diff --git a/runtime/pom.xml b/runtime/pom.xml
index 9ab170a..2671ea0 100644
--- a/runtime/pom.xml
+++ b/runtime/pom.xml
@@ -1,4 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
+
+<!--
+SPDX-FileCopyrightText: © 2021 Matthias Andreas Benkard <code@mail.matthias.benkard.de>
+
+SPDX-License-Identifier: LGPL-3.0-or-later
+-->
+
 <project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
 
diff --git a/runtime/src/main/java/eu/mulk/quarkus/googlecloud/jsonlogging/runtime/GoogleCloudJsonLoggingRecorder.java b/runtime/src/main/java/eu/mulk/quarkus/googlecloud/jsonlogging/runtime/GoogleCloudJsonLoggingRecorder.java
index 84d9112..7366a55 100644
--- a/runtime/src/main/java/eu/mulk/quarkus/googlecloud/jsonlogging/runtime/GoogleCloudJsonLoggingRecorder.java
+++ b/runtime/src/main/java/eu/mulk/quarkus/googlecloud/jsonlogging/runtime/GoogleCloudJsonLoggingRecorder.java
@@ -1,3 +1,7 @@
+// SPDX-FileCopyrightText: © 2021 Matthias Andreas Benkard <code@mail.matthias.benkard.de>
+//
+// SPDX-License-Identifier: LGPL-3.0-or-later
+
 package eu.mulk.quarkus.googlecloud.jsonlogging.runtime;
 
 import eu.mulk.quarkus.googlecloud.jsonlogging.Formatter;
diff --git a/runtime/src/main/java/eu/mulk/quarkus/googlecloud/jsonlogging/runtime/package-info.java b/runtime/src/main/java/eu/mulk/quarkus/googlecloud/jsonlogging/runtime/package-info.java
index 2fa7499..3d1af08 100644
--- a/runtime/src/main/java/eu/mulk/quarkus/googlecloud/jsonlogging/runtime/package-info.java
+++ b/runtime/src/main/java/eu/mulk/quarkus/googlecloud/jsonlogging/runtime/package-info.java
@@ -1,3 +1,7 @@
+// SPDX-FileCopyrightText: © 2021 Matthias Andreas Benkard <code@mail.matthias.benkard.de>
+//
+// SPDX-License-Identifier: LGPL-3.0-or-later
+
 /**
  * Provides structured logging to standard output according to the Google Cloud Logging
  * specification.
diff --git a/runtime/src/main/resources/META-INF/quarkus-extension.yaml b/runtime/src/main/resources/META-INF/quarkus-extension.yaml
index 7aa7a2a..f015557 100644
--- a/runtime/src/main/resources/META-INF/quarkus-extension.yaml
+++ b/runtime/src/main/resources/META-INF/quarkus-extension.yaml
@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: © 2021 Matthias Andreas Benkard <code@mail.matthias.benkard.de>
+#
+# SPDX-License-Identifier: LGPL-3.0-or-later
+
 name: Google Cloud JSON Logging
 description: Logs to standard output in Google-Cloud-compatible JSON format.
 metadata: