diff --git a/data/types.go b/data/types.go
index 5ca525ce4..df306041a 100644
--- a/data/types.go
+++ b/data/types.go
@@ -125,21 +125,6 @@ func (t *Targets) TargetAddKey(key *Key) bool {
 	return changed
 }
 
-//DelegationAddKey check existence of a key,
-//Add it to Delegation's key filed if not exist
-/*
-func (d *Delegation) DelegationAddKey(key *Key) bool {
-	changed := false
-	for _, id := range key.IDs() {
-		if _, ok := d.Keys[id]; !ok {
-			changed = true
-			d.Keys[id] = key
-		}
-	}
-	return changed
-}
-*/
-
 // UniqueKeys returns the unique keys for each associated role.
 // We might have multiple key IDs that correspond to the same key.
 func (r Root) UniqueKeys() map[string][]*Key {