It is currently midnight in its Time Zone, should we wake him up for this so much urgent purpose?
You could, for example, use messaging system from the forums, his website, his Facebook …
Don’t worry, he will have the notifications, nothing is urgent as everything is already clear.
The “third party” should understand terms of the the GPL-3.0 license especially when there are now TL;DR sites to make it easier to understand, like the one I sent you.
@KonstantinDmitriev is the maintainer of the project, he is himself subject to the license GPL-3.0 and can’t re-license it as per the terms of the license itself, as he is not the “Sole Copyright Holder”.
So he will give you the same answers as those ones.
That’s why there are licenses, to make the things clear for everyone, and it is not specific to Synfig.
Short answer from Google:
GPLv3 is a strong copyleft license that generally prohibits closing source code when distributing software, requiring modifications to be released under the same license. You can only make GPLv3 code closed-source if you are the sole copyright holder or use it privately without distribution.
Key Aspects of GPLv3 and Closed Source:
- Copyleft Requirement: If you distribute a modified version of GPLv3 code, you must release your changes under GPLv3, making them open-source.
- Sole Copyright Holder Exception: If you wrote the code entirely yourself (no outside contributions), you can re-license your own work as closed-source for future versions.
- Private/Internal Use: You can use, modify, and run GPLv3 software in-house or privately without having to release the source code.
- Distribution vs. Usage: The obligation to share source code is triggered by distribution (“conveying”). SaaS (Software as a Service) where code runs on a server and is not distributed to users is generally not considered distribution under GPLv3, although AGPL covers this scenario.
- Linking: Linking a GPLv3 library to a proprietary application usually requires the entire application to be open-sourced.
If you are not the sole author, you cannot simply take someone else’s GPLv3 code and close it. You would need to remove their code and rewrite it from scratch.
Another answer from Gemini concerning it:
The short answer is no. Under the GPL-3.0 license, a contributor cannot claim royalties for the code they have provided to a project.
The GPL-3.0 is designed to ensure that the software remains free (as in freedom) to use, modify, and distribute. By contributing code to a GPL-certified project, the contributor explicitly agrees to terms that prevent future financial claims on those contributions.
1. Explicit Royalty-Free Grant
When a developer contributes to a GPL-3.0 project, they are granting every user a license that is:
- Perpetual and worldwide.
- Non-exclusive.
- Royalty-free.
The text of the license explicitly states that the rights to copy, distribute, and modify the work are granted without any requirement for payment. Once the code is “in,” the contributor cannot retroactively demand a “per-copy” or “per-user” fee.
2. The Patent Clause (Section 11)
One of the major upgrades in version 3.0 (compared to v2.0) is the explicit patent license.
If a contributor holds a patent that covers the code they contributed, they automatically grant a sub-licensable, non-exclusive, worldwide, royalty-free patent license to anyone who uses the software.
This prevents a “patent ambush,” where a contributor gives code away for free but later tries to sue users for patent infringement to extract royalties.
3. Copyright Ownership vs. Licensing
The contributor still owns the copyright to their specific contribution (unless they signed a Contributor License Agreement or CLA transferring it). However:
- Ownership does not equal the right to demand money.
- By choosing to distribute their work under the GPL-3.0, they have legally authorized the public to use their intellectual property for free, provided the users follow the GPL terms (like sharing the source code).
Comparison Table
| Type of Claim |
Can a Contributor Charge Royalties? |
Reason |
| Usage Fees |
No |
GPL-3.0 Section 2 guarantees royalty-free permissions. |
| Patent Royalties |
No |
GPL-3.0 Section 11 forces an express patent grant. |
| Distribution Fees |
No |
While anyone can sell a copy of the software, they cannot force others to pay royalties for subsequent redistributions. |
Summary for your project
If you are managing a project and a contributor suddenly asks for money for the code they already submitted: they have no legal ground under the GPL-3.0. The license is irrevocable. However, they are free to stop contributing in the future or to sell their services (consulting/support) separately.
