diff --git a/specification/chaos/resource-manager/Microsoft.Chaos/preview/2021-09-15-preview/types/experiments.json b/specification/chaos/resource-manager/Microsoft.Chaos/preview/2021-09-15-preview/types/experiments.json
index 1892574e300e..a6e0fdca3900 100644
--- a/specification/chaos/resource-manager/Microsoft.Chaos/preview/2021-09-15-preview/types/experiments.json
+++ b/specification/chaos/resource-manager/Microsoft.Chaos/preview/2021-09-15-preview/types/experiments.json
@@ -13,7 +13,7 @@
       "in": "path",
       "required": true,
       "minLength": 1,
-      "pattern": "^[a-zA-Z0-9_\\-\\.]+$",
+      "pattern": "^[^<>%&:?#/\\\\]+$",
       "x-ms-parameter-location": "method"
     },
     "statusId": {