License below is copied from <http://www.unicode.org/copyright.html>,
last updated 7 July 2004, and claims to apply to all Unicode versions.
According to a post on emacs-devel,
<http://lists.gnu.org/archive/html/emacs-devel/2004-04/msg00036.html>,
RMS believe it is a free license:
This is a free license, and even compatible with the GPL (if
that ever matters). Yes, we can use it now.
EXHIBIT 1
UNICODE, INC. LICENSE AGREEMENT - DATA FILES AND SOFTWARE
Unicode Data Files include all data files under the directories
http://www.unicode.org/Public/ and
http://www.unicode.org/reports/. Unicode Software includes any source
code under the directories http://www.unicode.org/Public/ and
http://www.unicode.org/reports/.
NOTICE TO USER: Carefully read the following legal agreement. BY
DOWNLOADING, INSTALLING, COPYING OR OTHERWISE USING UNICODE INC.'S
DATA FILES ("DATA FILES"), AND/OR SOFTWARE ("SOFTWARE"), YOU
UNEQUIVOCALLY ACCEPT, AND AGREE TO BE BOUND BY, ALL OF THE TERMS AND
CONDITIONS OF THIS AGREEMENT. IF YOU DO NOT AGREE, DO NOT DOWNLOAD,
INSTALL, COPY, DISTRIBUTE OR USE THE DATA FILES OR SOFTWARE.
COPYRIGHT AND PERMISSION NOTICE
Copyright © 1991-2004 Unicode, Inc. All rights reserved. Distributed
under the Terms of Use in http://www.unicode.org/copyright.html.
Permission is hereby granted, free of charge, to any person obtaining
a copy of the Unicode data files and associated documentation (the
"Data Files") or Unicode software and associated documentation (the
"Software") to deal in the Data Files or Software without restriction,
including without limitation the rights to use, copy, modify, merge,
publish, distribute, and/or sell copies of the Data Files or Software,
and to permit persons to whom the Data Files or Software are furnished
to do so, provided that (a) the above copyright notice(s) and this
permission notice appear in all copies of the Data Files or Software,
(b) both the above copyright notice(s) and this permission notice
appear in associated documentation, and (c) there is clear notice in
each modified Data File or in the Software as well as in the
documentation associated with the Data File(s) or Software that the
data or software has been modified.
THE DATA FILES AND SOFTWARE ARE PROVIDED "AS IS", WITHOUT WARRANTY OF
ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT
HOLDER OR HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR
ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THE DATA FILES OR
SOFTWARE.
Except as contained in this notice, the name of a copyright holder
shall not be used in advertising or otherwise to promote the sale, use
or other dealings in these Data Files or Software without prior
written authorization of the copyright holder.