diff --git a/doc/copyright.texi b/doc/copyright.texi
index df0de10e8..5aeb3d6d8 100644
--- a/doc/copyright.texi
+++ b/doc/copyright.texi
@@ -208,6 +208,7 @@ SUCH DAMAGE.
 @end table
 
 @verbatim
+SPDX-License-Identifier: BSD-3-Clause
 
 Copyright (c) 2003-2011, PADL Software Pty Ltd.
 Copyright (c) 2004, Andrew Bartlett.