Questions? Questions?

Licensing is complex, in particular open source licensing.  A lot of wild opinions circulate on the Web.  Here are some trusted sources you might want to consider.

Contributor Agreement Contributor Agreement

The Contributor Agreement establishes code provenance and shared copyright.  It is mostly modelled after similar contributor agreements by SUN Microsystems (now Oracle), mongoDB / 10gen, and other open source projects.

To execute it, you can download and print it, sign it, and then email it back to us.

Commercial Version Commercial Version

Are you concerned about indemnification against third party claims or patent provisions included in the AGPL v3 license, or do you have a problem with the additional attribution and user name / logo use proivisions?   For additional information or a commercial version of the sipXecs solution, please contact eZuce Inc.

sipXecs Licensing sipXecs Licensing

The SIPfoundryTM sipXecsTM solution consists of several open source components, each licensed under its respective license. If you are a user of an unmodified copy of sipXecs, either installed from the binaries we provide or built from source, you have no obligations and you can ignore the rest of this page, except for permitting SIPfoundry to use your name and logo to identify you as a user.

  • sipXecs is licensed under the Affero General Public License (AGPL) version 3 or newer
    For questions about licensing contact SIPfoundry or eZuce
  • Certain libraries that are part of the sipXecs project are licensed under their respective open source licenses

Our goal with using AGPL is to preserve the concept of copyleft for sipXecs. With traditional GPL or LGPL, copyleft was associated with the concept of distribution of software. The problem is that nowadays, distribution of software is rare: Software applications tend to run in the cloud. AGPL fixes this "loophole" in GPL / LGPL by saying that if you use the software over a network, you are bound by the copyleft. Other than that, the license is virtually the same as GPL v3.

If you modify sipXecs in any way and distribute or provide access to your modified version over a network, you are required to release the full source code for the modified version, including the build system.

Licensing Information

The licensing information provided by sipXecs is as follows:

Copyright © 2004 to 2012 SIPfoundry Inc. 

Certain elements licensed under a Contributor Agreement. Contributors retain copyright to elements licensed under a Contributor Agreement. 

Licensed to the user under the Affero General Public License (AGPL) version 3 or newer. 

The SIPfoundry and sipXecs names and logos are the property of SIPfoundry Inc. an may not be used without permission. 

In addition, by downloading and / or using the sipXecs solution, you agree to the following additional terms:

1) You cannot remove or alter the SIPfoundry copyright notices or attributions to SIPfoundry, Inc.

2) You cannot remove the SIPfoundry and sipXecs logos

3) By using the sipXecs solution you agree that SIPfoundry can use your name and logo to identify you as
    a user of the sipXecs solution


Contributions to the sipXecs project require that you execute a Contributor Agreement.  You can download the Contributor Agreement in the left column of this page.  This Contributor Agreement is essentially similar to the one we used since SIPfoundry was founded in 2004.  The reason for the Contributor Agreement is to establish code provenance (i.e. being able to establish a record where different parts of the code came from).  The Contributor Agreement also establishes shared copyright.  

For contributions to compoenents other than the core sipXecs libraries and applications, contributions have to be made to the respective projects under the licenses applicable and requested by these projects.  In particular, contributions to FreeSWITCH are under the MPL 1.1 license.