diff --git a/package.json b/package.json
index fcbb5e1..02f5a35 100644
--- a/package.json
+++ b/package.json
@@ -44,7 +44,7 @@
     "grunt-contrib-jshint": "^1.1.0",
     "grunt-contrib-nodeunit": "^1.0.0",
     "grunt-contrib-qunit": "^2.0.0",
-    "grunt-contrib-uglify": "^3.0.0",
+    "grunt-contrib-uglify": "^4.0.0",
     "grunt-contrib-watch": "^1.0.0"
   },
   "lib": ".",