Re: Combining GPL and commercial license

[David Kastrup]

Marcin Giedz <marcin.giedz@altvision.pl> writes:

> Hello once again,
>
> <<Thanks Bob for all your suggestions>>
>
> First of all, I've been looking for the most appropriate list for my
> problem and found this one. If I'm wrong and this list doesn't cover
> problems like I have really sorry and I'll unsubscribe immediately.*
>
> I've been searching/googling web sites to find out one question: is
> it possible to use GPL software/part of code in commercial
> application WITH VERY visible caption "THIS part comes from xxxx and
> is based on GPL license"?

Only if the work as a whole is licensed under the GPL without further
restrictions to _anybody_ who you choose to license it to.

> We'd like to have 2 licenses for our products - GPL and
> commercial. But part of code in commercial comes from GPL. This is a
> little bit like Trolltech's double licese - or at least we see it in
> this way.

Contact the copyright holder on the GPLed software.  If you
dual-license the software, chances are that he'll make an affordable
deal with you for the proprietary variant.  After all, you _do_
provide the software also under a license which he has approved.

Even if you only wanted to license proprietarily, you could contact
the author for permission, but in all likelihood the author would
charge a higher price or refuse altogether.

That's just being fair: you want to make a dime by dual-licensing, so
it is reasonable to offer a reasonable portion of that to the author
for dual-licensing to you.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum