You might wish to look at the licensing of the Xara Xtreme software.
They have recently Open-Sourced (and GPLed) Linux and Mac versions of
their drawing program while maintaining a commercial license on the
Windows platform. They were able to do this because they wrote the
software and obtain agreements from other contributors before
incorporating their contributions into the commercially licensed
On Saturday 03 June 2006 11:49, Juhana Sadeharju wrote:
In my software, I have already thought of using a license
which forbids their use in Windows. I don't know the license
details yet; perhaps GPL + restriction.
This hybrid licensing seems to be a reaction to Microsoft's intent to
enter the vector graphics drawing program arena and not really
The contributor's agreement can be examined at
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