2025 December 10
It's Time: Planning for Metadata Schema Deprecation
It has been 18 (!) years since Crossref last deprecated a metadata schema. In that time, we’ve released numerous schema versions, some major updates, and some interim releases that never saw wide adoption. Now, with 27 different schemas to support, we believe it’s time to streamline and move forward.
Starting next year, we plan to begin the process of deprecating lightly-used schemas, with the understanding that this will be a multi-year effort involving careful planning and plenty of communication.





