diff --git a/application/symfony/src/Domain/SourceManagement/SourceMetaInformation.php b/application/symfony/src/Domain/SourceManagement/SourceMetaInformation.php
index cb98b89..8ef76c6 100644
--- a/application/symfony/src/Domain/SourceManagement/SourceMetaInformation.php
+++ b/application/symfony/src/Domain/SourceManagement/SourceMetaInformation.php
@@ -4,6 +4,7 @@ namespace App\Domain\SourceManagement;
 
 use App\Domain\EntityManagement\EntityMetaInformation;
 use App\Entity\Source\AbstractSource;
+use App\Exception\NotCorrectInstanceException;
 
 /**
  * @author kevinfrantz
@@ -22,7 +23,7 @@ final class SourceMetaInformation extends EntityMetaInformation implements Sourc
     public function __construct(\App\Entity\EntityInterface $entity)
     {
         if (!$entity instanceof AbstractSource) {
-            throw new \TypeError('Entity has to be an instance of '.AbstractSource::class);
+            throw new NotCorrectInstanceException('Entity has to be an instance of '.AbstractSource::class);
         }
         parent::__construct($entity);
     }
diff --git a/application/symfony/src/Exception/NotCorrectInstanceException.php b/application/symfony/src/Exception/NotCorrectInstanceException.php
new file mode 100644
index 0000000..1546858
--- /dev/null
+++ b/application/symfony/src/Exception/NotCorrectInstanceException.php
@@ -0,0 +1,7 @@
+<?php
+
+namespace App\Exception;
+
+class NotCorrectInstanceException extends \TypeError
+{
+}
diff --git a/application/symfony/tests/Unit/Domain/SourceManagement/SourceMetaInformationTest.php b/application/symfony/tests/Unit/Domain/SourceManagement/SourceMetaInformationTest.php
index 97fa270..c6ac1b2 100644
--- a/application/symfony/tests/Unit/Domain/SourceManagement/SourceMetaInformationTest.php
+++ b/application/symfony/tests/Unit/Domain/SourceManagement/SourceMetaInformationTest.php
@@ -10,6 +10,8 @@ use App\Domain\SourceManagement\SourceMetaInformation;
 use App\Domain\SourceManagement\SourceMetaInformationInterface;
 use App\Domain\TemplateManagement\TemplatePathFormAndViewInterface;
 use App\Domain\FormManagement\FormMetaInformationInterface;
+use App\Entity\EntityInterface;
+use App\Exception\NotCorrectInstanceException;
 
 class SourceMetaInformationTest extends TestCase
 {
@@ -79,4 +81,10 @@ class SourceMetaInformationTest extends TestCase
     {
         $this->assertInstanceOf(FormMetaInformationInterface::class, $this->sourceMetaInformation->getFormMetaInformation());
     }
+
+    public function testTypeError(): void
+    {
+        $this->expectException(NotCorrectInstanceException::class);
+        new SourceMetaInformation($this->createMock(EntityInterface::class));
+    }
 }