diff --git a/modules/stock_lot/stock.py b/modules/stock_lot/stock.py
index 077fe78cb2..2b61108fd8 100644
--- a/modules/stock_lot/stock.py
+++ b/modules/stock_lot/stock.py
@@ -126,7 +126,7 @@ class Lot(DeactivableMixin, ModelSQL, ModelView, LotMixin, StockMixin):
         pool = Pool()
         Move = pool.get('stock.move')
 
-        def find_moves(cls, state=None):
+        def find_moves(state=None):
             domain = [
                 ('lot', 'in', lots)
                 ]