http://openacs.org/about/licensing/open-source-licensing provides a layman's summary of the GPL. The part about derived works says:

"anyone can create a derivative work of the code and redistribute it, as long as the resulting source code is also made available at redistribution time, and as long as the resulting source code is licensed under the terms of the GPL."

There's a bunch of other pages that try to summarize the terms of the GPL, e.g.: http://drupal.org/licensing/faq

Of course, your best bet is to consult with a copyright attorney.

On 02/01/2012 12:24 AM, Prashant Shewale wrote:
Hi All,

         I would like to ask if we can use RHQ framework as base for commercial project. I would like to design management software for our enterprise software using RHQ as a base. I know RHQ is licensed as GPL and so its difficult to sell closed source product. Can you please provide me some guidelines?

Thanks,
Prashant 


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