Hi everyone,

I’m developing a bunch of libraries and software as I've found th big three(Unreal, Unity, and Godot) to have technical limitations or licensing restrictions that I don't like, and I want to open up my own to the greater game dev community, but I need advice on crafting a license that balances open-source principles with flexibility for proprietary use. My requirements are as follows:

1. Modification Contributions: Similar to the AGPL, any changes, wrappers, or functionality extensions must be contributed back to the project under the same license.
2. Linking Exception: Purely using the library as a dependency (statically or dynamically linking) without altering it should not impose the AGPL’s terms on the larger project. This is important for cases like game engines linking to the library.
3. Dual Licensing for Proprietary Use: I’m open to dual licensing:
   • Free use under the AGPL-like terms.
   • Paid proprietary licenses for companies making over a certain revenue threshold, allowing them to keep their projects proprietary(Thinking something like a small percentage revenue share if a company make a lot of money, say over X amount annually, with projects developed with the software to force them to give back in some way if they want to remain closed source).
4. Development Guardrails: Proprietary users should not:
   • Patent features they add to the library and block me from integrating similar functionality.
   • Impede my ability to evolve the library.
5. Specific Case – Game Engines: Games built using an engine that incorporates my library shouldn’t inherit the AGPL solely due to static or dynamic linking.
   

I like how Qt handles dual licensing, but I’d appreciate guidance on how to adapt or create a license that meets these needs. If anyone has experience with similar licensing challenges or suggestions for existing frameworks to use as a base, I’d love to hear your thoughts!

Thanks in advance!

This is really something you need to discuss with a lawyer, probably several lawyers. Creating open agreements like this is tricky, filled with all kinds of legal subtlety that varies all over the globe.

I'd start by selecting what you like and don't like out of the system at ChooseALicense, looking over what they give and what they require of you. Study those out, and bring them with you in your starting discussions with your lawyer.

And if you can't afford a lawyer for this, then you can't afford to publish it that way.

@undefined I have a few grand set aside(and can save and invest more if that's not enough), and some rough drafts for a license that I've written but I've been unable to find a lawyer willing to spend even a few hours to review it. I've contacted a half dozen firms at this point and am at a bit of a loss. They won't even give me a quote…. That's why I was hoping to ask folks here if there was anything they were familiar with that was closer to what I'm looking for. I've looked through ChooseALicense a lot and sadly nothing seems to really fit quite right. Like I said the closest is the AGPL, but I want those exceptions to make sure it's still usable to companies, while ensuring they can't exploit my work and drive me out of business. I like the concept of the LGPL, but the way it doesn't treat networking as distribution, and the way if forces dynamic linking(which can be less performant than static linking with LTO) is really a dealbreaker. And I would like that dual license system for Proprietary software. Ahhh…. it's so frustrating… I just want to make my games, and tools. Not be doing legal…. I'm tempted to just release it under the AGPL for now… but then I can't accept any contributions back into main until I at least figure out a dual license mechanism as the GPL is inherently incompatible with proprietary software, and I would need every external contributor to sign off on it to convert to a different license which isn't feasible…. Maybe I'll just keep it all closed source……

Skyler_Spellbow said:
I've been unable to find a lawyer willing to spend even a few hours to review it.

You could try the list of attorneys here in the Business and Law forum.

https://www.gamedev.net/forums/topic/644761-game-attorneys

https://www.gamedev.net/forums/topic/685751-guide-to-legal-needs-38-prices-by-videogameattorney

(the “38” in the URL represents an ampersand). The list is old but that just means the attorneys listed have even MORE applicable experience than they did when the list was new.

Thank you so much, I hadn't heard of any of these, I will look into them!