diff --git a/reclass/datatypes/parameters.py b/reclass/datatypes/parameters.py
index c935000..cc0c74c 100644
--- a/reclass/datatypes/parameters.py
+++ b/reclass/datatypes/parameters.py
@@ -55,6 +55,7 @@
         self._escapes_handled = {}
         self._has_inv_query = False
         self._options = options
+        self._keep_overrides = False
         if mapping is not None:
             # we initialise by merging
             self._keep_overrides = True