Prusa now offers two answers to the same question on Printables: what should a creator choose when they want to publish the files for a physical object without giving up every say over what companies do with them?
One answer is already familiar in open hardware. CERN-OHL-S v2 lets anyone manufacture and sell products based on a design while applying strong reciprocity to the source.56 Prusa has just added that license to Printables.1
The other is Prusa's own Open Community License, updated to version 1.1 on June 24, 2026.1 It takes a different path: a non-commercial user receives broad rights to use, copy, modify and share, whereas a business may not commercially replicate the OCL item or its derivatives without a separate license.2
That difference changes more than the strength of copyleft. It changes the licensing family.
Under the Open Source Hardware Association's definition, OCL is not an open-source hardware license because OSHW terms must allow the manufacture, sale, distribution and commercial use of products made from the design files without charging a royalty for those activities.34
Prusa does not disguise the distinction. Its own v1.1 post presents CERN-OHL-S as the option where manufacturing, sale and even AI training remain possible as long as derivatives stay open, then offers OCL beside it for creators who want a different boundary.1
The experiment is therefore more interesting than a naming argument: can a hardware-sharing culture give hobbyists something close to open-source freedoms while preventing a competitor from industrializing the same design for free?
Two users
OCL v1.1 is only 56 lines long in its GitHub repository. Its fundamental split separates non-commercial END USER from commercial BUSINESS USER; permissive versus copyleft is almost a secondary question here.2
The first group receives broad rights. A user may use, copy, modify and “hack” the item and its components; if they distribute a derivative, it must remain under OCL. Version 1.1 tightens that reciprocity because v1.0 had allowed some other non-commercial share-alike licenses.2
A business gets a narrower deal. It may use the item and modify it for internal business use, including internal production, so an OCL machine can serve as a tool for manufacturing some other product. What it cannot do is copy or replicate the OCL item, its components or derivatives for a commercial purpose without a separate agreement, apart from internal repair.2
Prusa's examples make the boundary concrete: a company may use an OCL tool to manufacture headphones, while a company that modifies the tool and wants to sell the modified tool needs a business license.2
Calling this simply “hardware copyleft” would therefore miss something important. Conventional copyleft creates obligations when work is redistributed, but it does not reserve commercial manufacture to the original creator; OCL combines reciprocity for derivatives with a commercial boundary.23
Four modules
The visible novelty in v1.1 is a system of add-ons. Prusa calls them plugins; the repository describes them as modular conditions that a licensor can stack on top of OCL.12
There are four today.
GAtt adds attribution duties to non-commercial derivatives. SWAtt adapts the idea to software and asks for identification in the interface and source code. Micro introduces a revenue threshold. RnD restricts a company's internal use to research and prototyping.2
The interface sounds like a permission builder, but the repository explicitly says the opposite: an add-on only adds binding conditions. It never changes, weakens or invalidates a part of the base OCL.2
That matters most with Micro.
One million
Prusa presents Micro v1 as a way to avoid burdening small businesses until they reach a size where a licensing conversation is reasonable.1
Reading the actual text from the base outward produces a less intuitive result. A company below one million euros of revenue does not acquire the right to sell copies of an OCL design; commercial replication is still blocked by the base license.2
Instead, the plugin tightens the other side. Once annual gross revenue over the previous twelve months exceeds €1,000,000, including affiliates, the business may not use the item, its components or derivatives “in any way” without a separate business license.2
So Micro is not a commercial exception below one million. It removes some free internal-use rights above one million.
RnD works in the same direction by redefining permitted internal business use as research and development only. A company may experiment and prototype toward an independent creation, but using the OCL item for manufacturing beyond that purpose requires another agreement.2
The plugin system is interesting as license design because it makes a creator's preferences explicit and composable. It should be read as a stack of limiters, however, rather than Creative Commons-style switches that each grant a different freedom.
The word open
This distinction is sensitive because open-source communities already attach a precise meaning to commercial-use rights.
OSHWA requires a hardware license to let any party manufacture, sell, distribute and use the hardware and its derivatives, and states directly that non-commercial restrictions are incompatible with open source.34
CERN-OHL v2 was drafted specifically for hardware, received Open Source Initiative approval in 2021, and comes in permissive, weakly reciprocal and strongly reciprocal variants.567 Even its strong variant, which Prusa compares to the GPL, keeps the freedom to manufacture and commercialize; reciprocity applies to the availability of the derived design rather than permission to sell it.16
Prusa appears well aware of that line because Printables now offers both choices, and its article describes CERN-OHL-S as suitable when commercial manufacture and AI use should remain available under reciprocity.1
OCL consequently deserves the name Prusa gave it: Open Community License, rather than Open Source Hardware License.
That is not an insult. OSHWA itself notes that open source is only one way to share information and explicitly supports collaborative models that do not fit its definition.3
Anti-mining
OCL adds another boundary absent from conventional open-hardware licenses: without explicit permission, the base text prohibits systematic or automated text and data mining, plus other data collection activity “in relation to the product”.2
That language looks odd in a license that may cover physical hardware, but Prusa's article makes the intention easier to see by contrasting it with CERN-OHL-S, under which the company says files may be used to train AI models.1
Creators may genuinely want such a restriction. It simply moves OCL further from the open-source principle that a licensor should not choose permitted fields of use.
Why invent
The more useful question is why write another license when CERN-OHL already exists.
Prusa's answer is fairly concrete. It wants repair, modification, learning and community remixing to remain possible while treating a manufacturer that downloads public files and industrializes an exact commercial copy as a different relationship.12
The company also connects the project to patents and registered designs. Its post cites a challenge to a US design patent covering Soozafone's Lucky 13 and argues for contractual tools against appropriation, vendor lock-in and patent trolling.1
The result looks less like a universal freedom license than a contractual boundary around a community: broad rights within certain uses, negotiation once replication becomes a business.
That is precisely the problem traditional open-source licensing refuses to solve by distinguishing small companies, large companies and hobbyists. It grants the same core freedoms to everyone, using copyleft instead when the author wants improvements to remain shareable.36
Prusa has chosen the other compromise.
A laboratory
That divergence makes OCL more interesting than another non-commercial badge pasted onto a CAD file.
Version 1.1 recognizes that a hobbyist fan shroud, a university research instrument and an industrial product may have very different creators behind them. Its modules try to make those preferences explicit, versioned and inherited by derivatives.12
It is also a governance experiment. Only add-ons defined in the official repository may be attached; each has its own version and downstream derivatives must keep them.2 That prevents every upload from inventing another custom clause, at the cost of creating a new standard that must be maintained, interpreted and learned.
Prusa says thousands of Printables projects now use OCL and cites research groups at Berkeley and MIT.1 The question is no longer merely whether the text is clever. A real community has to understand the difference between modifying, distributing, internal use, commercial replication, Micro and RnD without turning every 3D file into a small legal consultation.
Perhaps the most mature feature is simply that Printables now places OCL and CERN-OHL-S side by side. Creators can choose between two philosophies rather than pretending they are the same thing.
One says: you may sell, but you may have to share. The other says: you may share, but selling the copy will often require a conversation.
That is not a minor licensing detail. It is two different definitions of what it means to open a physical object.