diff --git a/Controller.php b/Controller.php
index 2f11218..44a071b 100644
--- a/Controller.php
+++ b/Controller.php
@@ -49,7 +49,7 @@ use phpOMS\Views\View;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Controller extends ModuleAbstract implements WebInterface
+final class Controller extends ModuleAbstract implements WebInterface
 {
 
     /**
diff --git a/Models/NullAccount.php b/Models/NullAccount.php
index 38bc049..b69c110 100644
--- a/Models/NullAccount.php
+++ b/Models/NullAccount.php
@@ -22,6 +22,6 @@ namespace Modules\Admin\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class NullAccount extends Account
+final class NullAccount extends Account
 {
 }
diff --git a/Models/NullAccountPermission.php b/Models/NullAccountPermission.php
index 23aa60f..8677096 100644
--- a/Models/NullAccountPermission.php
+++ b/Models/NullAccountPermission.php
@@ -22,6 +22,6 @@ namespace Modules\Admin\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class NullAccountPermission extends AccountPermission
+final class NullAccountPermission extends AccountPermission
 {
 }
diff --git a/Models/NullGroup.php b/Models/NullGroup.php
index d51489b..0140578 100644
--- a/Models/NullGroup.php
+++ b/Models/NullGroup.php
@@ -22,6 +22,6 @@ namespace Modules\Admin\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class NullGroup extends Group
+final class NullGroup extends Group
 {
 }
diff --git a/Models/NullGroupPermission.php b/Models/NullGroupPermission.php
index 58dc21f..acc4e64 100644
--- a/Models/NullGroupPermission.php
+++ b/Models/NullGroupPermission.php
@@ -22,6 +22,6 @@ namespace Modules\Admin\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class NullGroupPermission extends GroupPermission
+final class NullGroupPermission extends GroupPermission
 {
 }