License Information
You can download the text of the latest version (3.0) of the PHP license here.
Frequently Asked Questions
Q. I've written a project in PHP that I'm going to release as open source, and I'd like to call it PHPTransmogrifier. Is that OK?
A. We cannot really stop you from using PHP in the name of your project unless you include any code from the PHP distribution, in which case you would be violating the license. But we would really prefer if people would come up with their own names independent of the PHP name.
Why you ask? You are only trying to contribute to the PHP community. That may be true, but by using the PHP name you are explicitly linking your efforts to those of the entire PHP development community and the years of work that has gone into the PHP project. Every time a flaw is found in one of the thousands of applications out there that call themselves "PHP-Something" the negative karma that generates reflects unfairly on the entire PHP project. We had nothing to do with PHP-Nuke, for example, and every bugtraq posting on that says "PHP" in it. Your particular project may in fact be the greatest thing ever, but we have to be consistent in how we handle these requests and we honestly have no way of knowing whether your project is actually the greatest thing ever.
So, please, pick a name that stands on its own merits. If your stuff is good, it will not take long to establish a reputation for yourselves. Look at Zope, for example, that is a framework for Python that doesn't have Python in the name. Smarty as well doesn't have PHP in the name and does quite well.
Q. Why is PHP 4 not dual-licensed under the GNU General Public License (GPL) like PHP 3 was?
A. GPL enforces many restrictions on what can and cannot be done with the licensed code. The PHP developers decided to release PHP under a much more loose license (Apache-style), to help PHP become as popular as possible.
Note: the following questions and answers only apply to version 2.01 and 2.02 of the PHP license. Ignore for version 3.0.
Q. What does the PHP license mean then, in simple words?
A. (Note: This answer should in no way be taken to replace the PHP license, it is intended to give you a general impression of what the license means.) Essentially, the PHP license gives you the right to use, distribute and modify PHP as much as you want, for both commercial and non-commercial use. You just have to make it clear to the user that what you have distributed contains PHP.
Q. The Zend license says I may not charge money for stuff I sell along with Zend. Does that mean I cannot sell PHP scripts or web sites that I build?
A. No. Not at all. This clause only concerns software built around the Zend scripting engine library, not scripts that PHP executes, using that library. You are free to distribute PHP source code you write freely or commercially, without any concern about the PHP or Zend licenses. You may also package PHP as a whole with your commercial applications as much as you want. You just can't build commercial applications that use the Zend scripting engine library directly.
Q. So, what's the point of the Zend license? When should I be concerned about it?
A. You should be aware of the Zend license in two cases. First, if you publish patches to the Zend scripting engine library. The Zend license allows Zend Technologies, Ltd. to use those patches royalty-free (see the license for exact details). Second, the license prevents commercial use of the Zend scripting engine library to build commercial applications. If you want to use the Zend scripting engine library commercially (for example, as a macro language in a commercial word processor you're writing), you must contact for licensing information.
Q. Where can I get more information on the QPL?
A. The authors of the QPL, Troll Tech AS, have published an annotated version of the license which makes it easier to understand. You can view it online .
Q. You suck! I'm going to take the last version of PHP 3 that was distributed under the GPL and fork! How would you like that?
A. With fries.