diff --git a/addons/sale/stock.py b/addons/sale/stock.py
index 378af21c1b4..653b147d3d0 100644
--- a/addons/sale/stock.py
+++ b/addons/sale/stock.py
@@ -135,7 +135,7 @@ class stock_picking(osv.osv):
 
         for picking in picking_obj.browse(cursor, user, picking_ids,
                 context=context):
-            if not picking.sale_id:
+            if not picking.sale_id or picking.backorder_id:
                 continue
             sale_lines = picking.sale_id.order_line
             invoice_created = invoices[result[picking.id]]
@@ -195,4 +195,4 @@ class stock_picking(osv.osv):
                     })
         return result
 
-# vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4:
+# vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4:
\ No newline at end of file