The OpenCitations Project has formally started in 2010 as a one-year project funded by JISC (with a subsequent extension), with David Shotton as director, who at that time was working in the Department of Zoology at the University of Oxford. The project was global in scope, and was designed to change the face of scientific publishing and scholarly communication, since it aimed to publish open bibliographic citation information in RDF and to make citation links as easy to traverse as Web links. The main deliverable of the project, among several outcomes, was the release of an open repository of scholarly citation data described using the SPAR (Semantic Publishing and Referencing) Ontologies, and named the OpenCitations Corpus (OCC), which was initially populated with the citations from journal articles within the Open Access Subset of PubMed Central.

In May 2014, OpenCitations was adopted by the Infrastructure Services for Open Access (IS4OA) as one of its academic Open Access services. IS4OA is UK-based not-for-profit charitable company that aims to provide benefit to the global community of research information users by acting as an umbrella organisation that supports openly accessible information and discovery services relating to academic information, research results and scholarly publications, by providing business structure and expertise and a means of channelling financial support to these services.

At the end of 2015 Silvio Peroni joined the OpenCitations Project as co-director and technical manager, with the aim of setting up a new instantiation of the Corpus based on a new metadata schema and employing several new technologies to automate the ingestion of fresh citation metadata from authoritative sources. The current instantiation of the OCC is hosted by the Department of Computer Science and Engineering (DISI) at the University of Bologna, and since the beginning of July 2016 has been ingesting, processing and publishing reference lists of scholarly papers available in Europe PubMed Central. Additional metadata for these citations are obtained from Crossref and (for authors) ORCID.