Mozilla Public License

The Mozilla Public License (MPL) is a free and open source software license. Version 1.0 was developed by Mitchell Baker when she worked as a lawyer at Netscape Communications Corporation and version 1.1 at the Mozilla Foundation. The MPL is characterized as a hybridization of the modified BSD license and GNU General Public License.

The MPL is the license for the Mozilla Application Suite, Mozilla Firefox, Mozilla Thunderbird and other Mozilla software. The MPL has been adapted by others as a license for their software, most notably Sun Microsystems, as the Common Development and Distribution License for OpenSolaris, the open source version of the Solaris 10 operating system, and by Adobe, as the license for its Flex product line.

Terms

The license is regarded as a weak copyleft. Specifically, source code copied or changed under the MPL must stay under the MPL.

The MPL was approved both as an Open Source software license by the Open Source Initiative and as a Free Software license by the Free Software Foundation.

Compatibility with other licenses

Unlike strong copyleft licenses, the code under the MPL may be combined with proprietary files in one program ("Larger Work"). For example, Netscape 6 and later releases were proprietary versions of the Mozilla Application Suite, by adding the proprietary AIM and other parts. The MPL treats the source code file as the boundary between MPL code and proprietary parts, meaning that a certain source file (e.g., C++, JavaScript or XUL file) is either fully MPL or fully proprietary. The GPL, in contrast, uses the process boundary of the executable as the license boundary (for details, see the GPL article).

Compatibility with GPL

The Free Software Foundation (FSF) considers the license a free software license, but "not a strong copyleft" one. However, "unlike the X11 license" the license has "some complex restrictions" making it incompatible with the GNU GPL. They urge people not to use the license because of this incompatibility unless the provision in section 13 of the MPL is exercised to provide the work under either the GPL or any other GPL-compatible license.

For these reasons, the Mozilla Suite and Firefox have been relicensed under multiple licenses, including the MPL, GPL and LGPL.

MPL-based licenses

* Common Development and Distribution License
* Sun Public License
* gSOAP Public License
* AROS Public License
* SugarCRM Public License
* Common Public Attribution License
* Erlang Public License
* Yahoo! Public License

Eclipse Public License

The Eclipse Public License (EPL) is an open source software license used by the Eclipse Foundation for its software. It replaces the Common Public License (CPL) and removes certain terms relating to patent litigation.

The Eclipse Public License is designed to be a business friendly free software license, and features weaker copyleft provisions than contemporary licenses such as the GNU General Public License (GPL). The receiver of EPL-licensed programs can use, modify, copy and distribute the work and modified versions, in some cases being obligated to release their own changes.

The EPL is approved by the Open Source Initiative (OSI) and the Free Software Foundation (FSF)

MIT License

The MIT License is a free software license originating at the Massachusetts Institute of Technology (MIT), used by the MIT X Consortium.

It is a permissive license, meaning that it permits reuse within proprietary software on the condition that the license is distributed with that software. The license is also GPL-compatible, meaning that the GPL permits combination and redistribution with software that uses the MIT License.

According to the Free Software Foundation, the MIT License is more accurately called the X11 license, since MIT has used many licenses for software and the license was first drafted for the X Window System.

Software packages that use the MIT License include Expat, PuTTY, the Mono development platform class libraries, Ruby on Rails, Lua 5.0 onwards and the X Window System, for which the license was written.

Some software packages dual license their products under the MIT License, such as the JavaScript library jQuery, which is licensed under both the MIT and GNU General Public License licenses.

The license is as follows:

Copyright (c)  

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS 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. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.