diff --git a/achievements.api.php b/achievements.api.php
index 9515192242e7f1b5d25813b1819c75c351a762b5..74b0ed9190b195504987a87ff01827a9f00f748d 100644
--- a/achievements.api.php
+++ b/achievements.api.php
@@ -258,7 +258,8 @@ function example_query_alter(QueryAlterableInterface $query) {
  *   The user ID whose access is being questioned.
  *
  * @return
- *   TRUE if the $uid can earn achievements, FALSE if they can't.
+ *   TRUE if the $uid can earn achievements, FALSE if they can't,
+ *   or NULL if there's no change to the user's default access.
  */
 function example_achievements_access_earn($uid) {
   $account = user_load($uid);
diff --git a/achievements_optout/achievements_optout.module b/achievements_optout/achievements_optout.module
index 9390884e85234419fd22cf866b813bd6c627d719..0ca3d2b8d50c76b474807ce64ef591ebc60bb4e9 100644
--- a/achievements_optout/achievements_optout.module
+++ b/achievements_optout/achievements_optout.module
@@ -44,6 +44,11 @@ function achievements_optout_achievements_access_earn($uid) {
     ->fieldCondition('achievements_optout', 'value', 1);
   $result = $query->execute();
 
-  // results? you opted for no access.
-  return count($result) ? FALSE : TRUE;
+  // they've opted out.
+  if (count($result)) {
+    return FALSE;
+  }
+
+  // NULL for "no change".
+  return NULL;
 }
\ No newline at end of file