diff --git a/PROTOCOL.md b/PROTOCOL.md
index 2886d84..2d020ad 100644
--- a/PROTOCOL.md
+++ b/PROTOCOL.md
@@ -82,6 +82,10 @@ party had fixed in it. No transaction on chipnet carried more than one.)*
    released (rule 5), the `REG` must be in a later block than the confirmed
    release — the one-block gap.
 4. `UPD`: valid if some output of the tx carries the name's category.
+   A name whose certificate is held by the registry covenant answers only to
+   an `UPD` that states the covenant state (`c`) and whose claim matches the
+   certificate's address; it stops resolving once its grace period has
+   passed. See `PROTOCOL-ADDENDUM-covenant-names.md`. *(Chipnet, 2026-10-04.)*
 5. `REL`: valid if the name is registered, no output of the tx carries the
    name's category, and one input spends an output of an earlier beacon
    transaction that carries the certificate. The name leaves the index.