diff --git a/factorio/factorio/egg-factorio.json b/factorio/factorio/egg-factorio.json
index 8ab979fe..33ea3b07 100644
--- a/factorio/factorio/egg-factorio.json
+++ b/factorio/factorio/egg-factorio.json
@@ -120,7 +120,7 @@
             "default_value": "",
             "user_viewable": 1,
             "user_editable": 1,
-            "rules": "string|max:30"
+            "rules": "nullable|string|max:30"
         }
     ]
 }