While nowadays there is a lot of content being published open access, 45% more than in 2015 (Alperin 2017), there is still a lot of scientific literature subscription based, behind the paywall. This year, the gap between content discovery and its access shrunk substantially. Due to initiatives from organizations or publishers, different solutions were launched for finding and accessing full-text articles wherever they can be backtracked via their DOI. New tools to browse preprint articles appeared, publishers are changing their publishing model to gold OA, money is invested in infrastructures of preprints and, in the absence of an OA versions online, active requests are sent to authors to ask them to put their article version in repositories. (Piwowar and Priem 2017)
Launched in the beginning of the year, Unpaywall tool reached a large audience fast. It’s a browser extension (free for Chrome and Firefox) from Impact Story, the founders of oaDOI – see previous article about it. The extension looks for a free version of articles behind the paywalls by searching into a vast number – 5300 – repositories world-wide (DOAJ, BASE, PubMed Central, CrossRef, DataCite, Google Scholar) and goes beyond oaDOI by looking directly in the page of articles themselves, parsing them to find a link to a pdf (Chawla 2017). It is the legal approach that differentiate it from SciHub.
It is a simple elegant solution, effective in more than 50% of search cases (Piwowar and Priem 2017): on the webpage of an article, a lock appears in the right of the page (fig. 1). The colour code is gold and green for Gold OA and Green OA, blue for lack of information because of browsing behind the paywall and grey color when no information is found.
Unpaywall is doing almost the same as the Open Access Button (OA Button). This is as well a free tool, developed in 2013, which extends its search functionality to requesting an article or data directly from the author when no free version is found online (fig. 2).
Moreover, in July 2017, JISC announced a project “assessing the feasibility of a service in the discovery/interlibrary loan (ILL) workflow utilising Open Access Button functionality to aid the discovery, creation and promotion of open access content” (Fahmy 2017). On their blog, OA Button reports that Indiana University-Purdue University Indianapolis successfully implemented the service and reported six-numbered savings (OpenAccessButton 2017).
On the practical side, trying out Unpaywall and OA Button for the same article gets us different results – as expected – because of their use of different full-text databases (Open Access Button/about 2013).