diff --git a/lodash.src.js b/lodash.src.js
index 88b3d7231..0464191dd 100644
--- a/lodash.src.js
+++ b/lodash.src.js
@@ -771,8 +771,8 @@
 
     /** Used to detect if a method is native. */
     var reIsNative = RegExp('^' +
-      escapeRegExp(objToString)
-      .replace(/toString|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
+      escapeRegExp(fnToString.call(hasOwnProperty))
+      .replace(/hasOwnProperty|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
     );
 
     /** Native method references. */