Let's say a private company released a popular software product under a copyleft (GPLv3) license. It's business model was offering consulting services and premium features for a fee, which in turn financed the development of the product. Most of the contribution in the projet (>95%) was from employee of the private company. So far so good.

Years later, change of business model: the software is now split between an older community edition, still under the GPL, and a newer commercial version, only available to paying customers. All new development goes in the commercial version and the master branch is not longer available publicy on github.

So my question is: Is such a move legit and compliant with the original GPL3 licence ?

  • Are you asking about the relicensing of the new version of the project (the new non-GPL version), are about the old GPLv3 version that was already released?
    – Brandin
    Jan 21, 2019 at 13:09
  • "All new development goes in the commercial version and the master branch is not longer available publicy on github" - If it was ever available under a GPL license, then someone could have forked it in the meantime and put the fork on Github. You can't get rid of that fork. Or someone could have just downloaded it on his hard drive and later decides to upload the GPL version. Both of these things are permitted by the GPL version you already released, so you can't change what you already released.
    – Brandin
    Jan 21, 2019 at 13:10
  • I'm asking about the relicensing of the project; the GPLv3 code is still available in the old branch. It just that no new developpement will go there, unless somebody fork the project I guess Jan 21, 2019 at 16:03

2 Answers 2


It is not possible under the terms of the GPLv3 to subject a GPLv3 project to proprietary licensing. However, it is possible to receive an alternative license from the copyright holders.

Here, this would require consent from the copyright holders of that 5% of contributions that were not made by employees.

Alternatively, the company could refactor the project to eliminate these 5% of contributions so that the company holds sole copyright. But tracking that part down correctly is tricky, in particular when you consider the copyright status of the company's contributions that are derived of outside contributions.

In anticipation of possible relicensing, some projects require a contributor license agreement (CLA) or copyright assignment so that the maintainer (here, the company) is not limited by the outbound license. However, many contributors may refuse to sign CLAs precisely because of this issue. A recent example of a CLA-assisted relicensing was MongoDB's change from AGPL to the (non-Open Source) SSPL.

There is also the concept of a Joint Authorship. In a work of joint authorship, any copyright holder is able to provide a license without needing consent from other copyright holders, though this may be US-specific. To which degree this might apply to open source projects is subject of discussion. AFAIK no notable relicensing effort has used this as a legal basis, and relicensing typically uses the route of obtaining consent and removing contributions from non-consenting authors.


So, from the ground up...

So the company owns >95% of the intellectual property rights. That's because the employer owns the copyright works created by an employee, unless there are alternative arrangement in place. It's another thing if the employee did not do the work "during the course of their employment".

The Git Repo is going to tell the company who wrote what. What was contributed by the employees will be there in black and white. Line by line.

The company could then:

  1. redevelop the <5% remaining sections of the code (which is GPL licensed) internally by its employees (during the course of their employment) or contractors who assign copyright in their work to the employer company.
  2. They could then licence the entire package on different terms - without the permission of the other contributors. Why? There's no GPL code in it.
  3. That assumes that the <5% aren't willing to assign their copyright to the company, so that they can deal with the copyright as it wishes to as the copyright owner. That could be done with a contributor agreement, or even a one line assignment, supported by consideration, "I hereby assign any copyright I may own in [code base name] to [employer name]".

Moving on to the Split.

So, it mostly depends on the state of the GPL'd code base when it was split between the older community edition and the newer commercial version.

What the company can't do is "unlicence" the versions previously released. See first sentence of section 2 of the GPL (v3). That doesn't mean that the employer must continue to make modified versions available for download.

The condition (section 5, GPL) is:

You may convey a work based on the Program ... in the form of source code under the terms of section 4, provided that you also meet all of these conditions:

When you convey the work (ie make it available to others), you must convey all of it. But you don't have to convey it at all.

So then: 1. if the newer commercial version, only available to paying customers only has non-GPL software in it, it should be kosher for proprietary licensing. 2. there's no reason why they would need to keep conveying a code base to the community at large which does not have GPL licensed code in it.

BTW, there are specific tests to be applied (which are qualitative tests) to determine whether joint ownership of copyright exists in a single copyright work. As said above, joint ownership has different consequences in different countries. In the UK, any joint owner of copyright can prevent any other joint owner from exercising any of the exclusive rights of copyright - ie licence it or continue to licence software under the GPL.

  • A solid answer, thk (if I could I would have accepted both yours and amon's). One thing that strike me is how difficult it is to answer the question in a specific case. You would have to query all the original contributor to know to what they have agreed on and somehow gain access to the commercial version to audit the codebase.... Jan 21, 2019 at 16:09
  • That's one of the things about law. When important (ie relevant) facts the facts change, so does the answer...
    – lellis
    Jan 22, 2019 at 5:00

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