This is Ubuntu GNU's GnuPG keyrings of archive keys.

This package was originally put together by Michael Vogt
<michael.vogt@canonical.com> 

The keys in the keyrings don't fall under any copyright.  Everything
else in the package is covered by the GNU GPL.

Ubuntu support files Copyright (C) 2004 Michael Vogt <michael.vogt@canonical.com> based on the debian-keyring package maintained by James Troup 

Ubuntu support files for ubuntu-keyring are free software; you can
redistribute them and/or modify them under the terms of the GNU
General Public License as published by the Free Software Foundation;
either version 2, or (at your option) any later version.

Ubuntu support files for ubuntu-keyring are distributed in the hope
that they 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 with
your Ubuntu system, in /usr/share/common-licenses/GPL, or with the
Ubuntu GNU ubuntu-keyring source package as the file COPYING.  If not,
write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
Floor, Boston, MA 02110-1301 USA.