diff --git a/zerver/lib/user_groups.py b/zerver/lib/user_groups.py
index 24180ec74e..61fdd14acb 100644
--- a/zerver/lib/user_groups.py
+++ b/zerver/lib/user_groups.py
@@ -269,14 +269,18 @@ def user_groups_in_realm_serialized(realm: Realm) -> List[UserGroupDict]:
             can_mention_group=user_group.can_mention_group_id,
         )
 
-    membership = UserGroupMembership.objects.filter(user_group__realm=realm).values_list(
-        "user_group_id", "user_profile_id"
+    membership = (
+        UserGroupMembership.objects.filter(user_group__realm=realm)
+        .exclude(user_group__named_user_group=None)
+        .values_list("user_group_id", "user_profile_id")
     )
     for user_group_id, user_profile_id in membership:
         group_dicts[user_group_id]["members"].append(user_profile_id)
 
-    group_membership = GroupGroupMembership.objects.filter(subgroup__realm=realm).values_list(
-        "subgroup_id", "supergroup_id"
+    group_membership = (
+        GroupGroupMembership.objects.filter(subgroup__realm=realm)
+        .exclude(supergroup__named_user_group=None)
+        .values_list("subgroup_id", "supergroup_id")
     )
     for subgroup_id, supergroup_id in group_membership:
         group_dicts[supergroup_id]["direct_subgroup_ids"].append(subgroup_id)