--- a/src/pyams_content/shared/common/zmi/security.py	Thu Apr 12 16:42:57 2018 +0200
+++ b/src/pyams_content/shared/common/zmi/security.py	Thu Apr 12 17:45:09 2018 +0200
@@ -191,7 +191,7 @@
     @cached_property
     def principal_id(self):
         principal_id = self.request.params.get('principal_id') or \
-                       self.request.params.get('{0}{1}principal_id'.format(self.prefix, self.widgets.prefix))
+                       self.request.params.get('{0}widgets.principal_id'.format(self.prefix))
         if not principal_id:
             raise NotFound
         return principal_id