GPL SciTech SNAP DDK License FAQ

SciTech GPL License FAQ
June 2004

In order to ensure that developers are fully aware of how the GPL license applies to SciTech developed code, we are including our GPL license FAQ questions along with the GNU GPL license. Please fully read and understand both the FAQ items as well as the GNU GPL before you use our software. The body of the GNU General Public License is included in this archive as the file LICENSE.GPL.

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Q. What is the difference between the GPL and commercial tools?

A. The GPL and commercial versions of our tools (such as the SciTech SNAP SDK and SciTech MGL) are identical code-wise. The GPL versions of our tools are licensed for development of free or Open Source Software and include complete source code freely available under the GNU General Public License, or GPL.

You can use the GPL versions of our tools to develop software free of charge provided that the software you develop is released under under the GPL license also, or a compatible license as defined by the SciTech FOSS License Exception document (see LICENSE.EXCEPT). If you develop commercial, closed source software, SciTech offers commercial licenses for this purpose. Commercial customers will benefit from professional support services and will not be restricted by the conditions imposed by the GPL license.

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Q. Why do you offer both a commercial and a GPL version of your tools?

A. SciTech has put many years of effort and development into our professional products and development tools. Some developers may not be able to afford our tools financially, so the GPL version of our tools allows those developers to pay for the use of those tools by making their software available to the free software community under a license compatible with the GPL license.

This allows our tools to be used by the largest target audience possible, both those developing free software under various compatible licenses and those developing closed source, proprietary products. The GPL version of our tools also allows commercial developers interested in our tools to evaluate them free of charge prior to beginning commercial development.

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Q. Can I build and design software with the GPL versions of your tools and then release it under the BSD, Artistic or Mozilla licenses?

A. Yes. Although the GPL license is not compatible with many Open Source licenses, we have issued a SciTech FOSS License Exception which allows the use of our GPL covered code with any of the Free or Open Source licenses listed in that document (see LICENSE.EXCEPT).

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Q. Is software based on SciTech's GPL tools really free? Does it carry SciTech license restrictions?

A. Yes, it is really free. No, there are no special SciTech license restrictions on free software produced using the GPL tools. In fact, the opposite is true: The GPL licensing demands that the software developed with the GPL SDK must be free. The receivers of the software must have the rights to obtain the source code, change it, and redistribute it.

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Q. Can I distribute applications that are dynamically linked to SciTech GPL tools?

A. Yes, provided that your applications are released under a license compatible with the SciTech FOSS License Exception document (see LICENSE.EXCEPT). If you do not wish to release your application under a license compatible with the SciTech FOSS License Exception document, then you must license the commercial versions from SciTech. Putting the SciTech GPL code into a library that is dynamically linked into your application does not mean you can avoid the licensing requirements of the GPL license.

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Q. Using the GPL Tools, can I make software for internal use in my company/organization?

A. SciTech's GPL tools are not intended for such use; it is our policy that when you are using SciTech's tools for free, you should in return contribute to the free software community. If you cannot do that, you should get a commercial license from SciTech.

Note that software developed with SciTech's GPL SDK must be distributed as free/Open Source software; i.e. the receivers of the software must be free to give it to whomever they like and must be provided with complete source code. Internal company distribution is no exception to this rule.

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Q. Why doesn't SciTech distribute its SDK under the GNU Lesser General Public License?

A. We do not use the LGPL for any of our tools as that would encourage vendors to take from the free software community without giving anything back. In other words, if SciTech's SDK was released under the LGPL, commercial developers would not have to purchase the commercial versions of our SDK in order to make commercial/proprietary software. Instead they could just use the LGPL version, completely free of charge. SciTech would then not get the revenue necessary for improving and extending our products and tools, which indirectly benefits the free software community.