It is possible to share a research article either with a persistent identifier (e.g. DOI, URN) or by uploading the publication to a separate social media networking service or repository. Many social media networking services have been created to promote researcher networking, such as ResearchGate, Academia.edu. These services attract researchers to share their research articles on their website and thus increase their visibility. When uploading your research article to the public view of a social media networking service, copyright issues, the chosen Creative Commons license, and how the publisher of the research article views these services must be taken into account. Some publishers do not allow uploading research articles on social media networking services, while others allow the sharing of a persistent identifier e.g. DOI. Social media networking services are not open access repositories, and they do not usually meet the funders criteria for open access publishing.
Publisher's policies for uploading articles to the public view of a social media networking service can be found in the Open policy finder service, on the publisher's website under article sharing policy, or in the How Can I Share it service.
Publishers who do not permit uploading research articles to social media networking services usually allow either depositing the preprint version of the research article in a preprint repository, or the self-archiving of the accepted manuscript in a repository. Self-archived articles receive a permanent identifier (e.g. URN) and sharing this identifier in various services is usually permitted. Publishers' self-archiving policies and practices can be found in the Open policy finder service or on the publisher's website under sharing policy, self-archiving.
The differences between repositories and social media networking services are discussed for example in an article by University of California’s Office of Scholarly Communication, A social networking site is not an open access repository.
