diff --git a/app/CallingAllPapers/ConferenceImporter.php b/app/CallingAllPapers/ConferenceImporter.php
index 61993145..7ff96ed3 100644
--- a/app/CallingAllPapers/ConferenceImporter.php
+++ b/app/CallingAllPapers/ConferenceImporter.php
@@ -79,7 +79,9 @@ public function import(Event $event)
             $conference->rejected_at = now();
         }
 
-        $conference->save();
+        if ($conference->isDirty()) {
+            $conference->save();
+        }
 
         return $conference;
     }