diff --git a/tinycrypt/ecc_dsa.c b/tinycrypt/ecc_dsa.c
index 3743091..c093ebe 100644
--- a/tinycrypt/ecc_dsa.c
+++ b/tinycrypt/ecc_dsa.c
@@ -3,6 +3,8 @@
 /* Copyright (c) 2014, Kenneth MacKay
  * All rights reserved.
  *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *  * Redistributions of source code must retain the above copyright notice,