diff --git a/lib/6to5/transformers/classes.js b/lib/6to5/transformers/classes.js
index f207a9c8ba..d358409a29 100644
--- a/lib/6to5/transformers/classes.js
+++ b/lib/6to5/transformers/classes.js
@@ -24,15 +24,9 @@ var buildClass = function (node, generateUid) {
   var superName = node.superClass;
   var className = node.id;
 
-  if (superName) {
-    if (superName.type === "Literal" && superName.value === null) {
-      superName = null;
-    }
-  }
-
   var noName = false;
   if (!className) {
-    className = b.identifier(generateUid("_class"));
+    className = b.identifier(generateUid("class"));
     noName = true;
   }