Glossary
Shadow library
An online collection that distributes copyrighted books or papers without permission from rights holders.
A shadow library is a website or file collection that offers large numbers of books or academic papers for free download without authorization. Library Genesis and Z-Library are frequently cited examples.
Shadow libraries feature in AI copyright cases because some developers are alleged to have downloaded books from them to build training data. Courts have treated the act of obtaining pirated copies as a separate question from whether training itself is fair use.
Downloading through file-sharing networks can also mean uploading to others at the same time, which can raise distinct claims about distribution.
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