Without much fanfare, MS changed the license for their Dynamic Language Runtime to Apache 2.0, as well as the IronPython and IronRuby language implementations which require it.

Conjectures for this change range from compatibility with GPLv3 to purely marketing, and from a broadening appreciation for open source to yet another attempt to crush it.

Python License (CNRI Python License)

CNRI OPEN SOURCE LICENSE AGREEMENT

IMPORTANT: PLEASE READ THE FOLLOWING AGREEMENT CAREFULLY.

BY CLICKING ON "ACCEPT" WHERE INDICATED BELOW, OR BY COPYING, INSTALLING OR
OTHERWISE USING PYTHON 1.6, beta 1 SOFTWARE, YOU ARE DEEMED TO HAVE AGREED TO
THE TERMS AND CONDITIONS OF THIS LICENSE AGREEMENT.

SUN PUBLIC LICENSE Version 1.0

1. Definitions.

1.0.1. "Commercial Use" means distribution or otherwise making the
Covered Code available to a third party.

1.1. "Contributor" means each entity that creates or contributes to
the creation of Modifications.

Artistic License 2.0

Copyright (c) 2000-2006, The Perl Foundation.

Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

The BSD License

The following is a BSD license template. To generate your own license, change the values of OWNER, ORGANIZATION and YEAR from their original values as given here, and substitute your own. Also, you may optionally omit clause 3 and still be OSD conformant.

PostgreSQL is released under the BSD license.

PostgreSQL Database Management System
(formerly known as Postgres, then as Postgres95)

Portions Copyright (c) 1996-2009, The PostgreSQL Global Development Group

Portions Copyright (c) 1994, The Regents of the University of California

Permission to use, copy, modify, and distribute this software and its documentation for any purpose, without fee, and without a written agreement is hereby granted, provided that the above copyright notice and this paragraph and the following two paragraphs appear in all copies.

Apache License
Version 2.0, January 2004
http://www.apache.org/licenses/

TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION

1. Definitions.

"License" shall mean the terms and conditions for use, reproduction, and distribution as defined by Sections 1 through 9 of this document.

"Licensor" shall mean the copyright owner or entity authorized by the copyright owner that is granting the License.

Ruby is copyrighted free software by Yukihiro Matsumoto .
You can redistribute it and/or modify it under either the terms of the GPL
(see COPYING.txt file), or the conditions below:

1. You may make and give away verbatim copies of the source form of the
software without restriction, provided that you duplicate all of the
original copyright notices and associated disclaimers.

2. You may modify your copy of the software in any way, provided that
you do at least ONE of the following: