To recreate: Identify some records with multiple branch holdings. In tools, set up a CSV profile with a combination of bibliographic and item fields, for example: 001|952$c|952$a|952$f|952$7|245 From Cataloging -> Export data, export either a bibliographic range or list of biblionumbers. Select one library branch and select "Remove items not owned by selected libraries" checkbox. Export as CSV using your CSV profile. See that file includes branches other than the one you selected.