# Why Are AI Companies Buying Second-Hand Books? The legal implications and impacts of using books to train large language models - **Source:** [Fast Company](https://www.fastcompany.com) - **Published:** 2026-09-03 - **Topic:** [Data & AI](https://brifing.si/c/data-ai) - **Original article:** - **On Brifing:** https://brifing.si/s/f4036afe-afae-44ec-8483-455f7f26301e ## Using Books for AI Training AI companies are purchasing second-hand books to train their large language models. These books aim to provide models with a broader and more diverse language spectrum. While copyright restrictions limit the use of new books, second-hand books offer a legal alternative. Earlier this year, courts ruled that buying physical books for AI training falls under 'fair use.' ## Copyright and Fair Use US courts have classified the purchase and use of second-hand books by AI companies as fair use. This decision helped resolve disputes between copyright holders and AI firms. The ruling also includes the physical destruction of books after purchase. This clarification has defined the legal status of data sources used in AI training. ## Impact on the Second-Hand Book Market The demand from AI companies has revitalized the second-hand book market. Rare and out-of-print books have seen increased value, affecting collectors as well. Booksellers and antiquarians are expanding their inventories to meet the growing demand from AI firms. This trend has created a new market segment within the book industry. ## Diversity in Training Data Diverse and extensive datasets are crucial for improving AI model performance. Second-hand books expose models to language usage from different eras and authors. This diversity enables models to generate more natural and human-like text. Additionally, the physical destruction of books offers advantages in terms of data security. ## Future Legal Regulations The court decision addressed legal gaps regarding data sources used in AI training. However, more comprehensive regulations are still needed. Debates focus on protecting copyright holders' rights and limiting AI companies' activities. International standards are expected to emerge in the future to govern this area. ## AI Companies' Strategies AI companies are developing various strategies to navigate copyright issues. Purchasing second-hand books is just one of these approaches. Some firms use open-source datasets, while others negotiate directly with authors. This variety helps make AI training processes more transparent and legally compliant. ## Preserving Cultural Heritage The use of second-hand books in AI training also plays a role in preserving cultural heritage. Digitizing books ensures rare works are passed on to future generations. However, the physical destruction of books has drawn criticism from some quarters. This raises questions about balancing cultural preservation with technological progress. ## AI and the Book Industry The influence of AI companies on the book industry is growing. This trend creates new opportunities and challenges for authors, publishers, and booksellers. The distribution of copyright revenues is a particularly contentious issue. Future collaborations and regulations between AI and the book industry are anticipated. ## Sources covering this story - https://www.fastcompany.com/91602158/why-are-ai-companies-buying-books — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._