diff --git a/doc/notes/notes-9.19.13.rst b/doc/notes/notes-9.19.13.rst
index 2565c37a59..a88b3179c3 100644
--- a/doc/notes/notes-9.19.13.rst
+++ b/doc/notes/notes-9.19.13.rst
@@ -45,6 +45,10 @@ Bug Fixes
   as broken and is not contacted again during a given resolution
   process. :gl:`#4005`
 
+- When removing delegations from an opt-out range, empty-non-terminal
+  NSEC3 records generated by those delegations were not cleaned up. This
+  has been fixed. :gl:`#4027`
+
 - A flaw in reworked code responsible for accepting TCP connections has
   been addressed. This issue could cause a visible performance drop for
   TCP queries on some platforms, notably FreeBSD, and has now been