MySource Matrix has been superseded by Squiz Matrix. This site will remain available for archival purposes only; it is not intended as a current source of Matrix information. For all the latest on Matrix, including documentation and release information, visit the Squiz Matrix site.
From version 3.12, MySource Matrix is available through a dual licensing scheme.
You may choose to use MySource Matrix either under the GPL 2 (a copy of the GPL is provided here for your convenience) or under the Squiz Supported Version licence agreement or SSV which you can read here.
The GPL version is open source and free. The SSV is a commercial licence that includes support services and proprietary code. The differences between the SSV and the GPL versions of MySource Matrix are described here.
Versions before 3.12 are available under the Squiz Open Source Licence agreement which is available here.