diff --git a/docs/tutorials/security-validator-config.rst b/docs/tutorials/security-validator-config.rst
index 69edc45..ae2775c 100644
--- a/docs/tutorials/security-validator-config.rst
+++ b/docs/tutorials/security-validator-config.rst
@@ -317,7 +317,7 @@
         type name
         hyper-relation
         {
-          k-regex ^(<>*)<KEY><>$
+          k-regex ^(<>*)<KEY><>{1,3}$
           k-expand \\1
           h-relation is-prefix-of
           p-regex ^(<>*)$