help with crafting proper license header for a dual-licensing project
A company X which creates a product A, has decided to dual-license their
project under the GPL and a commercial-license. They have asked not to
publicise this until the official release which is why I am using
generic terms - i.e. this is a real question with immediate relevance,
and not a hypothetical one.
They want the source tree to be the same for both editions -- the Open
Source Edition and the Professional Edition. They have called for help
in rewriting the license declaration in their source files. I have
crafted the attached license declaration for this purpose.
Please check and say whether:
1. the license declaration is sufficient for the desired purpose or it
is lacking in any way
2. the license declaration does not conflict with the GPL
3. the license declaration contains anything superfluous which is
already mentioned by the GPL
4. the product so licensed is DFSG-free -- i.e. product A may be
packaged for Debian
Copyright (C) 2007, Company X, Country Y. All rights reserved.
This file is part of Product A Open Source Edition.
This file may be used under the terms of the GNU General Public License version
2.0 as published by the Free Software Foundation and appearing in the file
LICENSE.GPL included in the packaging of this file. Please visit
http://www.companyxwebsite.com/licensing/ to ensure that the use you have in
mind for this file will meet the requirements of the GPL.
This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE WARRANTY
OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
The most important requirement for using Product A under the GPL is that any
works based on Product A -- whether dependent on Product A or derived from
Product A -- must also be licensed under the GPL.
If you wish to base a work on Product A but desire to license it under your own
terms, e.g. a closed source license, you may purchase Product A Professional
Edition from Company X. The Professional Edition is content-identical to the
Open Source Edition but it is licensed under a commercial license, which gives
you -- under certain conditions -- the right to use any license you wish for
your work based on Product A. It also fetches you limited support from Company
X. For details on this dual-licensing policy and the full terms of the
commercial license, please visit: http://www.companyxwebsite.com/licensing/
Users of the Product A Open Source Edition may also purchase support for Product
A as a service, provided the developers' time schedule and workload allows it.
The names of the authors or of the copyright holder (Company X) must not be used
for promoting any product or service which uses or contains Product A. However,
the trademark names 'Product A' and 'Product A Inside' may be used for promoting
such products or services.