diff --git a/intermud/doc/intermud-v25.rst b/intermud/doc/intermud-v25.rst
index dfac79f..4388317 100644
--- a/intermud/doc/intermud-v25.rst
+++ b/intermud/doc/intermud-v25.rst
@@ -312,6 +312,11 @@
 Combined with the default HMAC secret the second possibility enables peers to
 upgrade from the default secret to a specific one at any time.
 
+Which peers to inform about the secret, depends on the operator preferences.
+It may depend on a trust score the operator assigns or it may be sent to peers
+that are around for a certain time.
+
+
 Defined system headers / fields
 ===============================
 The fields defined in this section **MUST NOT** be used in any application sending