diff --git a/sapl/crud/base.py b/sapl/crud/base.py
index 0dc11ea5c..98af2a3bb 100644
--- a/sapl/crud/base.py
+++ b/sapl/crud/base.py
@@ -581,6 +581,8 @@ class CrudListView(PermissionRequiredContainerCrudMixin, ListView):
                                 rmo = rmo[0]
                                 if not isinstance(rmo, str):
                                     rmo = rmo[0]
+                                if rmo.startswith('-'):
+                                    rmo = rmo[1:]
                                 fo = '%s__%s' % (fo, rmo)
 
                         fo = desc + fo