diff --git a/man/kpatch-build.1 b/man/kpatch-build.1
index 826cc3f..35bc3c3 100644
--- a/man/kpatch-build.1
+++ b/man/kpatch-build.1
@@ -47,6 +47,10 @@ effect.
    Keep scratch files in /tmp
    (can be specified multiple times)
 
+-e|--oot-module
+   Enable patching out-of-tree module,
+   specify current version of module
+
 --skip-cleanup
    Skip post-build cleanup