Re: Dual-Licensing Linux Kernel with GPL V2 and GPL V3
From: Linus Torvalds
Date: Fri Jun 15 2007 - 13:04:49 EST
On Fri, 15 Jun 2007, Michael Gerdau wrote:
> I find it obvious that the GPL was meant to prevent such to be possible.
> This is what I mean by the "the spirit of the GPL".
Umm. It may well have been meant by *rms*. But your argument fatally falls
down on the fact that rms has had *nothing* to do with the Linux kernel.
> Living in germany I'm also used to the courts valueing the intention over
> the exact wording of a contract (a licence after all is a contract). So
> I _think_ in germany TiVo would have lost a lawsuit if they had tried it.
Ehh. The intent that matters is not the intent of the person who authored
the license, but the intent of the person who *chose* the license.
In other words, rms has *no* input on the kernel.
What matters is *my* intent in *choosing* the GPLv2, not *his* intent in
But to make it even less relevant: intent really only legally matters when
the legal issues are unclear.
And they really aren't that unclear here.
> Anyway, if one considers Tivoisation acceptable then there is no reason
> to stop using GPLv2.
> If one wishes to prevent it there are two related questions:
> - does GPLv2 prevent it ?
> - if GPLv2 does not prevent it then how can we change it to achieve that ?
Well, I think it's fairly unquestionable that the GPLv3 does prevent it.
So your second question isn't even really interesting. We know the answer.
So the only question that is even remotely interesting is the first one.
> To me it seems as if the FSF tends to answer the first question with 'no'
> and consequently answers the second question with 'GPLv3'.
Yes, I do agree with that reasoning, but there are *other*, and more
direct, reasons than just the FSF's answer to say that the answer to your
first question is "no".
The fact is, plain reading of the license (which *always* takes precedence
over "intent", even in Europe) simply doesn't make what Tivo did illegal.
You literally have to read the GPLv2 in ways that are obviously not true
to get to any other situation.
For example, Alexandre made the same two mistakes over and over in his
reading when he tried to argue that the GPLv2 disallows what Tivo did:
(a) The right to modify means "modify in place"
This was a point that Alexandre (and others) have tried to make, but
it really is *not* supported by any reality.
First off, the GPLv2 simply never *ever* says "in place". That
wording (or anything equivalent) simply does not exist! So you really
have to add it by "reading" it some special way, and quite frankly,
no such reading is sensible.
I can logically *prove* that such a reading is not sensible by the
two examples I already made clear to Alexandre multiple times:
- Red Hat sends out DVD's with GPL'd software, and thus
distributes copies that CANNOT be "modified in place". So
thinking that "modified in place" is made illegal by the GPLv2
is simply untenable, unless you think that what Red Hat does is
against the GPLv2.
Do you really believe that what Red Hat does is against the GPL?
Does Alexandre? Judging by his email address, I don't think he
- I myself distribute Linux by making it available for download
publicly, and no, I do *not* allow people to modify it in place,
even though I do distribute Linux.
Alexandre tried to argue against this point by saying that I'm
not really "distributing" Linux, and that the actual copying is
being done by people who download it, and that they *can* modify
their downloads "in place", but that only shows a lack of
knowledge about what "distribution" means in copyright law.
The US courts have made it very clear that you "distribute"
things not by downloading them, but by making them *available*
for public download. So from a purely *legal* standpoint, I do
actually *distribute* Linux by making it available! And no, I
don't allow people to modify it in place!
Again, do you *really* think that I am in violation of the GPL
by making the kernel available for download (== distributing
it), but not letting others modify it in place?
So clearly, the whole "modify in place" argument is simply *wrong*.
It cannot *possibly* be a valid reading of the GPLv2! When the GPLv2 talks
about "legal permissions to copy, distribute and/or modify" the software,
it does *not* mean that you have to have the ability to modify it in
The other argument Alexandre made was different, but equally invalid from
a legal standpoint:
(b) The language in the preamble: "must give the recipients all the
rights that you have" means really *all* the rights and abilities!
This too is a totally flawed reading of the license, for a few
- It's not actually in the *conditions* section. It's part of the
explanation of the conditions, and while it's part of the
license, it actually *is* different in the sense that it's not
even meant to specify the "precise terms and conditions". Those
are explicitly laid out _elsewhere_ (look for that term:
"precise terms and conditions").
- However, I don't dispute that the language exists, I just
dispute Alexandres _reading_ of it, and I offer an alternate
meaning for it. I do not guarantee that *my* reading is the
correct one (although practically speaking, I pretty much can
guarantee that too), but I *do* guarantee that Alexandre's
reading is wrong, because it is nonsensical and impossible.
It is nonsensical and impossible in the exact same way I
showed that he was trying to claim something nonsensical
and impossible in adding the "in place" reading to "right to
- So the reason I want to mention the fact that it is in the
"preamble" is exactly because the preamble is *not* meant to be
the "exact terms and conditions", it's meant to be a much softer
thing - something that _explains_ the exact terms and
In particular, in this case, it explains "Section 6" (and
you could also say that it explains section 7 too, but the
preamble actually talks about patents separately, so you should
probably see "section 6" as just the most obvious example of
what the preamble is talking about).
- In other words, the preamble is just a preliminary and inexact
explanation for the _real_ requirements, which are spelled out
elsewhere, in places like section 6 of the license. And *that*
section actually makes it clear that "all rights" only concerns
the rights SPELLED OUT IN THE LICENSE ITSELF.
Section 6 explicitly says:
"You may not impose any further restrictions on the
recipients' exercise of the rights granted herein."
and that is what I claim is the *correct* and exact reading of
the explanatory language in the preamble. Yes, it is "all
rights", but it is "all rights" ONLY AS FAR AS THE GPLv2 itself
is concerned! It's not about any _other_ additional rights you
may have outside the GPLv2!
- To finish that point, let me just point out that Alexandre's
reading *cannot* possibly work!
In particular, reading the preamble to mean that you give the
recipient *all* rights you have (even outside the actual
requirements of the license itself) that Alexandre tried to
argue, is actually legally simply impossible. The copyright
owner *fundamentally* has more rights than any licensee, and no
license can *ever* transfer all those legal rights!
In other words, Alexandre's reading of the preamble is simply
not legally tenable, because it assumes that the license says
something that simply is not legally possible. And obviously the
license doesn't say anything like that at all: it's a legal
document, it can only state legally valid things!
I'll use the *exact* same examples as previously to show how
Alexandre's reading of "all the rights that you have" can not
possibly be correct:
(a) Again, Red Hat makes DVD's that contain GPLv2'd programs on
them. Red Hat is bound by the GPL, so each work they put
on the DVD is always under the GPL, and Red Hat *must* give
you the rights that the GPL specifies.
But does Red Hat actually give you *all* the rights they
hold on the DVD? No, they definitely do not. They hold a
compilation copyright on RHEL, and they very much do *not*
give you the right to copy the whole distribution and sell
it as RHEL. You only get the rights to the individual
pieces, not to the whole thing!
(b) Again, I make the Linux kernel available to you on a web
site, and thus distribute it to you. Do I actually give you
*all* the rights I have in it? Hell no. I cannot (and do
not even want to). As an author, I have special rights in my
code that you do not get. You get the rights spelled out in
the GPLv2, and *nothing* more.
In other words, Alexandre's reading of the text in the preamble is
*impossible*. It absolutely *cannot* be the way the license works.
It's not how Red Hat itself reads it, and it's not how it can even
legally be made to work even if somebody *wanted* to read it that
See? Both of Alexandre's arguments about why Tivo did something "against
the license" were actually totally bogus. Neither of them was relevant,
they both hinged on Alexandre reading the GPLv2 *wrong*.
> Whether or not the GPLv3 is truely an acceptable answer to prevent
> Tivoisation is a completely different issue that I can't really judge.
Absolutely. I do think it prevents Tivoisation, but I personally think
it's unacceptable in even *trying* to prevent it, and as I've tried to
make clear, the GPLv2 definitely did *not* prevent Tivo from doing what
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