diff --git a/app/controllers/oer/mymaterial.php b/app/controllers/oer/mymaterial.php
index a240645c37c64fc7e05d6ba1b3d770e29711b1bc..57eace096e8ba33fe2d1918c1200c467631985c2 100644
--- a/app/controllers/oer/mymaterial.php
+++ b/app/controllers/oer/mymaterial.php
@@ -212,7 +212,7 @@ class Oer_MymaterialController extends AuthenticatedController
             _('Zugriffszahlen für %s'),
             $material->name
         ));
-        if (!$GLOBALS['perm']->have_perm('root') && $material->user_id && $material->user_id !== $GLOBALS['user']->id) {
+        if (!$GLOBALS['perm']->have_perm('root') && !$material->isMine()) {
             throw new AccessDeniedException();
         }
         if (Request::get("export")) {