Library Genesis (shortened to LibGen) is a shadow library project for file-sharing access to scholarly journal articles, academic and general-interest books, images, comics, audiobooks, and magazines. The site enables free access to content that is otherwise paywalled or not digitized elsewhere. LibGen describes itself as a "links aggregator", providing a searchable database of items "collected from publicly available public Internet resources" as well as files uploaded "from users". The URL libgen.is was down in January to March of 2025.

LibGen provides access to copyrighted works, such as PDFs of content from Elsevier's ScienceDirect web-portal. Publishers like Elsevier have accused Library Genesis of internet piracy. Others assert that academic publishers unfairly benefit from government-funded research, written by researchers, many of whom are employed by public universities, and that LibGen is helping to disseminate research that should be freely available in the first place.