diff --git a/.NOT_EDITED_HERE.txt b/.NOT_EDITED_HERE.txt
index 21fc28cd51..fcdc563bb6 100644
--- a/.NOT_EDITED_HERE.txt
+++ b/.NOT_EDITED_HERE.txt
@@ -20,6 +20,7 @@
 apidocs/
 compose/reference/
 docker-trusted-registry/reference/
+engine/extend/
 engine/reference/
 machine/reference/
 notary/reference/