diff --git a/addons/stock/wizard/stock_change_product_qty.py b/addons/stock/wizard/stock_change_product_qty.py
index d2b9a2a5eb8..c22ade231be 100644
--- a/addons/stock/wizard/stock_change_product_qty.py
+++ b/addons/stock/wizard/stock_change_product_qty.py
@@ -28,7 +28,7 @@ class stock_change_product_qty(osv.osv_memory):
     _columns = {
         'product_id' : fields.many2one('product.product', 'Product'),
         'new_quantity': fields.float('Quantity', required=True, help='This quantity is expressed in the Default UoM of the product.'),
-        'prodlot_id': fields.many2one('stock.production.lot', 'Production Lot', required=True,domain="[('product_id','=',product_id)]"),
+        'prodlot_id': fields.many2one('stock.production.lot', 'Production Lot', domain="[('product_id','=',product_id)]"),
         'location_id': fields.many2one('stock.location', 'Location', required=True, domain="[('usage', '=', 'internal')]"),
     }