diff --git a/lib/sign.js b/lib/sign.js
index 1bd562e..7c6638d 100644
--- a/lib/sign.js
+++ b/lib/sign.js
@@ -4,7 +4,7 @@ var crypto = require('crypto');
 var sign = function(params, recurlyPrivateKey) {
 	
 	var timestamp = ~~(Date.now() / 1000);
-	var obj = {};
+	var obj = Object.create(null);
 	obj.nonce = crypto.createHash('sha1').update(timestamp+Math.random()+'').digest('hex'); // Create a randomised, time-based one-use number
 	
 	parseParams(obj, params, null);