diff --git a/htdocs/expedition/class/expedition.class.php b/htdocs/expedition/class/expedition.class.php
index 1079f834024..b9b21899b28 100644
--- a/htdocs/expedition/class/expedition.class.php
+++ b/htdocs/expedition/class/expedition.class.php
@@ -1242,7 +1242,7 @@ class Expedition extends CommonObject
 
 					$mouvS = new MouvementStock($this->db);
 					// we do not log origin because it will be deleted
-					$mouvS->origin = null;
+					$mouvS->origin = '';
 					// get lot/serial
 					$lotArray = null;
 					if (isModEnabled('productbatch')) {
@@ -1440,7 +1440,7 @@ class Expedition extends CommonObject
 
 					$mouvS = new MouvementStock($this->db);
 					// we do not log origin because it will be deleted
-					$mouvS->origin = null;
+					$mouvS->origin = '';
 					// get lot/serial
 					$lotArray = $shipmentlinebatch->fetchAll($obj->expeditiondet_id);
 					if (!is_array($lotArray)) {