diff --git a/lib-3rd-party/Sudzy/Engine.php b/lib-3rd-party/Sudzy/Engine.php
index e00455c780..1ca2c38db1 100644
--- a/lib-3rd-party/Sudzy/Engine.php
+++ b/lib-3rd-party/Sudzy/Engine.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Sudzy;
+namespace MailPoetVendor\Sudzy;
 
 /**
  * Singleton valdation engine
diff --git a/lib-3rd-party/Sudzy/ValidModel.php b/lib-3rd-party/Sudzy/ValidModel.php
index 01d5f1044d..99cd717f6c 100644
--- a/lib-3rd-party/Sudzy/ValidModel.php
+++ b/lib-3rd-party/Sudzy/ValidModel.php
@@ -1,5 +1,5 @@
 <?php
-namespace Sudzy;
+namespace MailPoetVendor\Sudzy;
 
 use MailPoetVendor\Paris\Model;
 
@@ -147,7 +147,7 @@ abstract class ValidModel extends Model {
   // Protected methods
   protected function doValidationError($context) {
     if ($context == $this->_validationOptions['throw']) {
-      throw new \Sudzy\ValidationException($this->_validationErrors);
+      throw new \MailPoetVendor\Sudzy\ValidationException($this->_validationErrors);
     }
   }
 
@@ -171,6 +171,6 @@ abstract class ValidModel extends Model {
   }
 
   protected function setupValidationEngine() {
-    if (null == $this->_validator) $this->_validator = new \Sudzy\Engine(); // Is lazy setup worth it?
+    if (null == $this->_validator) $this->_validator = new \MailPoetVendor\Sudzy\Engine(); // Is lazy setup worth it?
   }
 }
diff --git a/lib-3rd-party/Sudzy/ValidationException.php b/lib-3rd-party/Sudzy/ValidationException.php
index d11932ce88..18b1a3085f 100644
--- a/lib-3rd-party/Sudzy/ValidationException.php
+++ b/lib-3rd-party/Sudzy/ValidationException.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Sudzy;
+namespace MailPoetVendor\Sudzy;
 
 class ValidationException extends \Exception
 {
diff --git a/lib/Config/RequirementsChecker.php b/lib/Config/RequirementsChecker.php
index 0520658aa8..50b8b56ffe 100644
--- a/lib/Config/RequirementsChecker.php
+++ b/lib/Config/RequirementsChecker.php
@@ -16,9 +16,6 @@ class RequirementsChecker {
   public $display_error_notice;
   public $vendor_classes = [
     '\Carbon\Carbon',
-    '\Sudzy\ValidModel',
-    '\Sudzy\ValidationException',
-    '\Sudzy\Engine',
     '\pQuery',
     '\Cron\CronExpression',
     '\Html2Text\Html2Text',
diff --git a/lib/Models/Model.php b/lib/Models/Model.php
index 518edb5f5b..d9881ae895 100644
--- a/lib/Models/Model.php
+++ b/lib/Models/Model.php
@@ -124,7 +124,7 @@ use MailPoet\WP\Functions as WPFunctions;
  * @property string|null $id
  */
 
-class Model extends \Sudzy\ValidModel {
+class Model extends \MailPoetVendor\Sudzy\ValidModel {
   const DUPLICATE_RECORD = 23000;
 
   public static $_table;
@@ -221,7 +221,7 @@ class Model extends \Sudzy\ValidModel {
     $this->_new_record = $this->isNew();
     try {
       parent::save();
-    } catch (\Sudzy\ValidationException $e) {
+    } catch (\MailPoetVendor\Sudzy\ValidationException $e) {
       $this->setError($e->getValidationErrors());
     } catch (\PDOException $e) {
       switch ($e->getCode()) {
diff --git a/lib/Models/ModelValidator.php b/lib/Models/ModelValidator.php
index 48aea9599e..3db9d5f8b8 100644
--- a/lib/Models/ModelValidator.php
+++ b/lib/Models/ModelValidator.php
@@ -5,7 +5,7 @@ namespace MailPoet\Models;
 use MailPoet\Util\Helpers;
 use MailPoet\WP\Functions as WPFunctions;
 
-class ModelValidator extends \Sudzy\Engine {
+class ModelValidator extends \MailPoetVendor\Sudzy\Engine {
   public $validators;
 
   const EMAIL_MIN_LENGTH = 6;