diff --git a/utils/src/format.h b/utils/src/format.h
index fd0cbd62..7a02c26a 100644
--- a/utils/src/format.h
+++ b/utils/src/format.h
@@ -108,6 +108,7 @@ struct scoutfs_key {
 #define SCOUTFS_LINK_BACKREF_KEY	6
 #define SCOUTFS_SYMLINK_KEY		7
 #define SCOUTFS_BMAP_KEY		8
+#define SCOUTFS_ORPHAN_KEY		9
 
 #define SCOUTFS_MAX_ITEM_LEN 512