The GNU Free Documentation License (GNU FDL or GFDL) is a
copyleft license
A license (American English) or licence (Commonwealth English) is an official permission or permit to do, use, or own something (as well as the document of that permission or permit).
A license is granted by a party (licensor) to another part ...
for free documentation, designed by the
Free Software Foundation
The Free Software Foundation (FSF) is a 501(c)(3) non-profit organization founded by Richard Stallman on October 4, 1985. The organisation supports the free software movement, with the organization's preference for software being distributed ...
(FSF) for the
GNU Project
The GNU Project ( ) is a free software, mass collaboration project announced by Richard Stallman on September 27, 1983. Its goal is to give computer users freedom and control in their use of their computers and Computer hardware, computing dev ...
. It is similar to the
GNU General Public License
The GNU General Public Licenses (GNU GPL or simply GPL) are a series of widely used free software licenses, or ''copyleft'' licenses, that guarantee end users the freedom to run, study, share, or modify the software. The GPL was the first ...
, giving readers the rights to copy, redistribute, and modify (except for "invariant sections") a work and requires all copies and derivatives to be available under the same license. Copies may also be sold commercially, but, if produced in larger quantities (greater than 100), the original document or source code must be made available to the work's recipient.
The GFDL was designed for
manuals, textbooks, other reference and instructional materials, and documentation which often accompanies GNU software. However, it can be used for any text-based work, regardless of subject matter. For example, the free online encyclopedia
Wikipedia
Wikipedia is a free content, free Online content, online encyclopedia that is written and maintained by a community of volunteers, known as Wikipedians, through open collaboration and the wiki software MediaWiki. Founded by Jimmy Wales and La ...
uses the GFDL (coupled with the
Creative Commons Attribution Share-Alike License) for much of its text, excluding text that was imported from other sources after the 2009 licensing update that is only available under the Creative Commons license.
History
The GFDL was released in draft form for feedback in September 1999. After revisions, version 1.1 was issued in March 2000, version 1.2 in November 2002, and version 1.3 in November 2008. The current state of the license is version 1.3.
On December 1, 2007, Wikipedia founder
Jimmy Wales announced that a long period of discussion and negotiation between and amongst the Free Software Foundation, Creative Commons, the
Wikimedia Foundation
The Wikimedia Foundation, Inc. (WMF) is an American 501(c)(3) nonprofit organization headquartered in San Francisco, California, and registered there as foundation (United States law), a charitable foundation. It is the host of Wikipedia, th ...
and others had produced a proposal supported by both the FSF and Creative Commons to modify the Free Documentation License in such a fashion as to allow the possibility for the Wikimedia Foundation to migrate the projects to the similar
Creative Commons Attribution Share-Alike (CC BY-SA) license. These changes were implemented on version 1.3 of the license, which includes a new provision allowing certain materials released under the (GFDL) license to be used under a Creative Commons Attribution Share-Alike license also.
Conditions
Material licensed under the current version of the license can be used for any purpose, as long as the use meets certain conditions.
* All previous authors of the work must be
attributed.
* All changes to the work must be logged.
* All
derivative work
In copyright law, a derivative work is an expressive creation that includes major copyrightable elements of a first, previously created original work (the underlying work). The derivative work becomes a second, separate work independent from ...
s must be licensed under the same license.
* The full text of the license, unmodified invariant sections as defined by the author if any, and any other added warranty disclaimers (such as a general disclaimer alerting readers that the document may not be accurate for example) and copyright notices from previous versions must be maintained.
* Technical measures such as
DRM may not be used to control or obstruct distribution or editing of the document.
Secondary sections
The license explicitly separates any kind of "Document" from "Secondary Sections", which may not be integrated with the Document, but exist as front-matter materials or appendices. Secondary sections can contain information regarding the author's or publisher's relationship to the subject matter, but not any subject matter itself. While the Document itself is wholly editable and is essentially covered by a license equivalent to (but mutually incompatible with) the
GNU General Public License
The GNU General Public Licenses (GNU GPL or simply GPL) are a series of widely used free software licenses, or ''copyleft'' licenses, that guarantee end users the freedom to run, study, share, or modify the software. The GPL was the first ...
, some of the secondary sections have various restrictions designed primarily to deal with proper attribution to previous authors.
Specifically, the authors of prior versions have to be acknowledged and certain "invariant sections" specified by the original author and dealing with his or her relationship to the subject matter may not be changed. If the material is modified, its title has to be changed (unless the prior authors permit to retain the title).
The license also has provisions for the handling of front-cover and back-cover texts of books, as well as for "History", "Acknowledgements", "Dedications" and "Endorsements" sections. These features were added in part to make the license more financially attractive to commercial publishers of software documentation, some of whom were consulted during the drafting of the GFDL.
[GNU Project:]
Frequently Asked Questions about the GNU Licenses: Why don't you use the GPL for manuals?
"Endorsements" sections are intended to be used in official standard documents, where the distribution of modified versions should only be permitted if they are not labeled as that standard anymore.
Commercial redistribution
The GFDL requires the ability to "copy and distribute the Document in any medium, either commercially or noncommercially" and therefore is incompatible with material that excludes commercial re-use. As mentioned above, the GFDL was designed with commercial publishers in mind, as Stallman explained: Material that restricts commercial re-use is incompatible with the license and cannot be incorporated into the work. However, incorporating such restricted material may be
fair use
Fair use is a Legal doctrine, doctrine in United States law that permits limited use of copyrighted material without having to first acquire permission from the copyright holder. Fair use is one of the limitations to copyright intended to bal ...
under United States copyright law (or
fair dealing in some other countries) and does not need to be licensed to fall within the GFDL if such fair use is covered by all potential subsequent uses. One example of such liberal and commercial fair use is
parody
A parody is a creative work designed to imitate, comment on, and/or mock its subject by means of satire, satirical or irony, ironic imitation. Often its subject is an Originality, original work or some aspect of it (theme/content, author, style, e ...
.
Compatibility with Creative Commons licensing terms
Although the two licenses work on similar copyleft principles, the GFDL is not compatible with the
Creative Commons Attribution-ShareAlike license.
However, at the request of the
Wikimedia Foundation
The Wikimedia Foundation, Inc. (WMF) is an American 501(c)(3) nonprofit organization headquartered in San Francisco, California, and registered there as foundation (United States law), a charitable foundation. It is the host of Wikipedia, th ...
,
version 1.3 added a time-limited section allowing specific types of websites using the GFDL to additionally offer their work under the CC BY-SA license. These exemptions allow a GFDL-based collaborative project with multiple authors to transition to the CC BY-SA 3.0 license, without first obtaining the permission of every author, if the work satisfies several conditions:
* The work must have been produced on a "Massive Multiauthor Collaboration Site" (MMC), such as a public
wiki for example.
* If external content originally published on a MMC is present on the site, the work must have been licensed under Version 1.3 of the GNU FDL, or an earlier version but with the "or any later version" declaration, with no cover texts or invariant sections. If it was not originally published on an MMC, it can only be
relicensed if it were added to an MMC before November 1, 2008.
To prevent the clause from being used as a general compatibility measure, the license itself only allowed the change to occur before August 1, 2009. At the release of version 1.3, the FSF stated that all content added before November 1, 2008, to Wikipedia as an example satisfied the conditions. The Wikimedia Foundation itself after a public referendum, invoked this process to
dual-license content released under the GFDL under the
CC BY-SA
A Creative Commons (CC) license is one of several public copyright licenses that enable the free distribution of an otherwise copyrighted "work". A CC license is used when an author wants to give other people the right to share, use, and bui ...
license in June 2009, and adopted a foundation-wide attribution policy for the use of content from Wikimedia Foundation projects.
Enforcement
There have currently been no cases involving the GFDL in a court of law, although its sister license for software, the
GNU General Public License
The GNU General Public Licenses (GNU GPL or simply GPL) are a series of widely used free software licenses, or ''copyleft'' licenses, that guarantee end users the freedom to run, study, share, or modify the software. The GPL was the first ...
, has been successfully enforced in such a setting. Although the content of
Wikipedia
Wikipedia is a free content, free Online content, online encyclopedia that is written and maintained by a community of volunteers, known as Wikipedians, through open collaboration and the wiki software MediaWiki. Founded by Jimmy Wales and La ...
has been plagiarized and used in violation of the GFDL by other sites, such as
Baidu Baike, no contributors have ever tried to bring an organization to court due to violation of the GFDL. In the case of Baidu, Wikipedia representatives asked the site and its contributors to respect the terms of the licenses and to make proper attributions.
Criticism
Some critics consider the GFDL a non-free license. Some reasons for this are that the GFDL allows "invariant" text which cannot be modified or removed, and that its prohibition against
digital rights management
Digital rights management (DRM) is the management of legal access to digital content. Various tools or technological protection measures, such as access control technologies, can restrict the use of proprietary hardware and copyrighted works. DRM ...
(DRM) systems applies to valid usages, like for "private copies made and not distributed".
Notably, the
Debian
Debian () is a free and open-source software, free and open source Linux distribution, developed by the Debian Project, which was established by Ian Murdock in August 1993. Debian is one of the oldest operating systems based on the Linux kerne ...
project,
Thomas Bushnell,
Nathanael Nerode,
and
Bruce Perens have raised objections. Bruce Perens saw the GFDL even outside the "Free Software ethos":
In 2006, Debian developers voted to consider works licensed under the GFDL to comply with their
Debian Free Software Guidelines provided that the invariant section clauses are not used.
[Debian:]
General Resolution: Why the GNU Free Documentation License is not suitable for Debian main – Amendment Text A
. 2006. (Accessed June 20, 2009) However, their resolution stated that even without invariant sections, GFDL-licensed software documentation is considered to be "still not free of trouble" by the project, namely because of its incompatibility with the major free software licenses.
[
Those opposed to the GFDL have recommended the use of alternative licenses such as the BSD License or the GNU GPL.][
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, citing the incompatibility between the two, difficulties in implementing the GFDL, and the fact that the GFDL "does not allow for easy duplication and modification", especially for digital documentation.
]
DRM clause
The GNU FDL contains the statement:
A criticism of this language is that it is too broad, because it applies to private copies made but not distributed. This means that a licensee is not allowed to save document copies "made" in a proprietary file format or using encryption.
In 2003, Richard Stallman said about the above sentence on the debian-legal mailing list:
Invariant sections
A GNU FDL work can quickly be encumbered because a new, different title must be given and a list of previous titles must be kept. This could lead to the situation where there are a whole series of title pages, and dedications, in each and every copy of the book if it has a long lineage. These pages cannot be removed until the work enters the public domain
The public domain (PD) consists of all the creative work to which no Exclusive exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly Waiver, waived, or may be inapplicable. Because no one holds ...
after copyright
A copyright is a type of intellectual property that gives its owner the exclusive legal right to copy, distribute, adapt, display, and perform a creative work, usually for a limited time. The creative work may be in a literary, artistic, ...
expires.
Richard Stallman said about invariant sections on the ''debian-legal'' mailing list:
GPL incompatible in both directions
The GNU FDL is incompatible in both directions with the GPL—material under the GNU FDL cannot be put into GPL code and GPL code cannot be put into a GNU FDL manual. At the June 22–23, 2006 international GPLv3 conference in Barcelona, Eben Moglen hinted that a future version of the GPL could be made suitable for documentation:
Burdens when printing
The GNU FDL requires that licensees, when printing a document covered by the license, must also include "this License, the copyright notices, and the license notice saying this License applies to the Document". This means that if a licensee prints out a copy of an article whose text is covered under the GNU FDL, they must also include a copyright notice and a physical printout of the GNU FDL, which is a significantly large document in itself. Worse, the same is required for the standalone use of just one (for example, Wikipedia) image. Several Wikimedia projects have over the years abandoned the use of GFDL, among them the English Wikipedia, which has relicensed the files. Wikivoyage, a web site dedicated to free content travel guides, chose not to use the GFDL from the beginning because it considers it unsuitable for short printed texts.
Other licenses for free works
* Creative Commons license
A Creative Commons (CC) license is one of several public copyright licenses that enable the free distribution of an otherwise copyrighted "work". A CC license is used when an author wants to give other people the right to share, use, and bu ...
* Design Science License
* Free Art License
* FreeBSD Documentation License
* Open Content License
* Open Game License
* Open Publication License
* WTFPL
List of projects that use the GFDL
* Most projects of the Wikimedia Foundation
The Wikimedia Foundation, Inc. (WMF) is an American 501(c)(3) nonprofit organization headquartered in San Francisco, California, and registered there as foundation (United States law), a charitable foundation. It is the host of Wikipedia, th ...
, including Wikipedia
Wikipedia is a free content, free Online content, online encyclopedia that is written and maintained by a community of volunteers, known as Wikipedians, through open collaboration and the wiki software MediaWiki. Founded by Jimmy Wales and La ...
(excluding Wikivoyage and Wikinews
Wikinews is a free-content news wiki and a Wikimedia project, project of the Wikimedia Foundation that works through collaborative journalism through user-created content. Wikipedia co-founder Jimmy Wales has distinguished Wikinews from Wikipe ...
) – On June 15, 2009, the Section 11 clauses were used to dual-license the content of these wikis under the Creative Commons Attribution Share-Alike license and GFDL.
* An Anarchist FAQ
* Citizendium – the project uses GFDL for articles originally from Wikipedia.
* Free On-line Dictionary of Computing
* Last.fm – artist descriptions are under GFDL
* Marxists Internet Archive
* PlanetMath
PlanetMath is a free content, free, collaborative, mathematics online encyclopedia. Intended to be comprehensive, the project is currently hosted by the University of Waterloo. The site is owned by a US-based nonprofit corporation, "PlanetMath.org ...
(now uses CC BY-SA license)
* Rosetta Code
* SourceWatch
* The specification documents that define TRAK, an enterprise architecture framework, are released under the GFDL.
* ''Abstract Algebra'' by Thomas W. Judson.
* the Baseball-Reference
Baseball Reference is a baseball statistics database maintained by Sports Reference. The site provides career statistics for Major League Baseball (MLB) players and teams as well as records, MLB draft history, and sabermetrics.
History
Founde ...
's BR Bullpen, a free user-contributed baseball wiki
See also
* BSD licenses
* Copyleft
* Copyright
A copyright is a type of intellectual property that gives its owner the exclusive legal right to copy, distribute, adapt, display, and perform a creative work, usually for a limited time. The creative work may be in a literary, artistic, ...
* Free-software license
A free-software license is a notice that grants the recipient of a piece of software extensive rights to modify and software distribution, redistribute that software. These actions are usually prohibited by copyright law, but the rights-holde ...
* GNU
* Non-commercial educational station
* Free content
* Share-alike
* Software license
A software license is a legal instrument governing the use or redistribution of software.
Since the 1970s, software copyright has been recognized in the United States. Despite the copyright being recognized, most companies prefer to sell lic ...
References
External links
*
GNU Free Documentation License v1.3
��This version is deprecated by the FSF.
GNU Free Documentation License v1.1
��This version is deprecated by the FSF.
FSF guide to the new drafts of documentation licenses
essay by Richard Stallman
Apple's Common Documentation License
, an alternative license
{{DEFAULTSORT:Gnu Free Documentation License
GNU Project
Free content licenses
Software documentation
Copyleft
Free Software Foundation
Free and open-source software licenses
Copyleft software licenses