diff --git a/address.py b/address.py
index 4043e35903..9d0d050eb5 100644
--- a/address.py
+++ b/address.py
@@ -112,12 +112,12 @@ class Address(ModelSQL, ModelView):
 
     def on_change_country(self, vals):
         subdivision_obj = Pool().get('country.subdivision')
-        result = dict((k, vals.get(k, False))
+        result = dict((k, vals.get(k))
             for k in ('country', 'subdivision'))
         if vals['subdivision']:
             subdivision = subdivision_obj.browse(vals['subdivision'])
             if subdivision.country.id != vals['country']:
-                result['subdivision'] = False
+                result['subdivision'] = None
         return result
 
 Address()
diff --git a/party.py b/party.py
index d2528b50fa..e0b0e7fbdc 100644
--- a/party.py
+++ b/party.py
@@ -184,8 +184,8 @@ class Party(ModelSQL, ModelView):
         if default is None:
             default = {}
         default = default.copy()
-        default['code'] = False
-        default['addresses'] = False
+        default['code'] = None
+        default['addresses'] = None
         new_ids = []
         for party in self.browse(ids):
             new_id = super(Party, self).copy(party.id, default=default)
@@ -216,7 +216,7 @@ class Party(ModelSQL, ModelView):
             [("party", "=", party_id), ("active", "=", True)],
             order=[('sequence', 'ASC'), ('id', 'ASC')])
         if not address_ids:
-            return False
+            return None
         default_address = address_ids[0]
         if not type:
             return default_address