Open Data is the data that can be freely accessed, reused, remixed and redistributed, for academic research and teaching purposes and beyond. Ideally, open data have no restrictions on reuse or redistribution, and are appropriately licensed as such. In exceptional cases, e.g. to protect the identity of human subjects, special or limited restrictions of access are set.


Open Data are based on FAIR data principles:

  • Findable. It must be easy to find the data and the metadata for both humans and computers. This is enabled by machine-readable persistent identifiers (PIDs) and metadata.
  • Accessible: The (meta)data must be retrievable identifier using a standardized and open communications protocol, possibly including authentication and authorization.
  • Interoperable: The data can be combined and used with other data or tools. Data format must be open and interpretable, both at the data and metadata level.
  • Re-usable: Metadata and data should be well-described so that they can be replicated and/or combined in different settings. Also, the reuse of the (meta)data should be stated with (a) clear and accessible license(s).

Within the Open Data, sensitive personal data must be protected. General Data Protection Regulation (GDPR, European Union, 2016a) defines personal data as any information relating to an identified or identifiable natural person known as ‘a data subject’. According to GDPR, the ‘Special categories of personal data’ are:

  • Racial or ethnic origin;
  • Political opinions;
  • Religious or philosophical beliefs;
  • Trade union membership;
  • Genetic data;
  • Biometric data;
  • Data concerning health;
  • Data concerning a natural person's sex life or sexual orientation.

Research data can be made accessible by publishing as supplemental material with a research article, hosting on a publicly-available website, depositing in a repository developed to support data publication (e.g., Dataverse, Dryad, Figshare, Zenodo) or by publishing a data paper about the dataset. Data citation services help research communities discover, identify, and cite research data.