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GNU General Public License

October 20, 2023

The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software.[1] The license was the first copyleft for general use and was originally written by Richard Stallman, the founder of the Free Software Foundation (FSF), for the GNU Project. The license grants the recipients of a computer program the rights of the Free Software Definition.[2] These GPL series are all copyleft licenses, which means that any derivative work must be distributed under the same or equivalent license terms. It is more restrictive than the Lesser General Public License and even further distinct from the more widely used permissive software licenses BSD, MIT, and Apache.

Logo for version 3 of the license

Historically, the GPL license family has been one of the most popular software licenses in the free and open-source software (FOSS) domain.[1][3][4][5][6] Prominent free software programs licensed under the GPL include the Linux kernel and the GNU Compiler Collection (GCC). David A. Wheeler argues that the copyleft provided by the GPL was crucial to the success of Linux-based systems, giving the programmers who contributed to the kernel the assurance that their work would benefit the whole world and remain free, rather than being exploited by software companies that would not have to give anything back to the community.[7]

In 2007, the third version of the license (GPLv3) was released to address some perceived problems with the second version (GPLv2) which were discovered during the latter's long-time usage.

To keep the license up to date, the GPL license includes an optional "any later version" clause, allowing users to choose between the original terms or the terms in new versions as updated by the FSF. Software projects licensed with the optional "or later" clause include the GNU Project, while the Linux kernel, for instance, is licensed under GPLv2 only.

The "or any later version" clause is sometimes known as a lifeboat clause since it allows combinations between different versions of GPL licensed software to maintain compatibility.

History Edit

The GPL was written by Richard Stallman in 1989, for use with programs released as part of the GNU project. The original GPL was based on a unification of similar licenses used for early versions of GNU Emacs (1985),[8] the GNU Debugger, and the GNU C Compiler.[9] These licenses contained similar provisions to the modern GPL, but were specific to each program, rendering them incompatible, despite being the same license.[10] Stallman's goal was to produce one license that could be used for any project, thus making it possible for many projects to share code.

The second version of the license, version 2, was released in 1991. Over the following 15 years, members of the free software community became concerned over problems in the GPLv2 license that could let someone exploit GPL-licensed software in ways contrary to the license's intent.[11] These problems included tivoization (the inclusion of GPL-licensed software in hardware that refuses to run modified versions of its software), compatibility issues similar to those of the Affero General Public License, and patent deals between Microsoft and distributors of free and open-source software, which some viewed as an attempt to use patents as a weapon against the free software community.

Version 3 was developed to attempt to address these concerns and was officially released on 29 June 2007.[12]

Version 1 Edit

GNU General Public License, version 1
Published25 February 1989
Websitewww.gnu.org/licenses/old-licenses/gpl-1.0.html

Version 1 of the GNU GPL,[13] released on 25 February 1989,[14] prevented what were then the two main ways that software distributors restricted the freedoms that define free software. The first problem was that distributors may publish only binary files that are executable, but not readable or modifiable by humans. To prevent this, GPLv1 stated that copying and distributing copies of any portion of the program must also make the human-readable source code available under the same licensing terms.[a]

The second problem was that distributors might add restrictions, either to the license or by combining the software with other software that had other restrictions on distribution. The union of two sets of restrictions would apply to the combined work, thus adding unacceptable restrictions. To prevent this, GPLv1 stated that modified versions, as a whole, had to be distributed under the terms of GPLv1.[b] Therefore, software distributed under the terms of GPLv1 could be combined with software under more permissive terms, as this would not change the terms under which the whole could be distributed. However, software distributed under GPLv1 could not be combined with software distributed under a more restrictive license, as this would conflict with the requirement that the whole be distributable under the terms of GPLv1.

Version 2 Edit

GNU General Public License, version 2
PublishedJune 1991
Websitewww.gnu.org/licenses/old-licenses/gpl-2.0.html

According to Richard Stallman, the major change in GPLv2 was the "Liberty or Death" clause, as he calls it[10] – Section 7. The section says that licensees may distribute a GPL-covered work only if they can satisfy all of the license's obligations, despite any other legal obligations they might have. In other words, the obligations of the license may not be severed due to conflicting obligations. This provision is intended to discourage any party from using a patent infringement claim or other litigation to impair users' freedom under the license.[10]

By 1990, it was becoming apparent that a less restrictive license would be strategically useful for the C library and for software libraries that essentially did the job of existing proprietary ones;[15] when version 2 of the GPL (GPLv2) was released in June 1991, therefore, a second license – the GNU Library General Public License – was introduced at the same time and numbered with version 2 to show that both were complementary.[16] The version numbers diverged in 1999 when version 2.1 of the LGPL was released, which renamed it the GNU Lesser General Public License to reflect its place in the philosophy. The GPLv2 was also modified to refer to the new name of the LGPL, but its version number remained the same, resulting in the original GPLv2 not being recognised by the Software Package Data Exchange (SPDX).[17][failed verification]

The license includes instructions to specify "version 2 of the License, or (at your option) any later version" to allow the flexible optional use of either version 2 or 3, but some developers change this to specify "version 2" only.

Version 3 Edit

GNU General Public License, version 3
Published29 June 2007
Websitewww.gnu.org/licenses/gpl-3.0.html

In late 2005, the Free Software Foundation (FSF) announced work on version 3 of the GPL (GPLv3). On 16 January 2006, the first "discussion draft" of GPLv3 was published, and the public consultation began. The public consultation was originally planned for nine to fifteen months, but finally stretched to eighteen months with four drafts being published. The official GPLv3 was released by the FSF on 29 June 2007. GPLv3 was written by Richard Stallman, with legal counsel from Eben Moglen and Richard Fontana from the Software Freedom Law Center.[18][19]

According to Stallman, the most important changes were in relation to software patents, free software license compatibility, the definition of "source code", and hardware restrictions on software modifications, such as tivoization.[18][20] Other changes related to internationalization, how license violations are handled, and how additional permissions could be granted by the copyright holder. The concept of "software propagation", as a term for the copying and duplication of software, was explicitly defined.

The public consultation process was coordinated by the Free Software Foundation with assistance from Software Freedom Law Center, Free Software Foundation Europe,[21] and other free software groups. Comments were collected from the public via the gplv3.fsf.org web portal,[22] using purpose-written software called stet.

During the public consultation process, 962 comments were submitted for the first draft.[23] By the end of the comment period, a total of 2,636 comments had been submitted.[24]

The third draft was released on 28 March 2007.[25] This draft included language intended to prevent patent-related agreements such as the controversial Microsoft-Novell patent agreement, and restricted the anti-tivoization clauses to a legal definition of a "user" and a "consumer product". It also explicitly removed the section on "Geographical Limitations", whose probable removal had been announced at the launch of the public consultation.

 
Richard Stallman at the launch of the first draft of the GNU GPLv3 at MIT, Cambridge, Massachusetts, United States. To his right is Columbia Law Professor Eben Moglen, chairman of the Software Freedom Law Center.

The fourth discussion draft,[26] which was the last, was released on 31 May 2007. It introduced Apache License version 2.0 compatibility (prior versions are incompatible), clarified the role of outside contractors and made an exception to avoid the perceived problems of a Microsoft–Novell style agreement, saying in Section 11 paragraph 6 that:

You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software, under which you make payment to the third party based on the extent of your activity of conveying the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a discriminatory patent license ...

This aimed to make future such deals ineffective. The license was also meant to cause Microsoft to extend the patent licenses it granted to Novell customers for the use of GPLv3 software to all users of that GPLv3 software; this was possible only if Microsoft was legally a "conveyor" of the GPLv3 software.[27]

Early drafts of GPLv3 also let licensors add an Affero-like requirement that would have plugged the ASP loophole in the GPL.[28][29] As there were concerns expressed about the administrative costs of checking code for this additional requirement, it was decided to keep the GPL and the Affero license separated.[30]

Others, notably some high-profile Linux kernel developers such as Linus Torvalds, Greg Kroah-Hartman, and Andrew Morton, commented to the mass media and made public statements about their objections to parts of discussion drafts 1 and 2.[31] The kernel developers referred to GPLv3 draft clauses regarding DRM/Tivoization, patents, and "additional restrictions", and warned of a Balkanisation of the "Open Source Universe".[31][32] Linus Torvalds, who decided not to adopt the GPLv3 for the Linux kernel,[33] reiterated his criticism several years later.[34][35]

GPLv3 improved compatibility with several free software licenses such as the Apache License, version 2.0, and the GNU Affero General Public License, which GPLv2 could not be combined with.[36] However, GPLv3 software could only be combined and share code with GPLv2 software if the GPLv2 license used had the optional "or later" clause and the software was upgraded to GPLv3. While the "GPLv2 or any later version" clause is considered by FSF as the most common form of licensing GPLv2 software,[37] Toybox developer Rob Landley described it as a lifeboat clause.[c] Software projects licensed with the optional "or later" clause include the GNU Project,[citation needed] while a prominent example without the clause is the Linux kernel.[33][40]

The final version of the license text was published on 29 June 2007.[41]

Terms and conditions Edit

The terms and conditions of the GPL must be made available to anybody receiving a copy of the work that has a GPL applied to it ("the licensee"). Any licensee who adheres to the terms and conditions is given permission to modify the work, as well as to copy and redistribute the work or any derivative version. The licensee is allowed to charge a fee for this service or do this free of charge. This latter point distinguishes the GPL from software licenses that prohibit commercial redistribution. The FSF argues that free software should not place restrictions on commercial use,[42] and the GPL explicitly states that GPL works may be sold at any price.

The GPL additionally states that a distributor may not impose "further restrictions on the rights granted by the GPL". This forbids activities such as distributing the software under a non-disclosure agreement or contract.

The fourth section for version 2 of the license and the seventh section of version 3 require that programs distributed as pre-compiled binaries be accompanied by a copy of the source code, a written offer to distribute the source code via the same mechanism as the pre-compiled binary, or the written offer to obtain the source code that the user got when they received the pre-compiled binary under the GPL. The second section of version 2 and the fifth section of version 3 also require giving "all recipients a copy of this License along with the Program". Version 3 of the license allows making the source code available in additional ways in fulfillment of the seventh section. These include downloading source code from an adjacent network server or by peer-to-peer transmission, provided that is how the compiled code was available and there are "clear directions" on where to find the source code.

The FSF does not hold the copyright for a work released under the GPL unless an author explicitly assigns copyrights to the FSF (which seldom happens except for programs that are part of the GNU project). Only the individual copyright holders have the authority to sue when a license violation is suspected.

 
Printed GPL statements for consumer entertainment devices which incorporate GPL components

Use of licensed software Edit

Software under the GPL may be run for all purposes, including commercial purposes and even as a tool for creating proprietary software, such as when using GPL-licensed compilers.[43] Users or companies who distribute GPL-licensed works (e.g. software), may charge a fee for copies or give them free of charge. This distinguishes the GPL from shareware software licenses that allow copying for personal use but prohibit the commercial distribution or proprietary licenses where copying is prohibited by copyright law. The FSF argues that freedom-respecting free software should also not restrict commercial use and distribution (including redistribution):[42]

In purely private (or internal) use—with no sales and no distribution—the software code may be modified and parts reused without requiring the source code to be released. For sales or distribution, the entire source code needs to be made available to end users, including any code changes and additions—in that case, copyleft is applied to ensure that end users retain the freedoms defined above.[44]

However, software running as an application program under a GPL-licensed operating system such as Linux is not required to be licensed under GPL or to be distributed with source-code availability—the licensing depends only on the used libraries and software components and not on the underlying platform.[45] For example, if a program consists only of original source code, or is combined with source code from other software components,[d] then the custom software components need not be licensed under GPL and need not make their source code available; even if the underlying operating system used is licensed under the GPL, applications running on it are not considered derivative works.[45] Only if GPLed parts are used in a program (and the program is distributed), then all other source code of the program needs to be made available under the same license terms. The GNU Lesser General Public License (LGPL) was created to have a weaker copyleft than the GPL, in that it does not require custom-developed source code (distinct from the LGPL'ed parts) to be made available under the same license terms.

The fifth section of version 3 states that no GPL-licensed code shall be considered an effective "technical protection measure" as defined by Article 11 of the WIPO Copyright Treaty, and that those who convey the work waive all legal power to prohibit circumvention of the technical protection measure "to the extent such circumvention is effected by exercising rights under this License with respect to the covered work". This means that users cannot be held liable for circumventing DRM implemented using GPLv3-licensed code under laws such as the U.S. Digital Millennium Copyright Act (DMCA).[46]

Copyleft Edit

Main article: Copyleft

The distribution rights granted by the GPL for modified versions of the work are not unconditional. When someone distributes a GPL'ed work plus their own modifications, the requirements for distributing the whole work cannot be any greater than the requirements that are in the GPL.

This requirement is known as copyleft. It earns its legal power from the use of copyright on software programs. Because a GPL work is copyrighted, a licensee has no right to redistribute it, not even in modified form (barring fair use), except under the terms of the license. One is only required to adhere to the terms of the GPL if one wishes to exercise rights normally restricted by copyright law, such as redistribution. Conversely, if one distributes copies of the work without abiding by the terms of the GPL (for instance, by keeping the source code secret), they can be sued by the original author under copyright law.

Copyright law has historically been used to prevent distribution of work by parties not authorized by the creator. Copyleft uses the same copyright laws to accomplish a very different goal. It grants rights to distribution to all parties insofar as they provide the same rights to subsequent ones, and they to the next, etc. In this way the GPL and other copyleft licenses attempt to enforce libre access to the work and all derivatives.[47]

Many distributors of GPL'ed programs bundle the source code with the executables. An alternative method of satisfying the copyleft is to provide a written offer to provide the source code on a physical medium (such as a CD) upon request. In practice, many GPL'ed programs are distributed over the Internet, and the source code is made available over FTP or HTTP. For Internet distribution, this complies with the license.

Copyleft applies only when a person seeks to redistribute the program. Developers may make private modified versions with no obligation to divulge the modifications, as long as they do not distribute the modified software to anyone else. Copyleft applies only to the software, and not to its output (unless that output is itself a derivative work of the program).[e] For example, a public web portal running a modified derivative of a GPL'ed content management system is not required to distribute its changes to the underlying software, because the modified web portal is not being redistributed but rather hosted, and also because the web portal output is also not a derivative work of the GPL'ed content management system.

There has been debate on whether it is a violation of the GPL to release the source code in obfuscated form, such as in cases in which the author is less willing to make the source code available. The consensus was that while unethical, it was not considered a violation. The issue was clarified when the license was altered with v2 to require that the "preferred" version of the source code be made available.[49]

License versus contract Edit

The GPL was designed as a license, rather than a contract.[50] In some Common Law jurisdictions, the legal distinction between a license and a contract is an important one: contracts are enforceable by contract law, whereas licenses are enforced under copyright law. However, this distinction is not useful in the many jurisdictions where there are no differences between contracts and licenses, such as Civil Law systems.[51]

Those who do not accept the GPL's terms and conditions do not have permission, under copyright law, to copy or distribute GPL-licensed software or derivative works. However, if they do not redistribute the GPL'ed program, they may still use the software within their organization however they like, and works (including programs) constructed by the use of the program are not required to be covered by this license.

Software developer Allison Randal argued that the GPLv3 as a license is unnecessarily confusing for lay readers, and could be simplified while retaining the same conditions and legal force.[52]

In April 2017, a US federal court ruled that an open-source license is an enforceable contract.[53]

In October 2021 SFC sued Vizio over breach of contract as an end user to request source code to Vizio's TVs, a federal judge has ruled in the interim that the GPL is an enforceable contract by end users as well as a license for copyright holders.[54]

Derivations Edit

The text of the GPL is itself copyrighted, and the copyright is held by the Free Software Foundation.

The FSF permits people to create new licenses based on the GPL, as long as the derived licenses do not use the GPL preamble without permission. This is discouraged, however, since such a license might be incompatible with the GPL[55] and causes a perceived license proliferation.

Other licenses created by the GNU project include the GNU Lesser General Public License, GNU Free Documentation License, and Affero General Public License.

The text of the GPL is not itself under the GPL. The license's copyright disallows modification of the license. Copying and distributing the license is allowed since the GPL requires recipients to get "a copy of this License along with the Program".[56] According to the GPL FAQ, anyone can make a new license using a modified version of the GPL as long as they use a different name for the license, do not mention "GNU", and remove the preamble, though the preamble can be used in a modified license if permission to use it is obtained from the Free Software Foundation (FSF).[57]

Linking and derived works Edit

Libraries Edit

According to the FSF, "The GPL does not require you to release your modified version or any part of it. You are free to make modifications and use them privately, without ever releasing them."[58] However, if one releases a GPL-licensed entity to the public, there is an issue regarding linking: namely, whether a proprietary program that uses a GPL library is in violation of the GPL.

This key dispute is whether non-GPL software can legally statically link or dynamically link to GPL libraries. Different opinions exist on this issue. The GPL is clear in requiring that all derivative works of code under the GPL must themselves be under the GPL. Ambiguity arises with regards to using GPL libraries, and bundling GPL software into a larger package (perhaps mixed into a binary via static linking). This is ultimately a question not of the GPL per se, but of how copyright law defines derivative works. The following points of view exist:

Point of view: dynamic and static linking violate GPL Edit

The Free Software Foundation (which holds the copyright of several notable GPL-licensed software products and of the license text itself) asserts that an executable that uses a dynamically linked library is indeed a derivative work. This does not, however, apply to separate programs communicating with one another.[59]

The Free Software Foundation also created the LGPL, which is nearly identical to the GPL, but with additional permissions to allow linking for the purposes of "using the library".

Richard Stallman and the FSF specifically encourage library writers to license under the GPL so that proprietary programs cannot use the libraries, in an effort to protect the free-software world by giving it more tools than the proprietary world.[60]

Point of view: static linking violates GPL but unclear as of dynamic linking Edit

Some people believe that while static linking produces derivative works, it is not clear whether an executable that dynamically links to a GPL code should be considered a derivative work (see weak copyleft). Linux author Linus Torvalds agrees that dynamic linking can create derived works but disagrees over the circumstances.[61]

A Novell lawyer has written that dynamic linking not being derivative "makes sense" but is not "clear-cut", and that evidence for good-intentioned dynamic linking can be seen by the existence of proprietary Linux kernel drivers.[62]

In Galoob v. Nintendo, the United States Ninth Circuit Court of Appeals defined a derivative work as having "'form' or permanence" and noted that "the infringing work must incorporate a portion of the copyrighted work in some form",[63] but there have been no clear court decisions to resolve this particular conflict.

Point of view: linking is irrelevant Edit

According to an article in the Linux Journal, Lawrence Rosen (a one-time Open Source Initiative general counsel) argues that the method of linking is mostly irrelevant to the question about whether a piece of software is a derivative work; more important is the question about whether the software was intended to interface with client software and/or libraries.[64] He states, "The primary indication of whether a new program is a derivative work is whether the source code of the original program was used [in a copy-paste sense], modified, translated or otherwise changed in any way to create the new program. If not, then I would argue that it is not a derivative work,"[64] and lists numerous other points regarding intent, bundling, and linkage mechanism. He further argues on his firm's website[65] that such "market-based" factors are more important than the linking technique.

There is also the specific issue of whether a plugin or module (such as the NVidia or ATI graphics card kernel modules) must also be GPL, if it could reasonably be considered its own work. This point of view suggests that reasonably separate plugins, or plugins for software designed to use plugins, could be licensed under an arbitrary license if the work is GPLv2. Of particular interest is the GPLv2 paragraph:

You may modify your copy or copies of the Program or any portion of it, thus forming a work based on the Program, and copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions: ...

b) You must cause any work that you distribute or publish, that in whole or in part contains or is derived from the Program or any part thereof, to be licensed as a whole at no charge to all third parties under the terms of this License. ... These requirements apply to the modified work as a whole. If identifiable sections of that work are not derived from the Program and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. But when you distribute the same sections as part of a whole which is a work based on the Program, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it.

The GPLv3 has a different clause:

You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source code under the terms of Section 4, provided that you also meet all of these conditions: ...

c) You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable Section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it. ... A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an "aggregate" if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation's users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate.

As a case study, some supposedly proprietary plugins and themes/skins for GPLv2 CMS software such as Drupal and WordPress have come under fire, with both sides of the argument taken.[66]

The FSF differentiates on how the plugin is being invoked. If the plugin is invoked through dynamic linkage and it performs function calls to the GPL program then it is most likely a derivative work.[67]

Communicating and bundling with non-GPL programs Edit

The mere act of communicating with other programs does not, by itself, require all software to be GPL; nor does distributing GPL software with non-GPL software. However, minor conditions must be followed that ensures the rights of GPL software are not restricted. The following is a quote from the gnu.org GPL FAQ, which describes to what extent software is allowed to communicate with and be bundled with GPL programs:[68]

What is the difference between an "aggregate" and other kinds of "modified versions"?

An "aggregate" consists of a number of separate programs, distributed together on the same CD-ROM or other media. The GPL permits you to create and distribute an aggregate, even when the licenses of the other software are non-free or GPL-incompatible. The only condition is that you cannot release the aggregate under a license that prohibits users from exercising rights that each program's individual license would grant them.

Where's the line between two separate programs, and one program with two parts? This is a legal question, which ultimately judges will decide. We believe that a proper criterion depends both on the mechanism of communication (exec, pipes, rpc, function calls within a shared address space, etc.) and the semantics of the communication (what kinds of information are interchanged).

If the modules are included in the same executable file, they are definitely combined in one program. If modules are designed to run linked together in a shared address space, that almost surely means combining them into one program.

By contrast, pipes, sockets, and command-line arguments are communication mechanisms normally used between two separate programs. So when they are used for communication, the modules normally are separate programs. But if the semantics of the communication are intimate enough, exchanging complex internal data structures, that too could be a basis to consider the two parts as combined into a larger program.

The FSF thus draws the line between "library" and "other program" via 1) "complexity" and "intimacy" of information exchange and 2) mechanism (rather than semantics), but resigns that the question is not clear-cut and that in complex situations, case law will decide.

Legal status Edit

See also: SCO-Linux controversies and SCO v. IBM

The first known violation of the GPL was in 1989, when NeXT extended the GCC compiler to support Objective-C, but did not publicly release the changes.[69] After an inquiry they created a public patch. There was no lawsuit filed for this violation.[70]

In 2002, MySQL AB sued Progress NuSphere for copyright and trademark infringement in United States district court. NuSphere had allegedly violated MySQL's copyright by linking MySQL's GPL'ed code with NuSphere Gemini table without complying with the license. After a preliminary hearing before Judge Patti Saris on 27 February 2002, the parties entered settlement talks and eventually settled.[f] After the hearing, FSF commented that "Judge Saris made clear that she sees the GNU GPL to be an enforceable and binding license."[71]

In August 2003, the SCO Group stated that they believed the GPL to have no legal validity and that they intended to pursue lawsuits over sections of code supposedly copied from SCO Unix into the Linux kernel. This was a problematic stand for them, as they had distributed Linux and other GPL'ed code in their Caldera OpenLinux distribution, and there is little evidence that they had any legal right to do so except under the terms of the GPL.[citation needed] In February 2018, after federal circuit court judgement, appeal, and the case being (partially) remanded to the circuit court, the parties restated their remaining claims and provided a plan to move toward final judgement.[72] The remaining claims revolved around Project Monterey, and were finally settled in November 2021 by IBM paying $14.25 million to the TSG (previously SCO) bankruptcy trustee.[73]

In April 2004, the netfilter/iptables project was granted a preliminary injunction against Sitecom Germany by Munich District Court after Sitecom refused to desist from distributing Netfilter's GPL'ed software in violation of the terms of the GPL. Harald Welte, of Netfilter, was represented by ifrOSS co-founder Till Jaeger. In July 2004, the German court confirmed this injunction as a final ruling against Sitecom.[74] The court's justification was that:

Defendant has infringed on the copyright of plaintiff by offering the software 'netfilter/iptables' for download and by advertising its distribution, without adhering to the license conditions of the GPL. Said actions would only be permissible if the defendant had a license grant. ... This is independent of the questions whether the licensing conditions of the GPL have been effectively agreed upon between plaintiff and defendant or not. If the GPL were not agreed upon by the parties, defendant would notwithstanding lack the necessary rights to copy, distribute, and make the software 'netfilter/iptables' publicly available.

This exactly mirrored the predictions given previously by the FSF's Eben Moglen. This ruling was important because it was the first time that a court had confirmed that violating terms of the GPL could be a copyright violation and established jurisprudence as to the enforceability of the GPLv2 under German law.[75]

In May 2005, Daniel Wallace filed suit against the Free Software Foundation in the Southern District of Indiana, contending that the GPL is an illegal attempt to fix prices (at zero). The suit was dismissed in March 2006, on the grounds that Wallace had failed to state a valid antitrust claim; the court noted that "the GPL encourages, rather than discourages, free competition and the distribution of computer operating systems, the benefits of which directly pass to consumers".[76] Wallace was denied the possibility of further amending his complaint, and was ordered to pay the FSF's legal expenses.

On 8 September 2005, the Seoul Central District Court ruled that the GPL was not material to a case dealing with trade secrets derived from GPL-licensed work.[77] Defendants argued that since it is impossible to maintain trade secrets while being compliant with GPL and distributing the work, they are not in breach of trade secrets. This argument was considered without ground.

On 6 September 2006, the gpl-violations.org project prevailed in court litigation against D-Link Germany GmbH regarding D-Link's copyright-infringing use of parts of the Linux kernel in storage devices they distributed.[78] The judgment stated that the GPL is valid, legally binding, and stands in German court.[79]

In late 2007, the BusyBox developers and the Software Freedom Law Center embarked upon a program to gain GPL compliance from distributors of BusyBox in embedded systems, suing those who would not comply. These were claimed to be the first US uses of courts for enforcement of GPL obligations. (See BusyBox GPL lawsuits.)

On 11 December 2008, the Free Software Foundation sued Cisco Systems, Inc. for copyright violations by its Linksys division, of the FSF's GPL-licensed coreutils, readline, Parted, Wget, GNU Compiler Collection, binutils, and GNU Debugger software packages, which Linksys distributes in the Linux firmware[80] of its WRT54G wireless routers, as well as numerous other devices including DSL and Cable modems, Network Attached Storage devices, Voice-Over-IP gateways, virtual private network devices, and a home theater/media player device.[81]

After six years of repeated complaints to Cisco by the FSF, claims by Cisco that they would correct, or were correcting, their compliance problems (not providing complete copies of all source code and their modifications), of repeated new violations being discovered and reported with more products, and lack of action by Linksys (a process described on the FSF blog as a "five-years-running game of Whack-a-Mole"[81]) the FSF took them to court.

Cisco settled the case six months later by agreeing "to appoint a Free Software Director for Linksys" to ensure compliance, "to notify previous recipients of Linksys products containing FSF programs of their rights under the GPL," to make source code of FSF programs freely available on its website, and to make a monetary contribution to the FSF.[82]

In 2011, it was noticed that GNU Emacs had been accidentally releasing some binaries without corresponding source code for two years, in opposition to the intended spirit of the GPL, resulting in a copyright violation.[83] Richard Stallman described this incident as a "very bad mistake",[84] which was promptly fixed. The FSF did not sue any downstream redistributors who also unknowingly violated the GPL by distributing these binaries.

In 2017 Artifex, the maker of Ghostscript, sued Hancom, the maker of an office suite which included Ghostscript. Artifex offers two licenses for Ghostscript; one is the Affero GPL License and the other is a commercial license. Hancom did not acquire a commercial license from Artifex nor did it release its office suite as free software. Artifex sued Hancom in US District Court and made two claims. First, Hancom's use of Ghostscript was a violation of copyright; and second, Hancom's use of Ghostscript was a license violation. Judge Jacqueline Scott Corley found the GPL license was an enforceable contract and Hancom was in breach of contract.[85][86]

On 20 July 2021, the developers of the open-source Stockfish chess engine sued ChessBase, the creator of chess software, for violating the GPLv3 license.[87] It was claimed that Chessbase had made only slight modifications to the Stockfish code and sold the new engines (Fat Fritz 2 and Houdini 6) to their customers.[88] Additionally, Fat Fritz 2 was marketed as if it was an innovative engine. ChessBase had infringed on the license by not distributing these products as Free Software in accordance with the GPL.

A year later on 7 November 2022, both parties reached an agreement and ended the dispute. In the near future ChessBase will no longer sell products containing Stockfish code, while informing their customers of this fact with an appropriate notice on their web pages. However, one year later, Chessbase's license would be reinstated. Stockfish did not seek damages or financial compensation.[89][90][91]

Compatibility and multi-licensing Edit

 
Quick guide of license compatibility with GPLv3 according to the FSF. Dashed line indicates that the GPLv2 is only compatible with the GPLv3 with the clause "or any later version".

Code licensed under several other licenses can be combined with a program under the GPL without conflict, as long as the combination of restrictions on the work as a whole does not put any additional restrictions beyond what GPL allows.[92] In addition to the regular terms of the GPL, there are additional restrictions and permissions one can apply:

  1. If a user wants to combine code licensed under different versions of GPL, then this is only allowed if the code with the earlier GPL version includes an "or any later version" statement.[93] For instance, the GPLv3-licensed GNU LibreDWG library cannot be used anymore by LibreCAD and FreeCAD who have GPLv2-only dependencies.[94]
  2. Code licensed under LGPL is permitted to be linked with any other code no matter what license that code has,[95] though the LGPL does add additional requirements for the combined work. LGPLv3 and GPLv2-only can thus commonly not be linked, as the combined Code work would add additional LGPLv3 requirements on top of the GPLv2-only licensed software. Code licensed under LGPLv2.x without the "any later version" statement can be relicensed if the whole combined work is licensed to GPLv2 or GPLv3.[96]

FSF maintains a list[97] of GPL-compatible free software licenses[98] containing many of the most common free software licenses, such as the original MIT/X license, the BSD license (in its current 3-clause form), and the Artistic License 2.0.[99]

Starting from GPLv3, it is unilaterally compatible for materials (like text and other media) under Creative Commons Attribution-ShareAlike 4.0 International License to be remixed into the GPL-licensed materials (prominently software), not vice versa, for niche use cases like game engine (GPL) with game scripts (CC BY-SA).[100][101]

David A. Wheeler has advocated that free/open source software developers use only GPL-compatible licenses, because doing otherwise makes it difficult for others to participate and contribute code.[102] As a specific example of license incompatibility, Sun Microsystems' ZFS cannot be included in the GPL-licensed Linux kernel, because it is licensed under the GPL-incompatible Common Development and Distribution License. Furthermore, ZFS is protected by patents, so distributing an independently developed GPL-ed implementation would still require Oracle's permission.[103]

A number of businesses use multi-licensing to distribute a GPL version and sell a proprietary license to companies wishing to combine the package with proprietary code, using dynamic linking or not. Examples of such companies include MySQL AB, Digia PLC (Qt framework, before 2011 from Nokia), Red Hat (Cygwin), and Riverbank Computing (PyQt). Other companies, like the Mozilla Foundation (products include Mozilla Application Suite, Mozilla Thunderbird, and Mozilla Firefox), used multi-licensing to distribute versions under the GPL and some other open-source licenses.

Text and other media Edit

It is possible to use the GPL for text documents instead of computer programs, or more generally for all kinds of media, if it is clear what constitutes the source code (defined as "the preferred form of the work for making changes in it").[104] For manuals and textbooks, though, the FSF recommends the GNU Free Documentation License (GFDL) instead, which it created for this purpose.[105] Nevertheless, the Debian developers recommended (in a resolution adopted in 2006) to license documentation for their project under the GPL, because of the incompatibility of the GFDL with the GPL (text licensed under the GFDL cannot be incorporated into GPL software).[106][107] Also, the FLOSS Manuals foundation, an organization devoted to creating manuals for free software, decided to eschew the GFDL in favor of the GPL for its texts in 2007.[108]

If the GPL is used for computer fonts, any documents or images made with such fonts might also have to be distributed under the terms of the GPL. This is not the case in countries that recognize typefaces (the appearance of fonts) as being a useful article and thus not eligible for copyright, but font files as copyrighted computer software (which can complicate font embedding, since the document could be considered 'linked' to the font; in other words, embedding a vector font in a document could force it to be released under the GPL, but a rasterized rendering of the font would not be subject to the GPL). The FSF provides an exception for cases where this is not desired.[109]

Adoption Edit

Historically, the GPL license family has been one of the most popular software licenses in the FOSS domain.[1][110][3][4][5][111]

A 1997 survey of MetaLab, then the largest free software archive, showed that the GPL accounted for about half of the software licensed therein.[110] Similarly, a 2000 survey of Red Hat Linux 7.1 found that 53% of the source code was licensed under the GPL.[3] As of 2003, about 68% of all projects and 82.1% of the open source industry certified licensed projects listed on SourceForge.net were from the GPL license family.[112] As of August 2008, the GPL family accounted for 70.9% of the 44,927 free software projects listed on Freecode.[4]

After the release of the GPLv3 in June 2007, adoption of this new GPL version was much discussed[113] and some projects decided against upgrading. For instance the Linux kernel,[33][35] MySQL,[114] BusyBox,[115] AdvFS,[116] Blender,[117][118] VLC media player,[119] and MediaWiki[120] decided against adopting GPLv3. On the other hand, in 2009, two years after the release of GPLv3, Google open-source programs office manager Chris DiBona reported that the number of open-source project licensed software that had moved from GPLv2 to GPLv3 was 50%, counting the projects hosted at Google Code.[5]

In 2011, four years after the release of the GPLv3, 6.5% of all open-source license projects are GPLv3 while 42.5% are GPLv2 according to Black Duck Software data.[121][122] Following in 2011 451 Group analyst Matthew Aslett argued in a blog post that copyleft licenses went into decline and permissive licenses increased, based on statistics from Black Duck Software.[123] Similarly, in February 2012 Jon Buys reported that among the top 50 projects on GitHub five projects were under a GPL license, including dual licensed and AGPL projects.[124]

GPL usage statistics from 2009 to 2013 was extracted from Freecode data by Walter van Holst while analyzing license proliferation.[6]

Usage of GPL family licenses in % on Freecode[6]
2009 2010 2011 2012 2013 2014-06-18[125][126]
72% 63% 61% 59% 58% approx. 54%

In August 2013, according to Black Duck Software, the website's data shows that the GPL license family is used by 54% of open-source projects, with a breakdown of the individual licenses shown in the following table.[111] However, a later study in 2013 showed that software licensed under the GPL license family has increased, and that even the data from Black Duck Software has shown a total increase of software projects licensed under GPL. The study used public information gathered from repositories of the Debian Project, and the study criticized Black Duck Software for not publishing their methodology used in collecting statistics.[127] Daniel German, Professor in the Department of Computer Science at the University of Victoria in Canada, presented a talk in 2013 about the methodological challenges in determining which are the most widely used free software licenses, and showed how he could not replicate the result from Black Duck Software.[128]

In 2015, according to Black Duck, GPLv2 lost its first position to the MIT license and is now second, the GPLv3 dropped to fourth place while the Apache license kept its third position.[1]

Usage of GPL family licenses in the FOSS domain in % according to Black Duck Software
License 2008-05-08[129] 2009-03-11[130] 2011-11-22[121] 2013-08-12[111] 2015-11-19[1] 2016-06-06[131] 2017-01-02[132] 2018-06-04[133]
GPLv2 58.69% 52.2% 42.5% 33% 23% 21% 19% 14%
GPLv3 1.64% 4.15% 6.5% 12% 9% 9% 8% 6%
LGPLv2.1 11.39% 9.84% ? 6% 5% 4% 4% 3%
LGPLv3 ? (<0.64%) 0.37% ? 3% 2% 2% 2% 1%
GPL family together 71.72% (+ <0.64%) 66.56% ? 54% 39% 36% 33% 24%

A March 2015 analysis of the GitHub repositories revealed, for the GPL license family, a usage percentage of approximately 25% among licensed projects.[134] In June 2016, an analysis of Fedora Project's packages revealed the GNU GPLv2 or later as the most popular license, and the GNU GPL family as the most popular license family (followed by the MIT, BSD, and GNU LGPL families).[135]

An analysis of whitesourcesoftware.com in April 2018 of the FOSS ecosystem saw the GPLv3 on third place (18%) and the GPLv2 on fourth place (11%), after MIT license (26%) and Apache 2.0 license (21%).[136]

Reception Edit

Legal barrier to application stores Edit

The GPL is incompatible with many application digital distribution systems, like the Mac App Store, and certain other software distribution platforms (on smartphones as well as PCs). The problem lies in the right "to make a copy for your neighbour", as this right is violated by digital rights management systems embedded within the platform to prevent copying of paid software. Even if the application is free in the application store in question, it might result in a violation of that application store's terms.[137]

There is a distinction between an app store, which sells DRM-restricted software under proprietary licenses, and the more general concept of digital distribution via some form of online software repository. Virtually all modern Unix systems and Linux distributions have application repositories, including NetBSD, FreeBSD, Ubuntu, Fedora, and Debian. These specific application repositories all contain GPL-licensed software apps, in some cases even when the core project does not permit GPL-licensed code in the base system (for instance OpenBSD[138]). In other cases, such as the Ubuntu App Store, proprietary commercial software applications and GPL-licensed applications are both available via the same system; the reason that the Mac App Store (and similar projects) is incompatible with GPL-licensed apps is not inherent in the concept of an app store, but is rather specifically due to Apple's terms-of-use requirement[137] that all apps in the store utilize Apple DRM restrictions. Ubuntu's app store does not demand any such requirement: "These terms do not limit or restrict your rights under any applicable open source software licenses."[139]

Microsoft Edit

Main article: Microsoft and open source

In 2001, Microsoft CEO Steve Ballmer referred to Linux as "a cancer that attaches itself in an intellectual property sense to everything it touches".[140][141] In response to Microsoft's attacks on the GPL, several prominent Free Software developers and advocates released a joint statement supporting the license.[142] Microsoft has released Microsoft Windows Services for UNIX, which contains GPL-licensed code. In July 2009, Microsoft itself released a body of around 20,000 lines of Linux driver code under the GPL.[143] The Hyper-V code that is part of the submitted code used open-source components licensed under the GPL and was originally statically linked to proprietary binary parts, the latter being inadmissible in GPL-licensed software.[144]

"Viral" nature Edit

The description of the GPL as "viral", when called 'General Public Virus' or 'GNU Public Virus' (GPV), dates back to a year after the GPLv1 was released.[145]

In 2001, the term received broader public attention when Craig Mundie, Microsoft Senior Vice President, described the GPL as being "viral".[146] Mundie argues that the GPL has a "viral" effect in that it only allows the conveyance of whole programs, which means programs that link to GPL libraries must themselves be under a GPL-compatible license, else they cannot be combined and distributed.

In 2006, Richard Stallman responded in an interview that Mundie's metaphor of a "virus" is wrong as software under the GPL does not "attack" or "infect" other software. Accordingly, Stallman believes that comparing the GPL to a virus is inappropriate, and that a better metaphor for software under the GPL would be a spider plant: if one takes a piece of it and puts it somewhere else, it grows there too.[147]

On the other hand, the concept of a viral nature of the GPL was taken up by others later too.[148][149] For instance, a 2008 article stated: "The GPL license is 'viral,' meaning any derivative work you create containing even the smallest portion of the previously GPL licensed software must also be licensed under the GPL license."[150]

Barrier to commercialization Edit

Main article: Business models for open-source software

The FreeBSD project has stated that "a less publicized and unintended use of the GPL is that it is very favorable to large companies that want to undercut software companies. In other words, the GPL is well suited for use as a marketing weapon, potentially reducing overall economic benefit and contributing to monopolistic behavior" and that the GPL can "present a real problem for those wishing to commercialize and profit from software."[151]

Richard Stallman wrote about the practice of selling license exceptions to free software licenses as an example of ethically acceptable commercialization practice. Selling exceptions here means that the copyright holder of a given software releases it (along with the corresponding source code) to the public under a free software license, "then lets customers pay for permission to use the same code under different terms, for instance allowing its inclusion in proprietary applications". Stallman considered selling exceptions "acceptable since the 1990s, and on occasion I've suggested it to companies. Sometimes this approach has made it possible for important programs to become free software". Although the FSF does not practice selling exceptions, a comparison with the X11 license (which is a non-copyleft free software license) is proposed for suggesting that this commercialization technique should be regarded as ethically acceptable. Releasing a given program under a non-copyleft free software license would permit embedding the code in proprietary software. Stallman comments that "either we have to conclude that it's wrong to release anything under the X11 license—a conclusion I find unacceptably extreme—or reject this implication. Using a non-copyleft license is weak, and usually an inferior choice, but it's not wrong. In other words, selling exceptions permits some embedding in proprietary software, and the X11 license permits even more embedding. If this doesn't make the X11 license unacceptable, it doesn't make selling exceptions unacceptable".[152]

Open-source criticism Edit

In 2000, developer and author Nikolai Bezroukov published an analysis and comprehensive critique of GPL's foundations and Stallman's software development model, called "Labyrinth of Software Freedom".[153][154]

Version 2 of the WTFPL (Do What The Fuck You Want To Public License) was created by Debian project leader Sam Hocevar in 2004 as a parody of the GPL.[155]

In 2005, open source software advocate Eric S. Raymond questioned the relevance of GPL then for the FOSS ecosystem, stating: "We don't need the GPL anymore. It's based on the belief that open source software is weak and needs to be protected. Open source would be succeeding faster if the GPL didn't make lots of people nervous about adopting it."[156] Richard Stallman replied: "GPL is designed to ... ensure that every user of a program gets the essential freedoms—to run it, to study and change the source code, to redistribute copies, and to publish modified versions ... [Raymond] addresses the issue in terms of different goals and values—those of 'open source,' which do not include defending software users' freedom to share and change software."[157]

In 2007, Allison Randal, who took part in the GPL draft committee, criticized the GPLv3 for being incompatible with the GPLv2[158] and for missing clarity in the formulation.[159] Similarly, Whurley prophesied in 2007 the downfall of the GPL due to the lack of focus for the developers with GPLv3 which would drive them towards permissive licenses.[160]

In 2009, David Chisnall described in an InformIT article, "The Failure of the GPL", the problems with the GPL, among them incompatibility and complexity of the license text.[161]

In 2014, dtrace developer and Joyent CTO Bryan Cantrill called the copyleft GPL a "Corporate Open Source Anti-pattern" by being "anti-collaborative" and recommended instead permissive software licenses.[162]

GPLv3 criticism Edit

Already in September 2006, in the draft process of the GPLv3, several high-profile developers of the Linux kernel, for instance Linus Torvalds, Greg Kroah-Hartman, and Andrew Morton, warned on a splitting of the FOSS community: "the release of GPLv3 portends the Balkanisation of the entire Open Source Universe upon which we rely."[31] Similarly Benjamin Mako Hill argued in 2006 on the GPLv3 draft, noting that a united, collaborating community is more important than a single license.[163]

Following the GPLv3 release in 2007, some journalists[35][121][164] and Toybox developer Rob Landley[38][39] criticized that with the introduction of the GPLv3 the split between the open source and free software community became wider than ever. As the significantly extended GPLv3 is essentially incompatible with the GPLv2,[93] compatibility between both is only given under the optional "or later" clause of the GPL, which was not taken for instance by the Linux kernel.[33] Bruce Byfield noted that before the release of the GPLv3, the GPLv2 was a unifying element between the open-source and the free software community.[121]

For the LGPLv3, GNU TLS maintainer Nikos Mavrogiannopoulos similarly argued, "If we assume that its [the LGPLv3] primary goal is to be used by free software, then it blatantly fails that",[165] after he re-licensed GNU TLS from LGPLv3 back to LGPLv2.1 due to license compatibility issues.[166]

Lawrence Rosen, attorney and computer specialist, praised in 2007 how the community using the Apache license was now able to work together with the GPL community in a compatible manner, as the problems of GPLv2 compatibility with Apache licensed software were resolved with the GPLv3. He said, "I predict that one of the biggest success stories of GPLv3 will be the realization that the entire universe of free and open-source software can thus be combined into comprehensive open source solutions for customers worldwide."[167]

In July 2013, Flask developer Armin Ronacher draws a less optimistic conclusion on the GPL compatibility in the FOSS ecosystem: "When the GPL is involved the complexities of licensing becomes a non fun version of a riddle", also noting that the conflict between Apache License 2.0 and GPLv2 still has impact on the ecosystem.[168]

See also Edit

Notes Edit

  1. ^ Sections 3a and 3b of the license
  2. ^ Sections 2b and 4 of the license
  3. ^ "GPLv3 broke "the" GPL into incompatible forks that can't share code....FSF expected universal compliance, but hijacked lifeboat clause when boat wasn't sinking...."[38][39]
  4. ^ example: if only GNU Lesser General Public License- (LGPL-) libraries, LGPL-software-components and components with permissive free software licenses are used (thus not GPL itself), then only the source code of LGPL parts has to be made available—for the developer's own self-developed software components this is not required (even when the underlying operating system used is licensed under GPL, as is the case with Linux).
  5. ^ A counterexample is the GPL'ed GNU Bison: the parsers it outputs do contain parts of itself and are therefore derivatives, which would fall under the GPL if not for a special exception granted by GNU Bison.[48]
  6. ^ See Progress Software Corporation v. MySQL AB, 195 F. Supp. 2d 328 (D. Mass. 2002), on defendant's motion for preliminary injunction.

References Edit

  1. ^ a b c d e . Black Duck Software. 19 November 2015. Archived from the original on 19 July 2016. Retrieved 19 November 2015.
  2. ^ "GPL FAQ: Does using the GPL for a program make it GNU Software?". GNU Project. Free Software Foundation.
  3. ^ a b c David A. Wheeler. "Estimating Linux's Size".
  4. ^ a b c . Archived from the original on 28 August 2008. GPL 60.5%, lGPLv2 6.9%, GPLv2 1.9% GPLv3 1.6%
  5. ^ a b c Asay, Matt (23 July 2009). . News.cnet.com. Archived from the original on 29 October 2013. Retrieved 2 September 2013.
  6. ^ a b c License proliferation: a naive quantitative analysis on lwn.net "Walter van Holst is a legal consultant at the Dutch IT consulting company mitopics... Walter instead chose to use data from a software index, namely Freecode... Walter's 2009 data set consisted of 38,674 projects... The final column in the table shows the number of projects licensed under "any version of the GPL". In addition, Walter presented pie charts that showed the proportion of projects under various common-licenses. Notable in those data sets was that, whereas in 2009 the proportion of projects licensed GPLv2-only and GPLv3 was respectively 3% and 2%, by 2013, those numbers had risen to 7% and 5%."
  7. ^ . Archived from the original on 16 May 2013. Retrieved 22 September 2006. So while the BSDs have lost energy every time a company gets involved, the GPL'ed programs gain every time a company gets involved.
  8. ^ "GNU Emacs Copying Permission Notice (1985)". GitHub. Retrieved 8 November 2015.
  9. ^ "The History of the GPL". Retrieved 24 November 2011.
  10. ^ a b c Stallman, Richard (21 April 2006). "Presentation at the second international GPLv3 conference, held in Porto Alegre".
  11. ^ "Why Upgrade to GPL Version 3 --GPLv3". Fsf.org. Retrieved 17 March 2011.
  12. ^ "FSF releases the GNU General Public License, version 3 – Free Software Foundation – working together for free software". Fsf.org. Retrieved 15 January 2011.
  13. ^ "GNU General Public License, version 1".
  14. ^ "New General Public License".
  15. ^ For the reasoning see The GNU project.
  16. ^ "GNU Library General Public License, version 2.0". Retrieved 21 November 2018.
  17. ^ "SPDX License List - Software Package Data Exchange (SPDX)". Retrieved 14 September 2021.
  18. ^ a b Stallman, Richard (25 February 2006). "Presentation in Brussels, Belgium—the first day of that year's FOSDEM conference".
  19. ^ "GPLv3 authors comment on final draft". Retrieved 4 March 2008.[permanent dead link]
    . Archived from the original on 24 June 2008. Retrieved 4 March 2008.
  20. ^ Interview with Richard Stallman 20 November 2017 at the Wayback Machine, Free Software Magazine, 23 January 2008.
  21. ^ "GPLv3: Drafting version 3 of the GNU General Public License". Free Software Foundation Europe.
  22. ^ . Archived from the original on 2 October 2008. Retrieved 31 March 2008.
  23. ^ . Archived from the original on 26 June 2008. Retrieved 31 March 2008. Showing comments in file 'gplv3-draft-1' ... found 962
  24. ^ . Archived from the original on 24 July 2008. Retrieved 31 March 2008. Showing comments in file 'gplv3-draft-1' ... found 727
    . Archived from the original on 3 July 2008. Retrieved 31 March 2008. Showing comments in file 'gplv3-draft-3' ... found 649
    . Archived from the original on 2 October 2008. Retrieved 31 March 2008. Showing comments in file 'gplv3-draft-4' ... found 298
  25. ^ "Guide to the third draft of GPLv3".
  26. ^ "Final Discussion Draft". Retrieved 4 June 2007.
  27. ^ "GPL version 3 FAQ". Retrieved 4 June 2007.
    "Fourth Discussion Draft Rationale" (PDF). Retrieved 4 June 2007.
  28. ^ Tiemann, Michael (7 June 2007). . OSI. Archived from the original on 14 August 2020. Retrieved 19 August 2013.
  29. ^ List of free-software licences on the FSF website: "We recommend that developers consider using the GNU AGPL for any software which will commonly be run over a network."
  30. ^ "GPL FAQ: Why did you decide to write the GNU Affero GPLv3 as a separate license?". GNU Project. Free Software Foundation.
  31. ^ a b c James E.J. Bottomley; Mauro Carvalho Chehab; Thomas Gleixner; Christoph Hellwig; Dave Jones; Greg Kroah-Hartman; Tony Luck; Andrew Morton; Trond Myklebust; David Woodhouse (15 September 2006). "Kernel developers' position on GPLv3 - The Dangers and Problems with GPLv3". LWN.net. Retrieved 11 March 2015. The current version (Discussion Draft 2) of GPLv3 on first reading fails the necessity test of section 1 on the grounds that there's no substantial and identified problem with GPLv2 that it is trying to solve. However, a deeper reading reveals several other problems with the current FSF draft: 5.1 DRM Clauses ... 5.2 Additional Restrictions Clause ... 5.3 Patents Provisions ... since the FSF is proposing to shift all of its projects to GPLv3 and apply pressure to every other GPL licensed project to move, we foresee the release of GPLv3 portends the Balkanisation of the entire Open Source Universe upon which we rely.
  32. ^ Petreley, Nicholas (27 September 2006). "A fight against evil or a fight for attention?". linuxjournal.com. Retrieved 11 March 2015. Second, the war between Linus Torvalds and other Kernel developers and the Free Software Foundation over GPLv3 is continuing, with Torvalds saying he's fed up with the FSF.
  33. ^ a b c d Torvalds, Linus. "COPYING". kernel.org. Retrieved 13 August 2013. [T]he only valid version of the GPL as far as the kernel is concerned is _this_ particular version of the license (ie v2, not v2.2 or v3.x or whatever), unless explicitly otherwise stated.
  34. ^ Linus Torvalds says GPL v3 violates everything that GPLv2 stood for Debconf 2014, Portland, Oregon (accessed 11 March 2015)
  35. ^ a b c Kerner, Sean Michael (8 January 2008). "Torvalds Still Keen On GPLv2". Internet News. internetnews.com. Retrieved 12 February 2015. In some ways, Linux was the project that really made the split clear between what the FSF is pushing which is very different from what open source and Linux has always been about, which is more of a technical superiority instead of a -- this religious belief in freedom," Torvalds told Zemlin. So, the GPL Version 3 reflects the FSF's goals and the GPL Version 2 pretty closely matches what I think a license should do and so right now, Version 2 is where the kernel is.
  36. ^ "GPL 3 Overview". Tech LawForum. 29 June 2007. Retrieved 2 September 2013.
  37. ^ "A Quick Guide to GPLv3". GNU Software Project. Free Software Foundation.
  38. ^ a b Landley, Rob. "Embedded Linux Conference 2013 - Toybox: Writing a New Command Line". The Linux Foundation. Archived from the original (video) on 27 October 2021. Retrieved 24 June 2016.
  39. ^ a b Landley, Rob. "Transcript of CELF 2013 Toybox talk". landley.net. Retrieved 21 August 2013.
  40. ^ Linus Torvalds (8 September 2000). "Linux-2.4.0-test8". lkml.iu.edu. Retrieved 21 November 2015. The only one of any note that I'd like to point out directly is the clarification in the COPYING file, making it clear that it's only _that_particular version of the GPL that is valid for the kernel. This should not come as any surprise, as that's the same license that has been there since 0.12 or so, but I thought I'd make that explicit
  41. ^ "GNU General Public License". Retrieved 15 June 2012.
  42. ^ a b "Selling Free Software". GNU Project. Free Software Foundation.
  43. ^ "GPL FAQ: Use GPL Tools to develop non-free programs?". GNU Project. Free Software Foundation.
  44. ^ "GPL FAQ: GPL require source posted to public". GNU Project. Free Software Foundation.
    "GPL FAQ: Unreleased modifications". GNU Project. Free Software Foundation.
    "GPL FAQ: Internal Distribution". GNU Project. Free Software Foundation.
  45. ^ a b "GPL FAQ: Port program to GNU/Linux". GNU Project. Free Software Foundation.
  46. ^ "A Quick Guide to GPLv3 – GNU Project – Free Software Foundation (FSF)". Free Software Foundation.
  47. ^ De Laat, Paul B. (December 2005). "Copyright or copyleft?". Research Policy. 34 (10): 1511–1532. doi:10.1016/j.respol.2005.07.003.
  48. ^ "Conditions for Using Bison". GNU Project. Free Software Foundation. Retrieved 11 December 2008.
  49. ^ "Reasoning behind the "preferred form" language in the GPL". LWN.net. 7 March 2011.
  50. ^ Stallman, Richard M. (9 June 2006). "Don't Let 'Intellectual Property' Twist Your Ethos".
    Moglen, Eben (22 June 2006). "Will the "Not a contract" phrase go?". Transcript. 3nd international GPLv3 conference. Barcelona.
  51. ^ Guadamuz-Gonzalez, Andres (2004). "Viral contracts or unenforceable documents? Contractual validity of copyleft licenses". European Intellectual Property Review. 26 (8): 331–339. SSRN 569101.
  52. ^ Allison Randal (14 May 2007). . Archived from the original on 15 October 2008.
  53. ^ Keith Collins (11 May 2017). "A federal court has ruled that an open-source license is an enforceable contract".
  54. ^ "SFC v. Vizio remanded back to California state courts [LWN.net]". lwn.net. Retrieved 10 June 2022.
  55. ^ "GPL FAQ: Can I modify the GPL and make a modified license?". GNU Project. Free Software Foundation.
  56. ^ "The GNU General Public License Version 3". Free Software Foundation. 29 June 2007. Retrieved 21 July 2009.
  57. ^ "GPL FAQ: Can I modify the GPL and make a modified license?". GNU Project. Free Software Foundation. 9 June 2017. Retrieved 11 July 2017.
  58. ^ "GPL FAQ: Does the GPL require that source code of modified versions be posted to the public?". GNU Project. Free Software Foundation.
  59. ^ "Frequently Asked Questions about the GNU Licenses (GPL FAQ)". GNU Project. Free Software Foundation. Retrieved 15 March 2011.
  60. ^ "Why you shouldn't use the Lesser GPL for your next library". GNU Project. Free Software Foundation. Retrieved 15 January 2011.
  61. ^ Linus Torvalds, GPL only modules, linux-kernel mailing list (17 December 2006).
  62. ^ Matt Asay, The GPL: Understanding the License that Governs Linux 6 October 2008 at the Wayback Machine, Novell Cool Solutions Feature (16 Jan 2004).
  63. ^ Lewis Galoob Toys, Inc. v. Nintendo of America, Inc., 964 F.2d 965, ¶10 (9th Cir. 21 May 1992).
  64. ^ a b Lawrence Rosen, "Derivative Works", Linux Journal (1 January 2003).
  65. ^ "Derivative Works". Rosenlaw & Einschlag. 25 May 2004.
  66. ^ Matt (29 January 2009). "Why They're Wrong: WordPress Plugins Shouldn't Have to be GPL". Webmaster-Source. Retrieved 15 January 2011.
    "Licensing". Drupal.org. Retrieved 15 January 2011.
  67. ^ "GPL FAQ: Can I apply the GPL when writing a plug-in for a nonfree program?". GNU Project. Free Software Foundation. Retrieved 15 January 2011.
  68. ^ MereAggregation "What constitutes combining two parts into one program? This is a legal question, which ultimately judges will decide. We believe that a proper criterion depends both on the mechanism of communication (exec, pipes, rpc, function calls within a shared address space, etc.) and the semantics of the communication (what kinds of information are interchanged)." on gnu.org
  69. ^ 12 Years of GPL Compliance: A Historical Perspective, by Bradley Kuhn Slide 10
  70. ^ Common Lisp, Readline and GPL, Mail on 6 November, 21:31
  71. ^ "Judge Saris defers GNU GPL Questions for Trial in MySQL vs. Progress Software". gnu.org. Retrieved 24 March 2011.
  72. ^ "JOINT STATUS REPORT, Case 2:03-cv-00294-DN, Document 1179" (PDF). IN THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF UTAH, CENTRAL DIVISION. 16 February 2018. Retrieved 25 January 2019.
  73. ^ Vaughan-Nichols, Steven J. "Last of original SCO v IBM Linux lawsuit settled". ZDNet. Retrieved 4 December 2021.
  74. ^ "Groklaw - The German GPL Order - Translated". groklaw.net.
  75. ^ Bird & Bird, A Review of German Case Law on the GNU General Public License, 17 December 2007, retrieved 1 March 2012
  76. ^ Dismissal of Wallace v. FSF. From this article on Groklaw.
  77. ^ . gnu.org. Archived from the original on 18 October 2007.
  78. ^ Welte, Harald (22 September 2006). "gpl-violations.org project prevails in court case on GPL violation by". gpl-violations.org.
  79. ^ (PDF). Archived from the original (PDF) on 26 April 2013.
  80. ^ Ewing, James (1 August 2004). "Linux on Linksys Wi-Fi Routers". Linux Journal. Retrieved 23 January 2012.
  81. ^ a b "Free Software Foundation Files Suit Against Cisco For GPL Violations" (Press release). Free Software Foundation. 11 December 2008. Retrieved 22 August 2011.
  82. ^ "FSF Settles Suit Against Cisco" (Press release). Free Software Foundation. 20 May 2009. Retrieved 22 August 2011.
  83. ^ Brockmeier, Joe (29 July 2011). "Say what? GNU Emacs violates the GPL". Network World. Retrieved 19 January 2016.
    Naughton, Edward J. (8 August 2011). . brownrudnick.com. Archived from the original on 27 January 2016.
    Soulskill (29 July 2011). "Emacs Has Been Violating the GPL Since 2009". slashdot.org.
  84. ^ Stallman, Richard (28 July 2011). "Re: Compiled files without sources????". lists.gnu.org.
  85. ^ "A federal court has ruled that the GPL is an enforceable contract". LWN.net. 15 May 2017. Retrieved 17 May 2021.
  86. ^ Robertson, Donald (11 October 2017). "Update on Artifex v. Hancom GNU GPL compliance case". Free Software Foundation. Retrieved 17 May 2021.
  87. ^ "Our lawsuit against ChessBase - Stockfish - Open Source Chess Engine". stockfishchess.org. Retrieved 22 November 2022.
  88. ^ "Statement on Fat Fritz 2 - Stockfish - Open Source Chess Engine". stockfishchess.org. Retrieved 22 November 2022.
  89. ^ "ChessBase GmbH and the Stockfish team reach an agreement and end their legal dispute - Stockfish - Open Source Chess Engine". stockfishchess.org. Retrieved 22 November 2022.
  90. ^ "Settlement (German)" (PDF). 7 November 2022. Retrieved 22 November 2022.
  91. ^ "Settlement (English)" (PDF). 7 November 2022. Retrieved 22 November 2022.
  92. ^ "The GNU General Public License v3.0". GNU Project. Free Software Foundation. Retrieved 24 March 2010.
  93. ^ a b "GPL FAQ: Is GPLv3 compatible with GPLv2?". GNU Project. Free Software Foundation. Retrieved 3 June 2014. No. Some of the requirements in GPLv3, such as the requirement to provide Installation Information, do not exist in GPLv2. As a result, the licenses are not compatible: if you tried to combine code released under both these licenses, you would violate section 6 of GPLv2. However, if code is released under GPL "version 2 or later," that is compatible with GPLv3 because GPLv3 is one of the options it permits.
  94. ^ Larabel, Michael (24 January 2013). . Phoronix. Archived from the original on 9 November 2016. Retrieved 22 August 2013. Both LibreCAD and FreeCAD both want to use LibreDWG and have patches available for supporting the DWG file format library, but can't integrate them. The programs have dependencies on the popular GPLv2 license while the Free Software Foundation will only let LibreDWG be licensed for GPLv3 use, not GPLv2.
    Prokoudine, Alexandre (27 December 2012). . libregraphicsworld.org. Archived from the original on 9 November 2016. Retrieved 23 August 2013. ... 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."
  95. ^ "GNU Lesser General Public License v2.1 – GNU Project – Free Software Foundation (FSF)". fsf.org. Retrieved 26 April 2011.
  96. ^ "GPL FAQ: How are the various GNU licenses compatible with each other?". GNU Project. Free Software Foundation. Retrieved 13 April 2011.
  97. ^ "Various licenses with comments – GPL-Compatible Free Software Licenses". FSF. Retrieved 20 April 2012.
  98. ^ "GPL FAQ: What does it mean to say that two licenses are "compatible"?". GNU Project. Free Software Foundation. Retrieved 14 April 2011.
    "GPL FAQ: What does it mean to say a license is "compatible with the GPL?"". GNU Project. Free Software Foundation. Retrieved 14 April 2011.
  99. ^ . blackducksoftware.com. Archived from the original on 14 October 2012. Retrieved 26 April 2011.
  100. ^ "Compatible Licenses".
  101. ^ "ShareAlike compatibility: GPLv3 - Creative Commons". wiki.creativecommons.org.
  102. ^ "Make Your Open Source Software GPL-Compatible. Or Else". David A. Wheeler. Retrieved 26 April 2011.
  103. ^ . Tag1 Consulting. Archived from the original on 12 June 2011.
  104. ^ "GPL FAQ: Can I use the GPL for something other than software?". GNU Project. Free Software Foundation. Retrieved 20 June 2009.
  105. ^ "GPL FAQ: Why don't you use the GPL for manuals?". GNU Project. Free Software Foundation. Retrieved 20 June 2009.
  106. ^ Srivastava, Manoj (2006). "Draft Debian Position Statement about the GNU Free Documentation License (GFDL)". Retrieved 25 September 2007. It is not possible to borrow text from a GFDL'd manual and incorporate it in any free software program whatsoever. This is not a mere license incompatibility. It's not just that the GFDL is incompatible with this or that free software license: it's that it is fundamentally incompatible with any free software license whatsoever. So if you write a new program, and you have no commitments at all about what license you want to use, saving only that it be a free license, you cannot include GFDL'd text. The GNU FDL, as it stands today, does not meet the Debian Free Software Guidelines. There are significant problems with the license, as detailed above; and, as such, we cannot accept works licensed under the GNU FDL into our distribution.
  107. ^ Debian Project: Resolution: Why the GNU Free Documentation License is not suitable for Debian. Voted February–March 2006. Retrieved 20 June 2009.
  108. ^ "License Change". FLOSS Manuals Foundation. 6 June 2007. Archived from the original on 28 February 2008. Retrieved 20 June 2009.
  109. ^ "Font Licensing". Free Software Foundation. 25 April 2005.
    "GPL FAQ: How does the GPL apply to fonts?". GNU Project. Free Software Foundation.
  110. ^ a b David A. Wheeler. "Make Your Open Source Software GPL-Compatible. Or Else".
  111. ^ a b c . Black Duck Software. 23 August 2013. Archived from the original on 19 July 2016. Retrieved 23 August 2013.
  112. ^ . Dwheeler.com. Archived from the original on 13 February 2017. Retrieved 17 November 2008. "License -> OSI: ... GNU General Public License (GPL) (32641 projects), GNU Library or Lesser General Public License (LGPL) (4889 projects" (of 45727, 82.1%)
  113. ^ Mark (8 May 2008). . socializedsoftware.com. Archived from the original on 8 December 2015. Retrieved 30 November 2015. Currently the decision to move from GPL v2 to GPL v3 is being hotly debated by many open source projects. According to Palamida, a provider of IP compliance software, there have been roughly 2489 open source projects that have moved from GPL v2 to later versions.
  114. ^ . Computer business review online. 4 January 2007. Archived from the original on 6 February 2007.
  115. ^ corbet (1 October 2006). "Busy busy busybox". lwn.net. Retrieved 21 November 2015. Since BusyBox can be found in so many embedded systems, it finds itself at the core of the GPLv3 anti-DRM debate. ... The real outcomes, however, are this: BusyBox will be GPLv2 only starting with the next release. It is generally accepted that stripping out the "or any later version" is legally defensible, and that the merging of other GPLv2-only code will force that issue in any case
    Landley, Rob (9 September 2006). "Re: Move GPLv2 vs v3 fun..." lwn.net. Retrieved 21 November 2015. Don't invent a straw man argument please. I consider licensing BusyBox under GPLv3 to be useless, unnecessary, overcomplicated, and confusing, and in addition to that it has actual downsides. 1) Useless: We're never dropping GPLv2.
  116. ^ "HP Press Release: HP Contributes Source Code to Open Source Community to Advance Adoption of Linux". www.hp.com.
  117. ^ Prokoudine, Alexandre (26 January 2012). . libregraphicsworld.org. Archived from the original on 9 November 2016. Retrieved 5 December 2015. [Blender's Toni Roosendaal:] "Blender is also still 'GPLv2 or later'. For the time being we stick to that, moving to GPL 3 has no evident benefits I know of."
  118. ^ "License - blender.org". Retrieved 17 December 2016. The source code we develop at blender.org is default being licensed as GNU GPL Version 2 or later.
  119. ^ Denis-Courmont, Rémi. "VLC media player to remain under GNU GPL version 2". videolan.org. Retrieved 21 November 2015. 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.
  120. ^ "Copyright". MediaWiki.
  121. ^ a b c d Byfield, Bruce (22 November 2011). "7 Reasons Why Free Software Is Losing Influence: Page 2". Datamation.com. Retrieved 23 August 2013. At the time, the decision seemed sensible in the face of a deadlock. But now, GPLv2 is used for 42.5% of free software, and GPLv3 for less than 6.5%, according to Black Duck Software.
  122. ^ GPL, copyleft use declining faster than ever on ITworld on 16 December 2011 by Brian Proffitt
  123. ^ Proffitt, Brian (16 December 2011). "GPL, copyleft use declining faster than ever - Data suggests a sharper rate of decline, which raises the question: why?". IT world. Retrieved 23 August 2013.
    Aslett, Matthew (15 December 2011). . the451group.com. Archived from the original on 9 December 2016. Retrieved 26 November 2015.
  124. ^ The Top Licenses on Github 4 March 2016 at the Wayback Machine on ostatic.com by Jon Buys (7 February 2012)
  125. ^ tags letter g tagged as GPL family (including misnamed variants) 21000+100+3000+2000+400 of 47985 projects on freecode (18 June 2014 frozen)
  126. ^ About Freecode 31 October 2011 at the Wayback Machine on freecode.com "The Freecode site has been moved to a static state effective 18 June 2014 due to low traffic levels and so that folks will focus on more useful endeavors than site upkeep."
  127. ^ "GPL use in Debian on the rise: study". Itwire.com. Retrieved 2 September 2013.
  128. ^ "Surveying open-source licenses". Lwn.net. Retrieved 2 September 2013.
  129. ^ Mark (8 May 2008). . socializedsoftware.com. Archived from the original on 8 December 2015. Retrieved 30 November 2015.
  130. ^ Top 20 Most Commonly Used Open Source Licenses Shaun Connolly, 11 March 2009
  131. ^ . Black Duck Software. 6 June 2016. Archived from the original on 19 July 2016. Retrieved 6 June 2016.
  132. ^ . Black Duck Software. 2 January 2017. Archived from the original on 19 July 2016. Retrieved 2 January 2017.
  133. ^ . Black Duck Software. 4 June 2018. Archived from the original on 19 July 2016. Retrieved 4 June 2018.
  134. ^ Balter, Ben (9 March 2015). "Open source license usage on GitHub.com". github.com. Retrieved 21 November 2015.
  135. ^ Anwesha Das (22 June 2016). "Software Licenses in Fedora Ecosystem". anweshadas.in. Retrieved 1 November 2016. From the above chart it is clear that the GPL family is the highest used (I had miscalculated it as MIT before). The other major licenses are MIT, BSD, the LGPL family, Artistic (for Perl packages), LPPL (fo[r] texlive packages), ASL.
  136. ^ Open Source Licensing Trends: 2017 vs. 2016 on whitesourcesoftware.com by Sivan Michaeli (12 April 2018)
  137. ^ a b "The GPL, the App Store and You" on engadget.com (2011)
  138. ^ "Copyright Policy", OpenBSD
  139. ^ "Ubuntu One : Terms and Conditions". One.ubuntu.com. 29 August 2013. Archived from the original on 25 September 2013. Retrieved 25 September 2013.
  140. ^ Newbart, Dave (1 June 2001). . Chicago Sun-Times. Archived from the original on 15 June 2001.(Internet archive link)
  141. ^ . dwheeler.com. Wheeler, David A. Archived from the original on 15 May 2013. Retrieved 6 December 2008.
  142. ^ Free Software Leaders Stand Together  – via Wikisource.
  143. ^ Clarke, Gavin (20 July 2009). "Microsoft embraces Linux cancer to sell Windows servers". The Register.
  144. ^ Clarke, Gavin (23 July 2009). "Microsoft opened Linux-driver code after 'violating' GPL". The Register.
  145. ^ Vixie, Paul (6 March 2006). . IETF Namedroppers mailing list. Archived from the original on 27 September 2007. Retrieved 29 April 2007.
    "General Public Virus". Jargon File 2.2.1. 15 December 1990. Retrieved 29 April 2007.
    Hackvän, Stig (September 1999). . Linux Journal. Archived from the original on 18 July 2011. Retrieved 29 April 2007.
    Stewart, Bill (8 October 1998). . Cypherpunks mailing list. Archived from the original on 29 May 2007. Retrieved 29 April 2007.
    Buck, Joe (10 October 2000). "Re: Using of parse tree externally". GCC mailing list. Retrieved 29 April 2007.
    Griffis, L. Adrian (15 July 2000). . Archived from the original on 30 September 2007. Retrieved 29 April 2007.
  146. ^ "Speech Transcript – Craig Mundie, The New York University Stern School of Business", Prepared Text of Remarks by Craig Mundie, Microsoft Senior Vice President, The Commercial Software Model The New York University Stern School of Business 3 May 2001
  147. ^ Poynder, Richard (21 March 2006). "The Basement Interviews: Freeing the Code". Retrieved 5 February 2010.
    Chopra, Samir; Dexter, Scott (14 August 2007). Decoding liberation: the promise of free and open source software. Routledge. p. 56. ISBN 978-0-415-97893-4.
    Williams, Sam (March 2002). Free as in Freedom: Richard Stallman's Crusade for Free Software. O'Reilly Media. ISBN 0-596-00287-4.
  148. ^ Nikolai Bezroukov (2001). . Archived from the original on 22 December 2001. Viral property stimulates proliferation of licenses and contributes to the "GPL-enforced nightmare" -- a situation when many other licenses are logically incompatible with the GPL and make life unnecessary difficult for developers working in the Linux environment (KDE is a good example here, Python is a less known example).
  149. ^ Geere, Duncan (16 December 2011). "Some rights reserved: the alternatives to copyright (Wired UK)". Wired UK. Wired.co.uk. Retrieved 30 May 2015.
    "Inoculating Your Purchase – Contractual Protection from Viral Licenses in M&A Transactions" (PDF). Friedfrank.com. Retrieved 30 May 2015.
    http://www.buddlefindlay.com/article/2013/07/01/legal-update-on-information-and-communication-technology-%E2%80%93-july-2013 16 March 2015 at the Wayback Machine
  150. ^ New Media Rights (12 September 2008). "Open Source Licensing Guide". California Western School of Law. Retrieved 28 November 2015.
  151. ^ Montague, Bruce (13 November 2013). "GPL Advantages and Disadvantages". FreeBSD. Retrieved 28 November 2015.
  152. ^ Richard Stallman (2010). On Selling Exceptions to the GNU GPL. Free Software Foundation.
  153. ^ Bezroukov, Nikolai, Labyrinth of Software Freedom - "BSD vs GPL and social aspects of free licensing debate" on softpanorama.org by Nikolai Bezroukov Accessed 23 September 2010.
  154. ^ The Scope of Open Source Licensing 9 January 2016 at the Wayback Machine - Harvard University by Josh Lerner and Jean Tirole (2002)
  155. ^ Sam Hocevar (21 September 2015). "Should I change the name of the WTFPL?". Programmers Stack Exchange (User comment). Retrieved 19 July 2016. The WTFPL is a parody of the GPL, which has a similar copyright header and list of permissions to modify (i.e. none), see for instance gnu.org/licenses/gpl-3.0.en.html. The purpose of the WTFPL wording is to give more freedom than the GPL does.
  156. ^ Biancuzzi, Federico (30 June 2005). . onlamp.com. Archived from the original on 17 April 2018. Retrieved 10 February 2015. We don't need the GPL anymore. It's based on the belief that open source software is weak and needs to be protected. Open source would be succeeding faster if the GPL didn't make lots of people nervous about adopting it.
  157. ^ . onlamp.com. 22 September 2005. Archived from the original on 17 January 2015. Retrieved 12 February 2015. ESR addresses the issue in terms of different goals and values—those of "open source," which do not include defending software users' freedom to share and change software. Perhaps he thinks the GNU GPL is not needed to achieve those goals.
  158. ^ Randal, Allison (13 April 2007). "GPLv3, Linux and GPLv2 Compatibility". radar.oreilly.com. O'Reilly Media. Retrieved 19 January 2016. You might think the FSF would have to be insane to unleash this licensing hell. ... If the license were purely a cleaned up version of the GPLv2, there would be no incompatibility, the FSF would have no agenda involved in getting projects to update to the new license, and at the same time there would be no reason for projects to object to updating. Smooth sailing.
  159. ^ Randal, Allison (14 May 2007). "GPLv3, Clarity and Simplicity". radar.oreilly.com. O'Reilly Media. Retrieved 19 January 2016. Looking at the near-finished draft, I have to say it's unlikely that they ever considered simplicity a priority, if they considered it at all. ... The language choices of an open source license can support that freedom, can empower the users and the developers. The GPLv3 doesn't.
  160. ^ Whurley (6 June 2007). . Archived from the original on 11 October 2008. Retrieved 24 June 2016. Version 3 is going to distance Richard Stallman and the Free Software Foundation from the developers that make the organization so influential to begin.
  161. ^ Chisnall, David (31 August 2009). "The Failure of the GPL". informit.com. Retrieved 24 January 2016.
  162. ^ Cantrill, Bryan (17 September 2014). "Corporate Open Source Anti-patterns". YouTube. Archived from the original on 27 October 2021. Retrieved 26 December 2015. Anti-pattern: Anti-collaborative licensing
  163. ^ Hill, Benjamin Mako (28 January 2006). "Notes on the GPLv3". linux.com. Retrieved 25 January 2016. The GPL is one thing that almost everyone in the free and open-source software communities have in common. For that reason, the revision has the potential to highlight disagreements, differences in opinion, differences in business models, and differences in tactics. ... We would be wise to remember that the potential for the GPL to hinder our ability to work together is far more dangerous than the even the most radical change textual change the FSF might suggest. ... Above all, we must remember that our community and its goals are more important than any single license -- no matter how widespread.
  164. ^ McDougall, Paul (10 July 2007). . informationweek.com. Archived from the original on 13 April 2008. Retrieved 12 February 2015. ... the latest sign of a growing schism in the open source community between business-minded developers like Torvalds and free software purists.
  165. ^ Mavrogiannopoulos, Nikos (26 March 2013). "The perils of LGPLv3". gnutls.org. Retrieved 18 November 2015. 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.
  166. ^ "GnuTLS 3.1.10: changelog". www.gnutls.org.
    Nikos Mavrogiannopoulos (18 December 2012). "gnutls is moving". Retrieved 11 December 2012.
  167. ^ Rosen, Lawrence (2007). "Comments on GPLv3". Rosenlaw.com. Retrieved 22 August 2014.
  168. ^ Ronacher, Armin (23 July 2013). "Licensing in a Post Copyright World". lucumr.pocoo.org. Retrieved 18 November 2015. The License Compatibility Clusterfuck - When the GPL is involved the complexities of licensing becomes a non fun version of a riddle. So many things to consider and so many interactions to consider. And that GPL incompatibilities are still an issue that actively effects people is something many appear to forget. For instance one would think that the incompatibility of the GPLv2 with the Apache Software License 2.0 should be a thing of the past now that everything upgrades to GPLv3, but it turns out that enough people are either stuck with GPLv2 only or do not agree with the GPLv3 that some Apache Software licensed projects are required to migrate. For instance Twitter's Bootstrap is currently migrating from ASL2.0 to MIT precisely because some people still need GPLv2 compatibility. Among those projects that were affected were Drupal, WordPress, Joomla, the MoinMoin Wiki and others. And even that case shows that people don't care that much about licenses any more as Joomla 3 just bundled bootstrap even though they were not licenses in a compatible way (GPLv2 vs ASL 2.0). The other traditional case of things not being GPL compatible is the OpenSSL project which has a license that does not go well with the GPL. That license is also still incompatible with the GPLv3. The whole ordeal is particularly interesting as some not so nice parties have started doing license trolling through GPL licenses.
    Ronacher, Armin (2009). "Are you sure you want to use the GPL?". lucumr.pocoo.org.

External links Edit

 
Wikibooks has a book on the topic of: FOSS Licensing
  • GNU General Public License (version 3)
  • GNU General Public License v2.0—This version is deprecated by the FSF but is still used by many software projects, including Linux kernel and GNU packages.
  • GNU General Public License v1.0—This version is deprecated by the FSF.
  • The Emacs General Public License, a February 1988 version, a direct predecessor of the GNU GPL
  • History of the GPL by Li-Cheng Tai, 4 July 2001
  • A Practical Guide to GPL Compliance (Covers GPLv2 and v3)—from the Software Freedom Law Center
  • Frequently Asked Questions about the GPL
  • , edited by Robert Chassell
  • List of presentation transcripts about the GPL and free software licenses 12 November 2015 at the Wayback Machine by the FSFE
  • The Labyrinth of Software Freedom BSD vs GPL and social aspects of free licensing debate, by Nikolai Bezroukov

October 20, 2023
general, public, license, simply, series, widely, used, free, software, licenses, that, guarantee, users, four, freedoms, study, share, modify, software, license, first, copyleft, general, originally, written, richard, stallman, founder, free, software, founda. The GNU General Public License GNU GPL or simply GPL is a series of widely used free software licenses that guarantee end users the four freedoms to run study share and modify the software 1 The license was the first copyleft for general use and was originally written by Richard Stallman the founder of the Free Software Foundation FSF for the GNU Project The license grants the recipients of a computer program the rights of the Free Software Definition 2 These GPL series are all copyleft licenses which means that any derivative work must be distributed under the same or equivalent license terms It is more restrictive than the Lesser General Public License and even further distinct from the more widely used permissive software licenses BSD MIT and Apache Logo for version 3 of the licenseHistorically the GPL license family has been one of the most popular software licenses in the free and open source software FOSS domain 1 3 4 5 6 Prominent free software programs licensed under the GPL include the Linux kernel and the GNU Compiler Collection GCC David A Wheeler argues that the copyleft provided by the GPL was crucial to the success of Linux based systems giving the programmers who contributed to the kernel the assurance that their work would benefit the whole world and remain free rather than being exploited by software companies that would not have to give anything back to the community 7 In 2007 the third version of the license GPLv3 was released to address some perceived problems with the second version GPLv2 which were discovered during the latter s long time usage To keep the license up to date the GPL license includes an optional any later version clause allowing users to choose between the original terms or the terms in new versions as updated by the FSF Software projects licensed with the optional or later clause include the GNU Project while the Linux kernel for instance is licensed under GPLv2 only The or any later version clause is sometimes known as a lifeboat clause since it allows combinations between different versions of GPL licensed software to maintain compatibility Contents 1 History 1 1 Version 1 1 2 Version 2 1 3 Version 3 2 Terms and conditions 2 1 Use of licensed software 2 2 Copyleft 2 3 License versus contract 3 Derivations 4 Linking and derived works 4 1 Libraries 4 1 1 Point of view dynamic and static linking violate GPL 4 1 2 Point of view static linking violates GPL but unclear as of dynamic linking 4 1 3 Point of view linking is irrelevant 4 2 Communicating and bundling with non GPL programs 5 Legal status 6 Compatibility and multi licensing 7 Text and other media 8 Adoption 9 Reception 9 1 Legal barrier to application stores 9 2 Microsoft 9 2 1 Viral nature 9 3 Barrier to commercialization 9 4 Open source criticism 9 5 GPLv3 criticism 10 See also 11 Notes 12 References 13 External linksHistory EditThe GPL was written by Richard Stallman in 1989 for use with programs released as part of the GNU project The original GPL was based on a unification of similar licenses used for early versions of GNU Emacs 1985 8 the GNU Debugger and the GNU C Compiler 9 These licenses contained similar provisions to the modern GPL but were specific to each program rendering them incompatible despite being the same license 10 Stallman s goal was to produce one license that could be used for any project thus making it possible for many projects to share code The second version of the license version 2 was released in 1991 Over the following 15 years members of the free software community became concerned over problems in the GPLv2 license that could let someone exploit GPL licensed software in ways contrary to the license s intent 11 These problems included tivoization the inclusion of GPL licensed software in hardware that refuses to run modified versions of its software compatibility issues similar to those of the Affero General Public License and patent deals between Microsoft and distributors of free and open source software which some viewed as an attempt to use patents as a weapon against the free software community Version 3 was developed to attempt to address these concerns and was officially released on 29 June 2007 12 Version 1 Edit GNU General Public License version 1Published25 February 1989Websitewww wbr gnu wbr org wbr licenses wbr old licenses wbr gpl 1 wbr 0 wbr htmlVersion 1 of the GNU GPL 13 released on 25 February 1989 14 prevented what were then the two main ways that software distributors restricted the freedoms that define free software The first problem was that distributors may publish only binary files that are executable but not readable or modifiable by humans To prevent this GPLv1 stated that copying and distributing copies of any portion of the program must also make the human readable source code available under the same licensing terms a The second problem was that distributors might add restrictions either to the license or by combining the software with other software that had other restrictions on distribution The union of two sets of restrictions would apply to the combined work thus adding unacceptable restrictions To prevent this GPLv1 stated that modified versions as a whole had to be distributed under the terms of GPLv1 b Therefore software distributed under the terms of GPLv1 could be combined with software under more permissive terms as this would not change the terms under which the whole could be distributed However software distributed under GPLv1 could not be combined with software distributed under a more restrictive license as this would conflict with the requirement that the whole be distributable under the terms of GPLv1 Version 2 Edit GNU General Public License version 2PublishedJune 1991Websitewww wbr gnu wbr org wbr licenses wbr old licenses wbr gpl 2 wbr 0 wbr htmlAccording to Richard Stallman the major change in GPLv2 was the Liberty or Death clause as he calls it 10 Section 7 The section says that licensees may distribute a GPL covered work only if they can satisfy all of the license s obligations despite any other legal obligations they might have In other words the obligations of the license may not be severed due to conflicting obligations This provision is intended to discourage any party from using a patent infringement claim or other litigation to impair users freedom under the license 10 By 1990 it was becoming apparent that a less restrictive license would be strategically useful for the C library and for software libraries that essentially did the job of existing proprietary ones 15 when version 2 of the GPL GPLv2 was released in June 1991 therefore a second license the GNU Library General Public License was introduced at the same time and numbered with version 2 to show that both were complementary 16 The version numbers diverged in 1999 when version 2 1 of the LGPL was released which renamed it the GNU Lesser General Public License to reflect its place in the philosophy The GPLv2 was also modified to refer to the new name of the LGPL but its version number remained the same resulting in the original GPLv2 not being recognised by the Software Package Data Exchange SPDX 17 failed verification The license includes instructions to specify version 2 of the License or at your option any later version to allow the flexible optional use of either version 2 or 3 but some developers change this to specify version 2 only Version 3 Edit GNU General Public License version 3Published29 June 2007Websitewww wbr gnu wbr org wbr licenses wbr gpl 3 wbr 0 wbr htmlIn late 2005 the Free Software Foundation FSF announced work on version 3 of the GPL GPLv3 On 16 January 2006 the first discussion draft of GPLv3 was published and the public consultation began The public consultation was originally planned for nine to fifteen months but finally stretched to eighteen months with four drafts being published The official GPLv3 was released by the FSF on 29 June 2007 GPLv3 was written by Richard Stallman with legal counsel from Eben Moglen and Richard Fontana from the Software Freedom Law Center 18 19 According to Stallman the most important changes were in relation to software patents free software license compatibility the definition of source code and hardware restrictions on software modifications such as tivoization 18 20 Other changes related to internationalization how license violations are handled and how additional permissions could be granted by the copyright holder The concept of software propagation as a term for the copying and duplication of software was explicitly defined The public consultation process was coordinated by the Free Software Foundation with assistance from Software Freedom Law Center Free Software Foundation Europe 21 and other free software groups Comments were collected from the public via the gplv3 fsf org web portal 22 using purpose written software called stet During the public consultation process 962 comments were submitted for the first draft 23 By the end of the comment period a total of 2 636 comments had been submitted 24 The third draft was released on 28 March 2007 25 This draft included language intended to prevent patent related agreements such as the controversial Microsoft Novell patent agreement and restricted the anti tivoization clauses to a legal definition of a user and a consumer product It also explicitly removed the section on Geographical Limitations whose probable removal had been announced at the launch of the public consultation nbsp Richard Stallman at the launch of the first draft of the GNU GPLv3 at MIT Cambridge Massachusetts United States To his right is Columbia Law Professor Eben Moglen chairman of the Software Freedom Law Center The fourth discussion draft 26 which was the last was released on 31 May 2007 It introduced Apache License version 2 0 compatibility prior versions are incompatible clarified the role of outside contractors and made an exception to avoid the perceived problems of a Microsoft Novell style agreement saying in Section 11 paragraph 6 that You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software under which you make payment to the third party based on the extent of your activity of conveying the work and under which the third party grants to any of the parties who would receive the covered work from you a discriminatory patent license This aimed to make future such deals ineffective The license was also meant to cause Microsoft to extend the patent licenses it granted to Novell customers for the use of GPLv3 software to all users of that GPLv3 software this was possible only if Microsoft was legally a conveyor of the GPLv3 software 27 Early drafts of GPLv3 also let licensors add an Affero like requirement that would have plugged the ASP loophole in the GPL 28 29 As there were concerns expressed about the administrative costs of checking code for this additional requirement it was decided to keep the GPL and the Affero license separated 30 Others notably some high profile Linux kernel developers such as Linus Torvalds Greg Kroah Hartman and Andrew Morton commented to the mass media and made public statements about their objections to parts of discussion drafts 1 and 2 31 The kernel developers referred to GPLv3 draft clauses regarding DRM Tivoization patents and additional restrictions and warned of a Balkanisation of the Open Source Universe 31 32 Linus Torvalds who decided not to adopt the GPLv3 for the Linux kernel 33 reiterated his criticism several years later 34 35 GPLv3 improved compatibility with several free software licenses such as the Apache License version 2 0 and the GNU Affero General Public License which GPLv2 could not be combined with 36 However GPLv3 software could only be combined and share code with GPLv2 software if the GPLv2 license used had the optional or later clause and the software was upgraded to GPLv3 While the GPLv2 or any later version clause is considered by FSF as the most common form of licensing GPLv2 software 37 Toybox developer Rob Landley described it as a lifeboat clause c Software projects licensed with the optional or later clause include the GNU Project citation needed while a prominent example without the clause is the Linux kernel 33 40 The final version of the license text was published on 29 June 2007 41 Terms and conditions EditThe terms and conditions of the GPL must be made available to anybody receiving a copy of the work that has a GPL applied to it the licensee Any licensee who adheres to the terms and conditions is given permission to modify the work as well as to copy and redistribute the work or any derivative version The licensee is allowed to charge a fee for this service or do this free of charge This latter point distinguishes the GPL from software licenses that prohibit commercial redistribution The FSF argues that free software should not place restrictions on commercial use 42 and the GPL explicitly states that GPL works may be sold at any price The GPL additionally states that a distributor may not impose further restrictions on the rights granted by the GPL This forbids activities such as distributing the software under a non disclosure agreement or contract The fourth section for version 2 of the license and the seventh section of version 3 require that programs distributed as pre compiled binaries be accompanied by a copy of the source code a written offer to distribute the source code via the same mechanism as the pre compiled binary or the written offer to obtain the source code that the user got when they received the pre compiled binary under the GPL The second section of version 2 and the fifth section of version 3 also require giving all recipients a copy of this License along with the Program Version 3 of the license allows making the source code available in additional ways in fulfillment of the seventh section These include downloading source code from an adjacent network server or by peer to peer transmission provided that is how the compiled code was available and there are clear directions on where to find the source code The FSF does not hold the copyright for a work released under the GPL unless an author explicitly assigns copyrights to the FSF which seldom happens except for programs that are part of the GNU project Only the individual copyright holders have the authority to sue when a license violation is suspected nbsp Printed GPL statements for consumer entertainment devices which incorporate GPL componentsUse of licensed software Edit Software under the GPL may be run for all purposes including commercial purposes and even as a tool for creating proprietary software such as when using GPL licensed compilers 43 Users or companies who distribute GPL licensed works e g software may charge a fee for copies or give them free of charge This distinguishes the GPL from shareware software licenses that allow copying for personal use but prohibit the commercial distribution or proprietary licenses where copying is prohibited by copyright law The FSF argues that freedom respecting free software should also not restrict commercial use and distribution including redistribution 42 In purely private or internal use with no sales and no distribution the software code may be modified and parts reused without requiring the source code to be released For sales or distribution the entire source code needs to be made available to end users including any code changes and additions in that case copyleft is applied to ensure that end users retain the freedoms defined above 44 However software running as an application program under a GPL licensed operating system such as Linux is not required to be licensed under GPL or to be distributed with source code availability the licensing depends only on the used libraries and software components and not on the underlying platform 45 For example if a program consists only of original source code or is combined with source code from other software components d then the custom software components need not be licensed under GPL and need not make their source code available even if the underlying operating system used is licensed under the GPL applications running on it are not considered derivative works 45 Only if GPLed parts are used in a program and the program is distributed then all other source code of the program needs to be made available under the same license terms The GNU Lesser General Public License LGPL was created to have a weaker copyleft than the GPL in that it does not require custom developed source code distinct from the LGPL ed parts to be made available under the same license terms The fifth section of version 3 states that no GPL licensed code shall be considered an effective technical protection measure as defined by Article 11 of the WIPO Copyright Treaty and that those who convey the work waive all legal power to prohibit circumvention of the technical protection measure to the extent such circumvention is effected by exercising rights under this License with respect to the covered work This means that users cannot be held liable for circumventing DRM implemented using GPLv3 licensed code under laws such as the U S Digital Millennium Copyright Act DMCA 46 Copyleft Edit Main article Copyleft The distribution rights granted by the GPL for modified versions of the work are not unconditional When someone distributes a GPL ed work plus their own modifications the requirements for distributing the whole work cannot be any greater than the requirements that are in the GPL This requirement is known as copyleft It earns its legal power from the use of copyright on software programs Because a GPL work is copyrighted a licensee has no right to redistribute it not even in modified form barring fair use except under the terms of the license One is only required to adhere to the terms of the GPL if one wishes to exercise rights normally restricted by copyright law such as redistribution Conversely if one distributes copies of the work without abiding by the terms of the GPL for instance by keeping the source code secret they can be sued by the original author under copyright law Copyright law has historically been used to prevent distribution of work by parties not authorized by the creator Copyleft uses the same copyright laws to accomplish a very different goal It grants rights to distribution to all parties insofar as they provide the same rights to subsequent ones and they to the next etc In this way the GPL and other copyleft licenses attempt to enforce libre access to the work and all derivatives 47 Many distributors of GPL ed programs bundle the source code with the executables An alternative method of satisfying the copyleft is to provide a written offer to provide the source code on a physical medium such as a CD upon request In practice many GPL ed programs are distributed over the Internet and the source code is made available over FTP or HTTP For Internet distribution this complies with the license Copyleft applies only when a person seeks to redistribute the program Developers may make private modified versions with no obligation to divulge the modifications as long as they do not distribute the modified software to anyone else Copyleft applies only to the software and not to its output unless that output is itself a derivative work of the program e For example a public web portal running a modified derivative of a GPL ed content management system is not required to distribute its changes to the underlying software because the modified web portal is not being redistributed but rather hosted and also because the web portal output is also not a derivative work of the GPL ed content management system There has been debate on whether it is a violation of the GPL to release the source code in obfuscated form such as in cases in which the author is less willing to make the source code available The consensus was that while unethical it was not considered a violation The issue was clarified when the license was altered with v2 to require that the preferred version of the source code be made available 49 License versus contract Edit The GPL was designed as a license rather than a contract 50 In some Common Law jurisdictions the legal distinction between a license and a contract is an important one contracts are enforceable by contract law whereas licenses are enforced under copyright law However this distinction is not useful in the many jurisdictions where there are no differences between contracts and licenses such as Civil Law systems 51 Those who do not accept the GPL s terms and conditions do not have permission under copyright law to copy or distribute GPL licensed software or derivative works However if they do not redistribute the GPL ed program they may still use the software within their organization however they like and works including programs constructed by the use of the program are not required to be covered by this license Software developer Allison Randal argued that the GPLv3 as a license is unnecessarily confusing for lay readers and could be simplified while retaining the same conditions and legal force 52 In April 2017 a US federal court ruled that an open source license is an enforceable contract 53 In October 2021 SFC sued Vizio over breach of contract as an end user to request source code to Vizio s TVs a federal judge has ruled in the interim that the GPL is an enforceable contract by end users as well as a license for copyright holders 54 Derivations EditThe text of the GPL is itself copyrighted and the copyright is held by the Free Software Foundation The FSF permits people to create new licenses based on the GPL as long as the derived licenses do not use the GPL preamble without permission This is discouraged however since such a license might be incompatible with the GPL 55 and causes a perceived license proliferation Other licenses created by the GNU project include the GNU Lesser General Public License GNU Free Documentation License and Affero General Public License The text of the GPL is not itself under the GPL The license s copyright disallows modification of the license Copying and distributing the license is allowed since the GPL requires recipients to get a copy of this License along with the Program 56 According to the GPL FAQ anyone can make a new license using a modified version of the GPL as long as they use a different name for the license do not mention GNU and remove the preamble though the preamble can be used in a modified license if permission to use it is obtained from the Free Software Foundation FSF 57 Linking and derived works EditLibraries Edit According to the FSF The GPL does not require you to release your modified version or any part of it You are free to make modifications and use them privately without ever releasing them 58 However if one releases a GPL licensed entity to the public there is an issue regarding linking namely whether a proprietary program that uses a GPL library is in violation of the GPL This key dispute is whether non GPL software can legally statically link or dynamically link to GPL libraries Different opinions exist on this issue The GPL is clear in requiring that all derivative works of code under the GPL must themselves be under the GPL Ambiguity arises with regards to using GPL libraries and bundling GPL software into a larger package perhaps mixed into a binary via static linking This is ultimately a question not of the GPL per se but of how copyright law defines derivative works The following points of view exist Point of view dynamic and static linking violate GPL Edit The Free Software Foundation which holds the copyright of several notable GPL licensed software products and of the license text itself asserts that an executable that uses a dynamically linked library is indeed a derivative work This does not however apply to separate programs communicating with one another 59 The Free Software Foundation also created the LGPL which is nearly identical to the GPL but with additional permissions to allow linking for the purposes of using the library Richard Stallman and the FSF specifically encourage library writers to license under the GPL so that proprietary programs cannot use the libraries in an effort to protect the free software world by giving it more tools than the proprietary world 60 Point of view static linking violates GPL but unclear as of dynamic linking Edit Some people believe that while static linking produces derivative works it is not clear whether an executable that dynamically links to a GPL code should be considered a derivative work see weak copyleft Linux author Linus Torvalds agrees that dynamic linking can create derived works but disagrees over the circumstances 61 A Novell lawyer has written that dynamic linking not being derivative makes sense but is not clear cut and that evidence for good intentioned dynamic linking can be seen by the existence of proprietary Linux kernel drivers 62 In Galoob v Nintendo the United States Ninth Circuit Court of Appeals defined a derivative work as having form or permanence and noted that the infringing work must incorporate a portion of the copyrighted work in some form 63 but there have been no clear court decisions to resolve this particular conflict Point of view linking is irrelevant Edit According to an article in the Linux Journal Lawrence Rosen a one time Open Source Initiative general counsel argues that the method of linking is mostly irrelevant to the question about whether a piece of software is a derivative work more important is the question about whether the software was intended to interface with client software and or libraries 64 He states The primary indication of whether a new program is a derivative work is whether the source code of the original program was used in a copy paste sense modified translated or otherwise changed in any way to create the new program If not then I would argue that it is not a derivative work 64 and lists numerous other points regarding intent bundling and linkage mechanism He further argues on his firm s website 65 that such market based factors are more important than the linking technique There is also the specific issue of whether a plugin or module such as the NVidia or ATI graphics card kernel modules must also be GPL if it could reasonably be considered its own work This point of view suggests that reasonably separate plugins or plugins for software designed to use plugins could be licensed under an arbitrary license if the work is GPLv2 Of particular interest is the GPLv2 paragraph You may modify your copy or copies of the Program or any portion of it thus forming a work based on the Program and copy and distribute such modifications or work under the terms of Section 1 above provided that you also meet all of these conditions b You must cause any work that you distribute or publish that in whole or in part contains or is derived from the Program or any part thereof to be licensed as a whole at no charge to all third parties under the terms of this License These requirements apply to the modified work as a whole If identifiable sections of that work are not derived from the Program and can be reasonably considered independent and separate works in themselves then this License and its terms do not apply to those sections when you distribute them as separate works But when you distribute the same sections as part of a whole which is a work based on the Program the distribution of the whole must be on the terms of this License whose permissions for other licensees extend to the entire whole and thus to each and every part regardless of who wrote it The GPLv3 has a different clause You may convey a work based on the Program or the modifications to produce it from the Program in the form of source code under the terms of Section 4 provided that you also meet all of these conditions c You must license the entire work as a whole under this License to anyone who comes into possession of a copy This License will therefore apply along with any applicable Section 7 additional terms to the whole of the work and all its parts regardless of how they are packaged This License gives no permission to license the work in any other way but it does not invalidate such permission if you have separately received it A compilation of a covered work with other separate and independent works which are not by their nature extensions of the covered work and which are not combined with it such as to form a larger program in or on a volume of a storage or distribution medium is called an aggregate if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation s users beyond what the individual works permit Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate As a case study some supposedly proprietary plugins and themes skins for GPLv2 CMS software such as Drupal and WordPress have come under fire with both sides of the argument taken 66 The FSF differentiates on how the plugin is being invoked If the plugin is invoked through dynamic linkage and it performs function calls to the GPL program then it is most likely a derivative work 67 Communicating and bundling with non GPL programs Edit The mere act of communicating with other programs does not by itself require all software to be GPL nor does distributing GPL software with non GPL software However minor conditions must be followed that ensures the rights of GPL software are not restricted The following is a quote from the gnu org GPL FAQ which describes to what extent software is allowed to communicate with and be bundled with GPL programs 68 What is the difference between an aggregate and other kinds of modified versions An aggregate consists of a number of separate programs distributed together on the same CD ROM or other media The GPL permits you to create and distribute an aggregate even when the licenses of the other software are non free or GPL incompatible The only condition is that you cannot release the aggregate under a license that prohibits users from exercising rights that each program s individual license would grant them Where s the line between two separate programs and one program with two parts This is a legal question which ultimately judges will decide We believe that a proper criterion depends both on the mechanism of communication exec pipes rpc function calls within a shared address space etc and the semantics of the communication what kinds of information are interchanged If the modules are included in the same executable file they are definitely combined in one program If modules are designed to run linked together in a shared address space that almost surely means combining them into one program By contrast pipes sockets and command line arguments are communication mechanisms normally used between two separate programs So when they are used for communication the modules normally are separate programs But if the semantics of the communication are intimate enough exchanging complex internal data structures that too could be a basis to consider the two parts as combined into a larger program The FSF thus draws the line between library and other program via 1 complexity and intimacy of information exchange and 2 mechanism rather than semantics but resigns that the question is not clear cut and that in complex situations case law will decide Legal status EditSee also SCO Linux controversies and SCO v IBM The first known violation of the GPL was in 1989 when NeXT extended the GCC compiler to support Objective C but did not publicly release the changes 69 After an inquiry they created a public patch There was no lawsuit filed for this violation 70 In 2002 MySQL AB sued Progress NuSphere for copyright and trademark infringement in United States district court NuSphere had allegedly violated MySQL s copyright by linking MySQL s GPL ed code with NuSphere Gemini table without complying with the license After a preliminary hearing before Judge Patti Saris on 27 February 2002 the parties entered settlement talks and eventually settled f After the hearing FSF commented that Judge Saris made clear that she sees the GNU GPL to be an enforceable and binding license 71 In August 2003 the SCO Group stated that they believed the GPL to have no legal validity and that they intended to pursue lawsuits over sections of code supposedly copied from SCO Unix into the Linux kernel This was a problematic stand for them as they had distributed Linux and other GPL ed code in their Caldera OpenLinux distribution and there is little evidence that they had any legal right to do so except under the terms of the GPL citation needed In February 2018 after federal circuit court judgement appeal and the case being partially remanded to the circuit court the parties restated their remaining claims and provided a plan to move toward final judgement 72 The remaining claims revolved around Project Monterey and were finally settled in November 2021 by IBM paying 14 25 million to the TSG previously SCO bankruptcy trustee 73 In April 2004 the netfilter iptables project was granted a preliminary injunction against Sitecom Germany by Munich District Court after Sitecom refused to desist from distributing Netfilter s GPL ed software in violation of the terms of the GPL Harald Welte of Netfilter was represented by ifrOSS co founder Till Jaeger In July 2004 the German court confirmed this injunction as a final ruling against Sitecom 74 The court s justification was that Defendant has infringed on the copyright of plaintiff by offering the software netfilter iptables for download and by advertising its distribution without adhering to the license conditions of the GPL Said actions would only be permissible if the defendant had a license grant This is independent of the questions whether the licensing conditions of the GPL have been effectively agreed upon between plaintiff and defendant or not If the GPL were not agreed upon by the parties defendant would notwithstanding lack the necessary rights to copy distribute and make the software netfilter iptables publicly available This exactly mirrored the predictions given previously by the FSF s Eben Moglen This ruling was important because it was the first time that a court had confirmed that violating terms of the GPL could be a copyright violation and established jurisprudence as to the enforceability of the GPLv2 under German law 75 In May 2005 Daniel Wallace filed suit against the Free Software Foundation in the Southern District of Indiana contending that the GPL is an illegal attempt to fix prices at zero The suit was dismissed in March 2006 on the grounds that Wallace had failed to state a valid antitrust claim the court noted that the GPL encourages rather than discourages free competition and the distribution of computer operating systems the benefits of which directly pass to consumers 76 Wallace was denied the possibility of further amending his complaint and was ordered to pay the FSF s legal expenses On 8 September 2005 the Seoul Central District Court ruled that the GPL was not material to a case dealing with trade secrets derived from GPL licensed work 77 Defendants argued that since it is impossible to maintain trade secrets while being compliant with GPL and distributing the work they are not in breach of trade secrets This argument was considered without ground On 6 September 2006 the gpl violations org project prevailed in court litigation against D Link Germany GmbH regarding D Link s copyright infringing use of parts of the Linux kernel in storage devices they distributed 78 The judgment stated that the GPL is valid legally binding and stands in German court 79 In late 2007 the BusyBox developers and the Software Freedom Law Center embarked upon a program to gain GPL compliance from distributors of BusyBox in embedded systems suing those who would not comply These were claimed to be the first US uses of courts for enforcement of GPL obligations See BusyBox GPL lawsuits On 11 December 2008 the Free Software Foundation sued Cisco Systems Inc for copyright violations by its Linksys division of the FSF s GPL licensed coreutils readline Parted Wget GNU Compiler Collection binutils and GNU Debugger software packages which Linksys distributes in the Linux firmware 80 of its WRT54G wireless routers as well as numerous other devices including DSL and Cable modems Network Attached Storage devices Voice Over IP gateways virtual private network devices and a home theater media player device 81 After six years of repeated complaints to Cisco by the FSF claims by Cisco that they would correct or were correcting their compliance problems not providing complete copies of all source code and their modifications of repeated new violations being discovered and reported with more products and lack of action by Linksys a process described on the FSF blog as a five years running game of Whack a Mole 81 the FSF took them to court Cisco settled the case six months later by agreeing to appoint a Free Software Director for Linksys to ensure compliance to notify previous recipients of Linksys products containing FSF programs of their rights under the GPL to make source code of FSF programs freely available on its website and to make a monetary contribution to the FSF 82 In 2011 it was noticed that GNU Emacs had been accidentally releasing some binaries without corresponding source code for two years in opposition to the intended spirit of the GPL resulting in a copyright violation 83 Richard Stallman described this incident as a very bad mistake 84 which was promptly fixed The FSF did not sue any downstream redistributors who also unknowingly violated the GPL by distributing these binaries In 2017 Artifex the maker of Ghostscript sued Hancom the maker of an office suite which included Ghostscript Artifex offers two licenses for Ghostscript one is the Affero GPL License and the other is a commercial license Hancom did not acquire a commercial license from Artifex nor did it release its office suite as free software Artifex sued Hancom in US District Court and made two claims First Hancom s use of Ghostscript was a violation of copyright and second Hancom s use of Ghostscript was a license violation Judge Jacqueline Scott Corley found the GPL license was an enforceable contract and Hancom was in breach of contract 85 86 On 20 July 2021 the developers of the open source Stockfish chess engine sued ChessBase the creator of chess software for violating the GPLv3 license 87 It was claimed that Chessbase had made only slight modifications to the Stockfish code and sold the new engines Fat Fritz 2 and Houdini 6 to their customers 88 Additionally Fat Fritz 2 was marketed as if it was an innovative engine ChessBase had infringed on the license by not distributing these products as Free Software in accordance with the GPL A year later on 7 November 2022 both parties reached an agreement and ended the dispute In the near future ChessBase will no longer sell products containing Stockfish code while informing their customers of this fact with an appropriate notice on their web pages However one year later Chessbase s license would be reinstated Stockfish did not seek damages or financial compensation 89 90 91 Compatibility and multi licensing Edit nbsp Quick guide of license compatibility with GPLv3 according to the FSF Dashed line indicates that the GPLv2 is only compatible with the GPLv3 with the clause or any later version Code licensed under several other licenses can be combined with a program under the GPL without conflict as long as the combination of restrictions on the work as a whole does not put any additional restrictions beyond what GPL allows 92 In addition to the regular terms of the GPL there are additional restrictions and permissions one can apply If a user wants to combine code licensed under different versions of GPL then this is only allowed if the code with the earlier GPL version includes an or any later version statement 93 For instance the GPLv3 licensed GNU LibreDWG library cannot be used anymore by LibreCAD and FreeCAD who have GPLv2 only dependencies 94 Code licensed under LGPL is permitted to be linked with any other code no matter what license that code has 95 though the LGPL does add additional requirements for the combined work LGPLv3 and GPLv2 only can thus commonly not be linked as the combined Code work would add additional LGPLv3 requirements on top of the GPLv2 only licensed software Code licensed under LGPLv2 x without the any later version statement can be relicensed if the whole combined work is licensed to GPLv2 or GPLv3 96 FSF maintains a list 97 of GPL compatible free software licenses 98 containing many of the most common free software licenses such as the original MIT X license the BSD license in its current 3 clause form and the Artistic License 2 0 99 Starting from GPLv3 it is unilaterally compatible for materials like text and other media under Creative Commons Attribution ShareAlike 4 0 International License to be remixed into the GPL licensed materials prominently software not vice versa for niche use cases like game engine GPL with game scripts CC BY SA 100 101 David A Wheeler has advocated that free open source software developers use only GPL compatible licenses because doing otherwise makes it difficult for others to participate and contribute code 102 As a specific example of license incompatibility Sun Microsystems ZFS cannot be included in the GPL licensed Linux kernel because it is licensed under the GPL incompatible Common Development and Distribution License Furthermore ZFS is protected by patents so distributing an independently developed GPL ed implementation would still require Oracle s permission 103 A number of businesses use multi licensing to distribute a GPL version and sell a proprietary license to companies wishing to combine the package with proprietary code using dynamic linking or not Examples of such companies include MySQL AB Digia PLC Qt framework before 2011 from Nokia Red Hat Cygwin and Riverbank Computing PyQt Other companies like the Mozilla Foundation products include Mozilla Application Suite Mozilla Thunderbird and Mozilla Firefox used multi licensing to distribute versions under the GPL and some other open source licenses Text and other media EditIt is possible to use the GPL for text documents instead of computer programs or more generally for all kinds of media if it is clear what constitutes the source code defined as the preferred form of the work for making changes in it 104 For manuals and textbooks though the FSF recommends the GNU Free Documentation License GFDL instead which it created for this purpose 105 Nevertheless the Debian developers recommended in a resolution adopted in 2006 to license documentation for their project under the GPL because of the incompatibility of the GFDL with the GPL text licensed under the GFDL cannot be incorporated into GPL software 106 107 Also the FLOSS Manuals foundation an organization devoted to creating manuals for free software decided to eschew the GFDL in favor of the GPL for its texts in 2007 108 If the GPL is used for computer fonts any documents or images made with such fonts might also have to be distributed under the terms of the GPL This is not the case in countries that recognize typefaces the appearance of fonts as being a useful article and thus not eligible for copyright but font files as copyrighted computer software which can complicate font embedding since the document could be considered linked to the font in other words embedding a vector font in a document could force it to be released under the GPL but a rasterized rendering of the font would not be subject to the GPL The FSF provides an exception for cases where this is not desired 109 Adoption EditHistorically the GPL license family has been one of the most popular software licenses in the FOSS domain 1 110 3 4 5 111 A 1997 survey of MetaLab then the largest free software archive showed that the GPL accounted for about half of the software licensed therein 110 Similarly a 2000 survey of Red Hat Linux 7 1 found that 53 of the source code was licensed under the GPL 3 As of 2003 update about 68 of all projects and 82 1 of the open source industry certified licensed projects listed on SourceForge net were from the GPL license family 112 As of August 2008 update the GPL family accounted for 70 9 of the 44 927 free software projects listed on Freecode 4 After the release of the GPLv3 in June 2007 adoption of this new GPL version was much discussed 113 and some projects decided against upgrading For instance the Linux kernel 33 35 MySQL 114 BusyBox 115 AdvFS 116 Blender 117 118 VLC media player 119 and MediaWiki 120 decided against adopting GPLv3 On the other hand in 2009 two years after the release of GPLv3 Google open source programs office manager Chris DiBona reported that the number of open source project licensed software that had moved from GPLv2 to GPLv3 was 50 counting the projects hosted at Google Code 5 In 2011 four years after the release of the GPLv3 6 5 of all open source license projects are GPLv3 while 42 5 are GPLv2 according to Black Duck Software data 121 122 Following in 2011 451 Group analyst Matthew Aslett argued in a blog post that copyleft licenses went into decline and permissive licenses increased based on statistics from Black Duck Software 123 Similarly in February 2012 Jon Buys reported that among the top 50 projects on GitHub five projects were under a GPL license including dual licensed and AGPL projects 124 GPL usage statistics from 2009 to 2013 was extracted from Freecode data by Walter van Holst while analyzing license proliferation 6 Usage of GPL family licenses in on Freecode 6 2009 2010 2011 2012 2013 2014 06 18 125 126 72 63 61 59 58 approx 54 In August 2013 according to Black Duck Software the website s data shows that the GPL license family is used by 54 of open source projects with a breakdown of the individual licenses shown in the following table 111 However a later study in 2013 showed that software licensed under the GPL license family has increased and that even the data from Black Duck Software has shown a total increase of software projects licensed under GPL The study used public information gathered from repositories of the Debian Project and the study criticized Black Duck Software for not publishing their methodology used in collecting statistics 127 Daniel German Professor in the Department of Computer Science at the University of Victoria in Canada presented a talk in 2013 about the methodological challenges in determining which are the most widely used free software licenses and showed how he could not replicate the result from Black Duck Software 128 In 2015 according to Black Duck GPLv2 lost its first position to the MIT license and is now second the GPLv3 dropped to fourth place while the Apache license kept its third position 1 Usage of GPL family licenses in the FOSS domain in according to Black Duck Software License 2008 05 08 129 2009 03 11 130 2011 11 22 121 2013 08 12 111 2015 11 19 1 2016 06 06 131 2017 01 02 132 2018 06 04 133 GPLv2 58 69 52 2 42 5 33 23 21 19 14 GPLv3 1 64 4 15 6 5 12 9 9 8 6 LGPLv2 1 11 39 9 84 6 5 4 4 3 LGPLv3 lt 0 64 0 37 3 2 2 2 1 GPL family together 71 72 lt 0 64 66 56 54 39 36 33 24 A March 2015 analysis of the GitHub repositories revealed for the GPL license family a usage percentage of approximately 25 among licensed projects 134 In June 2016 an analysis of Fedora Project s packages revealed the GNU GPLv2 or later as the most popular license and the GNU GPL family as the most popular license family followed by the MIT BSD and GNU LGPL families 135 An analysis of whitesourcesoftware com in April 2018 of the FOSS ecosystem saw the GPLv3 on third place 18 and the GPLv2 on fourth place 11 after MIT license 26 and Apache 2 0 license 21 136 Reception EditLegal barrier to application stores Edit The GPL is incompatible with many application digital distribution systems like the Mac App Store and certain other software distribution platforms on smartphones as well as PCs The problem lies in the right to make a copy for your neighbour as this right is violated by digital rights management systems embedded within the platform to prevent copying of paid software Even if the application is free in the application store in question it might result in a violation of that application store s terms 137 There is a distinction between an app store which sells DRM restricted software under proprietary licenses and the more general concept of digital distribution via some form of online software repository Virtually all modern Unix systems and Linux distributions have application repositories including NetBSD FreeBSD Ubuntu Fedora and Debian These specific application repositories all contain GPL licensed software apps in some cases even when the core project does not permit GPL licensed code in the base system for instance OpenBSD 138 In other cases such as the Ubuntu App Store proprietary commercial software applications and GPL licensed applications are both available via the same system the reason that the Mac App Store and similar projects is incompatible with GPL licensed apps is not inherent in the concept of an app store but is rather specifically due to Apple s terms of use requirement 137 that all apps in the store utilize Apple DRM restrictions Ubuntu s app store does not demand any such requirement These terms do not limit or restrict your rights under any applicable open source software licenses 139 Microsoft Edit Main article Microsoft and open source In 2001 Microsoft CEO Steve Ballmer referred to Linux as a cancer that attaches itself in an intellectual property sense to everything it touches 140 141 In response to Microsoft s attacks on the GPL several prominent Free Software developers and advocates released a joint statement supporting the license 142 Microsoft has released Microsoft Windows Services for UNIX which contains GPL licensed code In July 2009 Microsoft itself released a body of around 20 000 lines of Linux driver code under the GPL 143 The Hyper V code that is part of the submitted code used open source components licensed under the GPL and was originally statically linked to proprietary binary parts the latter being inadmissible in GPL licensed software 144 Viral nature Edit The description of the GPL as viral when called General Public Virus or GNU Public Virus GPV dates back to a year after the GPLv1 was released 145 In 2001 the term received broader public attention when Craig Mundie Microsoft Senior Vice President described the GPL as being viral 146 Mundie argues that the GPL has a viral effect in that it only allows the conveyance of whole programs which means programs that link to GPL libraries must themselves be under a GPL compatible license else they cannot be combined and distributed In 2006 Richard Stallman responded in an interview that Mundie s metaphor of a virus is wrong as software under the GPL does not attack or infect other software Accordingly Stallman believes that comparing the GPL to a virus is inappropriate and that a better metaphor for software under the GPL would be a spider plant if one takes a piece of it and puts it somewhere else it grows there too 147 On the other hand the concept of a viral nature of the GPL was taken up by others later too 148 149 For instance a 2008 article stated The GPL license is viral meaning any derivative work you create containing even the smallest portion of the previously GPL licensed software must also be licensed under the GPL license 150 Barrier to commercialization Edit Main article Business models for open source software The FreeBSD project has stated that a less publicized and unintended use of the GPL is that it is very favorable to large companies that want to undercut software companies In other words the GPL is well suited for use as a marketing weapon potentially reducing overall economic benefit and contributing to monopolistic behavior and that the GPL can present a real problem for those wishing to commercialize and profit from software 151 Richard Stallman wrote about the practice of selling license exceptions to free software licenses as an example of ethically acceptable commercialization practice Selling exceptions here means that the copyright holder of a given software releases it along with the corresponding source code to the public under a free software license then lets customers pay for permission to use the same code under different terms for instance allowing its inclusion in proprietary applications Stallman considered selling exceptions acceptable since the 1990s and on occasion I ve suggested it to companies Sometimes this approach has made it possible for important programs to become free software Although the FSF does not practice selling exceptions a comparison with the X11 license which is a non copyleft free software license is proposed for suggesting that this commercialization technique should be regarded as ethically acceptable Releasing a given program under a non copyleft free software license would permit embedding the code in proprietary software Stallman comments that either we have to conclude that it s wrong to release anything under the X11 license a conclusion I find unacceptably extreme or reject this implication Using a non copyleft license is weak and usually an inferior choice but it s not wrong In other words selling exceptions permits some embedding in proprietary software and the X11 license permits even more embedding If this doesn t make the X11 license unacceptable it doesn t make selling exceptions unacceptable 152 Open source criticism Edit In 2000 developer and author Nikolai Bezroukov published an analysis and comprehensive critique of GPL s foundations and Stallman s software development model called Labyrinth of Software Freedom 153 154 Version 2 of the WTFPL Do What The Fuck You Want To Public License was created by Debian project leader Sam Hocevar in 2004 as a parody of the GPL 155 In 2005 open source software advocate Eric S Raymond questioned the relevance of GPL then for the FOSS ecosystem stating We don t need the GPL anymore It s based on the belief that open source software is weak and needs to be protected Open source would be succeeding faster if the GPL didn t make lots of people nervous about adopting it 156 Richard Stallman replied GPL is designed to ensure that every user of a program gets the essential freedoms to run it to study and change the source code to redistribute copies and to publish modified versions Raymond addresses the issue in terms of different goals and values those of open source which do not include defending software users freedom to share and change software 157 In 2007 Allison Randal who took part in the GPL draft committee criticized the GPLv3 for being incompatible with the GPLv2 158 and for missing clarity in the formulation 159 Similarly Whurley prophesied in 2007 the downfall of the GPL due to the lack of focus for the developers with GPLv3 which would drive them towards permissive licenses 160 In 2009 David Chisnall described in an InformIT article The Failure of the GPL the problems with the GPL among them incompatibility and complexity of the license text 161 In 2014 dtrace developer and Joyent CTO Bryan Cantrill called the copyleft GPL a Corporate Open Source Anti pattern by being anti collaborative and recommended instead permissive software licenses 162 GPLv3 criticism Edit Already in September 2006 in the draft process of the GPLv3 several high profile developers of the Linux kernel for instance Linus Torvalds Greg Kroah Hartman and Andrew Morton warned on a splitting of the FOSS community the release of GPLv3 portends the Balkanisation of the entire Open Source Universe upon which we rely 31 Similarly Benjamin Mako Hill argued in 2006 on the GPLv3 draft noting that a united collaborating community is more important than a single license 163 Following the GPLv3 release in 2007 some journalists 35 121 164 and Toybox developer Rob Landley 38 39 criticized that with the introduction of the GPLv3 the split between the open source and free software community became wider than ever As the significantly extended GPLv3 is essentially incompatible with the GPLv2 93 compatibility between both is only given under the optional or later clause of the GPL which was not taken for instance by the Linux kernel 33 Bruce Byfield noted that before the release of the GPLv3 the GPLv2 was a unifying element between the open source and the free software community 121 For the LGPLv3 GNU TLS maintainer Nikos Mavrogiannopoulos similarly argued If we assume that its the LGPLv3 primary goal is to be used by free software then it blatantly fails that 165 after he re licensed GNU TLS from LGPLv3 back to LGPLv2 1 due to license compatibility issues 166 Lawrence Rosen attorney and computer specialist praised in 2007 how the community using the Apache license was now able to work together with the GPL community in a compatible manner as the problems of GPLv2 compatibility with Apache licensed software were resolved with the GPLv3 He said I predict that one of the biggest success stories of GPLv3 will be the realization that the entire universe of free and open source software can thus be combined into comprehensive open source solutions for customers worldwide 167 In July 2013 Flask developer Armin Ronacher draws a less optimistic conclusion on the GPL compatibility in the FOSS ecosystem When the GPL is involved the complexities of licensing becomes a non fun version of a riddle also noting that the conflict between Apache License 2 0 and GPLv2 still has impact on the ecosystem 168 See also Edit nbsp Free and open source software portalCriticism of copyright Multi licensing European Union Public Licence EUPL GPL font exception GPL linking exception Comparison of free and open source software licenses Free software license Category Software using the GPL license Public information licenceNotes Edit Sections 3a and 3b of the license Sections 2b and 4 of the license GPLv3 broke the GPL into incompatible forks that can t share code FSF expected universal compliance but hijacked lifeboat clause when boat wasn t sinking 38 39 example if only GNU Lesser General Public License LGPL libraries LGPL software components and components with permissive free software licenses are used thus not GPL itself then only the source code of LGPL parts has to be made available for the developer s own self developed software components this is not required even when the underlying operating system used is licensed under GPL as is the case with Linux A counterexample is the GPL ed GNU Bison the parsers it outputs do contain parts of itself and are therefore derivatives which would fall under the GPL if not for a special exception granted by GNU Bison 48 See Progress Software Corporation v MySQL AB 195 F Supp 2d 328 D Mass 2002 on defendant s motion for preliminary injunction References Edit a b c d e Top 20 licenses Black Duck Software 19 November 2015 Archived from the original on 19 July 2016 Retrieved 19 November 2015 GPL FAQ Does using the GPL for a program make it GNU Software GNU Project Free Software Foundation a b c David A Wheeler Estimating Linux s Size a b c Freecode s statistics page Archived from the original on 28 August 2008 GPL 60 5 lGPLv2 6 9 GPLv2 1 9 GPLv3 1 6 a b c Asay Matt 23 July 2009 GPLv3 hits 50 percent adoption The Open Road CNET News News cnet com Archived from the original on 29 October 2013 Retrieved 2 September 2013 a b c License proliferation a naive quantitative analysis on lwn net Walter van Holst is a legal consultant at the Dutch IT consulting company mitopics Walter instead chose to use data from a software index namely Freecode Walter s 2009 data set consisted of 38 674 projects The final column in the table shows the number of projects licensed under any version of the GPL In addition Walter presented pie charts that showed the proportion of projects under various common licenses Notable in those data sets was that whereas in 2009 the proportion of projects licensed GPLv2 only and GPLv3 was respectively 3 and 2 by 2013 those numbers had risen to 7 and 5 Why the GPL rocketed Linux to success Archived from the original on 16 May 2013 Retrieved 22 September 2006 So while the BSDs have lost energy every time a company gets involved the GPL ed programs gain every time a company gets involved GNU Emacs Copying Permission Notice 1985 GitHub Retrieved 8 November 2015 The History of the GPL Retrieved 24 November 2011 a b c Stallman Richard 21 April 2006 Presentation at the second international GPLv3 conference held in Porto Alegre Why Upgrade to GPL Version 3 GPLv3 Fsf org Retrieved 17 March 2011 FSF releases the GNU General Public License version 3 Free Software Foundation working together for free software Fsf org Retrieved 15 January 2011 GNU General Public License version 1 New General Public License For the reasoning see The GNU project GNU Library General Public License version 2 0 Retrieved 21 November 2018 SPDX License List Software Package Data Exchange SPDX Retrieved 14 September 2021 a b Stallman Richard 25 February 2006 Presentation in Brussels Belgium the first day of that year s FOSDEM conference GPLv3 authors comment on final draft Retrieved 4 March 2008 permanent dead link The GPLv3 process Public consultation and private drafting Archived from the original on 24 June 2008 Retrieved 4 March 2008 Interview with Richard Stallman Archived 20 November 2017 at the Wayback Machine Free Software Magazine 23 January 2008 GPLv3 Drafting version 3 of the GNU General Public License Free Software Foundation Europe gplv3 fsf org comments for discussion draft 4 Archived from the original on 2 October 2008 Retrieved 31 March 2008 gplv3 fsf org comments for draft 1 Archived from the original on 26 June 2008 Retrieved 31 March 2008 Showing comments in file gplv3 draft 1 found 962 gplv3 fsf org comments for draft 2 Archived from the original on 24 July 2008 Retrieved 31 March 2008 Showing comments in file gplv3 draft 1 found 727 gplv3 fsf org comments for draft 3 Archived from the original on 3 July 2008 Retrieved 31 March 2008 Showing comments in file gplv3 draft 3 found 649 gplv3 fsf org comments for draft 4 Archived from the original on 2 October 2008 Retrieved 31 March 2008 Showing comments in file gplv3 draft 4 found 298 Guide to the third draft of GPLv3 Final Discussion Draft Retrieved 4 June 2007 GPL version 3 FAQ Retrieved 4 June 2007 Fourth Discussion Draft Rationale PDF Retrieved 4 June 2007 Tiemann Michael 7 June 2007 GNU Affero GPL version 3 and the ASP loophole OSI Archived from the original on 14 August 2020 Retrieved 19 August 2013 List of free software licences on the FSF website We recommend that developers consider using the GNU AGPL for any software which will commonly be run over a network GPL FAQ Why did you decide to write the GNU Affero GPLv3 as a separate license GNU Project Free Software Foundation a b c James E J Bottomley Mauro Carvalho Chehab Thomas Gleixner Christoph Hellwig Dave Jones Greg Kroah Hartman Tony Luck Andrew Morton Trond Myklebust David Woodhouse 15 September 2006 Kernel developers position on GPLv3 The Dangers and Problems with GPLv3 LWN net Retrieved 11 March 2015 The current version Discussion Draft 2 of GPLv3 on first reading fails the necessity test of section 1 on the grounds that there s no substantial and identified problem with GPLv2 that it is trying to solve However a deeper reading reveals several other problems with the current FSF draft 5 1 DRM Clauses 5 2 Additional Restrictions Clause 5 3 Patents Provisions since the FSF is proposing to shift all of its projects to GPLv3 and apply pressure to every other GPL licensed project to move we foresee the release of GPLv3 portends the Balkanisation of the entire Open Source Universe upon which we rely Petreley Nicholas 27 September 2006 A fight against evil or a fight for attention linuxjournal com Retrieved 11 March 2015 Second the war between Linus Torvalds and other Kernel developers and the Free Software Foundation over GPLv3 is continuing with Torvalds saying he s fed up with the FSF a b c d Torvalds Linus COPYING kernel org Retrieved 13 August 2013 T he only valid version of the GPL as far as the kernel is concerned is this particular version of the license ie v2 not v2 2 or v3 x or whatever unless explicitly otherwise stated Linus Torvalds says GPL v3 violates everything that GPLv2 stood for Debconf 2014 Portland Oregon accessed 11 March 2015 a b c Kerner Sean Michael 8 January 2008 Torvalds Still Keen On GPLv2 Internet News internetnews com Retrieved 12 February 2015 In some ways Linux was the project that really made the split clear between what the FSF is pushing which is very different from what open source and Linux has always been about which is more of a technical superiority instead of a this religious belief in freedom Torvalds told Zemlin So the GPL Version 3 reflects the FSF s goals and the GPL Version 2 pretty closely matches what I think a license should do and so right now Version 2 is where the kernel is GPL 3 Overview Tech LawForum 29 June 2007 Retrieved 2 September 2013 A Quick Guide to GPLv3 GNU Software Project Free Software Foundation a b Landley Rob Embedded Linux Conference 2013 Toybox Writing a New Command Line The Linux Foundation Archived from the original video on 27 October 2021 Retrieved 24 June 2016 a b Landley Rob Transcript of CELF 2013 Toybox talk landley net Retrieved 21 August 2013 Linus Torvalds 8 September 2000 Linux 2 4 0 test8 lkml iu edu Retrieved 21 November 2015 The only one of any note that I d like to point out directly is the clarification in the COPYING file making it clear that it s only that particular version of the GPL that is valid for the kernel This should not come as any surprise as that s the same license that has been there since 0 12 or so but I thought I d make that explicit GNU General Public License Retrieved 15 June 2012 a b Selling Free Software GNU Project Free Software Foundation GPL FAQ Use GPL Tools to develop non free programs GNU Project Free Software Foundation GPL FAQ GPL require source posted to public GNU Project Free Software Foundation GPL FAQ Unreleased modifications GNU Project Free Software Foundation GPL FAQ Internal Distribution GNU Project Free Software Foundation a b GPL FAQ Port program to GNU Linux GNU Project Free Software Foundation A Quick Guide to GPLv3 GNU Project Free Software Foundation FSF Free Software Foundation De Laat Paul B December 2005 Copyright or copyleft Research Policy 34 10 1511 1532 doi 10 1016 j respol 2005 07 003 Conditions for Using Bison GNU Project Free Software Foundation Retrieved 11 December 2008 Reasoning behind the preferred form language in the GPL LWN net 7 March 2011 Stallman Richard M 9 June 2006 Don t Let Intellectual Property Twist Your Ethos Moglen Eben 22 June 2006 Will the Not a contract phrase go Transcript 3nd international GPLv3 conference Barcelona Guadamuz Gonzalez Andres 2004 Viral contracts or unenforceable documents Contractual validity of copyleft licenses European Intellectual Property Review 26 8 331 339 SSRN 569101 Allison Randal 14 May 2007 GPLv3 Clarity and Simplicity Archived from the original on 15 October 2008 Keith Collins 11 May 2017 A federal court has ruled that an open source license is an enforceable contract SFC v Vizio remanded back to California state courts LWN net lwn net Retrieved 10 June 2022 GPL FAQ Can I modify the GPL and make a modified license GNU Project Free Software Foundation The GNU General Public License Version 3 Free Software Foundation 29 June 2007 Retrieved 21 July 2009 GPL FAQ Can I modify the GPL and make a modified license GNU Project Free Software Foundation 9 June 2017 Retrieved 11 July 2017 GPL FAQ Does the GPL require that source code of modified versions be posted to the public GNU Project Free Software Foundation Frequently Asked Questions about the GNU Licenses GPL FAQ GNU Project Free Software Foundation Retrieved 15 March 2011 Why you shouldn t use the Lesser GPL for your next library GNU Project Free Software Foundation Retrieved 15 January 2011 Linus Torvalds GPL only modules linux kernel mailing list 17 December 2006 Matt Asay The GPL Understanding the License that Governs Linux Archived 6 October 2008 at the Wayback Machine Novell Cool Solutions Feature 16 Jan 2004 Lewis Galoob Toys Inc v Nintendo of America Inc 964 F 2d 965 10 9th Cir 21 May 1992 a b Lawrence Rosen Derivative Works Linux Journal 1 January 2003 Derivative Works Rosenlaw amp Einschlag 25 May 2004 Matt 29 January 2009 Why They re Wrong WordPress Plugins Shouldn t Have to be GPL Webmaster Source Retrieved 15 January 2011 Licensing Drupal org Retrieved 15 January 2011 GPL FAQ Can I apply the GPL when writing a plug in for a nonfree program GNU Project Free Software Foundation Retrieved 15 January 2011 MereAggregation What constitutes combining two parts into one program This is a legal question which ultimately judges will decide We believe that a proper criterion depends both on the mechanism of communication exec pipes rpc function calls within a shared address space etc and the semantics of the communication what kinds of information are interchanged on gnu org 12 Years of GPL Compliance A Historical Perspective by Bradley Kuhn Slide 10 Common Lisp Readline and GPL Mail on 6 November 21 31 Judge Saris defers GNU GPL Questions for Trial in MySQL vs Progress Software gnu org Retrieved 24 March 2011 JOINT STATUS REPORT Case 2 03 cv 00294 DN Document 1179 PDF IN THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF UTAH CENTRAL DIVISION 16 February 2018 Retrieved 25 January 2019 Vaughan Nichols Steven J Last of original SCO v IBM Linux lawsuit settled ZDNet Retrieved 4 December 2021 Groklaw The German GPL Order Translated groklaw net Bird amp Bird A Review of German Case Law on the GNU General Public License 17 December 2007 retrieved 1 March 2012 Dismissal of Wallace v FSF From this article on Groklaw 판결문 GNU 프로젝트 자유 소프트웨어 재단 FSF gnu org Archived from the original on 18 October 2007 Welte Harald 22 September 2006 gpl violations org project prevails in court case on GPL violation by gpl violations org D Link Judgement PDF Archived from the original PDF on 26 April 2013 Ewing James 1 August 2004 Linux on Linksys Wi Fi Routers Linux Journal Retrieved 23 January 2012 a b Free Software Foundation Files Suit Against Cisco For GPL Violations Press release Free Software Foundation 11 December 2008 Retrieved 22 August 2011 FSF Settles Suit Against Cisco Press release Free Software Foundation 20 May 2009 Retrieved 22 August 2011 Brockmeier Joe 29 July 2011 Say what GNU Emacs violates the GPL Network World Retrieved 19 January 2016 Naughton Edward J 8 August 2011 License revoked Applying Section 4 of the GPL and the lessons of Best Buy to Google s Android brownrudnick com Archived from the original on 27 January 2016 Soulskill 29 July 2011 Emacs Has Been Violating the GPL Since 2009 slashdot org Stallman Richard 28 July 2011 Re Compiled files without sources lists gnu org A federal court has ruled that the GPL is an enforceable contract LWN net 15 May 2017 Retrieved 17 May 2021 Robertson Donald 11 October 2017 Update on Artifex v Hancom GNU GPL compliance case Free Software Foundation Retrieved 17 May 2021 Our lawsuit against ChessBase Stockfish Open Source Chess Engine stockfishchess org Retrieved 22 November 2022 Statement on Fat Fritz 2 Stockfish Open Source Chess Engine stockfishchess org Retrieved 22 November 2022 ChessBase GmbH and the Stockfish team reach an agreement and end their legal dispute Stockfish Open Source Chess Engine stockfishchess org Retrieved 22 November 2022 Settlement German PDF 7 November 2022 Retrieved 22 November 2022 Settlement English PDF 7 November 2022 Retrieved 22 November 2022 The GNU General Public License v3 0 GNU Project Free Software Foundation Retrieved 24 March 2010 a b GPL FAQ Is GPLv3 compatible with GPLv2 GNU Project Free Software Foundation Retrieved 3 June 2014 No Some of the requirements in GPLv3 such as the requirement to provide Installation Information do not exist in GPLv2 As a result the licenses are not compatible if you tried to combine code released under both these licenses you would violate section 6 of GPLv2 However if code is released under GPL version 2 or later that is compatible with GPLv3 because GPLv3 is one of the options it permits Larabel Michael 24 January 2013 FSF Wastes Away Another High Priority Project Phoronix Archived from the original on 9 November 2016 Retrieved 22 August 2013 Both LibreCAD and FreeCAD both want to use LibreDWG and have patches available for supporting the DWG file format library but can t integrate them The programs have dependencies on the popular GPLv2 license while the Free Software Foundation will only let LibreDWG be licensed for GPLv3 use not GPLv2 Prokoudine Alexandre 27 December 2012 LibreDWG drama the end or the new beginning libregraphicsworld org Archived from the original on 9 November 2016 Retrieved 23 August 2013 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 GNU Lesser General Public License v2 1 GNU Project Free Software Foundation FSF fsf org Retrieved 26 April 2011 GPL FAQ How are the various GNU licenses compatible with each other GNU Project Free Software Foundation Retrieved 13 April 2011 Various licenses with comments GPL Compatible Free Software Licenses FSF Retrieved 20 April 2012 GPL FAQ What does it mean to say that two licenses are compatible GNU Project Free Software Foundation Retrieved 14 April 2011 GPL FAQ What does it mean to say a license is compatible with the GPL GNU Project Free Software Foundation Retrieved 14 April 2011 Black Duck Open Source Resource Center blackducksoftware com Archived from the original on 14 October 2012 Retrieved 26 April 2011 Compatible Licenses ShareAlike compatibility GPLv3 Creative Commons wiki creativecommons org Make Your Open Source Software GPL Compatible Or Else David A Wheeler Retrieved 26 April 2011 Linux ZFS Licenses and Patents Tag1 Consulting Archived from the original on 12 June 2011 GPL FAQ Can I use the GPL for something other than software GNU Project Free Software Foundation Retrieved 20 June 2009 GPL FAQ Why don t you use the GPL for manuals GNU Project Free Software Foundation Retrieved 20 June 2009 Srivastava Manoj 2006 Draft Debian Position Statement about the GNU Free Documentation License GFDL Retrieved 25 September 2007 It is not possible to borrow text from a GFDL d manual and incorporate it in any free software program whatsoever This is not a mere license incompatibility It s not just that the GFDL is incompatible with this or that free software license it s that it is fundamentally incompatible with any free software license whatsoever So if you write a new program and you have no commitments at all about what license you want to use saving only that it be a free license you cannot include GFDL d text The GNU FDL as it stands today does not meet the Debian Free Software Guidelines There are significant problems with the license as detailed above and as such we cannot accept works licensed under the GNU FDL into our distribution Debian Project Resolution Why the GNU Free Documentation License is not suitable for Debian Voted February March 2006 Retrieved 20 June 2009 License Change FLOSS Manuals Foundation 6 June 2007 Archived from the original on 28 February 2008 Retrieved 20 June 2009 Font Licensing Free Software Foundation 25 April 2005 GPL FAQ How does the GPL apply to fonts GNU Project Free Software Foundation a b David A Wheeler Make Your Open Source Software GPL Compatible Or Else a b c Top 20 licenses Black Duck Software 23 August 2013 Archived from the original on 19 July 2016 Retrieved 23 August 2013 SourceForge net Software Map Dwheeler com Archived from the original on 13 February 2017 Retrieved 17 November 2008 License gt OSI GNU General Public License GPL 32641 projects GNU Library or Lesser General Public License LGPL 4889 projects of 45727 82 1 Mark 8 May 2008 The Curse of Open Source License Proliferation socializedsoftware com Archived from the original on 8 December 2015 Retrieved 30 November 2015 Currently the decision to move from GPL v2 to GPL v3 is being hotly debated by many open source projects According to Palamida a provider of IP compliance software there have been roughly 2489 open source projects that have moved from GPL v2 to later versions MySQL changes license to avoid GPLv3 Computer business review online 4 January 2007 Archived from the original on 6 February 2007 corbet 1 October 2006 Busy busy busybox lwn net Retrieved 21 November 2015 Since BusyBox can be found in so many embedded systems it finds itself at the core of the GPLv3 anti DRM debate The real outcomes however are this BusyBox will be GPLv2 only starting with the next release It is generally accepted that stripping out the or any later version is legally defensible and that the merging of other GPLv2 only code will force that issue in any case Landley Rob 9 September 2006 Re Move GPLv2 vs v3 fun lwn net Retrieved 21 November 2015 Don t invent a straw man argument please I consider licensing BusyBox under GPLv3 to be useless unnecessary overcomplicated and confusing and in addition to that it has actual downsides 1 Useless We re never dropping GPLv2 HP Press Release HP Contributes Source Code to Open Source Community to Advance Adoption of Linux www hp com Prokoudine Alexandre 26 January 2012 What s up with DWG adoption in free software libregraphicsworld org Archived from the original on 9 November 2016 Retrieved 5 December 2015 Blender s Toni Roosendaal Blender is also still GPLv2 or later For the time being we stick to that moving to GPL 3 has no evident benefits I know of License blender org Retrieved 17 December 2016 The source code we develop at blender org is default being licensed as GNU GPL Version 2 or later Denis Courmont Remi VLC media player to remain under GNU GPL version 2 videolan org Retrieved 21 November 2015 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 Copyright MediaWiki a b c d Byfield Bruce 22 November 2011 7 Reasons Why Free Software Is Losing Influence Page 2 Datamation com Retrieved 23 August 2013 At the time the decision seemed sensible in the face of a deadlock But now GPLv2 is used for 42 5 of free software and GPLv3 for less than 6 5 according to Black Duck Software GPL copyleft use declining faster than ever on ITworld on 16 December 2011 by Brian Proffitt Proffitt Brian 16 December 2011 GPL copyleft use declining faster than ever Data suggests a sharper rate of decline which raises the question why IT world Retrieved 23 August 2013 Aslett Matthew 15 December 2011 On the continuing decline of the GPL the451group com Archived from the original on 9 December 2016 Retrieved 26 November 2015 The Top Licenses on Github Archived 4 March 2016 at the Wayback Machine on ostatic com by Jon Buys 7 February 2012 tags letter g tagged as GPL family including misnamed variants 21000 100 3000 2000 400 of 47985 projects on freecode 18 June 2014 frozen About Freecode Archived 31 October 2011 at the Wayback Machine on freecode com The Freecode site has been moved to a static state effective 18 June 2014 due to low traffic levels and so that folks will focus on more useful endeavors than site upkeep GPL use in Debian on the rise study Itwire com Retrieved 2 September 2013 Surveying open source licenses Lwn net Retrieved 2 September 2013 Mark 8 May 2008 The Curse of Open Source License Proliferation socializedsoftware com Archived from the original on 8 December 2015 Retrieved 30 November 2015 Top 20 Most Commonly Used Open Source Licenses Shaun Connolly 11 March 2009 Top 20 licenses Black Duck Software 6 June 2016 Archived from the original on 19 July 2016 Retrieved 6 June 2016 Top 20 licenses Black Duck Software 2 January 2017 Archived from the original on 19 July 2016 Retrieved 2 January 2017 Top 20 licenses Black Duck Software 4 June 2018 Archived from the original on 19 July 2016 Retrieved 4 June 2018 Balter Ben 9 March 2015 Open source license usage on GitHub com github com Retrieved 21 November 2015 Anwesha Das 22 June 2016 Software Licenses in Fedora Ecosystem anweshadas in Retrieved 1 November 2016 From the above chart it is clear that the GPL family is the highest used I had miscalculated it as MIT before The other major licenses are MIT BSD the LGPL family Artistic for Perl packages LPPL fo r texlive packages ASL Open Source Licensing Trends 2017 vs 2016 on whitesourcesoftware com by Sivan Michaeli 12 April 2018 a b The GPL the App Store and You on engadget com 2011 Copyright Policy OpenBSD Ubuntu One Terms and Conditions One ubuntu com 29 August 2013 Archived from the original on 25 September 2013 Retrieved 25 September 2013 Newbart Dave 1 June 2001 Microsoft CEO takes launch break with the Sun Times Chicago Sun Times Archived from the original on 15 June 2001 Internet archive link GNU GENERAL PUBLIC LICENSE Version 2 June 1991 dwheeler com Wheeler David A Archived from the original on 15 May 2013 Retrieved 6 December 2008 Free Software Leaders Stand Together via Wikisource Clarke Gavin 20 July 2009 Microsoft embraces Linux cancer to sell Windows servers The Register Clarke Gavin 23 July 2009 Microsoft opened Linux driver code after violating GPL The Register Vixie Paul 6 March 2006 Re Section 5 2 IPR encumberance in TAK rollover requirement draft IETF Namedroppers mailing list Archived from the original on 27 September 2007 Retrieved 29 April 2007 General Public Virus Jargon File 2 2 1 15 December 1990 Retrieved 29 April 2007 Hackvan Stig September 1999 Reverse engineering the GNU Public Virus Is copyleft too much of a good thing Linux Journal Archived from the original on 18 July 2011 Retrieved 29 April 2007 Stewart Bill 8 October 1998 Re propose cypherpunks license Re Wanted Twofish source code Cypherpunks mailing list Archived from the original on 29 May 2007 Retrieved 29 April 2007 Buck Joe 10 October 2000 Re Using of parse tree externally GCC mailing list Retrieved 29 April 2007 Griffis L Adrian 15 July 2000 The GNU Public Virus Archived from the original on 30 September 2007 Retrieved 29 April 2007 Speech Transcript Craig Mundie The New York University Stern School of Business Prepared Text of Remarks by Craig Mundie Microsoft Senior Vice President The Commercial Software Model The New York University Stern School of Business 3 May 2001 Poynder Richard 21 March 2006 The Basement Interviews Freeing the Code Retrieved 5 February 2010 Chopra Samir Dexter Scott 14 August 2007 Decoding liberation the promise of free and open source software Routledge p 56 ISBN 978 0 415 97893 4 Williams Sam March 2002 Free as in Freedom Richard Stallman s Crusade for Free Software O Reilly Media ISBN 0 596 00287 4 Nikolai Bezroukov 2001 Comparative merits of GPL BSD and Artistic licences Critique of Viral Nature of GPL v 2 or In Defense of Dual Licensing Idea Archived from the original on 22 December 2001 Viral property stimulates proliferation of licenses and contributes to the GPL enforced nightmare a situation when many other licenses are logically incompatible with the GPL and make life unnecessary difficult for developers working in the Linux environment KDE is a good example here Python is a less known example Geere Duncan 16 December 2011 Some rights reserved the alternatives to copyright Wired UK Wired UK Wired co uk Retrieved 30 May 2015 Inoculating Your Purchase Contractual Protection from Viral Licenses in M amp A Transactions PDF Friedfrank com Retrieved 30 May 2015 http www buddlefindlay com article 2013 07 01 legal update on information and communication technology E2 80 93 july 2013 Archived 16 March 2015 at the Wayback Machine New Media Rights 12 September 2008 Open Source Licensing Guide California Western School of Law Retrieved 28 November 2015 Montague Bruce 13 November 2013 GPL Advantages and Disadvantages FreeBSD Retrieved 28 November 2015 Richard Stallman 2010 On Selling Exceptions to the GNU GPL Free Software Foundation Bezroukov Nikolai Labyrinth of Software Freedom BSD vs GPL and social aspects of free licensing debate on softpanorama org by Nikolai Bezroukov Accessed 23 September 2010 The Scope of Open Source Licensing Archived 9 January 2016 at the Wayback Machine Harvard University by Josh Lerner and Jean Tirole 2002 Sam Hocevar 21 September 2015 Should I change the name of the WTFPL Programmers Stack Exchange User comment Retrieved 19 July 2016 The WTFPL is a parody of the GPL which has a similar copyright header and list of permissions to modify i e none see for instance gnu org licenses gpl 3 0 en html The purpose of the WTFPL wording is to give more freedom than the GPL does Biancuzzi Federico 30 June 2005 ESR We Don t Need the GPL Anymore onlamp com Archived from the original on 17 April 2018 Retrieved 10 February 2015 We don t need the GPL anymore It s based on the belief that open source software is weak and needs to be protected Open source would be succeeding faster if the GPL didn t make lots of people nervous about adopting it RMS The GNU GPL Is Here to Stay onlamp com 22 September 2005 Archived from the original on 17 January 2015 Retrieved 12 February 2015 ESR addresses the issue in terms of different goals and values those of open source which do not include defending software users freedom to share and change software Perhaps he thinks the GNU GPL is not needed to achieve those goals Randal Allison 13 April 2007 GPLv3 Linux and GPLv2 Compatibility radar oreilly com O Reilly Media Retrieved 19 January 2016 You might think the FSF would have to be insane to unleash this licensing hell If the license were purely a cleaned up version of the GPLv2 there would be no incompatibility the FSF would have no agenda involved in getting projects to update to the new license and at the same time there would be no reason for projects to object to updating Smooth sailing Randal Allison 14 May 2007 GPLv3 Clarity and Simplicity radar oreilly com O Reilly Media Retrieved 19 January 2016 Looking at the near finished draft I have to say it s unlikely that they ever considered simplicity a priority if they considered it at all The language choices of an open source license can support that freedom can empower the users and the developers The GPLv3 doesn t Whurley 6 June 2007 The Death Of A Software License Archived from the original on 11 October 2008 Retrieved 24 June 2016 Version 3 is going to distance Richard Stallman and the Free Software Foundation from the developers that make the organization so influential to begin Chisnall David 31 August 2009 The Failure of the GPL informit com Retrieved 24 January 2016 Cantrill Bryan 17 September 2014 Corporate Open Source Anti patterns YouTube Archived from the original on 27 October 2021 Retrieved 26 December 2015 Anti pattern Anti collaborative licensing Hill Benjamin Mako 28 January 2006 Notes on the GPLv3 linux com Retrieved 25 January 2016 The GPL is one thing that almost everyone in the free and open source software communities have in common For that reason the revision has the potential to highlight disagreements differences in opinion differences in business models and differences in tactics We would be wise to remember that the potential for the GPL to hinder our ability to work together is far more dangerous than the even the most radical change textual change the FSF might suggest Above all we must remember that our community and its goals are more important than any single license no matter how widespread McDougall Paul 10 July 2007 Linux Creator Calls GPLv3 Authors Hypocrites As Open Source Debate Turns Nasty informationweek com Archived from the original on 13 April 2008 Retrieved 12 February 2015 the latest sign of a growing schism in the open source community between business minded developers like Torvalds and free software purists Mavrogiannopoulos Nikos 26 March 2013 The perils of LGPLv3 gnutls org Retrieved 18 November 2015 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 GnuTLS 3 1 10 changelog www gnutls org Nikos Mavrogiannopoulos 18 December 2012 gnutls is moving Retrieved 11 December 2012 Rosen Lawrence 2007 Comments on GPLv3 Rosenlaw com Retrieved 22 August 2014 Ronacher Armin 23 July 2013 Licensing in a Post Copyright World lucumr pocoo org Retrieved 18 November 2015 The License Compatibility Clusterfuck When the GPL is involved the complexities of licensing becomes a non fun version of a riddle So many things to consider and so many interactions to consider And that GPL incompatibilities are still an issue that actively effects people is something many appear to forget For instance one would think that the incompatibility of the GPLv2 with the Apache Software License 2 0 should be a thing of the past now that everything upgrades to GPLv3 but it turns out that enough people are either stuck with GPLv2 only or do not agree with the GPLv3 that some Apache Software licensed projects are required to migrate For instance Twitter s Bootstrap is currently migrating from ASL2 0 to MIT precisely because some people still need GPLv2 compatibility Among those projects that were affected were Drupal WordPress Joomla the MoinMoin Wiki and others And even that case shows that people don t care that much about licenses any more as Joomla 3 just bundled bootstrap even though they were not licenses in a compatible way GPLv2 vs ASL 2 0 The other traditional case of things not being GPL compatible is the OpenSSL project which has a license that does not go well with the GPL That license is also still incompatible with the GPLv3 The whole ordeal is particularly interesting as some not so nice parties have started doing license trolling through GPL licenses Ronacher Armin 2009 Are you sure you want to use the GPL lucumr pocoo org External links Edit nbsp Wikibooks has a book on the topic of FOSS Licensing GNU General Public License version 3 GNU General Public License v2 0 This version is deprecated by the FSF but is still used by many software projects including Linux kernel and GNU packages GNU General Public License v1 0 This version is deprecated by the FSF The Emacs General Public License a February 1988 version a direct predecessor of the GNU GPL History of the GPL by Li Cheng Tai 4 July 2001 A Practical Guide to GPL Compliance Covers GPLv2 and v3 from the Software Freedom Law Center A paper on enforcing the GPL Frequently Asked Questions about the GPL GNU General Public License and Commentaries edited by Robert Chassell List of presentation transcripts about the GPL and free software licenses Archived 12 November 2015 at the Wayback Machine by the FSFE The Labyrinth of Software Freedom BSD vs GPL and social aspects of free licensing debate by Nikolai Bezroukov Retrieved from https en wikipedia org w index php title GNU General Public License amp oldid 1180665792 Version 3, wikipedia, wiki, book, books, library,

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