Licensing FAQ

Why do I need to purchase a commercial license when I can get it for free?
If you want to develop an Open Source design, you are welcome to use our Open Source VHDL models. If you don't want to release you design in Open Source (for example to keep your source code secret or to produce commercial designs), you must purchase a commercial license.

I don't want to give away my source code. What do I do?
You must buy a commercial license.

I want to distribute a netlist version with additions and modifications to the Open Source models. Is it enough to distribute the source for the original version?
No, you must supply the source code that corresponds to the final netlist. Corresponding source means the source from which users can rebuild the same netlist. Part of the idea of open source code is that users should have access to the source code for the deign they use. Those using your version should have access to the source code for your version. If you release an improved version of a GPL-covered design, you must release the improved source code under the GPL.

Can we use the Open Source Models while developing our non-open source design and then purchase commercial licenses when we start to sell it?
No. Our commercial license agreements only apply to designs that were developed with our models under commercial license agreement. They do not apply to design that was developed with the Open Source Models prior to the agreement. Any design developed with our models without a commercial license agreement must be released as Open Source code.

What are the differences between the GNU GPL licensed and commercial licensed versions of our product offerings?
The main difference is in what the license allows you to use them for. Certain models and test benches are only available in the commercial versions. Finally, our technical support service is only provided for the commercial versions.

What is the idea behind providing Open Source (GNU GPL) versions of our products?
They are our contribution to the open source community. Part of our commitment is to enable those who contribute to open source models to receive something back. We also benefit, as open source users contribute to the quality of the products by providing bug reports and feedback.

Why is there no Open Source (GNU GPL) version of Fault Tolerant (FT) models?
The fault tolerant models have been developed to withstand the radiation effects seen in military and space applications. We regard these applications as specific, with a limited value for the open source community. The use of the FT models also requires deeper interaction with the user, thus the models are only available under commercial licenses.

I want to put the Open Source models, and my design that use the models, on a CD-ROM or on a web site. Can I do that?
Yes. You may copy and redistribute the Open Source models, both at home and at work, without restrictions.

Using the Open Source models, can I make non-open source designs for internal use in my company/organization?
No. Designs developed with the Open Source models are always open source designs, i.e. it can only be distributed under an open source license. In particular, all the source code for all the modules your design is based on, regardless of whether they have been written by you or by others, must be open source design (because of the "viral" nature of the GPL). This is part of our commitment to the open source community, and enables those who contribute to the open source do so without paying license fees.
Although it is possible to develop open source designs for internal use, it is difficult to ensure that such design is used and distributed legally. For example, if your open source design requires any models that impose conditions on you that contradict the conditions of the GNU GPL, including, but not limited to, patents, commercial license agreements, copyrighted interface definitions or any sort of non-disclosure agreement, then you cannot distribute it at all; hence it cannot be given to consultants, employees for their personal computers, subsidiaries, other divisions, or even to new owners.
Consequently we recommend using commercial licenses for all internal development.

Are the Open Source models really free in the GNU meaning of the word?
Yes. The Open Source models are free models both as in "no cost" and as in "free speech". Even more, it is actually available under the terms of the GNU GPL. This means you can link GPL'ed models to it, and you can take code from our models and put it into other GPL'ed models.

The GNU GPL refers to software and programs, how can the GPL be applicable for our Open Source models?
It is possible to apply the GPL to any kind of work, as long as it is clear what constitutes the "source code" for the work. Program and Software shall be interpreted as the design (in EDIF, netlist) of the models and the source code as the RTL design of the models.

Why are the Open Source models not distributed under the GNU Lesser General Public License (LGPL)?
The LGPL is designed to "permit developers of non-free designs to use free libraries" (quote from the LGPL). In other words, if the Open Source models were LGPL'd, companies would not have to purchase our commercial editions in order to make commercial/proprietary software, they could just use the Open Source Edition, free of charge. That would mean we would not get the revenue necessary for improving and extending the models. Note also that the Free Software Foundation discourages the use of the LGPL.