diff --git a/documentation/dev-manual/dev-manual-common-tasks.xml b/documentation/dev-manual/dev-manual-common-tasks.xml
index 605d1ad7ea..d29fe6262d 100644
--- a/documentation/dev-manual/dev-manual-common-tasks.xml
+++ b/documentation/dev-manual/dev-manual-common-tasks.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='extendpoky'>
 
diff --git a/documentation/dev-manual/dev-manual-customization.xsl b/documentation/dev-manual/dev-manual-customization.xsl
index 523ea3c5ed..6b16bcabf9 100644
--- a/documentation/dev-manual/dev-manual-customization.xsl
+++ b/documentation/dev-manual/dev-manual-customization.xsl
@@ -1,4 +1,6 @@
 <?xml version='1.0'?>
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
+
 <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns="http://www.w3.org/1999/xhtml" xmlns:fo="http://www.w3.org/1999/XSL/Format" version="1.0">
 
   <xsl:import href="http://downloads.yoctoproject.org/mirror/docbook-mirror/docbook-xsl-1.76.1/xhtml/docbook.xsl" />
diff --git a/documentation/dev-manual/dev-manual-intro.xml b/documentation/dev-manual/dev-manual-intro.xml
index 3a34094b8c..38de5e4f53 100644
--- a/documentation/dev-manual/dev-manual-intro.xml
+++ b/documentation/dev-manual/dev-manual-intro.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='dev-manual-intro'>
 
diff --git a/documentation/dev-manual/dev-manual-qemu.xml b/documentation/dev-manual/dev-manual-qemu.xml
index 5ccc0dfe83..46fe67bab0 100644
--- a/documentation/dev-manual/dev-manual-qemu.xml
+++ b/documentation/dev-manual/dev-manual-qemu.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='dev-manual-qemu'>
 
diff --git a/documentation/dev-manual/dev-manual-start.xml b/documentation/dev-manual/dev-manual-start.xml
index 8cb5631f0d..9ff9ac4c8f 100644
--- a/documentation/dev-manual/dev-manual-start.xml
+++ b/documentation/dev-manual/dev-manual-start.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='dev-manual-start'>
 
diff --git a/documentation/dev-manual/dev-manual.xml b/documentation/dev-manual/dev-manual.xml
index 6f86454ede..66439930e4 100755
--- a/documentation/dev-manual/dev-manual.xml
+++ b/documentation/dev-manual/dev-manual.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <book id='dev-manual' lang='en'
       xmlns:xi="http://www.w3.org/2003/XInclude"
diff --git a/documentation/dev-manual/dev-style.css b/documentation/dev-manual/dev-style.css
index 6d0aa8e9fa..331c7c54d4 100644
--- a/documentation/dev-manual/dev-style.css
+++ b/documentation/dev-manual/dev-style.css
@@ -1,4 +1,7 @@
 /*
+
+   SPDX-License-Identifier: CC-BY-2.0-UK
+
    Generic XHTML / DocBook XHTML CSS Stylesheet.
 
    Browser wrangling and typographic design by