The DataCite Metadata Working Group. (2024) just released the new version of the DataCite Metadata and one of the things that it includes is RRIDs.
DataCite Metadata Schema Documentation for the Publication and Citation of Research Data and Other Research Outputs. Version 4.6. DataCite e.V. https://doi.org/10.14454/mzv1-5b55
Why should someone include an RRID in their DataCite record?
Even though data is fast becoming a first class citizen in research, academic databases are not yet on par with journals when it comes to data citations. The RRID relatedIdentifier element will give databases, which have an RRID, a metadata element that will enable them to assert who they are when releasing a DOI for a dataset.
Do DOIs not have a place to store the Database, already?
Yes and no, some databases like SPARC or Dryad, have a name that is unique to these projects and their datasets are findable by searching for this name, but other databases like the ODC-Sci and ODC-TBI (open data commons for spinal cord injury and traumatic brain injury) are simply listed as being from UC San Diego along with about 50 of their friends from earth sciences to biomedicine, which is true but not very specific.
The RRID project has been tracking databases, like SPARC and ODC-Sci, for over a decade but did not track the datasets associated with these databases, so the update to the DataCite metadata schema is a first in a set of steps to better bring these bits of information together enabling the database and the data set to both be first class citizens among research products.