Unpaywall reports three categories of paper version, based on the DRIVER Guidelines v2.0 VERSION standard (with our descriptions)

  • PublishedVersion: The document’s version of record which matches the version hosted at the publisher’s website. This is the most authoritative version.
  • AcceptedVersion: the document after having completed peer review and being officially accepted for publication. There may be minor content differences between the AcceptedVersion and the version of record such as differences in spelling, word choice, or sentence structure; however, the content should essentially interchangeable with the content of the PublishedVersion, for the information needs of a reasonable reader. The AcceptedVersion lacks most or all Publisher Formatting. The AcceptedVersion is the second-most authoritative version.
  • SubmittedVersion: the document as submitted to the publisher by the authors, but before peer-review. There may be significant differences in the content of the SubmittedVersion as compared to the final completed article. The SubmittedVersion is the third-most authoritative version.

If you run an IR, here are our recommendations for version reporting.