diff --git a/client/static/xsd/cnxml.xsd b/client/static/xsd/cnxml.xsd
index 80f2a42f..e5baab8e 100644
--- a/client/static/xsd/cnxml.xsd
+++ b/client/static/xsd/cnxml.xsd
@@ -41,6 +41,14 @@
         </xs:simpleType>
       </xs:attribute>
       <xs:attribute name="module-id"/>
+      <xs:attribute name="noindex">
+        <xs:simpleType>
+          <xs:restriction base="xs:token">
+            <xs:enumeration value="true"/>
+            <xs:enumeration value="false"/>
+          </xs:restriction>
+        </xs:simpleType>
+      </xs:attribute>
     </xs:complexType>
   </xs:element>
   <xs:group name="title">