diff --git a/build/license.php b/build/license.php
new file mode 100644
index 0000000000..bd3bce15a4
--- /dev/null
+++ b/build/license.php
@@ -0,0 +1,166 @@
+<?php
+/**
+ * @author Thomas Müller
+ *
+ * @copyright Copyright (c) 2015, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+class Licenses
+{
+	protected $paths = array();
+
+	public function __construct() {
+		$this->licenseText = <<<EOD
+/**
+@AUTHORS@
+ *
+ * @copyright Copyright (c) @YEAR@, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+EOD;
+		$this->licenseText = str_replace('@YEAR@', date("Y"), $this->licenseText);
+	}
+
+	function exec($folder) {
+
+		if (is_array($folder)) {
+			foreach($folder as $f) {
+				$this->exec($f);
+			}
+			return;
+		}
+
+		if (is_file($folder)) {
+			$this->handleFile($folder);
+			return;
+		}
+
+		$excludes = array_map(function($item) use ($folder) {
+			return $folder . '/' . $item;
+		}, ['vendor', '3rdparty', '.git', 'l10n', 'templates']);
+
+		$iterator = new RecursiveDirectoryIterator($folder, RecursiveDirectoryIterator::SKIP_DOTS);
+		$iterator = new RecursiveCallbackFilterIterator($iterator, function($item) use ($folder, $excludes){
+			/** @var SplFileInfo $item */
+			foreach($excludes as $exclude) {
+				if (substr($item->getPath(), 0, strlen($exclude)) === $exclude) {
+					return false;
+				}
+			}
+			return true;
+		});
+		$iterator = new RecursiveIteratorIterator($iterator);
+		$iterator = new RegexIterator($iterator, '/^.+\.php$/i');
+
+		foreach ($iterator as $file) {
+			/** @var SplFileInfo $file */
+			$this->handleFile($file);
+		}
+
+	}
+
+	function handleFile($path) {
+		$source = file_get_contents($path);
+		$source = $this->eatOldLicense($source);
+		$authors = $this->getAuthors($path);
+		$license = str_replace('@AUTHORS@', $authors, $this->licenseText);
+
+		$source = "<?php" . PHP_EOL . $license . PHP_EOL . $source;
+		file_put_contents($path,$source);
+		echo "License updated: $path\n";
+	}
+
+	private function eatOldLicense($source) {
+		$lines = explode(PHP_EOL, $source);
+		while(!empty($lines)) {
+			$line = $lines[0];
+			if (strpos($line, '<?php') !== false) {
+				array_shift($lines);
+				continue;
+			}
+			if (strpos($line, '/**') !== false) {
+				array_shift($lines);
+				continue;
+			}
+			if (strpos($line, '*') !== false) {
+				array_shift($lines);
+				continue;
+			}
+			if (strpos($line, '*/') !== false) {
+				array_shift($lines);
+				continue;
+			}
+			if (trim($line) === '') {
+				array_shift($lines);
+				continue;
+			}
+			break;
+		}
+
+		return implode(PHP_EOL, $lines);
+	}
+
+	private function getAuthors($file) {
+		$out = shell_exec("git blame --line-porcelain $file | sed -n 's/^author //p;s/^author-mail //p' | sed 'N;s/\\n/ /' | sort | uniq");
+		$authors = explode(PHP_EOL, $out);
+
+		$authors = array_filter($authors, function($author) {
+			return !in_array($author, ['', 'Not Committed Yet', 'Jenkins for ownCloud <owncloud-bot@tmit.eu>']);
+		});
+		$authors = array_map(function($author){
+			return " * @author $author";
+		}, $authors);
+		return implode(PHP_EOL, $authors);
+	}
+}
+
+$licenses = new Licenses;
+$licenses->exec([
+	'../apps/files',
+	'../apps/files_encryption',
+	'../apps/files_external',
+	'../apps/files_sharing',
+	'../apps/files_trashbin',
+	'../apps/files_versions',
+	'../apps/provisioning_api',
+	'../apps/user_ldap',
+	'../apps/user_webdavauth',
+	'../core',
+	'../lib',
+	'../ocs',
+	'../settings',
+	'../console.php',
+	'../cron.php',
+	'../index.php',
+	'../public.php',
+	'../remote.php',
+	'../status.php',
+	'../version.php',
+]);
+