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A Case Study In GPLv2 / GPLv3 Compatibility
An anonymous reader writes "A project called OpenChange is working to develop an open source client library for Microsoft Exchange. They are heavily dependent on Samba code for the underlying protocol support and have been forced to move to GPLv3 once Samba moved. This has gotten in the way of legally adding support to other software such as KDE, which is unwilling or unable to go GPLv3." It sounds like all the developers involved expect the GPLv2/GPLv3 issues to be resolved in time.
Update: 10/01 12:26 GMT by KD : Dan Shearer, of OpenChange and the Samba Team, wrote in to correct the anonymous submitter's mistaken implication that OpenChange moved reluctantly to GPLv3. Read on for his actual position.
I'm Dan Shearer of both the OpenChange project and the Samba Team, and I wrote the message on bacula-devel linked by anonymous' original post. I would like to correct the unfortunate impression given by anonymous that OpenChange has been reluctantly forced to change licenses because Samba has moved to the GPLv3. In fact, OpenChange see that the GPLv3 is entirely appropriate for Samba, and OpenChange plans to use the GPLv3 even when not necessarily required to do so by upstream licenses. The move to GPLv3 was one of two license changes we plan to announce on openchange.org in the next few days.
The specific issue highlighted in the post is not a general GPLv3/v2 incompatibility. Code which is licensed under the GPLv2 but no later version is incompatible with the GPLv3. There are a few significant examples of GPLv2-only code, including KDE as mentioned and also the Linux kernel, which cannot be linked to GPLv3 code. That is a matter of policy for those few projects. We would of course be delighted to be able to use their code as appropriate if they change their policy at some point, but we have no complaint if they do not choose to do so. The GPL offers many choices and this is one of them.
Most GPLv2 code includes the words "or any later version", which is a statement of trust by the licensor in the people who create those later versions. The GPLv3 was created as a community effort, a very large and representative community effort, and in that sense many people think that this trust has been maintained. Including the Samba Team and the OpenChange project. If you are unsure about this, go to archive.org and search for "Eben Moglen 2007", which will give you a choice of media and plain text for the summary talk in Edinburgh a day or two before the GPLv3 was released. We respect that there are different opinions on licensing including some who do not like the GPLv3, however it is indisputable that the GPLv3 is very much a community production rather than a statement from the FSF. That fact of community evolution supports the idea that the trust implied by "or any later version" has been maintained.
It might also be helpful to reflect on the history of OpenChange. OpenChange is an independent work from a team led by Julien Kerihuel built on the research and tools produced by the Samba Team. OpenChange has been the direct beneficiary of a lot of effort contributed by the Samba Team over the last four years. We strongly support Samba's use of the GPLv3 as being an appropriate response to the current legal environment.
The thread the anonymous poster linked to was in response to Kern Sibbald of the excellent Bacula project. Kern has his particular views, and we respect those views, but they are by no means general. (Readers may also like to read the entire thread on bacula-devel.) When we look at the numbers at Palamida we find many thousands of projects that OpenChange can link against, besides all the others with compatible licenses such as the Apache license. We don't feel very lonely :-)
Update: 10/01 12:26 GMT by KD : Dan Shearer, of OpenChange and the Samba Team, wrote in to correct the anonymous submitter's mistaken implication that OpenChange moved reluctantly to GPLv3. Read on for his actual position.
I'm Dan Shearer of both the OpenChange project and the Samba Team, and I wrote the message on bacula-devel linked by anonymous' original post. I would like to correct the unfortunate impression given by anonymous that OpenChange has been reluctantly forced to change licenses because Samba has moved to the GPLv3. In fact, OpenChange see that the GPLv3 is entirely appropriate for Samba, and OpenChange plans to use the GPLv3 even when not necessarily required to do so by upstream licenses. The move to GPLv3 was one of two license changes we plan to announce on openchange.org in the next few days.
The specific issue highlighted in the post is not a general GPLv3/v2 incompatibility. Code which is licensed under the GPLv2 but no later version is incompatible with the GPLv3. There are a few significant examples of GPLv2-only code, including KDE as mentioned and also the Linux kernel, which cannot be linked to GPLv3 code. That is a matter of policy for those few projects. We would of course be delighted to be able to use their code as appropriate if they change their policy at some point, but we have no complaint if they do not choose to do so. The GPL offers many choices and this is one of them.
Most GPLv2 code includes the words "or any later version", which is a statement of trust by the licensor in the people who create those later versions. The GPLv3 was created as a community effort, a very large and representative community effort, and in that sense many people think that this trust has been maintained. Including the Samba Team and the OpenChange project. If you are unsure about this, go to archive.org and search for "Eben Moglen 2007", which will give you a choice of media and plain text for the summary talk in Edinburgh a day or two before the GPLv3 was released. We respect that there are different opinions on licensing including some who do not like the GPLv3, however it is indisputable that the GPLv3 is very much a community production rather than a statement from the FSF. That fact of community evolution supports the idea that the trust implied by "or any later version" has been maintained.
It might also be helpful to reflect on the history of OpenChange. OpenChange is an independent work from a team led by Julien Kerihuel built on the research and tools produced by the Samba Team. OpenChange has been the direct beneficiary of a lot of effort contributed by the Samba Team over the last four years. We strongly support Samba's use of the GPLv3 as being an appropriate response to the current legal environment.
The thread the anonymous poster linked to was in response to Kern Sibbald of the excellent Bacula project. Kern has his particular views, and we respect those views, but they are by no means general. (Readers may also like to read the entire thread on bacula-devel.) When we look at the numbers at Palamida we find many thousands of projects that OpenChange can link against, besides all the others with compatible licenses such as the Apache license. We don't feel very lonely :-)
How is this an issue? If KDE2 uses the GPL2, it clearly says "or any future version", which makes it forward compatible with the GPL3, which means it can be mixed with other GPL3 software. I see nothing in the linked article that contradicts this.
To make laws that man cannot, and will not obey, serves to bring all law into contempt.
--E.C. Stanton
My requirements for a software license center around Stallman's original Four Freedoms. Any software I write I want to have those four freedoms protected, both for what I distribute as well as derivative works, but have no other restrictions, either for developers or users.
The GPLv3, I feel, unnecessarily limits Freedom 0, as well as containing additional clauses that do more than protect the four freedoms. The BSD license doesn't preserve these freedoms for derivative works, so it's not my ideal license either. The patent clauses of GPLv2 simply say, "any patent must be licensed for everyone's free use or not licensed at all", which adequately protects the four freedoms, but doesn't make any further restrictions. It's not what I would call an "anti-patent" provision in the same sense as the GPLv3.
Regarding DRM: it is impossible, in my opinion, for DRM to infringe upon the Four Freedoms in a software sense. Software-based DRM cannot prevent users from exercising any of their Four Freedoms, because since they have access to the source code, they can simply remove the DRM portions of the software. For DRM to work at all with open-source software, the DRM must be entirely hardware-based, and, in every case, that exact software will run on modified or alternate hardware. Thus, I believe anti-DRM provisions are out of scope for a software license, because it attempts to dictate what sort of hardware you are allowed to distribute with your software.
What it really comes down to for me is the four freedoms: anything the license does that is above and beyond those four freedoms is something I don't want. Any of the four freedoms it fails to protect is a deficiency. And that's why I've chosen the GPLv2 for my software.
Dlugar
Computer Go: Writing Software to Play the Ancient Game of Go
Where did you get that datum? I think if you read any decent analysis, you'll find that the vast majority of code in active FOSS projects is written by programmers paid to do so. This means that project leaders, i.e. the ones who invest the most in the project have every incentive to think long and carefully about the future of their project, because it affects their professional future, too.
You only see that one solution because you haven't done your analysis properly.
There are very good reasons why more FOSS developers choose the GPL than all the other licenses combined. Perhaps you should investigate those reasons before discarding it as a nuisance.
Crumb's Corollary: Never bring a knife to a bun fight.
I could construct a piece of hardware that will only run an unmodified RHEL3 image, but never actually distribute that image myself. By building and selling that piece of hardware, have I somehow removed any freedoms of all the people running RHEL3? Not at all. They still have access to the source code, they can modify it and distribute their modifications, they can run the code for whatever purposes they want, etc. The only restriction is to the hardware, not the software. Furthermore, there may be very legitimate reasons why somebody might want to ship a piece of crippled hardware that can only run a single image. Even the FSF has recognized that in their DRM exceptions in the GPLv3.
I could agree that some people might interpret Tivoization as an infringement of the first freedom, but a statement so strong as "clearly infringes" I have to disagree with.
Dlugar
Computer Go: Writing Software to Play the Ancient Game of Go