diff --git a/src/babel/types/flow.js b/src/babel/types/flow.js
index c44e2f2b27..41781ecfe2 100644
--- a/src/babel/types/flow.js
+++ b/src/babel/types/flow.js
@@ -19,7 +19,6 @@ export function removeTypeDuplicates(nodes) {
   var generics = {};
   var bases = {};
 
-  var flattened = [];
   var types = [];
 
   for (var i = 0; i < nodes.length; i++) {