diff --git a/Documentation/conf.py b/Documentation/conf.py
index bffd1d8f..78602c85 100644
--- a/Documentation/conf.py
+++ b/Documentation/conf.py
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: CC-BY-SA-4.0
 # -*- coding: utf-8 -*-
 #
 # Configuration file for the Sphinx documentation builder.
diff --git a/Documentation/theme/footer.html b/Documentation/theme/footer.html
index e63e9fb3..12939e8b 100644
--- a/Documentation/theme/footer.html
+++ b/Documentation/theme/footer.html
@@ -1,3 +1,6 @@
+{#
+SPDX-License-Identifier: CC-BY-SA-4.0
+#}
 <footer>
   <div id="signature">
     {%- if show_copyright %}
diff --git a/Documentation/theme/layout.html b/Documentation/theme/layout.html
index 139c39c7..fcc6d221 100644
--- a/Documentation/theme/layout.html
+++ b/Documentation/theme/layout.html
@@ -1,3 +1,6 @@
+{#
+SPDX-License-Identifier: CC-BY-SA-4.0
+#}
 {# TEMPLATE VAR SETTINGS #}
 {%- set url_root = pathto('', 1) %}
 {%- if url_root == '#' %}{% set url_root = '' %}{% endif %}
diff --git a/Documentation/theme/search.html b/Documentation/theme/search.html
index 14d59395..00c2af93 100644
--- a/Documentation/theme/search.html
+++ b/Documentation/theme/search.html
@@ -1,3 +1,6 @@
+{#
+SPDX-License-Identifier: CC-BY-SA-4.0
+#}
 {#
     basic/search.html
     ~~~~~~~~~~~~~~~~~
diff --git a/Documentation/theme/static/css/theme.css b/Documentation/theme/static/css/theme.css
index a4934ede..d4274ea6 100644
--- a/Documentation/theme/static/css/theme.css
+++ b/Documentation/theme/static/css/theme.css
@@ -1,3 +1,5 @@
+/* SPDX-License-Identifier: CC-BY-SA-4.0 */
+
 html {
 	background-image: linear-gradient(to bottom right, #4895e1, #56c3ae);
 	background-size: cover;
diff --git a/Documentation/theme/theme.conf b/Documentation/theme/theme.conf
index ba25a192..f2ab39c3 100644
--- a/Documentation/theme/theme.conf
+++ b/Documentation/theme/theme.conf
@@ -1,3 +1,5 @@
+# SPDX-License-Identifier: CC-BY-SA-4.0
+
 [theme]
 inherit = basic
 stylesheet = css/theme.css