Hi Katrin
while the list result list for lists looks a lot like the catalog search results, it's not working quite the same. Instead of using Zebra, it's build with SQL. That means that the sorting does work differently as well.
Koha is a grab bag - there are always new things inside that I didn't know about...
My guess would be it's using biblio.copyrightdate. I would check the contents of the columns and your Koha-to-MARC mappings for it. In 18.11 it's possible to map both 260$c and 264$c, but it's not done by default.
In Koha menu "Administration > Koha-zu-MARC-Mapping" I have found only the following mapping: Koha-Feld Tag Unterfeld Bib biblio.copyrightdate 260 c Erscheinungsjahr, Vertriebsjahr etc. I have now added: biblio.copyrightdate 264 c Datum der Herstellung, der Veröffentlichung, des Vertriebs oder des But still the list shows the same wrong sort order... Best wishes: Michael -- Geschäftsführer · Diplombibliothekar BBS, Informatiker eidg. Fachausweis Admin Kuhn GmbH · Pappelstrasse 20 · 4123 Allschwil · Schweiz T 0041 (0)61 261 55 61 · E mik@adminkuhn.ch · W www.adminkuhn.ch