The developers of the PHP programming language have notified the OSI (Open Source Initiative) about the voluntary withdrawal of the PHP License 3.01. It has been stated that after several years of work, the PHP toolkit code has been fully transitioned to the BSD-3 license, and there is no longer any code remaining under the old PHP License 3.01. The text of the new PHP License version has been replaced with a copy of the BSD-3 license.
Previously, the PHP interpreter and Zend Engine were distributed under different licenses, the PHP License and the Zend Engine License. Transitioning to a unified BSD-3 license will simplify licensing terms, ensure compatibility with GPL, and resolve long-standing issues while preserving all rights for users and developers. The previously used licenses were deemed incompatible with the GPL by the Open Source Foundation due to a clause preventing the use of the word PHP in promoting derivative products without written permission.
Initially, the PHP 1.x and 2.x branches were supplied under the GPLv2 license, but the PHP 3 branch transitioned to a dual license model — PHP License and GPL. In PHP 4, the license was changed again — the main code was distributed solely under the PHP License, while the Zend Engine, which serves as the core interpreter for PHP, was placed in a 'Zend/' subdirectory under a separate Zend Engine License. The Zend Engine License, like the PHP License, contains restrictions regarding the use of the term Zend in derivative products, but additionally requires acknowledgment of the engine's use in promotional materials.
After the transition to the BSD-3 license, the copyrights of all participants in the development have been preserved, and users' rights remain unchanged. The new license imposes no additional restrictions and does not infringe on existing rights regarding the use, modification, and distribution of the product. The PHP and Zend licenses are based on the text of the 4-clause BSD license, and the shift to the BSD-3 license only resulted in the removal of clauses defining requirements concerning the use of the 'PHP' brand, as well as the elimination of the provision mandating disclosure of the use of the PHP open-source project in derivative products.
The change of license did not require obtaining separate consent from each developer, as the texts of the PHP and Zend licenses define the powers allowing the PHP Group to make changes to the license and issue new versions of the license. Approval from the PHP Group members and written confirmation from the lawyers of Perforce Software, which owns Zend Technologies, was sufficient for the transition to the BSD-3 license. The process of transitioning to the new license is formalized as an update to the PHP License v4 and Zend Engine License v3, the texts of which align with the BSD-3 license text.
Source: opennet.ru
