Open access: Half the time Unpaywall users search for academic journal articles that are legally free to access — Quartz

"Now a new study has found that nearly half of all academic articles that users want to read are already freely available. These studies may or may not have been published in an open-access journal, but there is a legally free version available for a reader to download.

To arrive at this conclusion, researcher Heather Piwowar and her colleagues used data from a web-browser extension they had developed called Unpaywall. When users of the extension land on an academic article, it trawls the web to find if there are free versions to download from places such as pre-print services or those uploaded on university websites.

In an analysis of 100,000 papers queried by Unpaywall, Piwowar and her colleagues found that as many as 47% searched for studies that had a free-to-read version available. The study is yet to be peer-reviewed, but Ludo Waltman of Leiden University told Nature that it is 'careful and extensive.'"