Open source license

An open source license is a copyright license for computer software that makes the source code available under terms that allow for modification and redistribution without having to pay the original author. Such licenses may have additional restrictions such as a requirement to preserve the name of the authors and the copyright statement within the code. One popular (and sometimes considered normative) set of open source software licenses are those approved by the Open Source Initiative (OSI) based on their Open Source Definition (OSD).

Contents 1 Comparisons 2 OSI approved licenses 2.1 Licenses that are popular and widely used or with strong communities (11) 2.2 Special purpose licenses (3) 2.3 Other/Miscellaneous licenses (7) 2.4 Licenses that are redundant with more popular licenses (8) 2.5 Non-reusable licenses (25) 2.6 Superseded licenses (4) 2.7 Licenses that have been voluntarily retired (4) 2.8 Not categorized 3 Non-OSI source licenses 4 See also 5 References 6 External links 6.1 Wikibooks

Comparisons

The Free Software Foundation has related but distinct criteria for evaluating whether or not a license qualifies a program as free software. All licenses qualified as free software are also considered open source licenses. Likewise, the Debian project has its own criteria, the Debian Free Software Guidelines, on which the Open Source Definition is based.

There are also shared source licenses which have some similarities with open source, such as the Microsoft Reference License (MS-RL), but are not compatible with the Open Source Definition.

OSI approved licenses

Software in the public domain (that is, with all copyright renounced), meets those criteria as long as all source code is made available, and is therefore recognized by the OSI and entitled to use their service mark. In addition, OSI has approved the following licenses as of 2007^[update]:

The categories were created by a license proliferation committee in 2006 to lessen or remove issues caused by license proliferation^[1].

Licenses that are popular and widely used or with strong communities (11)

• Affero General Public License (AGPL)
• Apache Software License 2.0
• new BSD License
• Common Development and Distribution License
• Common Public License 1.0
• Eclipse Public License
• GNU General Public License (GPL)
• GNU Lesser General Public License (LGPL)
• ISC license
• MIT License
• Mozilla Public License (MPL) 1.1

Special purpose licenses (3)

• Educational Community License
• NASA Open Source Agreement
• Open Group Test Suite License

Other/Miscellaneous licenses (7)

• Adaptive Public License (APL)
• Artistic License
• Microsoft Public License
• Microsoft Reciprocal License
• Open Software License
• Q Public License (QPL)
• zlib-libpng license

Licenses that are redundant with more popular licenses (8)

• Academic Free License
• Attribution Assurance Licenses
• Eiffel Forum License 2
• Fair License
• Historical Permission Notice and Disclaimer
• Lucent Public License 1.02
• University of Illinois/NCSA Open Source License
• X.Net License

Non-reusable licenses (25)

• Apple Public Source License
• Computer Associates Trusted Open Source License
• CUA Office Public License
• Entessa Public License
• EU DataGrid Software License
• Frameworx License
• IBM Public License
• Motosoto License
• Naumen Public License
• NetHack General Public License
• Nokia Open Source License
• OCLC Research Public License 2.0
• PHP License
• Python License (CNRI Python License)
• Python Software Foundation License
• RealNetworks Public Source License
• Reciprocal Public License
• Ricoh Source Code Public License
• Sleepycat License
• Sun Public License (SPL)
• Sybase Open Watcom Public License
• Vovida Software License v. 1.0
• W3C License
• wxWindows Library License
• Zope Public License

Superseded licenses (4)

• Apache Software License 1.1
• Eiffel Forum License 1
• Lucent Public License Plan9
• Mozilla Public License (MPL) 1.0

Licenses that have been voluntarily retired (4)

• MITRE Collaborative Virtual Workspace License (CVW License)
• Intel Open Source License
• Jabber Open Source License
• Sun Industry Standards Source License (SISSL)

Not categorized

• Common Public Attribution License

Non-OSI source licenses

Licenses that are source-available but not OSI-Certified include:

• HESSLA
• Lemur License Agreement
• MAME (source available, but not free software because it forbids commercial use and redistribution)
• PGP
• Ruby License (Ruby is open-source, since it is GPL dual-licensed)

See also

• Comparison of free software licences
• Beerware
• Dual licensing
• Free software license
• Free Software Foundation
• Jacobsen v. Katzer -- U.S. ruling upholding the enforceability of open source licenses
• Open Source Initiative
• Software license

References

External links

• The Open Source Initiative
• Open Source Licensing — a review and discussion of Lawrence Rosen's book Open Source Licensing: Software Freedom and Intellectual Property Law (ISBN 0-13-148787-6) on slashdot
• Open Source License Quick Reference Chart — a chart comparing various aspects of Open Source licenses, with the option to select your bias. Based on Zooko's document, Open Source Reference for Choosing a Free Software License.
• Understanding Open Source Software - by Red Hat's Mark Webbink, Esq. — an excellent overview of copyright and open source.
• Discussion "Open Source/Free Software v Commercial Licence Software"
• EU report in favor of adopting open source software
• Shared Source Licenses

Wikibooks

• Free/Open Source Software:Localization