diff --git a/js/libtextsecure.js b/js/libtextsecure.js
index 8b2d9c86d..9fe4b6b49 100644
--- a/js/libtextsecure.js
+++ b/js/libtextsecure.js
@@ -139,7 +139,8 @@
         var finalMessage = textsecure.protobuf.PushMessageContent.decode(res[0]);
 
         if ((finalMessage.flags & textsecure.protobuf.PushMessageContent.Flags.END_SESSION)
-                == textsecure.protobuf.PushMessageContent.Flags.END_SESSION)
+                == textsecure.protobuf.PushMessageContent.Flags.END_SESSION &&
+				finalMessage.sync !== null)
             res[1]();
 
         return finalMessage;
diff --git a/libtextsecure/axolotl_wrapper.js b/libtextsecure/axolotl_wrapper.js
index 379fcc96c..a9f5959de 100644
--- a/libtextsecure/axolotl_wrapper.js
+++ b/libtextsecure/axolotl_wrapper.js
@@ -62,7 +62,8 @@
         var finalMessage = textsecure.protobuf.PushMessageContent.decode(res[0]);
 
         if ((finalMessage.flags & textsecure.protobuf.PushMessageContent.Flags.END_SESSION)
-                == textsecure.protobuf.PushMessageContent.Flags.END_SESSION)
+                == textsecure.protobuf.PushMessageContent.Flags.END_SESSION &&
+				finalMessage.sync !== null)
             res[1]();
 
         return finalMessage;