[OT] some weird GPL licensing questions

[Peter S Galbraith]

Alexander Neundorf <neundorf at kde.org> wrote:

> So here we go:
> AFAIK the GPL mainly says that if you have the binary version of
> something you have the right to get the sources of this version.

Yes, but only _from_ the person who gave you the binary.  If you give
binar+source to party B and party B give a binary-only to party C, then
party C can't force _you_ to give source.

> Does this also mean that I only have to give the sources to people who have 
> the binary version ? 

Not only that, only to those _you_ have given the binary source to.

>                      Of course they are free to give the sources away
> as they want to, but that's another story. 

Precisely.
>                                            And does this also mean
> that I don't have to give the sources to somebody who doesn't have the
> binary and who I don't like (for whatever reason) ?

Yes.

> Do I interpret this correctly ?
> 
> Let's say I (in the case I would be an until now proprietary-only developing 
> software company) would decide to make a library dual-licensed GPL and 
> commercial, I wouldn't *have* to put the GPL sources on a website, right ?

Correct.

> I would only have to ensure that everybody who buys the binary version
> from me is able to get the sources for the binary, maybe he has to
> send me a mail and then I send him the sources. Right ?

Right.

> Would I actually be allowed to sell this software ? 

Selling and licensing are raelly different issues. 
>                                                     I.e. would it be
> ok to say "give me 500 euro and you get the GPL binary library, and if
> you ask for it, I'll send you also the sources". Of course as soon as
> he would have received the sources he would be allowed to make them
> available for free on his webpage. Right ?

Right.

-- 
Peter S. Galbraith, Debian Developer          <psg at debian.org>
                                 http://people.debian.org/~psg
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