With the pending departure of Chris Buechler, we wanted to find a way to express to the community our continued commitment to keep pfSense® software open source.

As such, pfSense is moving to the Apache License 2.0 in order to align the goals of the project with other (unannounced) offerings from Netgate. The Apache License 2.0 is a permissive license similar to the MIT License. The main conditions of this license require preservation of copyright and license notices.

Where the 2-Clause and 3-Clause BSD licenses provides no direct language around the areas of copyright, patents and trademarks, the Apache License does. The Apache License is very clear that individual contributors grant copyright license to anyone who receives the code, that their contribution is free from patent encumbrances (and if it is not, that they license that patent to anyone who receives the code,) and that use of Trademarks extends only as far as is necessary to use the product. As a reminder, only genuine pfSense software can bear the registered trademark of pfSense. It also includes a patent termination clause, should a lawsuit arise.

The Apache License 2.0 is the third most popular license on github. Android, Apache, Chef, Docker, OpenStack, Salt Stack, and Swift use the Apache License 2.0.

Now pfSense does as well.