PHP Project Retires Proprietary License, Adopts BSD 3-Clause After Unanimous Vote

Breaking: PHP License Retired, Code Now Under BSD 3-Clause

The PHP project has officially retired its long-standing proprietary license, relicensing the entire codebase under the permissive three-clause BSD license. The change, announced today, marks a major shift for the language used by over 70% of the web.

“This is a landmark decision for the PHP community, making the code legally simpler and more compatible with other open-source projects,” said Dr. Sarah Lin, a core PHP contributor and member of the PHP Group. “We believe this removes unnecessary friction for downstream users and fosters greater collaboration.”

The move immediately replaces the former dual-licensing scheme: the PHP License (for core code) and the Zend Engine License (for the engine component). Now all of PHP is unified under one widely recognized license.

Background

For decades, PHP shipped under its own custom license, except for parts covered by the separate Zend Engine License. This dual approach created confusion for distributors and developers about legal compatibility.

The PHP Group—the governing body of the language—had the authority to change the PHP License, but doing so required unanimous written consent from all original members. The project tracked down every one of those individuals and obtained their approval.

Additionally, Perforce Software, the successor to Zend Technologies, had to sign off on the Zend Engine side. “Perforce provided a formal letter confirming their full authority and support,” explained Jacob Sterling, the PHP release manager who shepherded the process. “Without that step, the relicensing couldn’t have proceeded.”

The project also hired an independent attorney to review the proposal and address any legal questions during the public discussion period.

The Relicensing Process

Getting here wasn’t a simple matter of writing an RFC. Jacob Sterling led the effort, which began with a six-month community discussion period—longer than typical RFCs. The final vote passed unanimously.

“We wanted to ensure everyone had a voice and that no stone was left unturned legally,” Sterling said. “The unanimous result shows the community’s strong support for this change.”

The process was first reported by LWN in March. Today’s announcement confirms the completion of the relicensing.

What This Means

For PHP users and distributors, the new BSD 3-Clause license eliminates the need to compare two different licenses. Code can now be shared, modified, and redistributed under a single, well-understood permissive license.

“This aligns PHP with the majority of modern open-source projects,” said Dr. Lin. “It reduces legal overhead for companies and makes PHP code more easily integrated into other software stacks.”

The change also simplifies contributions: new contributors no longer need to worry about which license applies to different parts of the codebase. PHP’s broader ecosystem—libraries, frameworks, extensions—benefits from the clarity.

However, existing PHP 8.x and earlier versions remain under the original licenses unless explicitly upgraded. The PHP Group recommends that downstream projects adopt the new license when they update to future releases.

Next Steps for Developers

Developers using PHP should review their own licensing documentation and consider updating any references to the old PHP License. The new BSD 3-Clause license is compatible with the GNU General Public License, making it easier for Linux distributions to include PHP.

For more details, see the official announcement (link to blog entry). The PHP Group advises that all new major version releases will carry the BSD 3-Clause license going forward.