diff --git a/polymer-micro.html b/polymer-micro.html
index 61a8e3d4..041b032a 100644
--- a/polymer-micro.html
+++ b/polymer-micro.html
@@ -8,7 +8,7 @@ Code distributed by Google as part of the polymer project is also
 subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
 -->
 <link rel="import" href="src/polymer-lib.html">
-
+<link rel="import" href="src/micro/tag.html">
 <link rel="import" href="src/micro/mixins.html">
 <link rel="import" href="src/micro/extends.html">
 <link rel="import" href="src/micro/constructor.html">
@@ -20,6 +20,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
   Polymer.Base.addFeature({
 
     registerFeatures: function() {
+      this._prepIs();
       this._prepMixins();
       this._prepExtends();
       this._prepConstructor();
diff --git a/polymer-mini.html b/polymer-mini.html
index d0880a51..9032bd80 100644
--- a/polymer-mini.html
+++ b/polymer-mini.html
@@ -22,6 +22,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
   Polymer.Base.addFeature({
 
     registerFeatures: function() {
+      this._prepIs();
       this._prepMixins();
       this._prepExtends();
       this._prepConstructor();
diff --git a/polymer.html b/polymer.html
index 674bef3f..0bdf74b5 100644
--- a/polymer.html
+++ b/polymer.html
@@ -25,6 +25,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
   Polymer.Base.addFeature({
 
     registerFeatures: function() {
+      this._prepIs();
       this._prepMixins();
       this._prepExtends();
       this._prepConstructor();