I am currently investigating Armory and its dependencies to make sure, as much as possible without being a lawyer, that we can legally sell Armory games. I know that this question has been asked before on the forum and the conclusion is that it is perfectly safe to sell Armory games because Armory is ZLib licensed. It is true that Armory is ZLib licensed, but it is also of concern what the licenses of Armory’s dependencies are.
I am using a tool called Fossology to scan every file of Armory and it’s dependencies for licenses and copyrights. I just finished getting the scan results published here so that anybody can review.
There are a staggering amount of individual licenses and copyrights in the Armory SDK that might go unnoticed and it is quite a lot of information to look through. The scan of Kore found 34 unique licenses in 1005 files, and that is only one component of the Armory SDK.
I am going to be going through the scanner findings and posting any concerns here. Particularly we need to be careful of GPL dependencies. I have a contact that has been in the computer industry for 20 years and he warned me and my team when we said that we were using an Open Source engine. He said that if there was anything GPL, even if it was just a tiny NPM package, that we could get shut down. It would be horrible to make a great game, try to sell it, and get sued because there was a GPL dependency in Armory that we hadn’t noticed. I want to take every precaution to make sure that doesn’t happen.
@lubos and @RobDangerous I want to bring you in on this because I think that this is important for allowing commercial use of both of your projects.
Initial Concerns
I haven’t had time to go through the codebase completely yet, but here are the first of my findings.
No copyright in the Armory licence.
The Armory licence doesn’t actually specify a copyright. I am no lawyer, but I think that it would be wise to have the copyright owner specified. I understand that copyrights fall by default to the author of any work, but when it comes to legal matters I believe that it is better to be explicit rather than implicit and it isn’t hurting anything to add the copyright.
Edit: Contributor Copyrights
The license should also include “and contributors” in the copyright statement. As far as I understand, all of the contributors to Armory currently own copyright on the portions of code that they wrote. This is fine, because, if they contributed to the project, they contributed to it under the terms of the ZLib license meaning that everybody can use their contributions under those terms just like the rest of the original codebase.
I think that this does mean that relicencing the project with any license that is not compatible with the original ZLib license would require contacting all of the contributors to get their permission to change the license.
There are other projects such as Haxe which copyright the project only under the organization and do not include contributors in the copyright. This should mean that the Haxe Foundation has the exclusive right to the Haxe codebase and could re-license it however they want to because they are the full owners. If it was desired that Armory be owned exclusively by Lubos or by the Armory organization, then it would probably be necessary to get permission from all current contributors to grant ownership of all of their contributions to Lubos.
Water and World Shader are Licenced Non-Commerically
The licence scan detected two non-commerically licenced shaders for the world-pass and the water-pass shaders. These should be replaced with commercially usable shaders.
Disclaimer
To reiterate I am not a lawyer. While I have done my best to understand the way Open Source projects and licensing works, I cannot guarantee that I have a perfect understaning of the law. Regardless, the point of these comments and my voicing of concerns is to do what we can to help keep the project safe and usable. Even if I may not know for sure the legal details, I think that we can still take precautions and do the best that we can to address what might become issues in the future.