diff --git a/lib/6to5/traverse/index.js b/lib/6to5/traverse/index.js
index 51905eaf0a..214db9bc67 100644
--- a/lib/6to5/traverse/index.js
+++ b/lib/6to5/traverse/index.js
@@ -80,6 +80,7 @@ traverse.removeProperties = function (tree) {
     delete node.start;
     delete node.end;
     delete node.loc;
+    delete node.raw;
 
     clearComments(node.trailingComments);
     clearComments(node.leadingComments);