diff --git a/include/tl/expected.hpp b/include/tl/expected.hpp
index 31a5193..a46c699 100644
--- a/include/tl/expected.hpp
+++ b/include/tl/expected.hpp
@@ -11,6 +11,9 @@
 // You should have received a copy of the CC0 Public Domain Dedication
 // along with this software. If not, see
 // <http://creativecommons.org/publicdomain/zero/1.0/>.
+//
+// SPDX-License-Identifier: CC-PDDC
+// SPDX-FileCopyrightText: None
 ///
 
 #ifndef TL_EXPECTED_HPP