diff --git a/sys/timex/timex.c b/sys/timex/timex.c
index 33da161e51..0878b54695 100644
--- a/sys/timex/timex.c
+++ b/sys/timex/timex.c
@@ -1,3 +1,22 @@
+/**
+ * Timex implementation
+ *
+ * Copyright (C) 2009, 2010, 2013, 2014 Freie Universitaet Berlin (FUB).
+ * Copyright (C) 2013, INRIA.
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser General
+ * Public License. See the file LICENSE in the top level directory for more
+ * details.
+ */
+ 
+/**
+ * @file
+ * @author Kaspar Schleiser <kaspar@schleiser.de>
+ * @author Oliver Hahm <oliver.hahm@inria.fr>
+ * @author Christian Mehlis <mehlis@inf.fu-berlin.de>
+ *
+ */
+
 #include <stdio.h>
 #include <inttypes.h>