diff --git a/ipv6expand.pl b/ipv6expand.pl
index 16af512..24ff0c5 100755
--- a/ipv6expand.pl
+++ b/ipv6expand.pl
@@ -1,4 +1,21 @@
 #!/usr/bin/env perl
+#  Copyright 2016 Mikael Nordin <mik@elnord.in>
+#  
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation; either version 3 of the License, or
+#  (at your option) any later version.
+#  
+#  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 General Public License for more details.
+#  
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software
+#  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+#  MA 02110-1301, USA.
+
 
 use strict;
 use warnings;