diff --git a/Observable.js b/Observable.js
index d80895f..6d659b1 100644
--- a/Observable.js
+++ b/Observable.js
@@ -215,9 +215,9 @@
 			 * @returns The value set.
 			 */
 			value: (function () {
-				function areSameValues(lhs, rhs) {
+				var areSameValues = Object.is || function (lhs, rhs) {
 					return lhs === rhs && (lhs !== 0 || 1 / lhs === 1 / rhs) || lhs !== lhs && rhs !== rhs;
-				}
+				};
 				return function (name, value) {
 					var type = name in this ? Observable.CHANGETYPE_UPDATE : Observable.CHANGETYPE_ADD,
 						oldValue = this[name],
diff --git a/ObservablePath.js b/ObservablePath.js
index 936ea68..bd0ee9f 100644
--- a/ObservablePath.js
+++ b/ObservablePath.js
@@ -11,16 +11,15 @@
 })(this, function (Observable, BindingSource) {
 	"use strict";
 
-	var EMPTY_OBJECT = {};
+	var EMPTY_OBJECT = {},
+		areSameValues = Object.is || function (lhs, rhs) {
+			return lhs === rhs && (lhs !== 0 || 1 / lhs === 1 / rhs) || lhs !== lhs && rhs !== rhs;
+		};
 
 	function getPathComps(path, create) {
 		return path === "" ? [] : typeof path.splice !== "function" ? path.split(".") : create ? path.slice() : path;
 	}
 
-	function areSameValues(lhs, rhs) {
-		return lhs === rhs && (lhs !== 0 || 1 / lhs === 1 / rhs) || lhs !== lhs && rhs !== rhs;
-	}
-
 	/**
 	 * @method module:liaison/ObservablePath.getObjectPath
 	 * @param {object} o An object.