diff --git a/tools/regions.py b/tools/regions.py
index 53e8ba53b8..3cc8eb8e58 100644
--- a/tools/regions.py
+++ b/tools/regions.py
@@ -1,4 +1,5 @@
 # mbed SDK
+# SPDX-License-Identifier: Apache-2.0
 # Copyright (c) 2011-2013 ARM Limited
 #
 # Licensed under the Apache License, Version 2.0 (the "License");