destroying-millions-printed-books.html).

The Destructive Scanning Process Reshaping the Used-Book Market

To make these books usable at scale for large language models, AI companies employ destructive scanning—a process where the spine is cut and pages are fed through high-speed machines. This method is faster and cheaper than scanning intact books, but it permanently destroys the originals 1

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. Internal documents from Anthropic's Project Panama described plans to buy and scan millions of books, with many destroyed during the process 4

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. According to the settled lawsuit, Anthropic used "a hydraulic powered cutting machine to neatly remove the pages from the books it procured from book resellers and then scanned them using industrial-grade imaging equipment" 4

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The surge in bulk-purchasing books has dramatically altered the used-book market. One bookseller specializing in foreign-language titles reported that sales changed dramatically starting in April, jumping from roughly 20 books per week to several hundred 4

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. "I personally have mixed feelings about all of this," the seller told 404 Media. "It benefits me financially as well as by clearing out old inventory that is otherwise unlikely to sell. On the other hand, I don't like the end-use, and I don't like that uncommon books are being pulped" 1

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Data Acquisition Strategies and the Confidentiality Problem

ISBNdb emphasizes strict confidentiality in its data acquisition strategies, stating that every engagement is covered by a nondisclosure agreement and that "the buyer's identity, strategy, and acquisition targets are kept confidential" 1

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. This secrecy reflects what the company itself acknowledges as an optics problem. "'AI company destroys two million books' is not a headline that generates sympathy," ISBNdb's website plainly states 1

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Sellers on platforms like Alibris and Biblio report seeing sharp increases in bulk orders in recent months, though buyers remain unidentified. On an Alibris forum, one user asked about an uptick in AutoBuy orders since late last year. Mike Feldman, director of client services at Alibris, confirmed: "We have a couple of new bulk buyers that are scooping up trade books so lots of sellers are getting lots of orders" 1

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. The orders stand out not just for their size but because they appear scattered across topics and formats, ignoring normal pricing patterns.

Legal Controversies and the Fair Use Ruling

The practice has sparked significant copyright litigation. Federal Judge William Alsup ruled that Anthropic's destructive scanning process qualified as fair use under the first-sale doctrine. "Here, every purchased print copy was copied in order to save storage space and to enable searchability as a digital copy," Judge Alsup wrote. "The print original was destroyed. One replaced the other. And, there is no evidence that the new, digital copy was shown, shared, or sold outside the company." He called the use "clearly transformative" 1

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However, in a separate case, a federal judge approved a $1.5 billion settlement requiring Anthropic to pay thousands of authors approximately $3,000 per book after the company used pirated copies to train Claude 5

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. ISBNdb points to the fair use reasoning in its own materials, arguing that bulk-purchasing books from the secondary market doesn't deprive creators of income because the books have already been sold once 1

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Data Poisoning and the Race for Data Quality

Beyond avoiding AI-generated text contamination, AI companies face another threat: data poisoning. Authors have started fighting back using tools like Nightshade, which lace text with characters that humans read normally but models cannot process correctly 2

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. ISBNdb's blog cites Anthropic research suggesting that as few as 250 to 500 crafted documents can plant a backdoor in a corpus of trillions of tokens 2

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. Pre-2022 printed books, written before any of these tools existed, sidestep this problem entirely, offering what ISBNdb markets as provenance: buy the paper, keep the receipts, and legal teams hold a clean chain of custody.

Ethical Concerns and Industry Response

The practice has raised ethical concerns across the industry, particularly regarding out-of-print books and rare titles. Booksellers report that their inventory includes rare and out-of-print books, meaning AI companies could be destroying some of the few remaining copies 4

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. Rare booksellers in the Netherlands are reportedly being inundated with bulk purchases believed to be from AI companies 4

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Elon Musk has spoken out against the practice, stating: "I've asked the SpaceXAI team to preserve any rare books in a library and scan them the hard way vs just cutting off the spine and scanning" 5

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. ISBNdb attempts to reframe the practice, stating: "Responsible physical sourcing is not book burning. It is the completion of a book's lifecycle: from tree to knowledge to tree again" 1

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. Ingram, the largest book distributor in the US, has already warned publishers and offered them a way to opt out 2

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