diff --git a/pybis/src/python/pybis/pybis.py b/pybis/src/python/pybis/pybis.py
index 7ada76fa80f5a30a21d2f731155aec08231a0282..db8126bac2af231805f998aec1d6c00b03cd3ab0 100644
--- a/pybis/src/python/pybis/pybis.py
+++ b/pybis/src/python/pybis/pybis.py
@@ -1208,7 +1208,7 @@ class Openbis:
         fetchopts = fetch_option['authorizationGroup']
         fetchopts['from'] = start_with
         fetchopts['count'] = count
-        for option in ['roleAssignment', 'registrator', 'users']:
+        for option in ['roleAssignments', 'registrator', 'users']:
             fetchopts[option] = fetch_option[option]
         request = {
             "method": "searchAuthorizationGroups",