diff --git a/validator.conf.sample.in b/validator.conf.sample.in
index 4bc401f..1793354 100644
--- a/validator.conf.sample.in
+++ b/validator.conf.sample.in
@@ -18,7 +18,7 @@
       {
         k-regex ^([^<NDNS>]*)<NDNS>(<>*)<KEY><>$
         k-expand \\1\\2
-        h-relation is-prefix-of ; ksk should be signed by dkey in parent zone
+        h-relation equal ; ksk should be signed by dkey in parent zone
         p-regex ^([^<NDNS>]*)<NDNS><KEY><><><>$
         p-expand \\1
       }