Subject:
Re: [discuss] licence problems
From:
Rick Moen ####@####.####
Date:
25 Sep 2008 22:58:12 +0100
Message-Id: <20080925215809.GI13340@linuxmafia.com>
Quoting Jean-Daniel Dodin ####@####.####
> well, we can't discuss if you repetedly challenge the other intelligence.
I am certainly not impugning anyone's intelligence: All of this stuff
is non-obvious, and nobody's born with understanding of it. ;->
> we may have problems to understand each others, but this licencing
> problem is not that easy, that's why I keep dicussing.
>
> the problem is that GPL ask derivative works to have the very same
> licence.
I'm not sure I see the relevance, but: No, that is not the case.
Here is another illustrative example. Again, I find that people get
very confused when they speak in vague generalities, so I use specific
examples to clarify. Let's say back in the late 1990s I coded an SSL
library similar to OpenSSL, but I put it under the new-BSD licence.
Let's say that it's now 1999 and you're in a position similar to that of
my friend Marc Merlin back at VA Linux Systems: You're seeking to add
TLS crypto capabilities to the Exim MTA. You borrow new-BSD-licensed
code snippets from my SSL library codebase, and extend Exim's
SMTP-session modules to use my code. You now issue the resulting
derivative work, which includes some of Phil Hazel's GPLed Exim code
plus some of my new-BSD code, in a tarball. The tarball therefore
includes Phil's copyright statement, plus mine. The various .h files
indicate more-or-less who wrote what.
You've created and distributed a derivative work, something that
requires permission from affected copyright owners. Have you violated
anyone's copyrights? No. My new-BSD licence statement on my SSL
codebase permits what you've done. Phil's GPLv2 licence statement on
Exim has not been violated, either, because my new-BSD-licensed code
that you've borrowed doesn't impose "additional conditions" above and
beyond those of GPLv2 on the derivative work.
Is the tarball under "the very same licence"? No, it's not. My
new-BSD-licensed code fragments are still new-BSD-licensed, and anyone
who can pick them out of the derivative work has every legal right to
use them elsewhere under new-BSD. The code from Phil Hazel's upstream
standard Exim codebase remains GPLv2-licensed.
> This have sense. This is the main interest of GPL!
>
> so what will be the licence of the derivative work?
_Which_ derivative work are you asking about?
If you're asking about a derivative work that includes, say,
GPLv2-licensed code and new-BSD-licensed code, then those remain
available under their respective licences, to the extent they can be
distinguished.
The real, critical question is: If third party X makes a particular use
of a particular bit of code, does any of the affected copyright holders
have cause for a complaint of copyright violation? In the
above-described case, X might decide that your "glue" code that extended
Exim to use my new-BSD-licensed SSL libs is useful in his own
MPL-licensed Web server, so he borrows and reuses it, believing it to
be available under new-BSD.
Does Phil Hazel have just cause for complaint about X having violated
his licensing terms for Exim? Probably not. It's unlikely that X has
borrowed copyright-entitled elements from Exim, and therefore X probably
doesn't need to comply with GPLv2 concerning his borrowings. If X wants
to be perfectly, 100%, paranoically safe, however, he'll instead borrow
only from my upstream new-BSD-licensed library code, and create his own
"glue" snippets similar to what you wrote.
> If you have dual licencing, you allow people to choose what ever he
> want for the derivative work, you don't ask him to keep the dual
> licencing, so this licence style don't stay in the derivative work
Again, you are incorrect. The recipient does not own the copyright
title, and therefore cannot change what terms he passes on to others.
Dual-licensing merely allows the recipient to choose which of two
alternative sets of conditions he/she satisfies, in order to enjoy the
(otherwise-reserved) rights of redistribution and creation of derivative
works.
> usually an author choose a licence to allow freedom, but only limited
> freedom dual licencing give more freedom than any of the two.
That is correct but I'm not sure what your point is. Again, for
purposes of clarity, I am going to use an example:
Concerning the WordPerfect for Linux FAQ, if you download a copy and
wish to do something requiring permission from the copyright holder
(redistribution or creation of derivative works), you are required to
satisfy the conditions of _either_ GPLv2 _or_ CC BY-SA 2.0 or later.
Any copy of my work, or any derivative of my work, must pass along my
conditions of use unmodified: the portion of the passed-along document
written by me must continue to be available to recipients under the
conditions of _either_ GPLv2 _or_ CC BY-SA 2.0 or later.
> simultaneous licencing is not possible (you can't satisfy both
> inheritence condition)
I'm sorry to say that I'm not sure what you mean in the above sentence.
