diff --git a/helpdesk/views/staff.py b/helpdesk/views/staff.py
index 1e09328b..c1a9b388 100644
--- a/helpdesk/views/staff.py
+++ b/helpdesk/views/staff.py
@@ -510,7 +510,7 @@ def update_ticket(request, ticket_id, public=False):
     # render the neutralized template
     comment = template_func(comment).render(context)
 
-    if owner is -1 and ticket.assigned_to:
+    if owner == -1 and ticket.assigned_to:
         owner = ticket.assigned_to.id
 
     f = FollowUp(ticket=ticket, date=timezone.now(), comment=comment,
@@ -524,7 +524,7 @@ def update_ticket(request, ticket_id, public=False):
     reassigned = False
 
     old_owner = ticket.assigned_to
-    if owner is not -1:
+    if owner != -1:
         if owner != 0 and ((ticket.assigned_to and owner != ticket.assigned_to.id) or not ticket.assigned_to):
             new_user = User.objects.get(id=owner)
             f.title = _('Assigned to %(username)s') % {