diff --git a/js/LinkedElementIO.js b/js/LinkedElementIO.js
index 3a933210..7aa75ed6 100644
--- a/js/LinkedElementIO.js
+++ b/js/LinkedElementIO.js
@@ -24,6 +24,7 @@ define( function( require ) {
 
   phetioInherit( ObjectIO, 'LinkedElementIO', LinkedElementIO, {}, {
     documentation: 'A LinkedElement',
+    validator: { isValidValue: () => true },
 
     /**
      * @param {LinkedElement} linkedElement
diff --git a/js/phetioInherit.js b/js/phetioInherit.js
index ca429d55..5c82f367 100644
--- a/js/phetioInherit.js
+++ b/js/phetioInherit.js
@@ -28,7 +28,9 @@ define( function( require ) {
 
     inherit( supertype, subtype, methods, staticProperties );
 
-    staticProperties = staticProperties || {};
+    assert && assert( staticProperties, 'static properties must be defined' );
+    assert && assert( staticProperties.validator, 'validator must be provided' );
+    ValidatorDef.validateValidator( staticProperties.validator );
 
     if ( staticProperties.parameterTypes ) {
       assert && assert( Array.isArray( staticProperties.parameterTypes ), 'parameterTypes expected to be array' );
@@ -38,11 +40,6 @@ define( function( require ) {
         .join( ', ' ) + '>';
     }
 
-    // TODO: isn't this field required? see https://github.com/phetsims/axon/issues/204
-    if( staticProperties.validator){
-      ValidatorDef.validateValidator( staticProperties.validator);
-    }
-
     // The method order is used to determine the ordering of the documentation for a type's methods, see Studio for usage.
     subtype.methodOrder = staticProperties.methodOrder || [];
     subtype.methodOrder.forEach( function( methodName ) {
diff --git a/js/types/ObjectIO.js b/js/types/ObjectIO.js
index 93950d9e..9e3aa21e 100644
--- a/js/types/ObjectIO.js
+++ b/js/types/ObjectIO.js
@@ -13,6 +13,7 @@ define( function( require ) {
   // modules
   var phetioInherit = require( 'TANDEM/phetioInherit' );
   var tandemNamespace = require( 'TANDEM/tandemNamespace' );
+  var validate = require( 'AXON/validate' );
 
   /**
    * Main constructor for ObjectIO base IO type.
@@ -30,6 +31,9 @@ define( function( require ) {
 
     // @public (read-only)
     this.phetioID = phetioID;
+
+    // Use the validator defined on the constructor to make sure the instance is valid
+    assert && validate( instance, this.constructor.validator );
   }
 
   // ObjectIO inherits from window.Object because it starts with its prototype in phetioInherit.inheritBase