diff --git a/scripts/JSON_data_files_validator.py b/scripts/JSON_data_files_validator.py
index 63daa81e21..bacf268dde 100644
--- a/scripts/JSON_data_files_validator.py
+++ b/scripts/JSON_data_files_validator.py
@@ -115,7 +115,8 @@ def _get_valid_schema(self) -> Schema:
                                 },
                                 'bytes': float
                             }
-                        ]
+                        ],
+                        Optional('user_defined'): dict
                     },
                 ]
             }