diff --git a/MatrixConnection.php b/MatrixConnection.php
index aa63a3c..5401df1 100644
--- a/MatrixConnection.php
+++ b/MatrixConnection.php
@@ -1,4 +1,18 @@
 <?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 class MatrixConnection
 {
 	private $hs;
diff --git a/cron.php b/cron.php
index 473a3cd..1ef0ec0 100644
--- a/cron.php
+++ b/cron.php
@@ -1,4 +1,18 @@
 <?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 require_once("config.php");
 require_once("mail_templates.php");
 require_once("database.php");
diff --git a/database.php b/database.php
index 18f00c6..558ed7f 100644
--- a/database.php
+++ b/database.php
@@ -1,4 +1,18 @@
 <?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 require_once("config.php");
 if (!isset($config["databaseURI"])) {
 	throw new Exception ("malformed configuration: databaseURI not defined");
diff --git a/internal/directory_search.php b/internal/directory_search.php
index fe2b5e1..2d6f28e 100644
--- a/internal/directory_search.php
+++ b/internal/directory_search.php
@@ -1,4 +1,18 @@
 <?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 require_once("../database.php");
 $response=[
     "limited" => false,
diff --git a/internal/identity_bulk.php b/internal/identity_bulk.php
index 3768a70..dcae3a8 100644
--- a/internal/identity_bulk.php
+++ b/internal/identity_bulk.php
@@ -1,4 +1,18 @@
 <?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 require_once("../database.php");
 $response = [
     "lookup" => []
diff --git a/internal/identity_single.php b/internal/identity_single.php
index 404f019..9010707 100644
--- a/internal/identity_single.php
+++ b/internal/identity_single.php
@@ -1,4 +1,18 @@
 <?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 require_once("../database.php");
 $response = new stdClass;
 try {
diff --git a/internal/login.php b/internal/login.php
index e63bd08..9bd92e2 100644
--- a/internal/login.php
+++ b/internal/login.php
@@ -1,4 +1,18 @@
 <?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 $response = [
     "auth" => [
         "success" => false,
diff --git a/lang/lang.de-de.php b/lang/lang.de-de.php
index 84dafb0..cd2c310 100644
--- a/lang/lang.de-de.php
+++ b/lang/lang.de-de.php
@@ -1,4 +1,18 @@
 <?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 $language = array(
     "NO_CONFIGURATION" => "Es konnte keine Konfiguration gefunden werden.",
     "UNKNOWN_SESSION" => "Sitzungstoken nicht vorhanden oder ungültig.",
diff --git a/language.php b/language.php
index 5a1c960..e7ef71c 100644
--- a/language.php
+++ b/language.php
@@ -1,4 +1,18 @@
 <?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 $lang = "de-de";
 if(isset($_GET['lang'])){
 	$lang = filter_var($_GET['lang'], FILTER_SANITIZE_STRING);
diff --git a/mail_templates.php b/mail_templates.php
index c6a3b22..550a7cc 100644
--- a/mail_templates.php
+++ b/mail_templates.php
@@ -1,5 +1,18 @@
 <?php
-
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 function send_mail($receiver, $subject, $body) {
 	include("config.php");
 	$headers = "From: " . $config["register_email"] . "\r\n"
diff --git a/public/index.php b/public/index.php
index 79dce94..735a24e 100644
--- a/public/index.php
+++ b/public/index.php
@@ -1,6 +1,18 @@
-<html>
-	<head>
-<?php
+<html><head><?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 require_once "../language.php";
 if (!file_exists("../config.php")) {
 	print($language["NO_CONFIGURATION"]);
diff --git a/public/verify.php b/public/verify.php
index e19a578..b426dc8 100644
--- a/public/verify.php
+++ b/public/verify.php
@@ -1,6 +1,18 @@
-<html>
-	<head>
-<?php
+<html><head><?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 require_once "../language.php";
 if (!file_exists("../config.php")) {
 	print($language["NO_CONFIGURATION"]);
diff --git a/public/verify_admin.php b/public/verify_admin.php
index 6b397d0..00ecbd5 100644
--- a/public/verify_admin.php
+++ b/public/verify_admin.php
@@ -1,6 +1,18 @@
-<html>
-<head>
-<?php
+<html><head><?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 require_once "../language.php";
 if (!file_exists("../config.php")) {
 	print($language["NO_CONFIGURATION"]);