diff --git a/types/express/index.d.ts b/types/express/index.d.ts
index 9b913db473..d48d58c0c9 100644
--- a/types/express/index.d.ts
+++ b/types/express/index.d.ts
@@ -2,6 +2,7 @@
 // Project: http://expressjs.com
 // Definitions by: Boris Yankov <https://github.com/borisyankov/>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+// TypeScript Version: 2.2
 
 /* =================== USAGE ===================