The ''PHP License'' is the
open-source license
Open-source licenses are software licenses that allow content to be used, modified, and shared. They facilitate free and open-source software (FOSS) development. Intellectual property (IP) laws restrict the modification and sharing of creative ...
under which the
PHP scripting language is released. The PHP License is designed to encourage widespread adoption of the source code. Redistribution is permitted in
source or
binary form with or without modifications, with some caveats.
Version 3 of PHP used a
dual license—PHP 3's source is available under either the PHP License or the
GNU General Public License
The GNU General Public Licenses (GNU GPL or simply GPL) are a series of widely used free software licenses, or ''copyleft'' licenses, that guarantee end users the freedom to run, study, share, or modify the software. The GPL was the first ...
(GPL). This practice was discontinued as of PHP 4, with PHP's developers citing the restrictions on reuse associated with the GPL's
copyleft
Copyleft is the legal technique of granting certain freedoms over copies of copyrighted works with the requirement that the same rights be preserved in derivative works. In this sense, ''freedoms'' refers to the use of the work for any purpose, ...
enforcement as being the reason for dropping it. The
Zend Engine, the core of the PHP interpreter, is separately licensed under the similar Zend Engine License, which contains similar naming restrictions to the PHP license (applying to the names "Zend" and "Zend Engine"), and a clause requiring advertising materials to mention its use.
Criticism
The PHP License is an
open source license according to the
Open Source Initiative
The Open Source Initiative (OSI) is a California public benefit corporation "actively involved in Open Source community-building, education, and public advocacy to promote awareness and the importance of non-proprietary software".
Governance
The ...
, and a non-
copyleft
Copyleft is the legal technique of granting certain freedoms over copies of copyrighted works with the requirement that the same rights be preserved in derivative works. In this sense, ''freedoms'' refers to the use of the work for any purpose, ...
free software
Free software, libre software, libreware sometimes known as freedom-respecting software is computer software distributed open-source license, under terms that allow users to run the software for any purpose as well as to study, change, distribut ...
license according to the
Free Software Foundation
The Free Software Foundation (FSF) is a 501(c)(3) non-profit organization founded by Richard Stallman on October 4, 1985. The organisation supports the free software movement, with the organization's preference for software being distributed ...
.
The license is
GPL-incompatible due to restrictions on the usage of the term ''PHP''.
Debian
Debian () is a free and open-source software, free and open source Linux distribution, developed by the Debian Project, which was established by Ian Murdock in August 1993. Debian is one of the oldest operating systems based on the Linux kerne ...
maintainers have had a long-standing discussion (since at least 2005) about the validity of the PHP license. Expressed concerns include that the license "contains statements about the software it covers that are specific to distributing PHP itself", which, for other software than PHP itself therefore would be "false statements".
Debian has a specific policy for the license (and requires a statement in debian/copyright file when it is used): "The PHP license must only be used for PHP and PHP add-ons."
See also
*
Apache License
The Apache License is a permissive free software license written by the Apache Software Foundation (ASF). It allows users to use the software for any purpose, to distribute it, to modify it, and to distribute modified versions of the software ...
*
Software using the PHP license (category)
References
External links
Official PHP License InformationZend Grant Documents
{{DEFAULTSORT:Php License
Free and open-source software licenses
PHP