reBot-DevArm is not open source

[abetusk]

In your README, you write:

reBot-DevArm: Open Source Robotic Arm for All Developers

The LICENSE your provided has a non-commercial clause in it.

The "non-commercial" clause makes this project not open source, in the common usage of the term "open source".

"Open source" has a generally accepted meaning of being able to use the digital artifacts for commercial purposes. The OSI and Wikipedia's entry on open-source licensing both articulate that commercial re-use is a (generally accepted) requirement of an "open source" license.

Keeping the term "open source" while having a non-commercial clause in the licensing can cause confusion for people wanting to use your project.

If the intent of the project is to create a libre/free/open source software and hardware robot arm, please change the licensing terms, both in the README.md and in the headers of the source files to reflect this. For example dropping the non-commercial clause would make this project open source.

If the intent is to keep the non-commercial clause of the license, indications of the project being "open source" should be removed as it is not open source.

[ZhuYaoHui1998]

Thank you for taking the time to read our README and providing this valuable feedback!

Yes, we are aware that the OSI Open Source Definition (OSD) Section 6 explicitly requires that a license must not restrict any particular field of endeavor, including commercial use. Therefore, from the strictest perspective of OSI-approved licenses, a license with a Non-Commercial (NC) clause does not qualify as "Open Source".

However, the term "open source" is often used more broadly in the developer community, hardware projects, and everyday practice to mean "source code/design files are publicly available, modifiable, and learnable", rather than strictly complying with all 10 criteria of the OSI definition. Many open hardware projects (such as robotic arms and 3D printing designs) use the CC BY-NC-SA license precisely to protect the creator's commercial rights while encouraging educational and personal use.

The goal of reBot-DevArm is to "lower the barrier for all developers to get started with Embodied AI and robotic arms". We focus on providing complete hardware blueprints (STEP files, 3D printing files, sheet metal parts), detailed BOM lists, and software SDKs (Python, ROS, etc.). All of these materials are fully public — anyone can freely download, study, and modify them for personal, educational, research, and non-commercial projects. We have not hidden any core files nor set up any paywalls. This is actually more open than many "open source" projects that only release partial code.

The OSI definition is primarily for software, while reBot-DevArm is an open hardware project. The open hardware community (such as OSHWA) allows more flexibility in licensing. Many projects use the CC-NC family because physical products involve manufacturing costs, supply chains, and intellectual property protection.

We chose CC BY-NC-SA 4.0 because we want to:

• Allow sharing and modification (Attribution + ShareAlike)
• While retaining the right to commercial manufacturing/sales (Non-Commercial)

This approach is very common in the hardware domain and does not hinder community collaboration and learning.

If the community strongly desires, we are open to considering:

• Updating the README to more clearly distinguish: describe the design files and code as “Source Available + Non-Commercial Use” instead of strictly claiming “Open Source”;
• Providing a separate commercial license (dual licensing) — companies interested in commercial use can contact us for discussion;
• Or evaluating a switch to more permissive licenses in the future (e.g., Apache 2.0 for the software part + CERN-OHL for the hardware), though this would require internal discussion.

We welcome everyone to share specific use cases. For educational, research, or personal projects, we are more than happy to provide additional support or documentation.

You mentioned the “common usage of the term open source”. In hardware robotics projects, many people indeed consider “making all source files public” as open source. What kind of license do you think would be most suitable for this kind of education-oriented robotic arm project? We would love to hear the community’s opinions.

Ultimately, our purpose is to help more developers easily get started with robotic arm development, rather than getting stuck on licensing terminology.

Looking forward to your thoughts and suggestions!

Best regards,
Yaohui

[abetusk]

You are mistaken on many points. I will try to address them below but I would like to stress the overall point of representing your project earnestly. Whether you agree or disagree with the commonly held usage of "open source", labeling your project as open source, while retaining a non-commercial clause, does not accurately represent the allowed usage of your project and can cause confusion for anyone wanting to use it.

Yes, we are aware that the OSI Open Source Definition (OSD) Section 6 explicitly requires that a license must not restrict any particular field of endeavor, including commercial use. Therefore, from the strictest perspective of OSI-approved licenses, a license with a Non-Commercial (NC) clause does not qualify as "Open Source".

The Open Source Definition, published by the Open Source Initiative (OSI), has Free Redistribution as it's first point. Here is the section in it's entirety:

1. Free Redistribution

The license shall not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programs from several different sources. The license shall not require a royalty or other fee for such sale.

The non-commercial clause restricts other parties from selling software and does not meet the first point listed in the The Open Source Definition.

However, the term "open source" is often used more broadly in the developer community, hardware projects, and everyday practice to mean "source code/design files are publicly available, modifiable, and learnable", rather than strictly complying with all 10 criteria of the OSI definition. Many open hardware projects (such as robotic arms and 3D printing designs) use the CC BY-NC-SA license precisely to protect the creator's commercial rights while encouraging educational and personal use.

The usage of "open source" has consistently meant available for commercial use for the past 28 years.

Including a non-commercial clause in the license prevents it from being open source hardware or open source software.

The OSI definition is primarily for software, while reBot-DevArm is an open hardware project. The open hardware community (such as OSHWA) allows more flexibility in licensing. Many projects use the CC-NC family because physical products involve manufacturing costs, supply chains, and intellectual property protection.

You are mistaken about what Open Source Hardware Association (OSHWA) considers open source hardware. OSHWA is clear about the open source hardware definition. Their document on "Open Source Hardware Definition" clearly mentions the ability to not restrict resale. Here is the appropriate section:

5. Free redistribution

The license shall not restrict any party from selling or giving away the project documentation. The license shall not require a royalty or other fee for such sale. The license shall not require any royalty or fee related to the sale of derived works.

The OSWHA also has a FAQ that reiterates this point:

Licenses that prevent commercial use are not compatible with open-source

You say:

We chose CC BY-NC-SA 4.0 because we want to:
...
While retaining the right to commercial manufacturing/sales (Non-Commercial)

It is absolutely your right to add a non-commercial clause to your license but including the non-commercial clause prevents it from being called open source software or open source hardware.

You mentioned the “common usage of the term open source”. In hardware robotics projects, many people indeed consider “making all source files public” as open source.

Many people having an incorrect understanding of what open source means doesn't change the commonly understood definition of open source software and open source hardware as allowing for commercial use.

What kind of license do you think would be most suitable for this kind of education-oriented robotic arm project?

Whatever my opinion about what licenses should be used in education is beside the point. I'm pointing out your misuse of open source as it applies to your project.

Ultimately, our purpose is to help more developers easily get started with robotic arm development, rather than getting stuck on licensing terminology.

By adding a non-commercial clause, you've forced developers wanting to use your project to consider licensing terms. This is made all the worse if a developer sees the term "open source", mistakenly uses it as open source software and hardware, and now exposes themselves or their employer to legal risk if they use your work in a commercial setting.

Calling your project open source with a non-commercial clause can cause confusion. If you would like your project to retain the non-commercial clause you should remove the term "open source". If you would like your project to be open source, then you should remove the non-commercial clause from the license.

[ZhuYaoHui1998]

Yes, you explained it very clearly, we will talk about this part, we may have misunderstood and most of our efforts are spent on the development of the robotic arm itself., and we will discuss this part.

[adabru]

I'm a software developer. "Open source" in commercially influenced contexts means to me, that I can find the code online and inspect it. Like the Unity Game Engine or Google Firebase, which are both not usable commercially. I still appreciate the available source code very much.

When I read FOSS / FLOSS / libre, or "we love open source", then I expect the project to be "we would never persecute anyone for this project".