diff --git a/scripts/imgtool/keys/general.py b/scripts/imgtool/keys/general.py
index f6b8a09..e8755f6 100644
--- a/scripts/imgtool/keys/general.py
+++ b/scripts/imgtool/keys/general.py
@@ -1,5 +1,7 @@
 """General key class."""
 
+# SPDX-License-Identifier: Apache-2.0
+
 import sys
 
 AUTOGEN_MESSAGE = "/* Autogenerated by imgtool.py, do not edit. */"