diff --git a/config/resources/domain.json b/config/resources/domain.json
index 51bd0a3..e56515d 100644
--- a/config/resources/domain.json
+++ b/config/resources/domain.json
@@ -383,6 +383,10 @@
         "valid": {
           "type": "boolean",
           "predicate": "ext:valid"
+        },
+        "ar-plichtig": {
+          "type":"boolean",
+          "predicate": "ext:arPlichtig"
         }
       },
       "relationships": {