I discovered today that the UBL 2.1 distribution unintentionally includes an empty schema fragment documented here:

http://docs.oasis-open.org/ubl/os-UBL-2.1/UBL-2.1.html#S-DOCUMENTATION-METADATA-SCHEMA

This is a minor issue and has zero effect on validation, as it is a documentation schema that is not part of the schema import tree for UBL documents.

I'm unclear about the naissance of this schema fragment and I question its value ... how would it be used to validate metadata? Perhaps we should simply remove it in the next release of UBL.

Does anyone know its history?