diff --git a/lib/Doctrine/ORM/Proxy/ProxyFactory.php b/lib/Doctrine/ORM/Proxy/ProxyFactory.php
index 6bc7dc5272a..16cfde9317a 100644
--- a/lib/Doctrine/ORM/Proxy/ProxyFactory.php
+++ b/lib/Doctrine/ORM/Proxy/ProxyFactory.php
@@ -91,7 +91,9 @@ public function __construct(EntityManagerInterface $em, $proxyDir, $proxyNs, $au
     protected function skipClass(ClassMetadata $metadata)
     {
         /* @var $metadata \Doctrine\ORM\Mapping\ClassMetadataInfo */
-        return $metadata->isMappedSuperclass || $metadata->getReflectionClass()->isAbstract();
+        return $metadata->isMappedSuperclass
+            || $metadata->isEmbeddedClass
+            || $metadata->getReflectionClass()->isAbstract();
     }
 
     /**
diff --git a/tests/Doctrine/Tests/ORM/Proxy/ProxyFactoryTest.php b/tests/Doctrine/Tests/ORM/Proxy/ProxyFactoryTest.php
index 739a41f1807..d66326faf2f 100644
--- a/tests/Doctrine/Tests/ORM/Proxy/ProxyFactoryTest.php
+++ b/tests/Doctrine/Tests/ORM/Proxy/ProxyFactoryTest.php
@@ -75,6 +75,33 @@ public function testReferenceProxyDelegatesLoadingToThePersister()
         $proxy->getDescription();
     }
 
+    public function testSkipMappedSuperClassesOnGeneration(): void
+    {
+        $cm = new ClassMetadata(\stdClass::class);
+        $cm->isMappedSuperclass = true;
+
+        self::assertSame(
+            0,
+            $this->proxyFactory->generateProxyClasses([$cm]),
+            'No proxies generated.'
+        );
+    }
+
+    /**
+     * @group 6625
+     */
+    public function testSkipEmbeddableClassesOnGeneration(): void
+    {
+        $cm = new ClassMetadata(\stdClass::class);
+        $cm->isEmbeddedClass = true;
+
+        self::assertSame(
+            0,
+            $this->proxyFactory->generateProxyClasses([$cm]),
+            'No proxies generated.'
+        );
+    }
+
     /**
      * @group DDC-1771
      */