Starting from Zabbix version 7.0, all subsequent Zabbix versions will be released under the GNU Affero General Public License version 3 (AGPLv3). You can modify the relevant version and propagate such modified version under the terms of the AGPLv3 as published by the Free Software Foundation. For additional details, including answers to common questions about the AGPLv3, see the generic FAQ from the Free Software Foundation at http://www.fsf.org/licenses/gpl-faq.html.
Zabbix is Open Source Software, however, if you use Zabbix in a commercial context we kindly ask you to support the development of Zabbix by purchasing some level of technical support. All previous Zabbix software versions up to 6.4 are released under the GNU General Public License version 2 (GPLv2). The formal terms of the GPLv2 and AGPLv3 can be found at http://www.fsf.org/licenses/.
Zabbix documentation is NOT distributed under a GPL license. The use of Zabbix documentation is subject to the following terms:
You may create a printed copy of this documentation solely for your own personal use. Conversion to other formats is allowed as long as the actual content is not altered or edited in any way.
You may not publish or distribute this documentation in any form or on any media, except if you distribute the documentation in a manner similar to how Zabbix disseminates it (that is, electronically for download on a Zabbix web site) or on a USB or similar medium, provided that the documentation is disseminated together with the software on the same medium.
Any other use, such as any dissemination of printed copies or use of this documentation, in whole or in part, in another publication, requires the prior written consent from an authorized representative of Zabbix. Zabbix reserves any and all rights to this documentation not expressly granted above.