diff --git a/angularjs/angular.d.ts b/angularjs/angular.d.ts
index 10fb67a3f..8e5e2a007 100644
--- a/angularjs/angular.d.ts
+++ b/angularjs/angular.d.ts
@@ -173,7 +173,7 @@ declare module ng {
     // see http://docs.angularjs.org/api/ng.$rootScope.Scope
     ///////////////////////////////////////////////////////////////////////////
     interface IScope {
-        // Documentation says exp is optional, but actual implementaton counts on it
+        $apply(): any;
         $apply(exp: string): any;
         $apply(exp: (scope: IScope) => any): any;