Discussion Draft 1 of Version 3, 16 Jan 2006


Copyright (C) 2006 Free Software Foundation, Inc.
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.


The licenses for most software are designed to take away your freedom to share and change it. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change free software--to make sure the software is free for all its users. We, the Free Software Foundation, use the GNU General Public License for most of our software; it applies also to any other program whose authors commit to using it. (Some Free Software Foundation software is covered by the GNU Lesser General Public License instead.) You can apply it to your programs, too. ¶

When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for this service if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs; and that you know you can do these things. ¶

To protect your rights, we need to make requirements that forbid anyone to deny you these rights or to ask you to surrender the rights. These restrictions translate to certain responsibilities for you if you distribute copies of the software, or if you modify it. ¶

For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights. ¶

Developers that use the GNU GPL protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License which gives you legal permission to copy, distribute and/or modify the software. ¶

For the developers' and author's protection, the GPL clearly explains that there is no warranty for this free software. If the software is modified by someone else and passed on, the GPL ensures that recipients are told that what they have is not the original, so that any problems introduced by others will not reflect on the original authors' reputations. ¶

Some countries have adopted laws prohibiting software that enables users to escape from Digital Restrictions Management. DRM is fundamentally incompatible with the purpose of the GPL, which is to protect users' freedom; therefore, the GPL ensures that the software it covers will neither be subject to, nor subject other works to, digital restrictions from which escape is forbidden. ¶

Finally, every program is threatened constantly by software patents. We wish to avoid the special danger that redistributors of a free program will individually obtain patent licenses, in effect making the program proprietary. To prevent this, the GPL makes it clear that any patent must be licensed for everyone's free use or not licensed at all. ¶

The precise terms and conditions for copying, distribution and modification follow. ¶



0. Definitions. ¶

A "licensed program" means any program or other work distributed under this License. The "Program" refers to any such program or work, and a "work based on the Program" means either the Program or any derivative work under copyright law: that is to say, a work containing the Program or a portion of it, either modified or unmodified. Throughout this License, the term "modification" includes, without limitation, translation and extension. A "covered work" means either the Program or any work based on the Program. Each licensee is addressed as "you". ¶

To "propagate" a work means doing anything with it that requires permission under applicable copyright law, other than executing it on a computer or making private modifications. This includes copying, distribution (with or without modification), sublicensing, and in some countries other activities as well. ¶

1. Source Code. ¶

The "source code" for a work means the preferred form of the work for making modifications to it. "Object code" means any non-source version of a work. ¶

The "Complete Corresponding Source Code" for a work in object code form means all the source code needed to understand, adapt, modify, compile, link, install, and run the work, excluding general-purpose tools used in performing those activities but which are not part of the work. For example, this includes any scripts used to control those activities, and any shared libraries and dynamically linked subprograms that the work is designed to require, such as by intimate data communication or control flow between those subprograms and other parts of the work, and interface definition files associated with the program source files. ¶

Complete Corresponding Source Code also includes any encryption or authorization codes necessary to install and/or execute the source code of the work, perhaps modified by you, in the recommended or principal context of use, such that its functioning in all circumstances is identical to that of the work, except as altered by your modifications. It also includes any decryption codes necessary to access or unseal the work's output. Notwithstanding this, a code need not be included in cases where use of the work normally implies the user already has it. ¶

Complete Corresponding Source Code need not include anything that users can regenerate automatically from other parts of the Complete Corresponding Source Code. ¶

As a special exception, the Complete Corresponding Source Code need not include a particular subunit if (a) the identical subunit is normally included as an adjunct in the distribution of either a major essential component (kernel, window system, and so on) of the operating system on which the executable runs or a compiler used to produce the executable or an object code interpreter used to run it, and (b) the subunit (aside from possible incidental extensions) serves only to enable use of the work with that system component or compiler or interpreter, or to implement a widely used or standard interface, the implementation of which requires no patent license not already generally available for software under this License. ¶

2. Basic Permissions. ¶

All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met. This License explicitly affirms your unlimited permission to run the Program. The output from running it is covered by this License only if the output, given its content, constitutes a work based on the Program. This License acknowledges your rights of "fair use" or other equivalent, as provided by copyright law. ¶

This License gives unlimited permission to privately modify and run the Program, provided you do not bring suit for patent infringement against anyone for making, using or distributing their own works based on the Program. ¶

Propagation of covered works is permitted without limitation provided it does not enable parties other than you to make or receive copies. Propagation which does enable them to do so is permitted, as "distribution", under the conditions of sections 4-6 below. ¶

3. Digital Restrictions Management. ¶

As a free software license, this License intrinsically disfavors technical attempts to restrict users' freedom to copy, modify, and share copyrighted works. Each of its provisions shall be interpreted in light of this specific declaration of the licensor's intent. Regardless of any other provision of this License, no permission is given to distribute covered works that illegally invade users' privacy, nor for modes of distribution that deny users that run covered works the full exercise of the legal rights granted by this License. ¶

No covered work constitutes part of an effective technological protection measure: that is to say, distribution of a covered work as part of a system to generate or access certain data constitutes general permission at least for development, distribution and use, under this License, of other software capable of accessing the same data. ¶

4.[1] Verbatim Copying. ¶

You may copy and distribute verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all license notices and notices of the absence of any warranty; give all recipients of the Program a copy of this License along with the Program; and obey any additional terms present on parts of the Program in accord with section 7. ¶

You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection for a fee. ¶

5.[2] Distributing Modified Source Versions. ¶

Having modified a copy of the Program under the conditions of section 2, thus forming a work based on the Program, you may copy and distribute such modifications or work in the form of source code under the terms of Section 4 above, provided that you also meet all of these conditions: ¶

a) The modified work must carry prominent notices stating that you changed the work and the date of any change. ¶

b) You must license the entire modified work, as a whole, under this License to anyone who comes into possession of a copy. This License must apply, unmodified except as permitted by section 7 below, to the whole of the work. 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. ¶

c) If the modified work has interactive user interfaces, each must include a convenient feature that displays an appropriate copyright notice, and tells the user that there is no warranty for the program (or that you provide a warranty), that users may redistribute the modified work under these conditions, and how to view a copy of this License together with the central list (if any) of other terms in accord with section 7. If the interface presents a list of user commands or options, such as a menu, a command to display this information must be prominent in the list. Otherwise, the modified work must display this information at startup--except in the case that the Program has such interactive modes and does not display this information at startup. ¶

These requirements apply to the modified work as a whole. If identifiable sections of that work, added by you, 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 for use not in combination with the Program. But when you distribute the same sections for use in combination with covered works, no matter in what form such combination occurs, the whole of the combination must be licensed under this License, whose permissions for other licensees extend to the entire whole, and thus to every part of the whole. Your sections may carry other terms as part of this combination in limited ways, described in section 7. ¶

Thus, it is not the intent of this section to claim rights or contest your rights to work written entirely by you; rather, the intent is to exercise the right to control the distribution of derivative or collective works based on the Program. ¶

A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, in or on a volume of a storage or distribution medium, is called an "aggregate" if the copyright resulting from the compilation is not used to limit the legal rights of the compilation's users beyond what the individual works permit. Mere inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate. ¶

6.[3] Non-Source Distribution. ¶

You may copy and distribute a covered work in Object Code form under the terms of Sections 4 and 5, provided that you also distribute the machine-readable Complete Corresponding Source Code (herein the "Corresponding Source") under the terms of this License, in one of these ways: ¶

a) Distribute the Object Code in a physical product (including a physical distribution medium), accompanied by the Corresponding Source distributed on a durable physical medium customarily used for software interchange; or, ¶

b) Distribute the Object Code in a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give any third party, for a price no more than ten times your cost of physically performing source distribution, a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange; or, ¶

c) Privately distribute the Object Code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only for occasional noncommercial distribution, and only if you received the Object Code with such an offer, in accord with Subsection b above. Or, ¶

d) Distribute the Object Code by offering access to copy it from a designated place, and offer equivalent access to copy the Corresponding Source in the same way through the same place. You need not require recipients to copy the Corresponding Source along with the Object Code. ¶

[If the place to copy the Object Code is a network server, the Corresponding Source may be on a different server that supports equivalent copying facilities, provided you have explicitly arranged with the operator of that server to keep the Corresponding Source available for as long as needed to satisfy these requirements, and provided you maintain clear directions next to the Object Code saying where to find the Corresponding Source.] ¶

Distribution of the Corresponding Source in accord with this section must be in a format that is publicly documented, unencumbered by patents, and must require no special password or key for unpacking, reading or copying. ¶

The Corresponding Source may include portions which do not formally state this License as their license, but qualify under section 7 for inclusion in a work under this License. ¶

7. License Compatibility. ¶

When you release a work based on the Program, you may include your own terms covering added parts for which you have, or can give, appropriate copyright permission, as long as those terms clearly permit all the activities that this License permits, or permit usage or relicensing under this License. Your terms may be written separately or may be this License plus additional written permission. If you so license your own added parts, those parts may be used separately under your terms, but the entire work remains under this License. Those who copy the work, or works based on it, must preserve your terms just as they must preserve this License, as long as any substantial portion of the parts they apply to are present. ¶

Aside from additional permissions, your terms may add limited kinds of additional requirements on your added parts, as follows: ¶

a) They may require the preservation of certain copyright notices, other legal notices, and/or author attributions, and may require that the origin of the parts they cover not be misrepresented, and/or that altered versions of them be marked in the source code, or marked there in specific reasonable ways, as different from the original version. ¶

b) They may state a disclaimer of warranty and liability in terms different from those used in this License. ¶

c) They may prohibit or limit the use for publicity purposes of specified names of contributors, and they may require that certain specified trademarks be used for publicity purposes only in the ways that are fair use under trademark law except with express permission. ¶

d) They may require that the work contain functioning facilities that allow users to immediately obtain copies of its Complete Corresponding Source Code. ¶

e) They may impose software patent retaliation, which means permission for use of your added parts terminates or may be terminated, wholly or partially, under stated conditions, for users closely related to any party that has filed a software patent lawsuit (i.e., a lawsuit alleging that some software infringes a patent). The conditions must limit retaliation to a subset of these two cases: 1. Lawsuits that lack the justification of retaliating against other software patent lawsuits that lack such justification. 2. Lawsuits that target part of this work, or other code that was elsewhere released together with the parts you added, the whole being under the terms used here for those parts. ¶

No other additional conditions are permitted in your terms; therefore, no other conditions can be present on any work that uses this License. This License does not attempt to enforce your terms, or assert that they are valid or enforceable by you; it simply does not prohibit you from employing them. ¶

When others modify the work, if they modify your parts of it, they may release such parts of their versions under this License without additional permissions, by including notice to that effect, or by deleting the notice that gives specific permissions in addition to this License. Then any broader permissions granted by your terms which are not granted by this License will not apply to their modifications, or to the modified versions of your parts resulting from their modifications. However, the specific requirements of your terms will still apply to whatever was derived from your added parts. ¶

Unless the work also permits distribution under a previous version of this License, all the other terms included in the work under this section must be listed, together, in a central list in the work. ¶

8.[4] Termination. ¶

You may not propagate, modify or sublicense the Program except as expressly provided under this License. Any attempt otherwise to propagate, modify or sublicense the Program is void, and any copyright holder may terminate your rights under this License at any time after having notified you of the violation by any reasonable means within 60 days of any occurrence. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as they remain in full compliance. ¶

9.[5] Not a Contract. You are not required to accept this License in order to receive a copy of the Program. However, nothing else grants you permission to propagate or modify the Program or any covered works. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating the Program (or any covered work), you indicate your acceptance of this License to do so, and all its terms and conditions. ¶

10.[6] Automatic Licensing of Downstream Users. ¶

Each time you redistribute a covered work, the recipient automatically receives a license from the original licensors, to propagate and modify that work, subject to this License, including any additional terms introduced through section 7. You may not impose any further restrictions on the recipients' exercise of the rights thus granted or affirmed, except (when modifying the work) in the limited ways permitted by section 7. You are not responsible for enforcing compliance by third parties to this License. ¶

11. Licensing of Patents. ¶

When you distribute a covered work, you grant a patent license to the recipient, and to anyone that receives any version of the work, permitting, for any and all versions of the covered work, all activities allowed or contemplated by this License, such as installing, running and distributing versions of the work, and using their output. This patent license is nonexclusive, royalty-free and worldwide, and covers all patent claims you control or have the right to sublicense, at the time you distribute the covered work or in the future, that would be infringed or violated by the covered work or any reasonably contemplated use of the covered work. ¶

If you distribute a covered work knowingly relying on a patent license, you must act to shield downstream users against the possible patent infringement claims from which your license protects you. ¶

12.[7] Liberty or Death for the Program. ¶

If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot distribute the Program, or other covered work, so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not distribute it at all. For example, if a patent license would not permit royalty-free redistribution by all those who receive copies directly or indirectly through you, then the only way you could satisfy both it and this License would be to refrain entirely from distribution. ¶

It is not the purpose of this section to induce you to infringe any patents or other exclusive rights or to contest their legal validity. The sole purpose of this section is to protect the integrity of the free software distribution system. Many people have made generous contributions to the wide range of software distributed through that system in reliance on consistent application of that system; it is up to the author/donor to decide if he or she is willing to distribute software through any other system and a licensee cannot impose that choice. ¶

[13.[8] Geographical Limitations. ¶

If the distribution and/or use of the Program is restricted in certain countries either by patents or by copyrighted interfaces, the original copyright holder who places the Program under this License may add an explicit geographical distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus excluded. In such case, this License incorporates the limitation as if written in the body of this License.] ¶

14.[9] Revised Versions of this License. ¶

The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. ¶

Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation. ¶

15.[10] Requesting Exceptions. ¶

If you wish to incorporate parts of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally. ¶


16.[11] There is no warranty for the Program, to the extent permitted by applicable law. Except when otherwise stated in writing the copyright holders and/or other parties provide the Program "as is" without warranty of any kind, either expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. The entire risk as to the quality and performance of the Program is with you. Should the Program prove defective, you assume the cost of all necessary servicing, repair or correction. ¶

17.[12] In no event unless required by applicable law or agreed to in writing will any copyright holder, or any other party who may modify and/or redistribute the Program as permitted above, be liable to you for damages, including any general, special, incidental or consequential damages arising out of the use or inability to use the Program (including but not limited to loss of data or data being rendered inaccurate or losses sustained by you or third parties or a failure of the Program to operate with any other programs), even if such holder or other party has been advised of the possibility of such damages. ¶

18. Unless specifically stated, the Program has not been tested for use in safety critical systems. ¶


How to Apply These Terms to Your New Programs ¶

If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms. ¶

To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found. ¶

<one line to give the program's name and a brief idea of what it does.> Copyright (C) <year> <name of author> ¶

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. ¶

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. ¶

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA ¶

Also add information on how to contact you by electronic and paper mail. ¶

If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode: ¶

Gnomovision version 69, Copyright (C) year name of author Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. ¶

The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than `show w' and `show c'; for a GUI interface, you would use an "About box" instead. ¶

You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names: ¶

Yoyodyne, Inc., hereby disclaims all copyright interest in the program `Gnomovision' (which makes passes at compilers) written by James Hacker. ¶

<signature of Rich R. Thanus>, 1 April 1989 Rich R. Thanus, Peripheral Visionary ¶

For more information on how to apply and follow the GNU GPL, see ¶

The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License. ¶

Copyright © 2006 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. Verbatim copying and distribution of this entire article are permitted worldwide, without royalty, in any medium, provided this notice, and the copyright notice, are preserved. Distributed under the GNU GPL license.