Лицензия для вашего open-source проекта

В этой статье я хочу немного поговорить об авторском праве и свободных лицензиях на ПО. Текст является результатом самостоятельного выбора лицензий и их применения к своим проектам.

Статья будет полезна тем, кто хочет:

— в общих чертах понять, что такое авторское право (но лучше обратиться к юристу);
— подобрать свободную лицензию для своего проекта;
— разобраться, что нужно писать в шапке файла исходного кода.

Первым делом — ссылка на LicenseIT, очень полезный сайт с описанием лицензий и особенностей их применения (в том числе в России), который я умудрился не найти при подготовке статьи. Исправляюсь. Спасибо sensboston за ссылку.

• Авторское право
• Свободные лицензии
  
  • GNU GPL Version 3
  • GNU GPL Version 2
  • GNU LGPL
  • GNU AGPL
  • MPL Version 2.0
  • EPL Version 1.0
  • Ms-PL
  • MIT
  • Apache 2.0
  • BSD
  • WTFPL
  • Beerware
  • Общественное достояние
  • CC0
  • Unlicense
• Copyright в исходниках
• Заключение
• Материалы

Авторское право

Для начала коротко о том, что вообще такое авторское право и лицензии.

Meanwhile in Russia

Если вы в качестве результата интеллектуальной деятельности создали некое произведение (например, программу), то в этом случае вы — его автор(ы). Вы обладаете имущественными и неимущественными правами на это произведение. Имущественные права на это произведение вы можете передать и кому-то другому, но передать неимущественные, в том числе авторство, у вас уже не получится. Быть автором — это ваше неотчуждаемое и непередаваемое право.

Даже если вы при создании произведения работали «на дядю», то и в этом случае автор вовсе не некое абстрактное ООО. Возможно, когда вы устраивались на работу, то подписывали в том числе и пункт про «отчуждение исключительных прав на результаты вашей интеллектуальной деятельности в пользу работодателя» в договоре или что-то подобное. Возможно, нет (в этом случае гуглите "Служебное произведение"). В обоих случаях автор — вы. И обладаете некоторыми правами.

Лицензии

Другой способ передачи прав на произведение — лицензия. В этом случае права не отчуждаются, они передаются в соответствии с тем, что прописано в лицензионном договоре между пользователем и правообладателем. Да, лицензия — это именно договор! Все лицензии на ПО, как коммерческие, так и свободные, представляют из себя такой договор. В нем прописано, что вы можете и что не можете делать с ПО, и как далеко вас может послать правообладатель в случае претензий. Например, лицензия может дать вам право устанавливать программу, но ограничивать это право только одним компьютером, иначе к вам приедут дяди в масках и все отберут.

Обратите внимание на важный момент: если у вас достаточно прав на произведение, то вы можете распространять его под разными лицензиями (в том числе, одновременно). Например, на вашем сайте вы можете распространять программу бесплатно под свободной лицензией, а в каком-либо магазине приложений она может продаваться за деньги под их стандартной лицензией.

Также Вы можете сменить лицензию в любое время: например, сегодня у вас на сайте программа была бесплатной под свободной лицензией, а завтра она платная и с закрытыми исходниками. Но в этом случае вы не можете заставить пользователей, скачавших программу ранее, следовать нормам новой лицензии. Это логично, ведь они получили программу по другому договору.

В мире

В целом, вышеописанное применимо к большинству стран мира. Дело в том, что благодаря нескольким международным конвенциям, законы об авторском праве в мире схожи (но есть и некоторое число стран, не подписывавших конвенции). Однако, даже при этом отличия существуют. Например, в России неимущественные права не отчуждаются. А, скажем, в Канаде можно от них отказаться, но нельзя передать. Поэтому при возможности лучше всегда консультироваться с локальным юристом.

Свободные лицензии

Определяем определение

За поиском определения я отправлю желающих на Википедию, для чего дам ссылки сразу на несколько статей:

• Лицензия на программное обеспечение
• Определение свободного программного обеспечения
• Критерии Debian по определению свободного программного обеспечения
• Свободная лицензия
• Проприетарное программное обеспечение

Это не потому, что я такой злой (хотя, велосипед у меня действительно отсутствует), а потому, что для термина свободная лицензия пока нет однозначного определения. Из указанных статей можно вывести примерно следующее:

Свободной лицензией является лицензия, которая соответствует неким критериям свободного ПО. Обычно используют либо определение свободного ПО, данное Ричардом Столлманом, либо критерии Debian по определению свободного программного обеспечения, сформулированные Брюсом Перенсом. Соответственно, те лицензии, которые не являются свободными — несвободные.

На мой личный взгляд, заморачиваться с конкретными определениями нет никакого смысла, мы ведь не политики (ну, по крайней мере, я). А с практической точки зрения, основная разница между свободными и несвободными лицензиями — в целях. Несвободные лицензии применяются с целью заработать и не дать на этом заработать конкурентам, свободные — с целью предоставить возможность безвозмездно пользоваться плодами вашего труда.

Copyleft

Перед тем как приступить к описанию лицензий, нужно разобраться, что такое копилефтные и разрешительные (пермиссивные, permissive) лицензии. Копилефтными считаются свободные лицензии, требующие распространять производные продукты под такой же лицензией. То есть, если вы использовали в своей программе библиотеку под копилефтной лицензией, то вам придется распространять вашу программу под ней же. Задача же разрешительных лицензий, напротив, разрешить любое возможное использование продукта.

Основные свободные лицензии

Большой список свободных лицензий можно найти на сайте GNU.
Также, sensboston дал ссылку на еще один список с open-source лицензиями.
Здесь же я приведу список лицензий, в которому будут те лицензии, которые я считаю наиболее полезными и/или значимыми, и те, написать про которые вы предложили в комментариях.

GPLv3 (GNU General Public License Version 3)

Текст лицензии

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run a copy of the Program.  Ancillary propagation of a covered work
occurring solely as a consequence of using peer-to-peer transmission
to receive a copy likewise does not require acceptance.  However,
nothing other than this License grants you permission to propagate or
modify any covered work.  These actions infringe copyright if you do
not accept this License.  Therefore, by modifying or propagating a
covered work, you indicate your acceptance of this License to do so.

  10. Automatic Licensing of Downstream Recipients.

  Each time you convey a covered work, the recipient automatically
receives a license from the original licensors, to run, modify and
propagate that work, subject to this License.  You are not responsible
for enforcing compliance by third parties with this License.

  An "entity transaction" is a transaction transferring control of an
organization, or substantially all assets of one, or subdividing an
organization, or merging organizations.  If propagation of a covered
work results from an entity transaction, each party to that
transaction who receives a copy of the work also receives whatever
licenses to the work the party's predecessor in interest had or could
give under the previous paragraph, plus a right to possession of the
Corresponding Source of the work from the predecessor in interest, if
the predecessor has it or can get it with reasonable efforts.

  You may not impose any further restrictions on the exercise of the
rights granted or affirmed under this License.  For example, you may
not impose a license fee, royalty, or other charge for exercise of
rights granted under this License, and you may not initiate litigation
(including a cross-claim or counterclaim in a lawsuit) alleging that
any patent claim is infringed by making, using, selling, offering for
sale, or importing the Program or any portion of it.

  11. Patents.

  A "contributor" is a copyright holder who authorizes use under this
License of the Program or a work on which the Program is based.  The
work thus licensed is called the contributor's "contributor version".

  A contributor's "essential patent claims" are all patent claims
owned or controlled by the contributor, whether already acquired or
hereafter acquired, that would be infringed by some manner, permitted
by this License, of making, using, or selling its contributor version,
but do not include claims that would be infringed only as a
consequence of further modification of the contributor version.  For
purposes of this definition, "control" includes the right to grant
patent sublicenses in a manner consistent with the requirements of
this License.

  Each contributor grants you a non-exclusive, worldwide, royalty-free
patent license under the contributor's essential patent claims, to
make, use, sell, offer for sale, import and otherwise run, modify and
propagate the contents of its contributor version.

  In the following three paragraphs, a "patent license" is any express
agreement or commitment, however denominated, not to enforce a patent
(such as an express permission to practice a patent or covenant not to
sue for patent infringement).  To "grant" such a patent license to a
party means to make such an agreement or commitment not to enforce a
patent against the party.

  If you convey a covered work, knowingly relying on a patent license,
and the Corresponding Source of the work is not available for anyone
to copy, free of charge and under the terms of this License, through a
publicly available network server or other readily accessible means,
then you must either (1) cause the Corresponding Source to be so
available, or (2) arrange to deprive yourself of the benefit of the
patent license for this particular work, or (3) arrange, in a manner
consistent with the requirements of this License, to extend the patent
license to downstream recipients.  "Knowingly relying" means you have
actual knowledge that, but for the patent license, your conveying the
covered work in a country, or your recipient's use of the covered work
in a country, would infringe one or more identifiable patents in that
country that you have reason to believe are valid.

  If, pursuant to or in connection with a single transaction or
arrangement, you convey, or propagate by procuring conveyance of, a
covered work, and grant a patent license to some of the parties
receiving the covered work authorizing them to use, propagate, modify
or convey a specific copy of the covered work, then the patent license
you grant is automatically extended to all recipients of the covered
work and works based on it.

  A patent license is "discriminatory" if it does not include within
the scope of its coverage, prohibits the exercise of, or is
conditioned on the non-exercise of one or more of the rights that are
specifically granted under this License.  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 (a) in connection with copies of the covered work
conveyed by you (or copies made from those copies), or (b) primarily
for and in connection with specific products or compilations that
contain the covered work, unless you entered into that arrangement,
or that patent license was granted, prior to 28 March 2007.

  Nothing in this License shall be construed as excluding or limiting
any implied license or other defenses to infringement that may
otherwise be available to you under applicable patent law.

  12. No Surrender of Others' Freedom.

  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 convey a
covered work so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you may
not convey it at all.  For example, if you agree to terms that obligate you
to collect a royalty for further conveying from those to whom you convey
the Program, the only way you could satisfy both those terms and this
License would be to refrain entirely from conveying the Program.

  13. Use with the GNU Affero General Public License.

  Notwithstanding any other provision of this License, you have
permission to link or combine any covered work with a work licensed
under version 3 of the GNU Affero General Public License into a single
combined work, and to convey the resulting work.  The terms of this
License will continue to apply to the part which is the covered work,
but the special requirements of the GNU Affero General Public License,
section 13, concerning interaction through a network will apply to the
combination as such.

  14. 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 the GNU General
Public 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 the
GNU General Public License, you may choose any version ever published
by the Free Software Foundation.

  If the Program specifies that a proxy can decide which future
versions of the GNU General Public License can be used, that proxy's
public statement of acceptance of a version permanently authorizes you
to choose that version for the Program.

  Later license versions may give you additional or different
permissions.  However, no additional obligations are imposed on any
author or copyright holder as a result of your choosing to follow a
later version.

  15. Disclaimer of Warranty.

  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.

  16. Limitation of Liability.

  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
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.

  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
an absolute waiver of all civil liability in connection with the
Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.

                     END OF TERMS AND CONDITIONS

            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
state 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, see <http://www.gnu.org/licenses/>.

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:

    <program>  Copyright (C) <year>  <name of author>
    This program 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, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<http://www.gnu.org/licenses/>.

  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.  But first, please read
<http://www.gnu.org/philosophy/why-not-lgpl.html>.

Как применять лицензии GNU со своими программами
Практическое руководство по соответствию GPL, спасибо Indexator за ссылку.
GNU GPL 3 человеческим языком, еще раз спасибо Indexator.
Самая известная из свободных лицензий. Не в том смысле, что все хорошо ее понимают, а в том, что она более всего на слуху. Так как она называется свободной, многие ошибочно считают, что код, выпущенный под GPL, можно использовать как угодно, а программы могут/должны быть только бесплатными. И то, и другое — неправда. GNU GPL — копилефтная лицензия, и требует, чтобы исходные коды производных работ были открытыми под ней же. То есть, если вы решите использовать библиотеку под GPL в вашем проекте, вам придется выложить исходники вашего проекта под GPL, что обычно неприемлемо для коммерческих разработок вам придется бесплатно предоставлять исходники проекта конечным получателям, даже если вы распространяете продукт за деньги (спасибо хабраюзеру coh за указание на неточность). Да, продажа программы лицензией вполне разрешена. Предоставлять исходники можно как вместе с программой, так и отдельно. Во втором случае бинарная версия программы должна содержать четкие инструкции по получению исходных кодов. Более подробные объяснения — перевод части официальногоGPL FAQ(еще раз спасибо, coh !).

GPLv2 (GNU General Public License Version 2)

Текст лицензии

                    GNU GENERAL PUBLIC LICENSE
                       Version 2, June 1991

 Copyright (C) 1989, 1991 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.

                            Preamble

  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.  This
General Public License applies to most of the Free Software
Foundation's software and to any other program whose authors commit to
using it.  (Some other 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 restrictions 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.

  We protect your rights with two steps: (1) copyright the software, and
(2) offer you this license which gives you legal permission to copy,
distribute and/or modify the software.

  Also, for each author's protection and ours, we want to make certain
that everyone understands that there is no warranty for this free
software.  If the software is modified by someone else and passed on, we
want its recipients to know that what they have is not the original, so
that any problems introduced by others will not reflect on the original
authors' reputations.

  Finally, any free program is threatened constantly by software
patents.  We wish to avoid the danger that redistributors of a free
program will individually obtain patent licenses, in effect making the
program proprietary.  To prevent this, we have made 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.

                    GNU GENERAL PUBLIC LICENSE
   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

  0. This License applies to any program or other work which contains
a notice placed by the copyright holder saying it may be distributed
under the terms of this General Public License.  The "Program", below,
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 verbatim or with modifications and/or translated into another
language.  (Hereinafter, translation is included without limitation in
the term "modification".)  Each licensee is addressed as "you".

Activities other than copying, distribution and modification are not
covered by this License; they are outside its scope.  The act of
running the Program is not restricted, and the output from the Program
is covered only if its contents constitute a work based on the
Program (independent of having been made by running the Program).
Whether that is true depends on what the Program does.

  1. 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 and disclaimer of warranty; keep intact all the
notices that refer to this License and to the absence of any warranty;
and give any other recipients of the Program a copy of this License
along with the Program.

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

  2. 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:

    a) You must cause the modified files to carry prominent notices
    stating that you changed the files and the date of any change.

    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.

    c) If the modified program normally reads commands interactively
    when run, you must cause it, when started running for such
    interactive use in the most ordinary way, to print or display an
    announcement including an appropriate copyright notice and a
    notice that there is no warranty (or else, saying that you provide
    a warranty) and that users may redistribute the program under
    these conditions, and telling the user how to view a copy of this
    License.  (Exception: if the Program itself is interactive but
    does not normally print such an announcement, your work based on
    the Program is not required to print an announcement.)

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.

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.

In addition, mere aggregation of another work not based on the Program
with the Program (or with a work based on the Program) on a volume of
a storage or distribution medium does not bring the other work under
the scope of this License.

  3. You may copy and distribute the Program (or a work based on it,
under Section 2) in object code or executable form under the terms of
Sections 1 and 2 above provided that you also do one of the following:

    a) Accompany it with the complete corresponding machine-readable
    source code, which must be distributed under the terms of Sections
    1 and 2 above on a medium customarily used for software interchange; or,

    b) Accompany it with a written offer, valid for at least three
    years, to give any third party, for a charge no more than your
    cost of physically performing source distribution, a complete
    machine-readable copy of the corresponding source code, to be
    distributed under the terms of Sections 1 and 2 above on a medium
    customarily used for software interchange; or,

    c) Accompany it with the information you received as to the offer
    to distribute corresponding source code.  (This alternative is
    allowed only for noncommercial distribution and only if you
    received the program in object code or executable form with such
    an offer, in accord with Subsection b above.)

The source code for a work means the preferred form of the work for
making modifications to it.  For an executable work, complete source
code means all the source code for all modules it contains, plus any
associated interface definition files, plus the scripts used to
control compilation and installation of the executable.  However, as a
special exception, the source code distributed need not include
anything that is normally distributed (in either source or binary
form) with the major components (compiler, kernel, and so on) of the
operating system on which the executable runs, unless that component
itself accompanies the executable.

If distribution of executable or object code is made by offering
access to copy from a designated place, then offering equivalent
access to copy the source code from the same place counts as
distribution of the source code, even though third parties are not
compelled to copy the source along with the object code.

  4. You may not copy, modify, sublicense, or distribute the Program
except as expressly provided under this License.  Any attempt
otherwise to copy, modify, sublicense or distribute the Program is
void, and will automatically terminate your rights under this License.
However, parties who have received copies, or rights, from you under
this License will not have their licenses terminated so long as such
parties remain in full compliance.

  5. You are not required to accept this License, since you have not
signed it.  However, nothing else grants you permission to modify or
distribute the Program or its derivative works.  These actions are
prohibited by law if you do not accept this License.  Therefore, by
modifying or distributing the Program (or any work based on the
Program), you indicate your acceptance of this License to do so, and
all its terms and conditions for copying, distributing or modifying
the Program or works based on it.

  6. Each time you redistribute the Program (or any work based on the
Program), the recipient automatically receives a license from the
original licensor to copy, distribute or modify the Program subject to
these terms and conditions.  You may not impose any further
restrictions on the recipients' exercise of the rights granted herein.
You are not responsible for enforcing compliance by third parties to
this License.

  7. If, as a consequence of a court judgment or allegation of patent
infringement or for any other reason (not limited to patent issues),
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 so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you
may not distribute the Program at all.  For example, if a patent
license would not permit royalty-free redistribution of the Program 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 of the Program.

If any portion of this section is held invalid or unenforceable under
any particular circumstance, the balance of the section is intended to
apply and the section as a whole is intended to apply in other
circumstances.

It is not the purpose of this section to induce you to infringe any
patents or other property right claims or to contest validity of any
such claims; this section has the sole purpose of protecting the
integrity of the free software distribution system, which is
implemented by public license practices.  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.

This section is intended to make thoroughly clear what is believed to
be a consequence of the rest of this License.

  8. 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.

  9. The Free Software Foundation may publish revised and/or new versions
of the 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 a version number of this License which applies to it and "any
later version", you have the option of following the terms and conditions
either of that 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.

  10. 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.

                            NO WARRANTY

  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, 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.

  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.

                     END OF TERMS AND CONDITIONS

            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 2 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 is interactive, 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'; they could even be
mouse-clicks or menu items--whatever suits your program.

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 Ty Coon>, 1 April 1989
  Ty Coon, President of Vice

This 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.

Как применять лицензии GNU со своими программами
Практическое руководство по соответствию GPL, спасибо Indexator за ссылку.
Как резонно заметил wholeman в комментариях, не хватает описания GNU GPL версии 2. О различиях между этими двумя версиями GPL можно почитать, например, в этой статье. Также, из комментария wholeman:

GPLv3 заметно строже и может создать некоторые проблемы автору. Например, одно из требований состоит в том, что должна быть предоставлена инструкция по установке изменённого приложения на устройство. Для приложений под iOS или WindowsPhone, где нет штатной возможности установить пакет не из магазина, выполнить такое требование проблематично.

Кроме того, стоит заметить, что большинство программ, выпущенных, под GNU GPLv2, позволяют использование на условиях более поздней версии лицензии.

И, на всякий случай: таблица совместимости лицензий GNU.

LGPLv3 (GNU Lesser General Public License Version 3, в девичестве GNU Library General Public License)

Текст лицензии

                   GNU LESSER GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.


  This version of the GNU Lesser General Public License incorporates
the terms and conditions of version 3 of the GNU General Public
License, supplemented by the additional permissions listed below.

  0. Additional Definitions.

  As used herein, "this License" refers to version 3 of the GNU Lesser
General Public License, and the "GNU GPL" refers to version 3 of the GNU
General Public License.

  "The Library" refers to a covered work governed by this License,
other than an Application or a Combined Work as defined below.

  An "Application" is any work that makes use of an interface provided
by the Library, but which is not otherwise based on the Library.
Defining a subclass of a class defined by the Library is deemed a mode
of using an interface provided by the Library.

  A "Combined Work" is a work produced by combining or linking an
Application with the Library.  The particular version of the Library
with which the Combined Work was made is also called the "Linked
Version".

  The "Minimal Corresponding Source" for a Combined Work means the
Corresponding Source for the Combined Work, excluding any source code
for portions of the Combined Work that, considered in isolation, are
based on the Application, and not on the Linked Version.

  The "Corresponding Application Code" for a Combined Work means the
object code and/or source code for the Application, including any data
and utility programs needed for reproducing the Combined Work from the
Application, but excluding the System Libraries of the Combined Work.

  1. Exception to Section 3 of the GNU GPL.

  You may convey a covered work under sections 3 and 4 of this License
without being bound by section 3 of the GNU GPL.

  2. Conveying Modified Versions.

  If you modify a copy of the Library, and, in your modifications, a
facility refers to a function or data to be supplied by an Application
that uses the facility (other than as an argument passed when the
facility is invoked), then you may convey a copy of the modified
version:

   a) under this License, provided that you make a good faith effort to
   ensure that, in the event an Application does not supply the
   function or data, the facility still operates, and performs
   whatever part of its purpose remains meaningful, or

   b) under the GNU GPL, with none of the additional permissions of
   this License applicable to that copy.

  3. Object Code Incorporating Material from Library Header Files.

  The object code form of an Application may incorporate material from
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code under terms of your choice, provided that, if the incorporated
material is not limited to numerical parameters, data structure
layouts and accessors, or small macros, inline functions and templates
(ten or fewer lines in length), you do both of the following:

   a) Give prominent notice with each copy of the object code that the
   Library is used in it and that the Library and its use are
   covered by this License.

   b) Accompany the object code with a copy of the GNU GPL and this license
   document.

  4. Combined Works.

  You may convey a Combined Work under terms of your choice that,
taken together, effectively do not restrict modification of the
portions of the Library contained in the Combined Work and reverse
engineering for debugging such modifications, if you also do each of
the following:

   a) Give prominent notice with each copy of the Combined Work that
   the Library is used in it and that the Library and its use are
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   b) Accompany the Combined Work with a copy of the GNU GPL and this license
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   c) For a Combined Work that displays copyright notices during
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   d) Do one of the following:

       0) Convey the Minimal Corresponding Source under the terms of this
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       recombine or relink the Application with a modified version of
       the Linked Version to produce a modified Combined Work, in the
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       1) Use a suitable shared library mechanism for linking with the
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   e) Provide Installation Information, but only if you would otherwise
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   Application with a modified version of the Linked Version. (If
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   Information in the manner specified by section 6 of the GNU GPL
   for conveying Corresponding Source.)

  5. Combined Libraries.

  You may place library facilities that are a work based on the
Library side by side in a single library together with other library
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   a) Accompany the combined library with a copy of the same work based
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   b) Give prominent notice with the combined library that part of it
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  6. Revised Versions of the GNU Lesser General Public License.

  The Free Software Foundation may publish revised and/or new versions
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  Each version is given a distinguishing version number. If the
Library as you received it specifies that a certain numbered version
of the GNU Lesser General Public License "or any later version"
applies to it, you have the option of following the terms and
conditions either of that published version or of any later version
published by the Free Software Foundation. If the Library as you
received it does not specify a version number of the GNU Lesser
General Public License, you may choose any version of the GNU Lesser
General Public License ever published by the Free Software Foundation.

  If the Library as you received it specifies that a proxy can decide
whether future versions of the GNU Lesser General Public License shall
apply, that proxy's public statement of acceptance of any version is
permanent authorization for you to choose that version for the
Library.

Как применять лицензии GNU со своими программами
LGPL — это надстройка над GPL, и требует наличия текстов обеих лицензий в проекте. Отличие LGPL от обычной GPL заключается в том, что библиотеки под этой лицензией разрешается использовать для создания программ под другими лицензиями путем компоновки. Согласно GNU FAQ, динамическая компоновка не требует открывать исходные коды, а при статической необходимо предоставлять вашу программу в объектной форме (исходные коды не обязательны), для того чтобы пользователь мог сам изменить библиотеку и перелинковать бинарник. Впрочем, как заметил Athari, это не было обосновано в суде. GNU рекомендует применять эту лицензию только в том случае, если применение вместо нее обычной GPL приведет к тому, что библиотеку перестанут использовать, заменив на аналогичную.

GNU AGPLv3 (GNU Affero, GNU Affero General Public License Version 3)

Текст лицензии

                    GNU AFFERO GENERAL PUBLIC LICENSE
                       Version 3, 19 November 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

                            Preamble

  The GNU Affero General Public License is a free, copyleft license for
software and other kinds of works, specifically designed to ensure
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  The licenses for most software and other practical works are designed
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  When we speak of free software, we are referring to freedom, not
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  Developers that use our General Public Licenses protect your rights
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  A secondary benefit of defending all users' freedom is that
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The GNU General Public License permits making a modified version and
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  The GNU Affero General Public License is designed specifically to
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  An older license, called the Affero General Public License and
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  A contributor's "essential patent claims" are all patent claims
owned or controlled by the contributor, whether already acquired or
hereafter acquired, that would be infringed by some manner, permitted
by this License, of making, using, or selling its contributor version,
but do not include claims that would be infringed only as a
consequence of further modification of the contributor version.  For
purposes of this definition, "control" includes the right to grant
patent sublicenses in a manner consistent with the requirements of
this License.

  Each contributor grants you a non-exclusive, worldwide, royalty-free
patent license under the contributor's essential patent claims, to
make, use, sell, offer for sale, import and otherwise run, modify and
propagate the contents of its contributor version.

  In the following three paragraphs, a "patent license" is any express
agreement or commitment, however denominated, not to enforce a patent
(such as an express permission to practice a patent or covenant not to
sue for patent infringement).  To "grant" such a patent license to a
party means to make such an agreement or commitment not to enforce a
patent against the party.

  If you convey a covered work, knowingly relying on a patent license,
and the Corresponding Source of the work is not available for anyone
to copy, free of charge and under the terms of this License, through a
publicly available network server or other readily accessible means,
then you must either (1) cause the Corresponding Source to be so
available, or (2) arrange to deprive yourself of the benefit of the
patent license for this particular work, or (3) arrange, in a manner
consistent with the requirements of this License, to extend the patent
license to downstream recipients.  "Knowingly relying" means you have
actual knowledge that, but for the patent license, your conveying the
covered work in a country, or your recipient's use of the covered work
in a country, would infringe one or more identifiable patents in that
country that you have reason to believe are valid.

  If, pursuant to or in connection with a single transaction or
arrangement, you convey, or propagate by procuring conveyance of, a
covered work, and grant a patent license to some of the parties
receiving the covered work authorizing them to use, propagate, modify
or convey a specific copy of the covered work, then the patent license
you grant is automatically extended to all recipients of the covered
work and works based on it.

  A patent license is "discriminatory" if it does not include within
the scope of its coverage, prohibits the exercise of, or is
conditioned on the non-exercise of one or more of the rights that are
specifically granted under this License.  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 (a) in connection with copies of the covered work
conveyed by you (or copies made from those copies), or (b) primarily
for and in connection with specific products or compilations that
contain the covered work, unless you entered into that arrangement,
or that patent license was granted, prior to 28 March 2007.

  Nothing in this License shall be construed as excluding or limiting
any implied license or other defenses to infringement that may
otherwise be available to you under applicable patent law.

  12. No Surrender of Others' Freedom.

  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 convey a
covered work so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you may
not convey it at all.  For example, if you agree to terms that obligate you
to collect a royalty for further conveying from those to whom you convey
the Program, the only way you could satisfy both those terms and this
License would be to refrain entirely from conveying the Program.

  13. Remote Network Interaction; Use with the GNU General Public License.

  Notwithstanding any other provision of this License, if you modify the
Program, your modified version must prominently offer all users
interacting with it remotely through a computer network (if your version
supports such interaction) an opportunity to receive the Corresponding
Source of your version by providing access to the Corresponding Source
from a network server at no charge, through some standard or customary
means of facilitating copying of software.  This Corresponding Source
shall include the Corresponding Source for any work covered by version 3
of the GNU General Public License that is incorporated pursuant to the
following paragraph.

  Notwithstanding any other provision of this License, you have
permission to link or combine any covered work with a work licensed
under version 3 of the GNU General Public License into a single
combined work, and to convey the resulting work.  The terms of this
License will continue to apply to the part which is the covered work,
but the work with which it is combined will remain governed by version
3 of the GNU General Public License.

  14. Revised Versions of this License.

  The Free Software Foundation may publish revised and/or new versions of
the GNU Affero 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 the GNU Affero General
Public 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 the
GNU Affero General Public License, you may choose any version ever published
by the Free Software Foundation.

  If the Program specifies that a proxy can decide which future
versions of the GNU Affero General Public License can be used, that proxy's
public statement of acceptance of a version permanently authorizes you
to choose that version for the Program.

  Later license versions may give you additional or different
permissions.  However, no additional obligations are imposed on any
author or copyright holder as a result of your choosing to follow a
later version.

  15. Disclaimer of Warranty.

  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.

  16. Limitation of Liability.

  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
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.

  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
an absolute waiver of all civil liability in connection with the
Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.

                     END OF TERMS AND CONDITIONS

            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
state 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 Affero 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 Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

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

  If your software can interact with users remotely through a computer
network, you should also make sure that it provides a way for users to
get its source.  For example, if your program is a web application, its
interface could display a "Source" link that leads users to an archive
of the code.  There are many ways you could offer source, and different
solutions will be better for different programs; see section 13 for the
specific requirements.

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU AGPL, see
<http://www.gnu.org/licenses/>.

Как применять лицензии GNU со своими программами
Спасибо coh и lorus за то, что о ней вспомнили. Это копилефтная лицензия.

Цитируя Различные лицензии и комментарии к ним:

Ее условия фактически состоят из условий GPLv3 с дополнительным параграфом в разделе 13, который позволяет пользователям, взаимодействующим с лицензируемой программой по сети, получать исходный текст этой программы. Мы рекомендуем разработчикам подумать о применении GNU AGPL для любых программ, которые обычно выполняются в сети.

Есть определенные нюансы совместимости с другими версиями GPL:

Обратите внимание, что GNU AGPL не совместима с GPLv2. Она также формально не совместима с GPLv3 в узком смысле: вы не можете взять исходные тексты, выпущенные на условиях GNU AGPL, и передавать или изменять их, как вам угодно, на условиях GPLv3, и наоборот. Однако вам позволено комбинировать раздельные модули или файлы исходного текста, выпущенные под обеими этими лицензиями, в едином проекте, что предоставит многим программистам разрешение на все действия, нужные им для того, чтобы делать какие им угодно программы.

MPL v2.0 (Mozilla Public License
Version 2.0)

Текст лицензии

Mozilla Public License
Version 2.0
1. Definitions

1.1. “Contributor”

    means each individual or legal entity that creates, contributes to
the creation of, or owns Covered Software.  1.2. “Contributor Version”

    means the combination of the Contributions of others (if any) used
by a Contributor and that particular Contributor’s Contribution.
1.3. “Contribution”

    means Covered Software of a particular Contributor.  1.4. “Covered
Software”

    means Source Code Form to which the initial Contributor has
attached the notice in Exhibit A, the Executable Form of such Source
Code Form, and Modifications of such Source Code Form, in each case
including portions thereof.  1.5. “Incompatible With Secondary
Licenses”

    means

        that the initial Contributor has attached the notice described
        in Exhibit B to the Covered Software; or

        that the Covered Software was made available under the terms
        of version 1.1 or earlier of the License, but not also under
        the terms of a Secondary License.

1.6. “Executable Form”

    means any form of the work other than Source Code Form.
1.7. “Larger Work”

    means a work that combines Covered Software with other material,
in a separate file or files, that is not Covered Software.
1.8. “License”

    means this document.
1.9. “Licensable”

    means having the right to grant, to the maximum extent possible,
whether at the time of the initial grant or subsequently, any and all
of the rights conveyed by this License.  1.10. “Modifications”

    means any of the following:

        any file in Source Code Form that results from an addition to,
        deletion from, or modification of the contents of Covered
        Software; or

        any new file in Source Code Form that contains any Covered Software.

1.11. “Patent Claims” of a Contributor

    means any patent claim(s), including without limitation, method,
process, and apparatus claims, in any patent Licensable by such
Contributor that would be infringed, but for the grant of the License,
by the making, using, selling, offering for sale, having made, import,
or transfer of either its Contributions or its Contributor Version.
1.12. “Secondary License”

    means either the GNU General Public License, Version 2.0, the GNU
Lesser General Public License, Version 2.1, the GNU Affero General
Public License, Version 3.0, or any later versions of those licenses.
1.13. “Source Code Form”

    means the form of the work preferred for making modifications.
1.14. “You” (or “Your”)

    means an individual or a legal entity exercising rights under this
    License. For legal entities, “You” includes any entity that
    controls, is controlled by, or is under common control with
    You. For purposes of this definition, “control” means (a) the
    power, direct or indirect, to cause the direction or management of
    such entity, whether by contract or otherwise, or (b) ownership of
    more than fifty percent (50%) of the outstanding shares or
    beneficial ownership of such entity.

2. License Grants and Conditions
2.1. Grants

Each Contributor hereby grants You a world-wide, royalty-free,
non-exclusive license:

    under intellectual property rights (other than patent or
    trademark) Licensable by such Contributor to use, reproduce, make
    available, modify, display, perform, distribute, and otherwise
    exploit its Contributions, either on an unmodified basis, with
    Modifications, or as part of a Larger Work; and

    under Patent Claims of such Contributor to make, use, sell, offer
    for sale, have made, import, and otherwise transfer either its
    Contributions or its Contributor Version.

2.2. Effective Date

The licenses granted in Section 2.1 with respect to any Contribution
become effective for each Contribution on the date the Contributor
first distributes such Contribution.  2.3. Limitations on Grant Scope

The licenses granted in this Section 2 are the only rights granted
under this License. No additional rights or licenses will be implied
from the distribution or licensing of Covered Software under this
License. Notwithstanding Section 2.1(b) above, no patent license is
granted by a Contributor:

    for any code that a Contributor has removed from Covered Software; or

    for infringements caused by: (i) Your and any other third party’s
    modifications of Covered Software, or (ii) the combination of its
    Contributions with other software (except as part of its
    Contributor Version); or

    under Patent Claims infringed by Covered Software in the absence
    of its Contributions.

This License does not grant any rights in the trademarks, service
marks, or logos of any Contributor (except as may be necessary to
comply with the notice requirements in Section 3.4).  2.4. Subsequent
Licenses

No Contributor makes additional grants as a result of Your choice to
distribute the Covered Software under a subsequent version of this
License (see Section 10.2) or under the terms of a Secondary License
(if permitted under the terms of Section 3.3).  2.5. Representation

Each Contributor represents that the Contributor believes its
Contributions are its original creation(s) or it has sufficient rights
to grant the rights to its Contributions conveyed by this License.
2.6. Fair Use

This License is not intended to limit any rights You have under
applicable copyright doctrines of fair use, fair dealing, or other
equivalents.  2.7. Conditions

Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted
in Section 2.1.  3. Responsibilities 3.1. Distribution of Source Form

All distribution of Covered Software in Source Code Form, including
any Modifications that You create or to which You contribute, must be
under the terms of this License. You must inform recipients that the
Source Code Form of the Covered Software is governed by the terms of
this License, and how they can obtain a copy of this License. You may
not attempt to alter or restrict the recipients’ rights in the Source
Code Form.  3.2. Distribution of Executable Form

If You distribute Covered Software in Executable Form then:

    such Covered Software must also be made available in Source Code
    Form, as described in Section 3.1, and You must inform recipients
    of the Executable Form how they can obtain a copy of such Source
    Code Form by reasonable means in a timely manner, at a charge no
    more than the cost of distribution to the recipient; and

    You may distribute such Executable Form under the terms of this
    License, or sublicense it under different terms, provided that the
    license for the Executable Form does not attempt to limit or alter
    the recipients’ rights in the Source Code Form under this License.

3.3. Distribution of a Larger Work

You may create and distribute a Larger Work under terms of Your
choice, provided that You also comply with the requirements of this
License for the Covered Software. If the Larger Work is a combination
of Covered Software with a work governed by one or more Secondary
Licenses, and the Covered Software is not Incompatible With Secondary
Licenses, this License permits You to additionally distribute such
Covered Software under the terms of such Secondary License(s), so that
the recipient of the Larger Work may, at their option, further
distribute the Covered Software under the terms of either this License
or such Secondary License(s).  3.4. Notices

You may not remove or alter the substance of any license notices
(including copyright notices, patent notices, disclaimers of warranty,
or limitations of liability) contained within the Source Code Form of
the Covered Software, except that You may alter any license notices to
the extent required to remedy known factual inaccuracies.
3.5. Application of Additional Terms

You may choose to offer, and to charge a fee for, warranty, support,
indemnity or liability obligations to one or more recipients of
Covered Software. However, You may do so only on Your own behalf, and
not on behalf of any Contributor. You must make it absolutely clear
that any such warranty, support, indemnity, or liability obligation is
offered by You alone, and You hereby agree to indemnify every
Contributor for any liability incurred by such Contributor as a result
of warranty, support, indemnity or liability terms You offer. You may
include additional disclaimers of warranty and limitations of
liability specific to any jurisdiction.  4. Inability to Comply Due to
Statute or Regulation

If it is impossible for You to comply with any of the terms of this
License with respect to some or all of the Covered Software due to
statute, judicial order, or regulation then You must: (a) comply with
the terms of this License to the maximum extent possible; and (b)
describe the limitations and the code they affect. Such description
must be placed in a text file included with all distributions of the
Covered Software under this License. Except to the extent prohibited
by statute or regulation, such description must be sufficiently
detailed for a recipient of ordinary skill to be able to understand
it.  5. Termination

5.1. The rights granted under this License will terminate
automatically if You fail to comply with any of its terms. However, if
You become compliant, then the rights granted under this License from
a particular Contributor are reinstated (a) provisionally, unless and
until such Contributor explicitly and finally terminates Your grants,
and (b) on an ongoing basis, if such Contributor fails to notify You
of the non-compliance by some reasonable means prior to 60 days after
You have come back into compliance. Moreover, Your grants from a
particular Contributor are reinstated on an ongoing basis if such
Contributor notifies You of the non-compliance by some reasonable
means, this is the first time You have received notice of
non-compliance with this License from such Contributor, and You become
compliant prior to 30 days after Your receipt of the notice.

5.2. If You initiate litigation against any entity by asserting a
patent infringement claim (excluding declaratory judgment actions,
counter-claims, and cross-claims) alleging that a Contributor Version
directly or indirectly infringes any patent, then the rights granted
to You by any and all Contributors for the Covered Software under
Section 2.1 of this License shall terminate.

5.3. In the event of termination under Sections 5.1 or 5.2 above, all
end user license agreements (excluding distributors and resellers)
which have been validly granted by You or Your distributors under this
License prior to termination shall survive termination.  6. Disclaimer
of Warranty

Covered Software is provided under this License on an “as is” basis,
without warranty of any kind, either expressed, implied, or statutory,
including, without limitation, warranties that the Covered Software is
free of defects, merchantable, fit for a particular purpose or
non-infringing. The entire risk as to the quality and performance of
the Covered Software is with You. Should any Covered Software prove
defective in any respect, You (not any Contributor) assume the cost of
any necessary servicing, repair, or correction. This disclaimer of
warranty constitutes an essential part of this License. No use of any
Covered Software is authorized under this License except under this
disclaimer.  7. Limitation of Liability

Under no circumstances and under no legal theory, whether tort
(including negligence), contract, or otherwise, shall any Contributor,
or anyone who distributes Covered Software as permitted above, be
liable to You for any direct, indirect, special, incidental, or
consequential damages of any character including, without limitation,
damages for lost profits, loss of goodwill, work stoppage, computer
failure or malfunction, or any and all other commercial damages or
losses, even if such party shall have been informed of the possibility
of such damages. This limitation of liability shall not apply to
liability for death or personal injury resulting from such party’s
negligence to the extent applicable law prohibits such
limitation. Some jurisdictions do not allow the exclusion or
limitation of incidental or consequential damages, so this exclusion
and limitation may not apply to You.  8. Litigation

Any litigation relating to this License may be brought only in the
courts of a jurisdiction where the defendant maintains its principal
place of business and such litigation shall be governed by laws of
that jurisdiction, without reference to its conflict-of-law
provisions. Nothing in this Section shall prevent a party’s ability to
bring cross-claims or counter-claims.  9. Miscellaneous

This License represents the complete agreement concerning the subject
matter hereof. If any provision of this License is held to be
unenforceable, such provision shall be reformed only to the extent
necessary to make it enforceable. Any law or regulation which provides
that the language of a contract shall be construed against the drafter
shall not be used to construe this License against a Contributor.
10. Versions of the License 10.1. New Versions

Mozilla Foundation is the license steward. Except as provided in
Section 10.3, no one other than the license steward has the right to
modify or publish new versions of this License. Each version will be
given a distinguishing version number.  10.2. Effect of New Versions

You may distribute the Covered Software under the terms of the version
of the License under which You originally received the Covered
Software, or under the terms of any subsequent version published by
the license steward.  10.3. Modified Versions

If you create software not governed by this License, and you want to
create a new license for such software, you may create and use a
modified version of this License if you rename the license and remove
any references to the name of the license steward (except to note that
such modified license differs from this License).  10.4. Distributing
Source Code Form that is Incompatible With Secondary Licenses

If You choose to distribute Source Code Form that is Incompatible With
Secondary Licenses under the terms of this version of the License, the
notice described in Exhibit B of this License must be attached.
Exhibit A - Source Code Form License Notice

    This Source Code Form is subject to the terms of the Mozilla
    Public License, v. 2.0. If a copy of the MPL was not distributed
    with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

If it is not possible or desirable to put the notice in a particular
file, then You may include the notice in a location (such as a LICENSE
file in a relevant directory) where a recipient would be likely to
look for such a notice.

You may add additional accurate notices of copyright ownership.
Exhibit B - “Incompatible With Secondary Licenses” Notice

    This Source Code Form is “Incompatible With Secondary Licenses”,
    as defined by the Mozilla Public License, v. 2.0.

Комментарий от lorus

Для проекта open source стоит ещё рассмотреть MPL 2.0. Своеобразная лицензия, что-то среднее между LGPL и BSD. От LGPL отличается отсутствием заморочек со статическим связыванием. Это может оказаться важным для программ на ЯП, в которых динамическое связывание не предусмотрено.

В случае использования неизмененной библиотеки под MPL 2.0, как части большего проекта, нужно всего лишь указывать, где можно получить исходники этой библиотеки. Но если вы все же меняете код, то обязаны предоставить доступ к измененному вами коду под все той же MPL 2.0. То есть, лицензия копилефтная. Здесь небольшое уточнение от Athari:

Лицензией MPL заражаются файлы, а не проекты, в отличие от (L)GPL. Если изменить файл, он должен остаться под MPL. Если добавить — ограничений нет.

В случае, если проект под GNU GPL, то необходимо сделать используемый в нем код под MPL 2.0 доступным сразу под обеими лицензиями.

Для использования этой лицензии в вашем проекте нужно добавить текст из Exhibit A лицензии

This Source Code Form is subject to the terms of the Mozilla
Public License, v. 2.0. If a copy of the MPL was not distributed
with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

в качестве шапки в каждый файл исходного кода. Лицензия не требует указывать copyright в каждом файле, но и не запрещает этого. Также не забудьте добавить в проект файл LICENSE с текстом лицензии.

EPL-1.0 (Eclipse Public License Version 1.0)

Текст лицензии

Eclipse Public License - v 1.0

THE ACCOMPANYING PROGRAM IS PROVIDED UNDER THE TERMS OF THIS ECLIPSE
PUBLIC LICENSE ("AGREEMENT"). ANY USE, REPRODUCTION OR DISTRIBUTION OF
THE PROGRAM CONSTITUTES RECIPIENT'S ACCEPTANCE OF THIS AGREEMENT.

1. DEFINITIONS

"Contribution" means:

  a) in the case of the initial Contributor, the initial code and
     documentation distributed under this Agreement, and

  b) in the case of each subsequent Contributor:

    i) changes to the Program, and

    ii) additions to the Program;

where such changes and/or additions to the Program originate from and
are distributed by that particular Contributor. A Contribution
'originates' from a Contributor if it was added to the Program by such
Contributor itself or anyone acting on such Contributor's
behalf. Contributions do not include additions to the Program which:
(i) are separate modules of software distributed in conjunction with
the Program under their own license agreement, and (ii) are not
derivative works of the Program.

"Contributor" means any person or entity that distributes the Program.

"Licensed Patents" mean patent claims licensable by a Contributor
which are necessarily infringed by the use or sale of its Contribution
alone or when combined with the Program.

"Program" means the Contributions distributed in accordance with this
Agreement.

"Recipient" means anyone who receives the Program under this
Agreement, including all Contributors.

2. GRANT OF RIGHTS

  a) Subject to the terms of this Agreement, each Contributor hereby
     grants Recipient a non-exclusive, worldwide, royalty-free
     copyright license to reproduce, prepare derivative works of,
     publicly display, publicly perform, distribute and sublicense the
     Contribution of such Contributor, if any, and such derivative
     works, in source code and object code form.

  b) Subject to the terms of this Agreement, each Contributor hereby
     grants Recipient a non-exclusive, worldwide, royalty-free patent
     license under Licensed Patents to make, use, sell, offer to sell,
     import and otherwise transfer the Contribution of such
     Contributor, if any, in source code and object code form. This
     patent license shall apply to the combination of the Contribution
     and the Program if, at the time the Contribution is added by the
     Contributor, such addition of the Contribution causes such
     combination to be covered by the Licensed Patents. The patent
     license shall not apply to any other combinations which include
     the Contribution. No hardware per se is licensed hereunder.

  c) Recipient understands that although each Contributor grants the
     licenses to its Contributions set forth herein, no assurances are
     provided by any Contributor that the Program does not infringe
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По просьбе kidar2 добавляю лицензию EPL. Это копилефтная лицензия, но она не совместима с GNU GPL.

При распространении в форме исходного кода программа должна быть доступна под лицензией EPL.

Автору разрешается распространять программу в форме объектного кода под собственной лицензией, при условии, что: эта лицензия соблюдает условия EPL, явно отказывается от любых гарантий и ответственности от лица всех авторов, указывает, что исходные коды программы доступны у этого автора и объясняет, как их получить.

Применение к своему проекту: копия лицензии должна быть включена во все копии программы

Ms-PL (Microsoft Public License)

Текст лицензии

Microsoft Public License (Ms-PL)

This license governs use of the accompanying software. If you use the
software, you accept this license. If you do not accept the license,
do not use the software.

 1. Definitions

    The terms "reproduce," "reproduction," "derivative works," and
    "distribution" have the same meaning here as under U.S. copyright
    law.

    A "contribution" is the original software, or any additions or
    changes to the software.

    A "contributor" is any person that distributes its contribution
    under this license.

    "Licensed patents" are a contributor's patent claims that read
    directly on its contribution.

 2. Grant of Rights

    (A) Copyright Grant- Subject to the terms of this license,
    including the license conditions and limitations in section 3,
    each contributor grants you a non-exclusive, worldwide,
    royalty-free copyright license to reproduce its contribution,
    prepare derivative works of its contribution, and distribute its
    contribution or any derivative works that you create.
   
    (B) Patent Grant- Subject to the terms of this license, including
    the license conditions and limitations in section 3, each
    contributor grants you a non-exclusive, worldwide, royalty-free
    license under its licensed patents to make, have made, use, sell,
    offer for sale, import, and/or otherwise dispose of its
    contribution in the software or derivative works of the
    contribution in the software.
 
 3. Conditions and Limitations
  
    (A) No Trademark License- This license does not grant you rights
    to use any contributors' name, logo, or trademarks.

    (B) If you bring a patent claim against any contributor over
    patents that you claim are infringed by the software, your patent
    license from such contributor to the software ends automatically.

    (C) If you distribute any portion of the software, you must retain
    all copyright, patent, trademark, and attribution notices that are
    present in the software.

    (D) If you distribute any portion of the software in source code
    form, you may do so only under this license by including a
    complete copy of this license with your distribution. If you
    distribute any portion of the software in compiled or object code
    form, you may only do so under a license that complies with this
    license.  

    (E) The software is licensed "as-is." You bear the risk of using
    it. The contributors give no express warranties, guarantees, or
    conditions. You may have additional consumer rights under your
    local laws which this license cannot change. To the extent
    permitted under your local laws, the contributors exclude the
    implied warranties of merchantability, fitness for a particular
    purpose and non-infringement.

Про лицензию напомнил sensboston. Копилефтная лицензия, несовместимая с GPL. По смыслу схожа с EPL, но написана гораздо, гораздо более человеческм языком. Самая короткая из присутствующих в этой статье копилефтных лицензий.

Обладает даже более слабым копилефтом, чем EPL: если вы распространяете исходные коды проекта, содержащие код под Ms-PL, то все исходные коды проекта должны распространяться под Ms-PL. При этом, распространение в форме объектного кода или бинарной форме позволяется под любой лицензией, не нарушающей Ms-PL. Кроме того, вы обязаны сохранять все копирайты, патенты, торговые марки и указания авторства оригинального кода. Да, лицензия регулирует патентные отношения.

Для применения к своему проекту: скопируйте текст лицензии в ваш проект (например, в файл LICENSE) и распространяйте его вместе с ним.

MIT

Текст лицензии

 Copyright (c) 1998, 1999, 2000 Thai Open Source Software Center Ltd
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
 "Software"), to deal in the Software without restriction, including
 without limitation the rights to use, copy, modify, merge, publish,
 distribute, sublicense, and/or sell copies of the Software, and to
 permit persons to whom the Software is furnished to do so, subject to
 the following conditions:
 
 The above copyright notice and this permission notice shall be included
 in all copies or substantial portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Существует миф, что лицензия MIT существует. Дело в том, что MIT (Massachusetts Institute of Technology) использовал много разных лицензий. Тот текст, который сейчас называют лицензией MIT, в оригинале являлся лицензией Expat, а еще ранее составлял большую часть лицензии X11. Эта лицензия — разрешительная, без копилефта. Она разрешает использование и изменение кода практически любым образом, при условии, что текст самой лицензии и указание авторства никуда не исчезнут, даже если вы разобьете изначальный проект на части. Также неоспоримое достоинство этой лицензии — небольшой размер. В качестве недостатка отмечают отсутствие регулирования патентных отношений. Из-за этого вместо нее GNU рекомендуют использовать другую разрешительную лицензию — Apache 2.0, а MIT предлагают использовать лишь для небольших проектов. Тем не менее, из разрешительных лицензий эта, пожалуй, самая известная.

Для ее применения к своему проекту создайте текстовый файл LICENSE и поместите текст лицензии туда, а также не забудьте заменить данные в строке с копирайтом на верные. Многие дополнительно указывают полный текст лицензии в шапке каждого файла исходного кода.

Apache 2.0

Текст лицензии

                                 Apache License
                           Version 2.0, January 2004
                        http://www.apache.org/licenses/

   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION

   1. Definitions.

      "License" shall mean the terms and conditions for use, reproduction,
      and distribution as defined by Sections 1 through 9 of this document.

      "Licensor" shall mean the copyright owner or entity authorized by
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      "Legal Entity" shall mean the union of the acting entity and all
      other entities that control, are controlled by, or are under common
      control with that entity. For the purposes of this definition,
      "control" means (i) the power, direct or indirect, to cause the
      direction or management of such entity, whether by contract or
      otherwise, or (ii) ownership of fifty percent (50%) or more of the
      outstanding shares, or (iii) beneficial ownership of such entity.

      "You" (or "Your") shall mean an individual or Legal Entity
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      "Source" form shall mean the preferred form for making modifications,
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      "Work" shall mean the work of authorship, whether in Source or
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   2. Grant of Copyright License. Subject to the terms and conditions of
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   3. Grant of Patent License. Subject to the terms and conditions of
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   END OF TERMS AND CONDITIONS

   APPENDIX: How to apply the Apache License to your work.

      To apply the Apache License to your work, attach the following
      boilerplate notice, with the fields enclosed by brackets "[]"
      replaced with your own identifying information. (Don't include
      the brackets!)  The text should be enclosed in the appropriate
      comment syntax for the file format. We also recommend that a
      file or class name and description of purpose be included on the
      same "printed page" as the copyright notice for easier
      identification within third-party archives.

   Copyright [yyyy] [name of copyright owner]

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

Наиболее современная и сбалансированная из разрешительных лицензий. Написана человеческим языком, но с оглядкой на современное правоприменение, в частности, упомянутые выше патентные отношения (пункт 3 лицензии). GNU советуют применять именно эту лицензию, когда вам необходима разрешительная лицензия.

Для применения лицензии Apache 2.0 к вашему проекту, нужно добавить в него файл LICENSE, содержащий текст лицензии. Кроме того, в APPENDIX лицензии нам предлагают добавлять в качестве шапки в каждый файл исходного кода следующий текст:

Copyright [yyyy] [name of copyright owner]

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

Но при этом сама лицензия выдвигает следующие требования:

made available under the License, as indicated by a copyright notice that is included in or attached to the work (an example is provided in the Appendix below)

copyright notice — это как раз строка, указывающая правообладателя. А «made available under the License, as indicated» означает, что еще должна быть явно указана лицензия. То есть, допустимо что-то вида:

Copyright [yyyy] [name of copyright owner]
Licensed under the Apache License, Version 2.0

Причем, совсем необязательно в исходном коде — Apache 2.0 позволяет для этого использовать файл NOTICE («or attached to the work»).

И еще о файле NOTICE: если в вашей работе вы используете чужой проект под лицензией Apache 2.0, содержащий свой файл NOTICE, то в этом случае вы обязаны копировать в производную работу содержимое файла NOTICE, в одно из трех мест: либо в аналогичный файл NOTICE, либо в исходные коды или документацию, распространяемую вместе с производной работой, либо в вывод производной работы (например в about-диалог); все согласно пункту 4 (d) лицензии. Заметьте, что, вопреки расхожему мнению, обязательного наличия файла NOTICE лицензия не требует.

При распространении в бинарной форме, вы, кроме того, должны предоставлять копию лицензии вместе с программой.

BSD

Текст лицензии

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

    (1) Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer. 

    (2) Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in
    the documentation and/or other materials provided with the
    distribution.  
    
    (3)The name of the author may not be used to
    endorse or promote products derived from this software without
    specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.

Это разрешительная лицензия, схожая по смыслу с лицензией MIT. Оригинальная лицензия BSD состояла из 4-х пунктов, но, впоследствии, 3-й пункт, требовавший включать уведомление об авторстве во все рекламные материалы, был исключен. Кроме того, существует и двухпунктовая лицензия BSD, о которой напомнил Athari, в ней удален третий пункт, и эта версия практически совпадает по функциональности с лицензией MIT. GNU советуют вместо лицензии BSD использовать MIT, чтобы исключить путаницу с тем, какая именно версия лицензии BSD используется.

Для ее применения к своему проекту создайте текстовый файл LICENSE и поместите текст лицензии туда. Не забудьте добавить строку с копирайтом. Также, дополнительно можно указать полный текст лицензии в шапке каждого файла исходного кода.

При распространении в бинарной форме лицензия и копирайт должны быть представлены в документации и/или других материалах, распространяемых вместе с бинарником.

WTFPL Version 2

Текст лицензии

            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
                    Version 2, December 2004

 Copyright (C) 2004 Sam Hocevar <[e-mail]>

 Everyone is permitted to copy and distribute verbatim or modified
 copies of this license document, and changing it is allowed as long
 as the name is changed.

            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

  0. You just DO WHAT THE FUCK YOU WANT TO.

Как оказалось, весьма популярная на Хабре лицензия (спасибо Komzpa, Stasik0 и плюсовавшим). Кроме того, она присутствует в списке лицензий GNU, хотя они и постеснялись разместить ее текст на своем сайте.

GNU классифицируют ее как разрешительную некопилефтную лицензию и не рекомендуют ее использовать без каких-либо объяснений. Вместо нее предлагаются MIT или Apache 2.0.

Могу предположить причины:

• во-первых, лицензия содержит лексику, которая может считаться ненормативной (и я не уверен, что в таком случае лицензию будут принимать в расчет, скажем, в суде),
• во-вторых, в лицензии никак не прописан отказ от ответственности,
• в-третьих, у меня есть подозрение, что разрешение пользователю делать с кодом все что угодно тоже может быть оспорено юристами.

Чтобы применить ее к своему проекту — просто добавьте файл с лицензией в проект и не забудьте поменять в лицензии строку с копирайтом. Можно также добавить лицензию в шапку ко всем исходникам проекта.

Beerware

Текст лицензии

/*
* — * «THE BEER-WARE LICENSE» (Revision 42):
* <[e-mail]> wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* — */

Еще одна лицензия, набравшая плюсов в комменатриях (спасибо JDima и плюсовавшим). Это тоже разрешительная лицензия, которая пытается разрешить все (ключевое слово «пытается») и содержит необязательное условие поставить автору пива (в других версиях, выпить в честь автора) при встрече, если вам понравился его проект.

Как известно, «чрезмерное употребление пива вредит вашему здоровью». Но беда этой лицензии не в пиве. Обратите внимание на фразу

<[e-mail]> wrote this file. As long as you retain this notice...

Теперь представьте, что вы изменили код этого файла. Или вы взяли код из этого файла, чтобы добавить в свой. Теперь фраза

<[e-mail]> wrote this file.

является неверной, но вы обязаны ее сохранить! То есть, лицензия пытается отобрать у вас право указывать авторство произведения. А, например, в России автор имеет неимущественные и неотчуждаемые право авторства и право автора на имя. Получается, что такая лицензия, разрешая изменения и использование кода и запрещая указывать новых авторов, является незаконной (по-хорошему, нужно уточнить у юриста).

Общественное достояние (Public Domain)

Это, конечно же, не лицензия. Но многие рассматривают перевод произведения в общественное достояние как способ сложить с себя имущественные права. Периодически люди пытаются сделать это и в отношении программ. Обычно просто пишут, что проект находится в Public Domain и радуются, что все смогут им пользоваться. Но на самом деле это не так! В разных странах общественное достояние разное. Причем, в большинстве из них закон явно не предусматривает механизмов для перевода произведения в общественное достояние по желанию автора! Например, в России переход в общественное достояние определен только по истечению срока действия защиты авторского права. В США, насколько мне известно, досрочной процедуры тоже не предусмотрено. Кроме того, могут быть сложности и с использованием произведений, находящихся в общественном достоянии. Скажем, в Уругвае, для того, чтобы использовать произведение из общественного достояния, вам понадобится уплатить пошлину государству и получить разрешение специальной комиссии, которая удостоверится, что вы не будете использовать данное произведение как-то непотребно (правда, я не знаю, работает ли все это в отношении программ). Вследствие подобных нюансов, появились лицензии подобные следующей.

CC0 (Creative Commons CC0)

Текст лицензии

     CREATIVE COMMONS CORPORATION IS NOT A LAW FIRM AND DOES NOT
     PROVIDE LEGAL SERVICES. DISTRIBUTION OF THIS DOCUMENT DOES NOT
     CREATE AN ATTORNEY-CLIENT RELATIONSHIP. CREATIVE COMMONS PROVIDES
     THIS INFORMATION ON AN "AS-IS" BASIS. CREATIVE COMMONS MAKES NO
     WARRANTIES REGARDING THE USE OF THIS DOCUMENT OR THE INFORMATION
     OR WORKS PROVIDED HEREUNDER, AND DISCLAIMS LIABILITY FOR DAMAGES
     RESULTING FROM THE USE OF THIS DOCUMENT OR THE INFORMATION OR
     WORKS PROVIDED HEREUNDER.

Statement of Purpose

The laws of most jurisdictions throughout the world automatically
confer exclusive Copyright and Related Rights (defined below) upon the
creator and subsequent owner(s) (each and all, an "owner") of an
original work of authorship and/or a database (each, a "Work").

Certain owners wish to permanently relinquish those rights to a Work
for the purpose of contributing to a commons of creative, cultural and
scientific works ("Commons") that the public can reliably and without
fear of later claims of infringement build upon, modify, incorporate
in other works, reuse and redistribute as freely as possible in any
form whatsoever and for any purposes, including without limitation
commercial purposes. These owners may contribute to the Commons to
promote the ideal of a free culture and the further production of
creative, cultural and scientific works, or to gain reputation or
greater distribution for their Work in part through the use and
efforts of others.

For these and/or other purposes and motivations, and without any
expectation of additional consideration or compensation, the person
associating CC0 with a Work (the "Affirmer"), to the extent that he or
she is an owner of Copyright and Related Rights in the Work,
voluntarily elects to apply CC0 to the Work and publicly distribute
the Work under its terms, with knowledge of his or her Copyright and
Related Rights in the Work and the meaning and intended legal effect
of CC0 on those rights.

1. Copyright and Related Rights. A Work made available under CC0 may
be protected by copyright and related or neighboring rights
("Copyright and Related Rights"). Copyright and Related Rights
include, but are not limited to, the following:

    the right to reproduce, adapt, distribute, perform, display,
    communicate, and translate a Work; moral rights retained by the
    original author(s) and/or performer(s); publicity and privacy
    rights pertaining to a person's image or likeness depicted in a
    Work; rights protecting against unfair competition in regards to a
    Work, subject to the limitations in paragraph 4(a), below; rights
    protecting the extraction, dissemination, use and reuse of data in
    a Work; database rights (such as those arising under Directive
    96/9/EC of the European Parliament and of the Council of 11 March
    1996 on the legal protection of databases, and under any national
    implementation thereof, including any amended or successor version
    of such directive); and other similar, equivalent or corresponding
    rights throughout the world based on applicable law or treaty, and
    any national implementations thereof.

2. Waiver. To the greatest extent permitted by, but not in
contravention of, applicable law, Affirmer hereby overtly, fully,
permanently, irrevocably and unconditionally waives, abandons, and
surrenders all of Affirmer's Copyright and Related Rights and
associated claims and causes of action, whether now known or unknown
(including existing as well as future claims and causes of action), in
the Work (i) in all territories worldwide, (ii) for the maximum
duration provided by applicable law or treaty (including future time
extensions), (iii) in any current or future medium and for any number
of copies, and (iv) for any purpose whatsoever, including without
limitation commercial, advertising or promotional purposes (the
"Waiver"). Affirmer makes the Waiver for the benefit of each member of
the public at large and to the detriment of Affirmer's heirs and
successors, fully intending that such Waiver shall not be subject to
revocation, rescission, cancellation, termination, or any other legal
or equitable action to disrupt the quiet enjoyment of the Work by the
public as contemplated by Affirmer's express Statement of Purpose.

3. Public License Fallback. Should any part of the Waiver for any
reason be judged legally invalid or ineffective under applicable law,
then the Waiver shall be preserved to the maximum extent permitted
taking into account Affirmer's express Statement of Purpose. In
addition, to the extent the Waiver is so judged Affirmer hereby grants
to each affected person a royalty-free, non transferable, non
sublicensable, non exclusive, irrevocable and unconditional license to
exercise Affirmer's Copyright and Related Rights in the Work (i) in
all territories worldwide, (ii) for the maximum duration provided by
applicable law or treaty (including future time extensions), (iii) in
any current or future medium and for any number of copies, and (iv)
for any purpose whatsoever, including without limitation commercial,
advertising or promotional purposes (the "License"). The License shall
be deemed effective as of the date CC0 was applied by Affirmer to the
Work. Should any part of the License for any reason be judged legally
invalid or ineffective under applicable law, such partial invalidity
or ineffectiveness shall not invalidate the remainder of the License,
and in such case Affirmer hereby affirms that he or she will not (i)
exercise any of his or her remaining Copyright and Related Rights in
the Work or (ii) assert any associated claims and causes of action
with respect to the Work, in either case contrary to Affirmer's
express Statement of Purpose.

4. Limitations and Disclaimers.

    No trademark or patent rights held by Affirmer are waived,
    abandoned, surrendered, licensed or otherwise affected by this
    document.  Affirmer offers the Work as-is and makes no
    representations or warranties of any kind concerning the Work,
    express, implied, statutory or otherwise, including without
    limitation warranties of title, merchantability, fitness for a
    particular purpose, non infringement, or the absence of latent or
    other defects, accuracy, or the present or absence of errors,
    whether or not discoverable, all to the greatest extent
    permissible under applicable law.  Affirmer disclaims
    responsibility for clearing rights of other persons that may apply
    to the Work or any use thereof, including without limitation any
    person's Copyright and Related Rights in the Work. Further,
    Affirmer disclaims responsibility for obtaining any necessary
    consents, permissions or other rights required for any use of the
    Work.  Affirmer understands and acknowledges that Creative Commons
    is not a party to this document and has no duty or obligation with
    respect to this CC0 or use of the Work.

Creative Commons CC0 — лицензия, которая пытается перевести проект в общественное достояние в максимальной форме, разрешенной законом. А если закон не позволяет это совершить, автоматически применяет положения разрешительной лицензии. GNU рекомендует применять CC0 в том случае, если вы хотите перевести вашу работу в общественное достояние.

Про применение CC0 к проекту можно прочитать в этой статье.

Unlicense

Текст лицензии

This is free and unencumbered software released into the public domain.

Anyone is free to copy, modify, publish, use, compile, sell, or
distribute this software, either in source code form or as a compiled
binary, for any purpose, commercial or non-commercial, and by any
means.

In jurisdictions that recognize copyright laws, the author or authors
of this software dedicate any and all copyright interest in the
software to the public domain. We make this dedication for the benefit
of the public at large and to the detriment of our heirs and
successors. We intend this dedication to be an overt act of
relinquishment in perpetuity of all present and future rights to this
software under copyright law.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

For more information, please refer to <http://unlicense.org/>

Про лицензию напомнил Athari. Эта лицензия появилась путем копипасты текста о передаче в общественное достояние и отказа от прав (waiver) проекта SQLite и отказа от гарантий из лицензии MIT. Аналогично лицензии CC0, Unlicense пытается перевести работу в общественное достояние и послужить в виде лицензионного договора на случай, если этого не произошло. Однако, эта лицензия менее проработана, чем CC0, из-за чего может являться нелегальной. Вот в этом вопросе на stackexchange подробнее. Вкратце, там указано, что лицензия явно нелегальна, например, в Германии, так как там, похоже, нет понятия общественного достояния. А Unlicense, в отличие от CC0, не отказывается от перевода в общественное достояние для случая, когда это противоречит закону. Кроме того лицензия как минимум нелогична (или даже противоречива), так как передача в общественное достояние, заявленная в первой строке, в случае успеха делает невалидными параграфы, следующие за ней.

Для применения Unlicense нужно добавить файл с текстом лицензии к вашему проекту. Авторы лицензии рекомендуют назвать файл UNLICENSE.

Copyright в исходниках

Наверное, вы заметили, что многие лицензии предлагают размещать определенный текст в виде комментария в шапке файла? Если это является обязательным требованием, то тогда ему нужно следовать. Но насколько необходим подобный текст, если явного требования лицензия не предъявляет?

Хорошие новости: в таком случае лицензию и даже копирайт совершенно не обязательно указывать в шапке файла. Ваша работа и так ваша, для подтверждения этого указывать копирайт нет необходимости. Подтверждать авторство или обладание правами вам все равно придется другими способами, а текст лицензии может находиться в отдельном файле.

Но все же такой заголовок лучше иметь. Основные причины следующие:

• Он четко показывает, что права на код кому-то принадлежат. Отмазки вида «я не знал, там не написано, не смог найти, не заметил» уже не прокатят. Иначе говоря, наличие такого заголовка предотвращает случайное неправомерное использование кода, а также может увеличить ответственность за намеренное.
• Дает возможность идентифицировать владельца прав на код, чтобы связаться с ним в том числе и по вопросам правомерности использования этого кода.

Между прочим, это имеет смысл не только для open-source проекта. Указание владельца прав и авторства может помочь и проприетарному коду в том случае, если он каким-либо образом утечет в сеть.

Если вы решили, что уведомление о правах на файл исходного кода вам необходимо, то вот что оно должно содержать в идеале:

• Copyright — так как в некоторых странах одного символа копирайта недостаточно для юридической значимости уведомления.
• © — символ копирайта, в большинстве стран он необходим и достаточен для придания юридической значимости уведомлению. Простой буквы c в скобках ( c ) для этого может быть недостаточно. Используйте уже Unicode!
• 2007, 2009, 2010 – 2012 — «годы жизни» кода, первое число — год, когда продукт был впервые опубликован, далее — годы, когда код обновлялся. Если годы, когда код в файле правился, идут не подряд, то их нужно указывать через запятую.
• John Doe — имя владельца авторских прав. Не автора, это могут быть разные лица! Может быть именем человека, названием компании, или именами нескольких человек. Правда, в последнем случае лучше сделать отдельную строчку на каждого человека.
• All rights reserved — «все права защищены», означает, что указанные лица обладают всеми правами на код. Дополнительное усиление уведомления копирайта, в случае обладания исключительными правами.
• Если возможно, то дать ссылку на лицензионный договор или указание, где его искать.
• Указать контактные данные.

Обратите внимание, что имя автора в уведомление не входит. Автора/авторов можно указать отдельно, например, на следующей строке, в свободной форме (например Author: Jane Doe).

Ну и, на всякий случай, примеры

// Copyright © 2022 John Doe. All rights reserved.

// Copyright © 2022-2096 Acme Corporation. All rights reserved.
// Author: John Doe

// Copyright © 2022 John Doe
// Copyright © 2023-2028 Jane Doe
// Copyright © 2028-2096 Acme Corporation. Contacts: <[e-mail]>
// License: http://opensource.org/licenses/MIT

Заключение

Разместить ваш проект в интернете и написать «пользуйтесь все!» еще недостаточно для того, чтобы им действительно начали пользоваться. И речь не о рекламе или полезности конкретного проекта. Часто необходимо четкое понимание, как можно и как нельзя использовать проект, особенно, если цели использования — коммерческие. В том числе, слова «пользуйтесь все» вряд ли удастся представить договором с правообладателем в случае каких-либо проблем.

При выборе лицензии задумайтесь, в первую очередь, о том, что лицензию вы пишете в большей степени не для себя, а для тех, кто вашим кодом будет пользоваться. Она регулирует ваши отношения с ними. Кто будет использовать ваш код? Как они будут его использовать? Какая из лицензий будет им удобнее? Какие проблемы из-за лицензии могут возникнуть у них? А у вас? Ответив на подобные вопросы, можно подобрать наилучшую лицензию.

В свою очередь, если вы используете чужой проект в своих целях, то нужно понять ограничения, накладываемые на вас его лицензией. Подходят ли они вам, сможете ли вы выполнить эти требования?

Лицензия, даже свободная, является договором между правообладателем и пользователем. Старайтесь рассматривать это именно так.

Материалы

1. Право интеллектуальной собственности. Шпаргалка, Коллектив авторов
2. Служебное произведение, Википедия
3. Moral rights, Wikipedia
4. Лицензия на программное обеспечение, Википедия
5. Определение свободного программного обеспечения, Википедия
6. Критерии Debian по определению свободного программного обеспечения, Википедия
7. Свободная лицензия, Википедия
8. Проприетарное программное обеспечение, Википедия
9. Ричард Столлман, Википедия
10. Брюс Перенс, Википедия
11. Открытое программное обеспечение, Википедия
12. Разрешительная лицензия свободного ПО, Википедия
13. Various licenses and comments about them/Различные лицензии и комментарии к ним, GNU
14. Копилефт, Википедия
15. Understanding Open Source and Free Software Licensing, Andrew M. St. Laurent
16. GNU Lesser General Public License, Википедия
17. Почему вам не следует применять Меньшую GPL для своей следующей библиотеки, GNU
18. Frequently Asked Questions about the GNU Licenses, GNU
19. Как применять лицензии GNU со своими программами, GNU
20. Лицензия BSD, Википедия
21. Общественное достояние, Википедия
22. Ley 9.739, Propiedad literaria y artistica, leyes de la República Oriental del Uruguay
23. Uruguay: Dominio Público pero Pagante, Fundación Karisma con Open Business Latinamerica and the Caribbean
24. Managing copyright information within a free software project, Software Freedom Law Center
25. Using copyright notices, The UK Copyright Service
26. Get rid of source code templates, Ville Laurikari
27. MPL 2.0 FAQ, Mozilla Foundation
28. «The Beerware License» Considered Harmful, RM
29. How does MS-PL license work? Stackoverflow
30. Unlicense Yourself: Set Your Code Free
31. What is wrong with the Unlicense?

Update
Добавил GNU GPL Version 2, спасибо, wholeman
Добавил MPL Version 2.0, спасибо, lorus
Поправлено описание GNU GPL, спасибо, coh
Поправлено описание Apache 2.0, благодаря eyeofhell
Добавил WTFPL Version 2, спасибо Komzpa, Stasik0 и плюсовавшим
Добавил Beerware license, спасибо JDima и плюсовавшим
Добавил GNU AGPL, спасибо coh, lorus
Добавил EPL Version 1.0, спасибо, kidar2
Добавил Ms-PL и ссылку на еще один список лицензий, спасибо, sensboston
Добавил в описание GPLv2 и GPLv3 ссылку на «Практическое руководство по соответствию GPL», спасибо, Indexator
Добавил ссылку на сайт LicenseIT, спасибо, sensboston
Добавил в описание GPLv3 еще одну ссылку, еше раз спасибо, Indexator
Добавил описание Unlicense и внес правки в описания LGPL, MPL, MIT, BSD, спасибо, Athari