ZK 3 Licensing

This page talks about ZK 3 licensing only. If you are looking for the licensing information on latest ZK products, please visit here.

GNU General Public License (GPL)

ZK 3 and previous versions are distributed under GPL to allow all who wish to use, inspect, modify, and distribute it freely, but without any warranty.

Today the GNU GPL is the most widely used free software license. According to eWeek, Eben Moglen, General Counsel for the FSF estimates that 65 percent to 70 percent of all open-source projects are licensed under the GPL.

We believe in open source software. We believe it is the most effective way to develop, at least, software frameworks. We welcome all initiatives to publish more software under the GPL license, just as we have done.

Dual Licensing Available

ZK 3 follows the dual licensing model used by MySQL, Sleepycat, and other companies. The dual licensing model is based on the principle of fair exchange or Quid pro Quo ("something for something").

The dual licensing model offers you a choice of either a GPL license or a commercial license. The commercial license will exempt you from all GPL obligations. From licensing perspective, we have two different products depending on usage and distribution, though technically they have the same source code.

Commercial Technical Support Available

In addition to public forums, we provide commercial technical support by e-mail with 2 business day response time.

If you are looking for the licensing information for our latest version, please visit here.