diff --git a/utils_maintenance/header_clean.py b/utils_maintenance/header_clean.py
index 9fb4e133e30be332a19ebda403b976977332a2ea..0ae397e23a9faad889f9eaac2cf24fb5096f8b76 100755
--- a/utils_maintenance/header_clean.py
+++ b/utils_maintenance/header_clean.py
@@ -404,6 +404,7 @@ def create_parser():
         nargs='+',
         required=False,
         metavar="REGEX",
+        default=(),
         help="Match file paths against this expression",
     )
     return parser