This is a followup from Bug 36054 and tested on a 23.11 and 24.05 installation. To recreate: 1. Edit the default framework and uncheck the mandatory box for the SUBFIELD of the 005 and save. The tag itself should still be marked as mandatory. 2. Find a bib record. 3. See the 005 is not required. Save. Note: In 23.11, it is possible to delete data in the 005 and save the record in the basic editor. As of 24.05, saving the record will automatically add data to the 005 in the basic editor if it is missing in the Default framework. The record saves as it should. 4. Now edit the record again and switch to the Advanced Editor. 5. Delete the 005 tag 6. Save. Save fails and gives an error statement "Record structure invalid, cannot save." and "missing mandatory tag: 005." If a tag is marked as mandatory, the subfields should be mandatory. If none of the subfields are mandatory, should the tag still be mandatory? The mandatory requirement highlights a relationship problem between the tag settings and subfield settings. This does raise some questions on how to handle things like the 942$c. This field is mandatory regardless of what the user selects in the framework.