GNU General Public License

The license was originally written by Richard Stallman, former head of the Free Software Foundation (FSF), for the GNU Project, and grants the recipients of a computer program the rights of the Free Software Definition.

Stallman launched the GNU Project, founded the Free Software Foundation, developed the GNU Compiler Collection and GNU Emacs, and wrote the GNU General Public License.

The license was originally written by Richard Stallman, former head of the Free Software Foundation (FSF), for the GNU Project, and grants the recipients of a computer program the rights of the Free Software Definition.

The Free Software Foundation (FSF) is a 501(c)(3) non-profit organization founded by Richard Stallman on 4 October 1985 to support the free software movement, which promotes the universal freedom to study, distribute, create, and modify computer software, with the organization's preference for software being distributed under copyleft ("share alike") terms, such as with its own GNU General Public License.

Prominent free-software programs licensed under the GPL include the Linux kernel and the GNU Compiler Collection (GCC). The original GPL was based on a unification of similar licenses used for early versions of GNU Emacs (1985), the GNU Debugger, and the GNU C Compiler. The first known violation of the GPL was in 1989, when NeXT extended the GCC compiler to support Objective-C, but did not publicly release the changes.

The Free Software Foundation (FSF) distributes GCC under the GNU General Public License (GNU GPL).

The original GPL was based on a unification of similar licenses used for early versions of GNU Emacs (1985), the GNU Debugger, and the GNU C Compiler.

The terms of the GNU General Public License (GPL) state that the Emacs source code, including both the C and Emacs Lisp components, are freely available for examination, modification, and redistribution.

These problems included tivoization (the inclusion of GPL-licensed software in hardware that refuses to run modified versions of its software), compatibility issues similar to those of the Affero General Public License—and patent deals between Microsoft and distributors of free and open-source software, which some viewed as an attempt to use patents as a weapon against the free software community.

The first version of the Affero General Public License (AGPLv1), was published by Affero, Inc. in March 2002, and based on the GNU General Public License, version 2 (GPLv2).

The original GPL was based on a unification of similar licenses used for early versions of GNU Emacs (1985), the GNU Debugger, and the GNU C Compiler.

GDB is free software released under the GNU General Public License (GPL).

These problems included tivoization (the inclusion of GPL-licensed software in hardware that refuses to run modified versions of its software), compatibility issues similar to those of the Affero General Public License—and patent deals between Microsoft and distributors of free and open-source software, which some viewed as an attempt to use patents as a weapon against the free software community. According to Stallman, the most important changes were in relation to software patents, free software license compatibility, the definition of "source code", and hardware restrictions on software modification ("tivoization").

Tivoization is the creation of a system that incorporates software under the terms of a copyleft software license (like the GPL), but uses hardware restrictions to prevent users from running modified versions of the software on that hardware.

While the "GPLv2 or any later version" clause is considered by FSF as the most common form of licensing GPLv2 software, Toybox developer Rob Landley described it as a lifeboat clause.

Toybox aims to provide a BSD licensed replacement for the GPL licensed BusyBox.

GPLv3 was written by Richard Stallman, with legal counsel from Eben Moglen and Richard Fontana from the Software Freedom Law Center. In late 2007, the BusyBox developers and the Software Freedom Law Center embarked upon a program to gain GPL compliance from distributors of BusyBox in embedded systems, suing those who would not comply.

SFLC represented and advised the Free Software Foundation, one of its principal clients, throughout the process of drafting and public discussion of version 3 of the GNU General Public License (GPLv3) during 2005–2007.

Software under the GPL may be run for all purposes, including commercial purposes and even as a tool for creating proprietary software, such as when using GPL-licensed compilers.

However, software running as an application program under a GPL-licensed operating system such as Linux is not required to be licensed under GPL or to be distributed with source-code availability—the licensing depends only on the used libraries and software components and not on the underlying platform.

The source code may be used, modified and distributed—commercially or non-commercially—by anyone under the terms of its respective licenses, such as the GNU General Public License.

Comments were collected from the public via the gplv3.fsf.org web portal, using purpose-written software called stet.

The software was built to facilitate public consultation during the Version 3 draft process of the GNU General Public License.

GPLv3 was written by Richard Stallman, with legal counsel from Eben Moglen and Richard Fontana from the Software Freedom Law Center.

In 2012 Fontana began drafting copyleft-next, a modification of the GNU General Public License, version 3 (GPLv3).

According to Stallman, the most important changes were in relation to software patents, free software license compatibility, the definition of "source code", and hardware restrictions on software modification ("tivoization").

Version 2 of the GNU General Public License does not allow software to be distributed if that software requires a patent licence that does not "permit royalty-free redistribution of the Program by all those who receive copies directly or indirectly through you".

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

It is similar to the GNU General Public License, giving readers the rights to copy, redistribute, and modify (except for "invariant sections") a work and requires all copies and derivatives to be available under the same license.

This is discouraged, however, since such a license might be incompatible with the GPL and causes a perceived license proliferation.

Therefore, some consider compatibility with the widely used GNU General Public License (GPL) an important characteristic, for instance David A. Wheeler as also the Free Software Foundation (FSF), who maintains a list of the licenses that are compatible with the GPL.

The GPL is a copyleft license, which means that derivative work must be open-source and distributed under the same license terms.

The GNU General Public License (GPL), originally written by Richard Stallman, was the first software copyleft license to see extensive use, and continues to dominate in that area.

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

The GNU Affero General Public License is a free, copyleft license published by the Free Software Foundation in November 2007, and based on the GNU General Public License, version 3 and the Affero General Public License.

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

Drupal is a free and open-source content management framework written in PHP and distributed under the GNU General Public License.

Others, notably some high-profile Linux kernel developers such as Linus Torvalds, Greg Kroah-Hartman, and Andrew Morton, commented to the mass media and made public statements about their objections to parts of discussion drafts 1 and 2.

Torvalds used Stallman's GNU General Public License version 2 (GPLv2) for his Linux kernel.

Other licenses created by the GNU project include the GNU Lesser General Public License, GNU Free Documentation License, and Affero General Public License. The version numbers diverged in 1999 when version 2.1 of the LGPL was released, which renamed it the GNU Lesser General Public License to reflect its place in the philosophy.

The LGPL was developed as a compromise between the strong copyleft of the GNU General Public License (GPL) and more permissive licenses such as the BSD licenses and the MIT License.

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

The software is released under the GPLv2 (or later) license.

In late 2007, the BusyBox developers and the Software Freedom Law Center embarked upon a program to gain GPL compliance from distributors of BusyBox in embedded systems, suing those who would not comply.

It is released as free software under the terms of the GNU General Public License, version 2.

The license was originally written by Richard Stallman, former head of the Free Software Foundation (FSF), for the GNU Project, and grants the recipients of a computer program the rights of the Free Software Definition.

In 1991, the Linux kernel appeared, developed outside the GNU project by Linus Torvalds, and in December 1992 it was made available under version 2 of the GNU General Public License.

The first known violation of the GPL was in 1989, when NeXT extended the GCC compiler to support Objective-C, but did not publicly release the changes.

In order to circumvent the terms of the GPL, NeXT had originally intended to ship the Objective-C frontend separately, allowing the user to link it with GCC to produce the compiler executable.