diff --git a/build/wrapper.template.js b/build/wrapper.template.js
index 9bc8048984e..136dbd8711b 100644
--- a/build/wrapper.template.js
+++ b/build/wrapper.template.js
@@ -39,7 +39,7 @@
     for (var k in exportTo.shaka) {
       exports[k] = exportTo.shaka[k];
     }
-  } else if (typeof define != 'undefined' && define.amd) {
+  } else if (typeof define == 'function' && define.amd) {
     // AMD module loader.
     define(function(){
       return exportTo.shaka;