software relicensing

Sometimes open-source software projects get stuck in a license incompatibility situation. Often the only feasible way to resolve this situation is re-licensing of all participating software parts. For successful relicensing the agreement of all involved copyright holders, typically the developers, to a changed license is required. While in the free and open-source domain achieving 100% coverage of all authors is often impossible due to the many contributors involved, often it is assumed that a great majority is sufficient. For instance, Mozilla assumed an author coverage of 95% to be sufficient.{{cite web|url=http://blogs.fsfe.org/ciaran/?p=58 |title=(About GPLv3) Can the Linux Kernel Relicense? |first=Ciaran |last=O’Riordan |date=2006-10-06 |access-date=2015-05-28 |publisher=fsfe.org |quote="Someone who works with many lawyers on free software copyright issues later told me that it is not necessary to get permission from 100% of the copyright holders. It would suffice if there was permission from the copyright holders of 95% of the source code and no objections from the holders of the other 5%. This, I’m told, is how Mozilla was able to relicense to the GPL in 2003 despite years of community contributions."}} Others in the free and open-source software (FOSS) domain, such as Eric S. Raymond, came to different conclusions regarding the requirements for relicensing of a whole code base.[http://www.catb.org/~esr/Licensing-HOWTO.html Licensing HOWTO] by Eric Steven Raymond&Catherine Olanich Raymond "Changing an existing license [...]You can change the license on a piece of code under any of the following conditions: If you are the sole copyright holder[...]If you are the sole registered copyright holder[...] If you obtain the consent of all other copyright holders[...]If no other copyright holder could be harmed by the change" (accessed on 2015-11-21)

An early example of an open-source project that did successfully re-license for license compatibility reasons is the Mozilla project and their Firefox browser. The source code of Netscape's Communicator 4.0 browser was originally released in 1998 under the Netscape Public License/Mozilla Public License[https://website-archive.mozilla.org/www.mozilla.org/mpl/MPL/NPL/1.0/FAQ.html Netscape Public License FAQ] on mozilla.org but was criticised by the FSF and OSI for being incompatible.{{cite web|title=Licenses by Name - Open Source Initiative |publisher=Open Source Initiative |url=http://opensource.org/licenses/alphabetical |access-date=2014-08-27}}[https://www.gnu.org/philosophy/netscape-npl.html On the Netscape Public License] by Richard Stallman on GNU.org Around 2001 Time Warner, exercising its rights under the Netscape Public License, and at the request of the Mozilla Foundation, relicensed{{cite web|url=https://www.mozilla.org/MPL/relicensing-faq.html |archive-url=https://web.archive.org/web/20100513062601/http://www-archive.mozilla.org/MPL/relicensing-faq.html |archive-date=2010-05-13 |title=Mozilla Relicensing FAQ Version 1.1 |publisher=mozilla.org |quote=Some time ago mozilla.org announced its intent to seek relicensing of Mozilla code under a new licensing scheme that would address perceived incompatibilities of the Mozilla Public License (MPL) with the GNU General Public License (GPL) and GNU Lesser General Public License (LGPL).}} all code in Mozilla that was under the Netscape Public License (including code by other contributors) to an MPL 1.1/GPL 2.0/LGPL 2.1 tri-license, thus achieving GPL-compatibility.[http://blog.gerv.net/2006/03/relicensing_complete/ Relicensing Complete] on gerv.net by Gervase Markham (March 31, 2006)

The Vorbis library was originally licensed as LGPL, but in 2001 the license was changed to the BSD license with endorsement of Richard Stallman to encourage adoption.[http://lists.xiph.org/pipermail/vorbis/2001-February/001758.html February 2001] on xiph.org "With the Beta 4 release, the Ogg Vorbis libraries have moved to the BSD license. The change from LGPL to BSD was made to enable the use of Ogg Vorbis in all forms of software and hardware. Jack Moffitt says, "We are changing the license in response to feedback from many parties. It has become clear to us that adoption of Ogg Vorbis will be accelerated even further by the use of a less restrictive license that is friendlier toward proprietary software and hardware systems. We want everyone to be able to use Ogg Vorbis.""[https://lwn.net/2001/0301/a/rms-ov-license.php3 RMS on license change] on lwn.net

The VLC project also has a complicated license history due to license compatibility: in 2007 it decided for license compatibility reasons to not upgrade to the just released GPLv3.{{cite web|url=http://www.videolan.org/press/2007-1.html |title=VLC media player to remain under GNU GPL version 2 |quote=In 2001, VLC was released under the OSI-approved GNU General Public version 2, with the commonly-offered option to use "any later version" thereof (though there was not any such later version at the time). Following the release by the Free Software Foundation (FSF) of the new version 3 of its GNU General Public License (GPL) on the 29th of June 2007, contributors to the VLC media player, and other software projects hosted at videolan.org, debated the possibility of updating the licensing terms for future version of the VLC media player and other hosted projects, to version 3 of the GPL. [...] There is strong concern that these new additional requirements might not match the industrial and economic reality of our time, especially in the market of consumer electronics. It is our belief that changing our licensing terms to GPL version 3 would currently not be in the best interest of our community as a whole. Consequently, we plan to keep distributing future versions of VLC media player under the terms of the GPL version 2. [...]we will continue to distribute the VLC media player source code under GPL "version 2 or any later version" until further notice. |publisher=videolan.org|access-date=2015-11-21|first=Rémi |last=Denis-Courmont }} After VLC was removed from Apple App Store at the beginning of 2011, in October 2011 the VLC project re-licensed the VLC library part from the GPLv2 to the LGPLv2 to achieve better compatibility.{{cite web|title=Changing the VLC engine license to LGPL|url=http://www.videolan.org/press/lgpl.html |access-date=23 October 2011}}{{cite web|last=Vaughan-Nichols|first=Steven|title=No GPL Apps for Apple's App Store |url=http://www.zdnet.com/blog/open-source/no-gpl-apps-for-apples-app-store/8046|archive-url=https://web.archive.org/web/20110109000122/http://www.zdnet.com/blog/open-source/no-gpl-apps-for-apples-app-store/8046|url-status=dead|archive-date=January 9, 2011|access-date=23 October 2011 |publisher=zdnet.com}} In July 2013 the VLC application could then be resubmitted to the iOS App Store relicensed under the Mozilla Public License.[https://arstechnica.com/apple/2013/07/vlc-media-player-returns-to-the-ios-app-store-after-30-month-hiatus/ VLC under Mozilla public relaunched.] on Ars Technica (Accessed 10/10/2013)

7-Zip's LZMA SDK, originally dual-licensed under both the GNU LGPL and Common Public License,{{cite web | url = http://sourceforge.net/projects/sevenzip/files/LZMA%20SDK/4.23/ | title = Browse /LZMA SDK/4.23 | access-date = 2014-02-12 | publisher = SourceForge}} with an additional special exception for linked binaries, was placed by Igor Pavlov in the public domain on December 2, 2008.{{cite web

| url=http://7-zip.org/sdk.html

| title=LZMA SDK (Software Development Kit)

| year=2013

| first=Igor

| last=Pavlov

| author-link=Igor Pavlov (programmer)

| access-date=2013-06-16}}

The GNU TLS project adopted the LGPLv3 license in 2011 but in 2013 relicensed their code back to LGPLv2.1 due to serious license compatibility problems.{{cite web|url=http://nmav.gnutls.org/2013/03/the-perils-of-lgplv3.html |title=The perils of LGPLv3 |first=Nikos |last=Mavrogiannopoulos |publisher=gnutls.org |date=2013-03-26 |access-date=2015-11-18 |quote=LGPLv3 is the latest version of the GNU Lesser General Public License. It follows the successful LGPLv2.1 license, and was released by Free Software Foundation as a counterpart to its GNU General Public License version 3. The goal of the GNU Lesser General Public Licenses is to provide software that can be used by both proprietary and free software. This goal has been successfully handled so far by LGPLv2.1, and there is a multitude of libraries using that license. Now we have LGPLv3 as the latest, and the question is how successful is LGPLv3 on this goal? In my opinion, very little. If we assume that its primary goal is to be used by free software, then it blatantly fails that.}}[http://upstream.rosalinux.ru/changelogs/gnutls/3.2.1/changelog.html Version 2.99.4] (released 2011-07-23)[...] ** libgnutls: license upgraded to LGPLv3[http://www.gnutls.org/abi-tracker/changelog/gnutls/3.1.10/log.html 2013-03-14 Nikos Mavrogiannopoulos (nmav@gnutls.org)] * COPYING.LESSER, README: gnutls 3.1.10 is LGPLv2.1

The GNU Free Documentation License in version 1.2 is not compatible with the widely used Creative Commons Attribution-ShareAlike license, which was a problem, for instance, for the Wikipedia.[http://notablog.notafish.com/post/2005/04/21/26-why-the-wikimedia-projects-should-not-use-gfdl-as-a-stand-alone-license-for-images why-the-wikimedia-projects-should-not-use-gfdl-as-a-stand-alone-license-for-images] Therefore, at the request of the Wikimedia Foundation, the FSF added, with version 1.3 of the GFDL, a time-limited section allowing specific types of websites using the GFDL to additionally offer their work under the CC BY-SA license.{{cite web|url=https://www.gnu.org/licenses/fdl-1.3-faq.html |title=FDL 1.3 FAQ |publisher=Gnu.org |access-date=2011-11-07}} Following in June 2009, the Wikimedia Foundation migrated their projects (Wikipedia, etc.) by dual licensing to the Creative Commons Attribution-ShareAlike as main license, additional to the previously used GFDL.{{cite web|url=https://wikimediafoundation.org/wiki/Resolution:Licensing_update_approval|title=Resolution:Licensing update approval - Wikimedia Foundation}} An improved license compatibility with the greater free content ecosystem was given as reason for the license change.[https://creativecommons.org/weblog/entry/15411 Wikipedia + CC BY-SA = Free Culture Win!] on creativecommons.org by Mike Linksvayer, June 22nd, 2009[http://blog.wikimedia.org/2009/06/30/licensing-update-rolled-out-in-all-wikimedia-wikis/ Licensing update rolled out in all Wikimedia wikis] on wikimedia.org by Erik Moeller on June 30th, 2009 "Perhaps the most significant reason to choose CC-BY-SA as our primary content license was to be compatible with many of the other admirable endeavors out there to share and develop free knowledge"

In 2010 the OGRE project changed their license from the LGPL to the MIT License; a simpler license text was given as reason.[http://www.ogre3d.org/licensing/licensing-faq Licensing FAQ] on ogre3d.org[http://www.stevestreeting.com/2009/09/15/my-evolving-view-of-open-source-licenses/ My evolving view of open source licenses] by Steve (2009/09/15)[http://www.ogre3d.org/forums/viewtopic.php?f=1&t=52538 OGRE Will Switch To The MIT License from 1.7] on ogre3d.org by sinbad (Sep 15, 2009)

Another case was the relicensing of GPLv2 licensed Linux kernel header files to the BSD license by Google for their Android library Bionic. To get rid of the GPL, Google claimed that the header files were cleaned from any copyright-able work, reducing them to non-copyrightable "facts".[https://www.theregister.co.uk/2011/03/29/google_android_and_the_linux_headers/ Google android and the linux headers] on theregister.com (2011)[http://www.itworld.com/article/2744480/open-source-tools/android--sued-by-microsoft--not-by-linux.html Android: Sued by Microsoft, not by Linux] "Microsoft launches new Android suit, Linus Torvalds' take on Linux kernel headers and Android" on ITworld (March 21, 2011) This interpretation was challenged for instance by Raymond Nimmer, a law professor at the University of Houston Law Center.[http://www.ipinfoblog.com/archives/licensing-law-issues-infringement-and-disclosure-risk-in-development-on-copyleft-platforms.html Infringement and disclosure risk in development on copyleft platforms] on ipinfoblog.com by Raymond Nimmer (2011)

In November 2013 POV-Ray was relicensed under the GNU Affero General Public License version 3 (or later),{{cite web| url=http://www.povray.org/download/ | title=Download POV-Ray 3.7.0 | last=Cason |first=Chris | date=8 November 2013 | quote=Starting with version 3.7, POV-Ray is released under the AGPL3 (or later) license and thus is Free Software according to the FSF definition. […] Full source code is available, allowing users to build their own versions and for developers to incorporate portions or all of the POV-Ray source into their own software provided it is distributed under a compatible license (for example, the AGPL3 or – at their option – any later version). | access-date=11 November 2013}} after being distributed since 1991 under a FOSS-incompatible, non-commercial source available custom POV-Ray license.{{cite web|url=http://www.povray.org/distribution-license-3.6.html |title=POV-Ray 3.6 Distribution License |publisher=Povray.org |access-date=2016-12-12}}{{cite web|url=http://www.povray.org/source-license-3.6.html |title=POV-Ray 3.6 Source License |publisher=Povray.org |access-date=2016-12-12}} POV-Ray was developed before FOSS licenses became widely used, therefore the developers wrote their own license which became later a problem due to license incompatibility with the FOSS ecosystem.

In 2014, the FreeCAD project changed their license from GPL to LGPLv2 due to GPLv3/GPLv2 incompatibilities.{{cite web |url=https://librearts.org/2012/12/libredwg-drama-the-end-or-the-new-beginning/ |title=LibreDWG drama: the end or the new beginning? |first=Alexandre |last=Prokoudine |date=2012-12-27 |quote=[...]the unfortunate situation with support for DWG files in free CAD software via LibreDWG. We feel, by now it ought to be closed. We have the final answer from FSF. [...] "We are not going to change the license." |access-date=2025-03-09 |publisher=librearts.org }}{{cite web|url=http://www.freecadweb.org/wiki/index.php?title=Licence |title=license |quote=Licences used in FreeCAD - FreeCAD uses two different licenses, one for the application itself, and one for the documentation: Lesser General Public Licence, version 2 or superior (LGPL2+) […] Open Publication Licence |publisher=freecadweb.org |access-date=2015-03-25 |date=2014}}

In 2014 Gang Garrison 2 relicensed from GPLv3 to MPL for improved library compatibility.{{cite web|website=GitHub|url=https://github.com/Medo42/Gang-Garrison-2/blob/master/License.txt |title=Gang-Garrison-2/License.txt|date=2014-11-09 |access-date=2015-03-23}}{{cite web|website=Gang Garrison 2 Forums|url=http://www.ganggarrison.com/forums/index.php?topic=35995.0|title=Planned license change (GPL -> MPL), Help needed |date=2014-08-23 |access-date=2015-03-23|quote=tl;dr: The current license prevents us from using certain nice and (cost-)free libraries / frameworks, so we want to change it. The new license (MPL) would be strictly more free than the old one, and is the same one that's also used by Firefox.}}

In May 2015 the Dolphin project changed its license from "GPLv2 only" to "GPLv2 or any later" for better compatibility.[https://dolphin-emu.org/blog/2015/05/25/relicensing-dolphin/ Relicensing Dolphin: The long road to GPLv2+] Written by JMC47, MaJoR on May 25, 2015

In June 2015 mpv started the relicensation process of the project's GPL licensed source code for improved license compatibility under LGPLv2 by getting consent from the majority (95%+) of the contributing developers.[https://github.com/mpv-player/mpv/issues/2033 Possible LGPL relicensing #2033] on github.com "GPL-incompatible dependencies such as OpenSSL are a big issue for library users, even if the library user is ok with the GPL." In August 2016 approx. 90% of the authors could be reached and consented. In October 2017 the switch was finalized.[https://github.com/mpv-player/mpv/issues/2033#issuecomment-335511905 The LGPL relicensing is "official" now, and git master now has a --enable-lgpl configure option.] by wm4 on github.com

In July 2015 Seafile switched for improved license compatibility, especially with Git, from the GPLv3 to the GPLv2.{{cite web|url=https://www.seafile-server.org/en/switchin-from-gplv3-to-gplv2/|title=switchin-from-gplv3-to-gplv2}}{{cite web|url=https://github.com/haiwen/seafile/blob/master/LICENSE.txt|title=haiwen/seafile|website=GitHub }}

In 2015 Natron was relicensed from MPL to the GPLv2 to allow better commercialization.[https://forum.natron.fr/t/why-change-natron-licence-to-gpl-v2/160 Why change Natron licence to GPL V2? Can you explain your motivation ? Why change from Mozilla to GPL ?] {{Webarchive|url=https://web.archive.org/web/20170306210341/https://forum.natron.fr/t/why-change-natron-licence-to-gpl-v2/160 |date=2017-03-06 }} on natron.fr MrKepzieLeader: "The main reasoning is that in the future there will be derivative work spun off Natron, and we want to be able to still control where our source code is going and who is selling it." (Aug 2015)

In 2016 MAME achieved a relicensing of the code base to BSD/GPL[http://mamedev.org/?p=422 MAME is now Free and Open Source Software] on mamedev.org (March 4, 2016) after struggling for years with an own written custom license, with non-commercial license terms.[https://web.archive.org/web/20131031202643/http://mamedev.emulab.it/haze/2013/10/25/the-already-dead-theory the-already-dead-theory] on mamedev.emulab.it[http://www.mameworld.info/ubbthreads/showflat.php?Number=316273 So why did this annoy me so much?] on mameworld.info (10/22/13){{cite web|title=10 months later, MAME finishes its transition to open source|url=http://gamasutra.com/view/news/267316/10_months_later_MAME_finishes_its_transition_to_open_source.php |website=Gamasutra |access-date=5 March 2016}}{{cite news |title=MAME is going open source to be a 'learning tool for developers' |url=http://gamasutra.com/view/news/243598/MAME_is_going_open_source_to_be_a_learning_tool_for_developers.php |website=Gamasutra |publisher=UBM plc |access-date=27 May 2015}}

In August 2016 the MariaDB Corporation relicensed the database proxy server MaxScale from GPL to the non-FOSS but source-available and time-limited Business source license (BSL)[https://mariadb.com/bsl bsl] "Change Date: 2019-01-01, Change License: Version 2 or later of the GNU General Public License as published by the Free Software Foundation." on mariadb.com (August 2016) which defaults back after three years to GPL.[https://www.theregister.co.uk/2016/08/24/monty_interview/ MySQL daddy Widenius: Open-source religion won't feed MariaDB] on theregister.com (August 2016)[http://www.infoworld.com/article/3109213/open-source-tools/open-source-uproar-as-mariadb-goes-commercial.html A new release of the MaxScale database proxy -- essential to deploying MariaDB at scale -- features a proprietary license] on InfoWorld by Simon Phipps (Aug 19, 2016) In 2017 followed version 1.1, revised with feedback also from Bruce Perens.[https://perens.com/2017/02/14/bsl-1-1/ sl-1-1] on perens.com (2017-02-14)[https://mariadb.com/resources/blog/releasing-bsl-11 releasing-bsl-11] on mariadb.com by Kaj Arnö (2017)

For a long time D back-end source code was available but under a non-open source conform license,{{cite web | url=https://github.com/dlang/dmd/blob/master/src/backendlicense.txt | title=backendlicense.txt | publisher=GitHub | work=DMD source code | access-date=5 March 2012 | url-status=dead | archive-url=https://archive.today/20161022202138/https://github.com/dlang/dmd/blob/master/src/backendlicense.txt | archive-date=22 October 2016 }} because it was partially developed at Symantec and couldn't be relicensed as open source.{{cite web | url=https://www.reddit.com/r/programming/comments/82cgp/new_release_of_the_d_programming_language_now/c082539 | title=Reddit comment by Walter Bright | date=5 March 2009 | access-date=9 September 2014}} On April 9, 2017, also the back-end part could be relicensed to the open-source Boost Software License.[http://www.linux-magazin.de/NEWS/D-Compiler-unter-freier-Lizenz D-Compiler-unter-freier-Lizenz] on linux-magazin.de (2017, in German){{cite web|url=https://forum.dlang.org/post/oc8acc$1ei9$1@digitalmars.com|title=dmd Backend converted to Boost License|date=7 April 2017|access-date=9 April 2017}}[https://github.com/dlang/dmd/pull/6680 switch backend to Boost License #6680] from Walter Bright on github.com

On July 27, 2017 Microsoft Research changed the license of space combat simulator Allegiance from the MSR shared source license,[http://freespacecombatgame.com/allegiancelicense.txt allegiancelicense.txt] {{webarchive|url=https://web.archive.org/web/20141107171657/http://freespacecombatgame.com/allegiancelicense.txt |date=7 November 2014 }} Microsoft Research Shared Source license agreement ("MSR-SSLA") under which the game was opened in 2004,{{Cite web|last=Colayco |first=Bob |title=Microsoft pledges Allegiance to its fanbase |publisher=gamespot.com |access-date=2011-07-22 |date=2004-02-06 |url=http://www.gamespot.com/pc/sim/allegiance/news.html?sid=6087574&om_act=convert&om_clk=newsfeatures&tag=newsfeatures;title;1 |url-status=live |archive-url=https://web.archive.org/web/20131210103542/http://www.gamespot.com/articles/microsoft-pledges-allegiance-to-its-fanbase/1100-6087574/ |archive-date=10 December 2013 }} to the MIT license.{{Cite web| last = Horvitz| first = Eric | title = Allegiance Relicense Letter| publisher = Director, Microsoft Research | access-date = 2017-07-28| date = 2017-07-28| url = https://github.com/FreeAllegiance/Allegiance/blob/master/src/AllegianceRelicenseLetter.pdf |quote=Microsoft Corporation ("Microsoft") hereby relicenses the Microsoft Video Game Allegiance source code found at https://github.com/FreeAllegiance/Allegiance/tree/master/src ("Allegiance Source Code") from the current Microsoft Research Shared Source license Agreement (MSR-SSLA) to the MIT license.}}[https://www.freeallegiance.org/forums/index.php?showtopic=72206 FREEING Allegiance, How it Happened (sort of)] on freeallegiance.org (2017-07-28)

• License compatibility
• Backward compatibility
• Forward compatibility
• License proliferation

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Category:Copyright licenses