diff --git a/entityreference_prepopulate.module b/entityreference_prepopulate.module
index 505d44bb957eb4676b8a976f5e763b8d8395652c..097dce021ff16185d6d9e6f9ddfd6a33051ec1b1 100644
--- a/entityreference_prepopulate.module
+++ b/entityreference_prepopulate.module
@@ -243,6 +243,7 @@ function entityreference_prepopulate_get_values($field, $instance, $validate = T
 
   if (!$ids || !$validate) {
     // No IDs foudn, or no validation is needed.
+    $cache[$identifier] = $ids;
     return $ids;
   }