I know that over the years many people in the Blender community have wondered about the possibility of changing Blender’s license from GPL to something more permissive, at least in regards to allowing use of commercial plug-ins, using the FBX SDK, etc. Whenever that idea has come up in the past, folks are quick to point out that it would be very difficult to do this, because it would require the permission of all past developers who contributed code to Blender, from the beginning.
Well, I thought that some people here may be interested in reading about how OpenSSL, a core security program used throughout the web and in many other network services and products is now attempting pretty much this. 20 years old, with 31,000 commits from 400 contributors, they are attempting to contact every single one of them to ask their permission to change licenses. You can read a little more about it here:
There are some significant differences between OpenSSL and Blender, however:
OpenSSL currently has a custom license that apparently is not well-tested (legally) or very compatible with other open-source licenses, while Blender’s license (GPL) is very well-tested and well-understood.
OpenSSL occupies a core position in internet communications technology, so it is used, supported, and contributed to by many major companies (ex: Oracle and Intel). Blender is not nearly as central to CG technology, at least not on a commercial basis like OpenSSL is to its market.
I’m not sure how many contributors have added to Blender’s source code over the years, but Blender appears to have a lot more total source code than OpenSSL (makes sense given the different nature of the two programs). OpenSSL’s source code download is about 5MB, while Blender’s is about 42MB (both gzipped).
Because of all of the above, it’s likely that it would be easier to rewrite any code in OpenSSL that is not approved by its contributors than it would be to do the same in Blender. More motivation and resources, less code to rewrite.
One other thing to keep in mind is that if you read that comment thread, you will see that there is already some grumbling about how they are going about asking the contributors’ permissions (i.e. if you don’t respond, we will assume that you approve). They may end up with some challenges on their hands, as this type of arrangement doesn’t seem to have much legal strength according to some commenters.
Contacting every contributor would be a very difficult task for Blender (especially when considering that a few are from unstable areas of this world). That is only the start though, you would also need a consensus among all of those developers (and a number of them, including active ones, have a preference for working with GPL code).
Essentially, it means that unless large parts of Blender get rewritten, the GPL effectively locks it in forever because of its size and the amount of time passed since the open-sourcing (and even a fork like Bforartists cannot do anything about it). The best that can be done is for the BF to promote the wide use of open standards (such as the OpenCollada format) with licenses friendly to both copyright and copyleft (such as the Apache 2).
Though there’s also the concept of re-licensing certain areas of Blender as they get overhauled so there can be at least ‘some’ direct integration to commercial technology via plugins (if the code it can plug into is sufficient), but I wouldn’t be surprised to not see the BF wanting to go with that.
Relicensing parts of Blender is not a way to circumvent the GPL. Let’s say I write a modified version of Cycles that uses Nvidia’s OptiX SDK. I would be able to redistribute that version of Cycles, but I would not be able to redistribute any version of Blender that integrates that version of Cycles. When parts of Blender are under the MIT, BSD or Apache license, it only makes it easier to use those parts outside of Blender, but it doesn’t make it easier to add anything into Blender.
There’s another precedent, which is the VLC relicensing, going from a strong copyleft license (GPL) to a weaker copyleft license (LGPL).
The problem with the OpenSSL license is opposite to Blender: It uses a custom license that is also unfriendly to FOSS, as it contains this clause:
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young ([email protected])"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
That arguably makes it non-free software. It is considered incompatible with the GPL. Also, smiley-faces and spelling errors don’t belong in a software license.
It’s unlikely that any contributor would have a serious contention with changing this license to something standard.
For Blender on the other hand, the weakening of the copyleft aspects may lead developers to oppose the change, meaning all their contributions would have to be removed/rewritten.
To even get that far, there needs to be intent on the side of the BF perform a license change. I don’t believe that’s the case.