diff --git a/PageTree/PageTreeRouteUpdateHandler.php b/PageTree/PageTreeRouteUpdateHandler.php
index 82259edf1..b16e79207 100644
--- a/PageTree/PageTreeRouteUpdateHandler.php
+++ b/PageTree/PageTreeRouteUpdateHandler.php
@@ -16,11 +16,12 @@
 use Sulu\Bundle\ContentBundle\Document\BasePageDocument;
 use Sulu\Component\DocumentManager\DocumentManagerInterface;
 use Symfony\Component\OptionsResolver\OptionsResolver;
+use Task\Lock\LockingTaskHandlerInterface;
 
 /**
  * Task-Handler to update page-tree-routes.
  */
-class PageTreeRouteUpdateHandler implements AutomationTaskHandlerInterface
+class PageTreeRouteUpdateHandler implements AutomationTaskHandlerInterface, LockingTaskHandlerInterface
 {
     /**
      * @var PageTreeUpdaterInterface
@@ -79,4 +80,12 @@ public function handle($workload)
 
         $this->documentManager->flush();
     }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getLockKey($workload)
+    {
+        return self::class;
+    }
 }