diff --git a/src/Marello/Bundle/ShippingBundle/Entity/HasShipmentTrait.php b/src/Marello/Bundle/ShippingBundle/Entity/HasShipmentTrait.php
index 9a928bbcf..b6c67ea9f 100644
--- a/src/Marello/Bundle/ShippingBundle/Entity/HasShipmentTrait.php
+++ b/src/Marello/Bundle/ShippingBundle/Entity/HasShipmentTrait.php
@@ -20,11 +20,11 @@ public function getShipment()
     }
 
     /**
-     * @param Shipment $shipment
+     * @param null|Shipment $shipment
      *
      * @return $this
      */
-    public function setShipment(Shipment $shipment)
+    public function setShipment(?Shipment $shipment = null)
     {
         $this->shipment = $shipment;
 
diff --git a/src/Marello/Bundle/ShippingBundle/Integration/ShippingAwareInterface.php b/src/Marello/Bundle/ShippingBundle/Integration/ShippingAwareInterface.php
index 6eab4ec1a..e339ee7ea 100644
--- a/src/Marello/Bundle/ShippingBundle/Integration/ShippingAwareInterface.php
+++ b/src/Marello/Bundle/ShippingBundle/Integration/ShippingAwareInterface.php
@@ -8,5 +8,5 @@ interface ShippingAwareInterface
 {
     public function getShipment();
 
-    public function setShipment(Shipment $shipment);
+    public function setShipment(?Shipment $shipment);
 }