Referring a question in bug 5572 to the Koha list for further comments from the list. Bug 5572 introduces a refinement on authority merging. (Copying the change of an authority to the related biblio records.) Janusz (author of the patch) wrote: The original behavior in 3.0 was: when authority has been changed, then in the corresponding fields in the bibliographic records all the subfields of such fields controlled by authority will be dropped and created anew with only subfields which have a value in the authority. The new behavior is much better: in the bibliographic record only subfields which have a value in the authority_to (the new authority) will be changed. BUT what if there was a subfield present (with value) in authority (and in bibliographic) and the value is now deleted form authority? It will still stay in all bibliographic, whereas it should not. Hence my proposal: subfields not active in authority framework will be preserved; subfields active in the authority framework (i.e. controlled by this authority type) should be set as in the authority record - either have the value of corresponding subfield in authority or be empty. Marcel (tester of patch) commented: Tested your patch: it works as described. I see your point when you should clear a subfield at the authority side and you want to see the same at the biblio side. [How often would that happen?] However, if the subfield was already empty at the authority side and you update the auth record, do you also want to clear at that moment any possible info in that subfield at the biblio side? Does an empty authority subfield that is "not in the ignore tab" in the framework, really mean that that subfield should always be empty too at the biblio side? I am not sure about that; I will copy this comment to the Koha list for possible further discussion. What do you think? Thanks for further clarification.