--- /dev/null
+<?php
+
+namespace Drupal\metatag\Plugin\DataType;
+
+use \Drupal\Core\TypedData\Plugin\DataType\StringData;
+
+/**
+ * The metatag data type.
+ *
+ * The plain value of a metatag is a serialized object represented as a string.
+ *
+ * @DataType(
+ * id = "metatag",
+ * label = @Translation("Metatag")
+ * )
+ */
+class Metatag extends StringData implements MetatagInterface {
+
+}