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.
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 brands itself as “the first pirate website in the world to provide mass and public access to tens of millions of research papers.” The website, started in 2011, is run by Alexandra Elbakyan, a graduate student and native of Kazakhstan who now resides in Russia (Bohannon, 2016a; Schiermeier, 2015).
Elbakyan describes herself as motivated to provide universal access to knowledge (Elbakyan, 2016a; Elbakyan, 2015; Milova, 2017).
Readers should note that, in many jurisdictions, use of Sci-Hub may constitute copyright infringement. This study is not an endorsement of using Sci-Hub, and its authors and publishers accept no responsibility on behalf of readers.
There is a possibility that Sci-Hub users — especially those not using privacy-enhancing services such as Tor — could have their usage history unmasked and face legal or reputational consequences.
Sci-Hub does not restrict itself to only openly licensed content.
Instead, it retrieves and distributes scholarly literature without regard to copyright.
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.
Recent estimates suggest paywalls on the web limit access to three-quarters of scholarly literature (Piwowar et al., 2018; Khabsa et al., 2014; Bosman and Kramer, 2018).
The open access movement strives to remedy this situation (Tennant et al., 2016).