diff --git a/src/alert/alert.js b/src/alert/alert.js
index 3fa9633abf..b1fda4ec83 100644
--- a/src/alert/alert.js
+++ b/src/alert/alert.js
@@ -1,7 +1,7 @@
 angular.module('ui.bootstrap.alert', [])
 
 .controller('AlertController', ['$scope', '$attrs', function ($scope, $attrs) {
-  $scope.closeable = 'close' in $attrs;
+  $scope.closeable = !!$attrs.close;
   this.close = $scope.close;
 }])