diff --git a/tinycrypt/ecc.c b/tinycrypt/ecc.c
index ab1956a..1f32170 100644
--- a/tinycrypt/ecc.c
+++ b/tinycrypt/ecc.c
@@ -4,6 +4,8 @@
  * 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,