GPLv2 vs GPLv3

[Wilbert]

I have been reading about the proposal of GPLv3. I'm still a bit confused about it. Some questions:

1) Suppose you have licensed your code under 'GPLv2 and later', then you can add GPLv2 stuff, but also GPLv3 stuff, right?

2) However, in the latter case your modified code changes from 'GPLv2 and later' to 'GPLv3 and later', right?

3) In that case you can't add GPLv2 code anymore, but you still can add 'GPLv2 and later' code. Right?

4) What i don't get is, don't you need permission from all authors when the license is changed from 'GPLv2 and later to 'GPLv3 and later'? I guess the answer is no, but i just want to be sure :)

[dragongodz]

http://lkml.org/lkml/2006/1/25/273
http://lkml.org/lkml/2006/1/27/339

[Neo Neko]

I have been reading about the proposal of GPLv3. I'm still a bit confused about it. Some questions:

1) Suppose you have licensed your code under 'GPLv2 and later', then you can add GPLv2 stuff, but also GPLv3 stuff, right?

2) However, in the latter case your modified code changes from 'GPLv2 and later' to 'GPLv3 and later', right?

3) In that case you can't add GPLv2 code anymore, but you still can add 'GPLv2 and later' code. Right?

4) What i don't get is, don't you need permission from all authors when the license is changed from 'GPLv2 and later to 'GPLv3 and later'? I guess the answer is no, but i just want to be sure :)

Well this is all a bit premature as all we have seen is a "proposed draft" of the upcoming GPLv3 and not the real thing or even a candidate for it. :p

1. If you license your code under GPLv2 "or later" then your code can be used to the terms of either license. But not necessarily both at once. That could be an issue if for some reason there should be an incompatability or mutual exclusion in the licenses. But that is highly unlikely. It would behave much like today if you claimed your code was under the GPL but never specified a version. People would be well within their rights to use your code via the terms of the GPL or the GPLv2.

2. If you add GPLv3 code to your project the project itself does not fall solely under the GPLv3. Much like today different parts of the same project can be licensed in different ways. As long as the licenses allow such mixing. And as long as the parts can be kept distinct.

3. "See 2"

4. If you wish to distribute an authors code in ways not explicitly declared by the author then you do need their permission. But if the author specifies GPLv2 or later then you are free to distribute the code under the v2 license or the future v3 license. Though I think ettiquet still calls for asking the author to specify/clarrify that.

@dragongodz
Interesting reading about Linus talking about the kernel being under GPLv2 only. That part is insightfull. But much of what he says about GPLv3 is not that usefull. I think it has been covered many places like Groklaw, slashdot, and digg that what Linus is upset over or disagrees with the GPLv3 on was a missunderstanding. The turning over private keys thing has to do with keys for imposing Digital Restrictions Management (AKA DRM) and not a coders personal GPG, PGP, etc keys that might be used to sign or verrify code. So in all likelyhood even if nothing were to change in the final draft of the GPLv3. Then unless DRM were to be included with the kernel in a way that made it impossible to build as a module etc. And some coder was foolish enough to use his own personal crypto key as part of the system then what Linus talks about will be impossible to happen.

[arch_angel16]

If I understand correctly, this is Linus's beef:

-vendor uses GPLv2 code plus custom signing keys to for a set top box
-vendor publishes source code for set top, minus signing keys
-user tries to modify their set-top code, but the box rejects the new build because the user didn't have the keys
-vendor happy, user not-so-happy

GPL3 makes this situation unlawful - vendor can't withold or limit their code this way.

Linus basically thinks "if someone wants to make a locked-down system with my kernel, go for it, it's not my place to be concerned about what people do with my kernel, and the license shouldn't limit what people can do with the code". Stallman thinks "code should be 100% free to modify, and I should be free to do absolutely anything with the toys I buy, else the toymaker shouldn't have access to my code to help make their toys".

Correct me if I'm wrong but that's the issue in a nutshell, right? A difference of ideologies?

[Neo Neko]

@arch_angel16
I think it all depends on the scenario. Custom signing keys could be used and are used in ways to circumvent and violate the GPLv2 license. That is what the GPLv3 is trying to address.

In essence this would actually be of benefit to Linus and the Linux kernel in many ways since the Linux kernel is increasingly becoming used in many commercial products. How easy it is to modify the code. Encrypt and sign the code with a private hidden key and never contribute the code back to the code base as is the requirement of any GPL version. Even the first. Linus will never have to give over his private key. And companies are still free to create signatures using their own. But they will not however be allowed to unequivocally lock everyone else out.

This all covers important subject matter that was not pertinent or common during previous revisions. With the messily written laws floating around today like that DMCA corporate welfare crap etc. It is highly conceivable that it will be used to obfuscate the code and any modifications. And that any attempt to determine compliance etc will not only be slapped down but those doing the investigation will be jailed or sued into poverty once the DMCA enters the equation. The robber barrons are already chomping at the bit to get the DRM-DMCA shield firmly into place. The only way to find GPL or any other code violators will be to nicely ask them if they are violating pretty please or have an airtight case based on circumstantial evidence. The latter already being a dificult thing to do especially for those that are not large corporations with vast legal resources. Once the DRM/DMCA are in full effect even the biggies like Microsoft, Sun, and IBM will have to tread lightly

But if Linus wants to stay with the GPLv2 and it works for him that is fine. No one is going to force the change. And no one is going to force anyone to give out their personal private key unless they did something stupid like using it as the basis for their DRM. :p

And when it comes to that R.M.S. all code should be free crap don't be fooled. That is mostly over played FUD to try and lend credence to the FUD notion of the GPL being viral. Lies upon Lies. R.M.S. Does personally believe that there is no reason for most code not to be free. And I must say I agree. With all the other protections out there what good will competitors having the source do in most cases. You can patent methods or algorithms. And copyright the rest. Allowing others to know how you do it will not really hurt you in most cases. If it's pattented/copyrighted they can't do anything with it without asking you first anyway. And there is no real value in security through obscurity. It's all just anti-competitive roadblocking nowadays. And it's only going to get worse. Think about it. Microsoft has had access to BSD and Linux source for decades now. And they are still making silly mistakes. It really has not hurt them much if at all. And Microsoft has not really benefited.

[dragongodz]

after the response i got from talking about and trying to help with the GPL in the past i wont debate it here anymore. others can debate what means what etc.

the relavant part of the second link was dual licensing which seems pertanent to what Wilbert was asking. infact i will throw another link about that as a final post by me in this thread.
http://lkml.org/lkml/2006/1/27/344

[Neo Neko]

@dragongodz
Yeah dual licensing is always an option. And then there is always the option of mixing licenses where compatable. Which Linus did briefly go into. But on the larger scale I noticed more the now infamous opining of Linus on the GPLv3 that has been all the rage in tech-news and anti-foss sites. :p So I got the wrong idea of what you were implying.

[mg262]

With all the other protections out there what good will competitors having the source do in most cases. You can patent methods or algorithms. And copyright the rest. Allowing others to know how you do it will not really hurt you in most cases. If it's pattented/copyrighted they can't do anything with it without asking you first anyway.That make sense for large companies... but I could envisage small companies or individuals not having the resources to back this up legally. Don't get me wrong... I'm generally in favour of methods being publicly available -- but I think that there are commercial situations where it makes good sense not to do so.

[Neo Neko]

Yes there are "some" good circumstances not to make code public. But they are IMO rather few. If said company is not large enough to envoke copyright and or pattents chances are that they only have 1 or 2 employees and next to no liquid assets. If you have a real case with solid evidence you only need to walk down the right alley to find probono legal representation chomping at the bit to go. Even high class lawyers will go probono for a slam dunk with possibiliy for large payouts in punative damages. So even if you are only one guy with absolutely no liquid assets your statement has some holes in it. ;) Daunting though it might still be.

In the end though the type of companies you are implying are just the type that stand to benefit most by participation in opensource programs etc. Both in what they might have to offer and what they could gain. It will not work for everyone though. There may be legal issues that could arise say if someone making a commercial video encoding app wanted to use the Xvid or x.264 libraries in their program. There could be a conflict with NDA or other imposed license. And then there is the question of how exactly you would have to license everything to be legal for distribution.

[mg262]

That doesn't take into account the sheer stress, hassle and time cost of actually working your way through the legal system... I know of a case of this type that would seem clear as glass to the average programmer but nevertheless took large teams of lawyers and a great deal of time to resolve.

I can see that if a small company has some use for open source material then it might be a very sensible way to go. But if not, they are opening up a risk without gaining anything in return.

Edit: looking back at the thread title, this has drifted OT (sorry)...