The website Sci-Hub enables users to download PDF versions of scholarly articles, including many articles that are paywalled at their journal’s site. Sci-Hub has grown rapidly since its creation in 2011, but the extent of its coverage has been unclear. Here we report that, as of March 2017, Sci-Hub’s database contains 68.9% of the 81.6 million scholarly articles registered with Crossref and 85.1% of articles published in toll access journals. We find that coverage varies by discipline and publisher, and that Sci-Hub preferentially covers popular, paywalled content. For toll access articles, we find that Sci-Hub provides greater coverage than the University of Pennsylvania, a major research university in the United States. Green open access to toll access articles via licit services, on the other hand, remains quite limited. Our interactive browser at https://greenelab.github.io/scihub allows users to explore these findings in more detail. For the first time, nearly all scholarly literature is available gratis to anyone with an Internet connection, suggesting the toll access business model may become unsustainable.
Piracy very often is the social pressure that drives innovation and positive change. Look at the rise of the video streaming industry. That wouldn’t have happened if not for people otherwise opting for the more convenient option of pirating.
Its unfortunate, but as things currently stand, Sci-Hub isn’t just some niche project, but is essential for science. The reason we have publishers scrambling to fight is that they on the other hand, are not essential to the scientific process. In this day and age, they bring no value to the table, and they’ve realised this.