Blender is Free Software

Blender is Free Software. It is free to use for everyone. Free to use for any purpose, also commercially. Blender is free to share with others, it is free to study Blender’s sources and free to make new versions.

Blender is free, forever.

This freedom is what makes the GNU GPL license so powerful and it is why it’s much more than “open source”. The license simply prevents anyone to put restrictions on Blender. That protects users as well as everyone who contribute to Blender.

If you decide to contribute to Blender, whether as Python script or as C++ code, you are required to agree on this freedom. You can keep all rights of your own work, but if you publish or sell or share Blender code, you do it under the same conditions, just as Free as Blender is.

The GPL has often be called infectious. I think that’s a negative and misleading frame. Proprietary code is infectious in ways too (try to use proprietary code in your work and face the consequences). Best is to keep the public and open domain entirely separated from your private proprietary domain. And really, both domains can live well together.

You can create bridges between the domains. This is how Blender can work with other proprietary tools or engines. The bridges (if using Blender code) have to be fully GPL compatible. The closed software such bridges lead to can not be bundled, it’s up to your own – or the user’s – concern to connect it.

In the past years, developing and selling Blender add-ons grew into quite a big market. We’ve all seen fantastic & powerful scripts doing amazing things. Great add-on coders indeed. But also: what an incredible API these C developers made for Blender!

Blender’s scripting API is an integral part of the software. Blender add-ons work, look and feel like Blender features. And as with any other Blender feature that means – it has to be free, free and free forever! Paying for an add-on can only mean access to the add-on download service… offering it to you as GNU GPL. Your freedom as a user and developer is guaranteed.

I’ve always interpreted Free Software and the GNU GPL as a means, not a goal. It just works fantastic for Blender. I’m not going to blame proprietary programs for not opening up. But I also won’t accept proprietary business to pollute our open domain. Live, and let live.

And if you think you ‘suffer from piracy’ or find it hard to do business with Free Software? Just distinguish yourselves with the proven successful free/open source business model: provide docs, training, content, frequent updates and support. Your customers will love you!

I expect that all add-on developers recognize and respect this concept. Since 2002 dozens – maybe even hundreds – of people have devoted years of their life to making Blender open and free to use for everyone. This massive effort has made it a strong and exciting program where add-ons can become massively successful. You’re standing on the shoulders of giants!

This can only work if we create a level playing field for everyone. Nobody’s code is more important than another’s. Nobody cuts a corner of the Blender play field to claim it as their territory. Nobody will plant trees here where you can’t climb in or enjoy its fruits.

Complete. Free. Forever.

Please note: I’m not a lawyer and not a license expert. Just sharing how I see this complex matter. Hopefully it helps understanding Blender’s license better. Thanks for reading!

131 comments 96,292 Views
  1. I will reply questions about Blender’s freedom here in the course of the coming days. The discussion here might be moderated for clarity and to make sure it stays on topic.

    • We really need more information, documentation, tutorials and samples how to build add-on and extend Blender (for example how to do a Grease pencil/Sculpting extension. When should be Python used, when C.

  2. I love Blender. I started using it when I was a kid, and I made the terrible tutorials to prove it. I’m excited by the commitment to let a curious kid like him have an alternative to piracy. And to see a massive community grow in support of a progressively more and more awesome tool.

  3. Thank you Ton for this, it’ll help clarify it for everyone. 🙂

  4. When I first heard of GPL, I thought it was a great idea. Freedom would infect the software world until all software would be free and open source! Tada!

    Years later, after participating in and building lots of OSS code, my views have matured. Closed source solutions offer a far wider selection of possible business models, providing economic freedom to creators. Freedom that allows a far bigger selection of projects that are economically sustainable. And for that reason, the copyleft movement will never completely win and replace proprietary software.

    And because of that, if you select a copyleft license, what you’re actually doing is limiting the freedoms of your users, not enhancing them. You’re removing blender as an option for some types of proprietary software. Maybe that’s a worthwhile trade-off for you, but you should have an understanding that GPL does not represent maximum software freedom.

    There is a wide range of OSS licenses which are less restrictive than GPL, which are compatible with proprietary software and the many business models that rely on them. You can use them AND promote a thriving OSS ecosystem for your software. This can in fact grow the size of the community contributing enhancements to the OSS community.

    I no longer believe in the GPL license, and I frequently pass over GPL licensed software because it actually does infect the legal standing of any software you build on it. It’s license is incompatible with lots of other libraries we may want to use to build our extensions.

    GPL is an all-or-nothing solution. Either your whole stack is GPL, or none of it can be.

    Can it work for limited, closed ecosystems? Yes, of course, and a few stand-out examples of that exist, including Linux, WordPress, and Blender.

    But don’t kid yourself. GPL is not the maximum freedom license it pretends to be.

    • From a developer’s point of view the GPL is often complicated, especially if you mix licenses or want to work in the proprietary world. For libraries more permissive licenses (Apache, MIT) work often much better. I just explain how it – at least for us – works well. Especially for users!

      A Blender user has – with respect to the software – a lot more freedom than a Maya user.
      A Blender add-on developer has a lot more freedom than a Maya plug-in developer too. You should read Autodesk’s licenses once. The only “better” freedom you have in the end is the right to limit your users to the max and make them pay. I find the right to take away freedom of others not very “free”…

    • @Eric, don’t blame the deficiencies created due to capitalistic funding on OSS. If there is funding then OSS is superior in every way to closed source. The _only_ argument for closed source is greed. Which is fine, but just be honest about it. The core philosophy of capitalism is the moral justification of greed, and it seems to kinda work for building economies, but so does enslavement and forced labor.

      OSS probably won’t take over because funding is a practical issue that can’t be solved with capitalism in the way. Greed is just too powerful a motivator, and firmly entrenched. But there is not a single project that can’t be completed as well or better under the OSS model if the creators of the project are compensated. One shouldn’t pretend otherwise.

      • I believe one of the points @eric was making was that there are other OSS licenses that are less restrictive than GPL. Not that closed source is free’er.

        GPL is often interpreted to as all or nothing, though packages with mixed licenses do exist.

      • I really can’t agree on that. There is a distinction between greed and will to be paid for time and effort (or investment, in case of companies) You put into developing a software / add-on. Even with Blender – people that work full time on it ARE paid. Does it mean they are greedy? Imho no – they just need to eat and have money for living. Doing something with financial motivation is not the same as beeing greedy.

        Plus, let’s think of it a little broader. Blender is GPL. it’s for free. That’s great, hah? Well, sort of. Guess how much faster the software might grow, how much faster and better all the bugs could be handled, and how many features polished (yes, Cycles baking is STILL a mess – after tens of months) if it has many more developers. But more developers = more money to spend on them. How to get this budget? Well…

        …donations! Right, Blender has a donation system. And it seems to collect enough money to grow. But it’s peanuts compared to, let’s say, Autodesk or Adobe revenue. And it makes the development much slower than it could be with 10x more money.

        Is that bad? Do I suggest Blender should change into prioprietary software? Absolutely NOT! Blender being open source is one of it’s biggest adventages – literally anyone could try it, learn it, use it. No 14-day trials, no limited versions. That’s great! Great, but…

        …but it’s also it’s biggest weakness. OSS = less money = much slower development process. GPL here is and adventage, but it’s adventage that comes with a cost. And we shouldn’t forget about it, cause it will make us blind on the reality.

        I personally chose Blender, partially caus it being free. I accept the fact that it will grow slower than proprietary software. I accept it, but I don’t try to hide it or tell anyone GPL means only adventages and pros. There are cons too, like it or not.

      • So you would rather the developer give his or her work away for free? A developer is worthy of charging for their work, “greed” as you types label everything capitalist is not the goal of the vast majority of developers, making a living is. If you think capitalism is so evil, go live in a socialist country and see how good you have it (not). There is nothing wrong with paying a fair price for good software.

    • GPL gives freedom to the software – thus Free Software.

      Non-copyleft licenses give more freedom to the users – freedom to close down the software.

      I prefer software freedom even if it has drawbacks from the development point of view.

      • I would say the distinction is that the GPL gives the freedom to the users, but more relaxed licenses give the freedom to the developers. And I go with freedom for the users every day of the week.

  5. Great article. I’m fully on board, but I have a question. In the domain you described, the add-ons we buy must be under the GPL license as well? If so, are we allowed to modify the code for special cases and turn around and provide it for free on github, say? If so, would that hurt the revenue for the original developers? I’m just wondering how that’ll work? Should add-on development shift its strategy from “selling code” to “selling services” like support, tutorials, etc?

    • Blender add-ons (Python scripts using the Blender API) have to be GPL license compatible. You pay for the service to download it, not for the software. Never feel bad about harming any GPL developer by sharing her/his code. Sharing is an act of love!

      • Caution: Never assume you can share a Blender plugin package that you have purchased.

        First of all, the code must be licensed as GPL or a compatible license. If the code is not properly licensed, that gives the copyright holders (Blender contributors) grounds to enforce the license – in a court, if necessary. It doesn’t give third parties the right to copy the code.

        Secondly, unless stated otherwise, the GPL only applies to the code. It does not automatically apply to any other content that may be part of the plugin packages, such as: documentation, textures, 3D models, icons or anything that’s “just data”. If such data is required to make the plugin run as intended, it must be replaced.

        Lastly, the GPL does not apply to branding or trademarks. An addon may have a trademark associated, so redistributing it without changing the trademark (e.g. the name and the logo) may be trademark infringement.

        The GPL is not about keeping software “gratis”. This may be a side-effect of the terms of the license, but it is not a requirement.

        • > The GPL is not about keeping software “gratis”. This may be a side-effect of the terms of the license, but it is not a requirement.

          Not a lawyer, but as I understand it, the GPL allows a user who paid for the software to receive a copy of any GPL-licensed material, and then to redistribute it as they see fit. In practice, this means that it is impossible to force a user to pay for a GPL-licensed program.

          • > Not a lawyer, but as I understand it, the GPL allows a user who paid for the software to receive a copy of any GPL-licensed material, and then to redistribute it as they see fit.

            They may redistribute it according to the terms of the GPL.

            > In practice, this means that it is impossible to force a user to pay for a GPL-licensed program.

            There’s a distinction to be made here: If I’m the vendor of a program that happens to be GPL-licensed, I am under no obligation to give you a copy. I may ask you to pay me any amount of money for it. However, once I give you the copy, you have the right (but not the obligation) to give other people a copy, for free or for money, under the terms of the GPL.

            In practice, the cost for giving someone a copy of a GPL program is so low, it can be done at scale without charging any money. This is a consequence of (among other things) the terms of the GPL, but not a requirement.

  6. and that’s why blender can never have AAA 3rd party addons because it’s not a good business model, you’ll have to accept the fact that if you sell one then you have no rights if it gets shared or redistributed or someone else resell it, aslo this is the reason that i see why blender depends on small addons and u have to get tons of them to do the simplest tasks.

    • Mesh Machine and Decal Machine ? Ever heard of those? No? I would say they are on AAA Level and serious Blender Users will buy those, for support and to always be up to date with the new version of those tool sets. Also no Developer is stopped from using for example using Patreon to ask for money to keep developing their Tools. For some this seems to work out quite well. That said..developing software that never actually gets better and only more worse which each version, is also not a good business model. *looks at some of those “industry standard” tools*

      • Actually i know MeshMachine developer , and he complained alot about the license and how his sells has plumbed because of it since anyone can redistribute his addons for free and may stop developement for others only to keep it for himself….that being said my point is about bigger addons that other commercial softwares have that they get released by big studios like ILM /Weta,Ziva Dynamics…etc blender can never have those unless they’re open source which is unlikely to happen.

        • Well it seems that it is planned to support addon devs with the dev fund Blender gets. So maybe that fixes a few things.

    • You don’t have to use Blender, nor do you have to give away your code if you don’t want to. It’s great that you have a choice. Just don’t apply values that work in one domain on the other.

      We further have world class contributors to Blender. I think we can call Blender AAA by now 🙂

      • no one is forcing any values here but just pointing to the obvious…blender may have become AAA by now but saddly it’s addons are far from that, telling me not to use blender or sell addons shows that you guys don’t like it when people point out to a license caveat, not nice…this will only distant future addon developers and even current ones from making big commits to develop world class addons 🙁

        • At no point did he say “Don’t use blender.” He said you don’t have to use it and you don’t have to give away your code.. I see no defensive tone from what he said. More defensiveness from you than anything.

          Keeping everything about using blender free makes it completely accessable to everyone and offers a level playing field no matter if you are a AAA company making games or just some solo person trying to get started.

          Just because people can’t monetize addons doesn’t mean the whole license is terrible. That downside is far outweighed by all the upsides of blender.

          • The thing is that it’s legal to sell add-ons, the GPL allows it.
            Companies and people come to blender also because of great add-ons.
            Once you remove that, you will not have as many people, not have as many funding, so not as many devs on the BF.
            A bunch of great add-ons that will die pretty soon, a lot of add-ons that will never exist, a lot of devs that will never want to try blender, a lot of people that will remove their funding for the BF.

            I wonder if someone will sue Ton for harming their business.
            Even if it’s legal to distribute GPL code that the people bought, Ton said people should do it without thinking of harming the devs.
            Dev is a business, Ton is paid for that, and if you harm someone else business, he can sue this person because of that.
            Like another said earlier, it’s shouting a ball in your own foot , the devs help blender growing, having more people, they pay for the fund, give a part of their sells and Ton disregard them and say that people can hurt them, no worry, I’m paid by the fund, don’t care about others!

            Great Open-source spirit!

    • Everything has it’s downsides and upsides and you probably are correct that there are significant obstacles in developing externally available addons for Blender by VFX giants, which does make such event less likely.
      That, however, is the minor part of the picture and also the upside.
      Heck – even if we disregard licensing at all – the sole act of making production of addons more profitable can be fatal to what blender is at moment.

      • how so? blender is free and it’s developement is separated from addons, nothing is fatal unless it’s devs decide one day not to care anymore, great addons is what actually attracts people to it because vanilla blender is just the bare minimum to get started.

        • It definitely is not bare minimum. I use it professionally all the time and happen to require an external addon a couple times a year. I even don’t customize anything except setting viewport to tracball and zoom to mouse, so my workflow is computer/OS/version independent. But I digress.
          What I meant is that while some motivation to make addons is good, it shouldn’t become worthy of big business. As an example – Imagine someone making their whole living dependent on a single advanced addon. Would you as a developer rise a hand to include the same functionality free into blender, thereby completely destroying income of someone doing good for the community? And would you as the owner of said addon not implement measures to prevent that, especially if you’re a big company? And these things are just the tip of the iceberg. There’s a lot to it.

  7. if you run blender on a server and charge people to use it, it totally avoids GPL


    • Interesting, I wonder if a plugin could upload the a scene to a remote sever, apply some transform to it using proprietary code, then return the result.

      • Oh I see from the GPL FAQ you don’t even need to communicate remotely, you can just open a socket connection to a separate executable on a local PC.

  8. ” You can create bridges between the domains. This is how Blender can work with other proprietary tools or engines. The bridges (if using Blender code) have to be fully GPL compatible. The closed software such bridges lead to can not be bundled, it’s up to your own – or the user’s – concern to connect it. ”

    Hey Ton, are you sure about the later part ? AFAIK that’s not really true.

    • That’s a complicated topic I’m also not fully certain of.
      For good legal advice how to combine the open and closed domains I rather refer to experts from FSF.

      • Yeah, That’s why I linked to the GPL FAQ. I guess it wouldn’t count as proper legal advice, but it’s supposedly maintained by the FSF, so I guess it’s more trustworthy than any other info on internet.

        Anyway, my point is that your explanation about software bridges could mislead some people, since it make it look that as long as you distribute proprietary and GPL software separately everything it’s ok, or that if you distribute proprietary and GPL together it’s not, but it’s not that simple.

        That’s IMO the worst part of the GPL, how nebulous can be in some areas. Maybe a link to the FAQ
        at the end of the text wouldn’t be a bad idea ?

    • The “assembling” part is where it gets into a gray area. Especially as this part of the gpl seems written with c dlls in mind rather than python modules.

      Let me give a concrete example (3 actually)
      1. I was the maintainer of the RenderMan for blender add-on. The way this worked is you had to download the python add-on, which was gpl compliant. And download RenderMan seperately. Then prman was launched as a separate process that the addon talked to through text files and pipes. By any reading I can find of the gpl this is fine. Because there was clear separation and runtimes. But it was limiting in both performance and user friendly installation

      2. Hypothetical renderer X offers a version of blender with X built in. Distributes a download of their blender version but not the source. Clearly a violation

      3. Renderer Y offers a downloadable addon with the python addon part being gpl compliant and a closed source library of the actual renderer. The addon source is available being python and all. There is a clear distinction between the addon code and renderer and no shared data structures. The renderer is launched via a sub process and could clearly be run on its own. This is basically a more convenient version of the RenderMan addon.

      This last example is more of the gray area IMO. But is the one in which commercial add-ons can live happily. While distributing them together is against some of the stricter interpretations of gpl, this seems somewhat pedantic and burdensome to users. And as long as there are no shared data structures or shared memory or making aggregate single programs. And imo this is following the spirit of the gpl. Talking to other addon developers this is an acceptable interpretation To protect proprietary ip. Certianly it is a scenario that is not explicitly spelled out, but I would submit if this scenario was challenged and ruled against in court by blender license holders, then it would quickly be a situation where no commercial renderers would make add-ons which we can all agree is in no one’s interest.

  9. Yeah, distribute all paid addons for free, you will see that the devs will no longer continue to update them.
    Nobody will do it and they will die like many other addons without a dev.
    These devs make their living with addons, they will never make the same amount of money on support, this is ridiculous.
    And the dev fund will never reach that amount of money.
    So, say goodbye to great addons and great addons developpers.
    With that, less users and less funding.
    This is a vertuous circle and you want to break it, you will regreat it for sure!

    • I have to agree that if a dev spends a ton of time developing an add-on, then we shouldn’t be distributing it for free. I understand that this is permissible via the license, but out of respect it should not be done. Furthermore, the add-ons being developed are very reasonably priced on blender market. I also agree that without a dev add-ons die or becomes harder to maintain. An example is the manuel-bastioni lab. It’s an excellent add-on but didn’t find the financial backing it needed. I wonder if the story would’ve been different if it was sold on blender market.

      For tech savvy buyers, they have the option to modify the add-on to fit their need. I have done that. (although then comes the question is how do you share these changes? Maybe we can release the changes as patches, which people who bought the add-on can apply. This way the changes are available for use, if you have paid for the original add-on. Might be a maintenance headache though).

      One thing thought I would not like to see the blender add-ons going down is the yearly licensing fee. I think that model is not good. Thankfully, I have not seen that (maybe there are a few exception). Another thing I love about blendermarket and the add-ons they sell there is once you buy it you get upgrades for free. This encourages me to further support devs as they push out more content.

      I think the donation funding, works well for big projects like blender, but wouldn’t work well for smaller add-ons.

      • OTOH, the same would happen with a proprietary add-on. If the income is too low and the dev quits, the add-on dies. Really dies, with no chance of resuscitation because the source isn’t available.

  10. As add-on dev my point is how to make it sustainable ?

    Take a look at :
    Jackes Luke AN patreon $108 / month
    Pablo Debarro patreon $236 / month
    . . .

  11. Max and Maya have incredible plugins that have a direct impact on the consumer choice.
    Thoses amazing plugins are possible ONLY because enough money is generated from the sales.

    Do you really think that forcing the GPL liscence on addons is really a good idea ? It look more of shooting ourself in the foot to me. No offence, but screaming everywhere on twitter that every plugin ever made for blender should be free at the first place and could be stolen and shared witouth any consequences look like a stupid decision. Tons of great addons could see the light of day. We need to preserve as much as possible their purchasable status, this whole GPL condition for addons need to stay discrete as much as possible.

    An official Blender Market could be put in place in the official website, and 10% of all income could go to the blender foundation. There’s a real gold mine here and we are basically spitting on it.

    I only want what is best for blender, i think that a strong add-on economy is nothing but good things for everyone and i don’t understand how you can disagree on that. Best Regards.

    • Those amazing plugins could simply be the result of the popularity of Maya and Max. In fact, Blender is evidence for that idea, since its improvements have been skyrocketing in proportion to its popularity.

  12. As add-on dev my point is how to make it sustainable ?

    Take a look at :
    Jackes Luke AN patreon $108 / month
    Pablo Debarro patreon $236 / month

  13. Disappointing post. How is proprietary code infectuous? GPL code is decidedly infectuous, it enforces part of it´s license on any software it touches. If you don´t want people to share your code, don´t develop for Blender. Seriously? Would´ve been appropriate to honestly address the downsides of the GPL license. We know how the GPL works and we accept it, because the positive outweighs the negative, but to pretend that the negative doesn´t exist is a bit silly.

    • If you ever get your hands on proprietary licensed code it will *for sure* define it can not be used in an open source project. So it forces you to close up. The Autodesk FBX library is a good example of this too. By design they want it to only work with proprietary tools, with an infrastructure they can control (enforced user registration for example).

      • I think You miss the point. Proprietary software enforces limitations on ITSELF – You can’t use it without permission (in 99% cases: without paying for it). It doesn’t “infect” any other software. For example: I can create an add-on for Maya and distribute it however I like, free or paid, with whatever license (well, most probably ONLY except GPL, but it will violate the GPL licence, NOT the prioprietary software license!). So, the license here is NOT infectious. The license limitations stay with the “main” software and are not distributed (they don’t have an effect on other, dependant software).

        On the other hand, if I make whatever piece of code connected to GPL licensed software, it MUST be GPL too. This way the GPL licensed product infects EVERY other products that need it to work. That’s the definition of “infectious” license.

        What I mean: I love BLender and it’s awesome it’s free and open source. I won’t change it for any other 3D software. But let’s not dive into some weird logic and try to pretend GPL has only adventages – it has it’s downsides too, and it’s not good to try to hide it – both for users, devs and software itself.

        • To build a Maya plugin, you need their developer kit (as described on To download it, apparently you have to create an account on their app store. For that you have to agree to their terms of services. The ToS only allow using APIs provided by Autodesk for internal purposes (ie. without distributing the tools you build on top of those APIs) or by getting a separate developer license (

          That developer license says, among other things: “Your Application must add significant functionality to the Services and may neither (a) offer merely a part of the Services or Autodesk Content or (b) expose any API to any third party, or (c) be a reimplementation or duplication of the Services or Autodesk Content.”

          Sounds pretty “viral” to me.

        • There are proprietary licenses (for modules, libraries, plugins) that “virally” demand the entire project to be license compatible. It’s just in the nature of software licenses.

          I know there are companies (Autodesk included) who would *love* to open source parts of their work, but they can’t because they’re entangled in proprietary licenses from externally used software modules. The sole reason why Blender could open up (in 2002) was my stubbornness to require “let’s code everything ourselves”.

          • Thanks God and You for “Let’s code everything ourselves”!

  14. It truly is baffling to me how so many talented artists and programmers can be so illiterate. It isn’t hard to find out how things work.

    As for the business side of things people are drawing pretty long tangents. You honestly think that there is massive percentage of artists who go “oh wow this paid add-on I use to make my living is GPL so I can download it for free from some piracy site. NICE” ?? You honestly think if it WAS commercial software they’d just go “Awww man it is commercial software I’d better chug up the money instead of finding a cracked pirate version”
    There is huge incentive for people who are actually making a living with something to support that thing. And the benefits of gpl there are not shabby (no need to worry about the creator making it subscription only, if they start insane price hikes anyone can who thinks they can offer better value can fork it etc etc)
    If you want to make an add-on and avoid all the ‘faults of GPL’ (which are going to manifest in exact same form as just piracy anyhow) then just develop it separate as GPL add-on that works with Blender code and standalone add-on that works with the GPL add-on.

  15. Wait.. what? You’re getting paid by the community – passed 2.000.000$ recently if i’m correct – but others should develop addons for free? Are you serious? I’ve switched to Blender primarily because of addons like Boxcutter & Machin3 tools and i was surprised that those creators were charging so little for such an amazing work. And i was happy to pay them. That’s my way to thank them ensuring further development of the tools. Capitalism in its finest form, with no middle man.

    As a guy from former communist country – please do not push your leftist utopian agendas to others. It will always ends up disasterous. We’ve got amazingly creative community & everything seems to work quite well. Do not destroy it.

    • Even proprietary software suffer from “parallel distribution”. We all use some russian site to find torrents. I have bought addons before and it’s because I wanted to support the developer and not because it’s a goods. If you watch the interviews of the creator of GLP, Richard Stallman, you understand that free software is about eliminating the unbalanced power the “developer” have over the user.

    • please do not push your rightist utopian ideas in the first place

  16. While I absolutely agree with the license and its effects on Blender, I also understand that this can really hurt independent programmers who work on addons for Blender.

    On one hand you want Blender to keep being free and not made into a proprietary business and I both understand and agree with that, but on the other it lowers the incentives for community tools that Blender is either missing or could hugely benefit from.

    Earlier you said that both business models can co-exist together, could you elaborate on that?
    How do you propose for things to co-exist better and find some sort of middle ground?

    • Im not certain here, but i would imagine that a developer or developer team could easily change how they make their addons. Make it on platforms like kikstarter and indiegogo where people can fund your team if they like your add on for blender. And then when its developed they charge for each download meaning there are less direct losses from people downloading it once and reselling the download or spreading it for free

  17. It’s rather fascinating to read comments from both people who want less restrictive licencing like MIT so that they can alter and build for circumstances requiring that, and for people who want freedom over their choice of licencing addons to create a walled garden, etc.

    When all is said and done the licencing battle was won by GPL on the first day of freedom when they purchased the rights and released it as such.. there will never be an opportunity to change it so there is no point in arguing it.. the best anyone can do is find a way to work with blender within their context, and it won’t be the tool for all jobs, but it is a fine tool for many jobs.

    This line from ton’s essay makes me very happy “Nobody will plant trees here where you can’t climb in or enjoy its fruits.”

    And what comes across as his conviction to not ‘find a way’ to create divergence within the blender community so that some few people can make bank from all the years of hard work from all the free contributors over the years.

    Thank you Ton for being a stalwart leader on a path that is virtuous.

    • I gotta say, I find your point of view very pragmatic and agreeable. Maybe everyone should just do their best with whatever they have at hand, since the license is not going to change anyway. Dreams of a free world may be utopian, but I’m all for it.

  18. Thank you Ton for made blender GPL.
    I don’t know why be grateful is that hard?
    Stop complain about blender and say thanks to blender community!

  19. Remember that the Blender foundation didn’t always have the budget it does now. It’s not hypocritical that plugin developers have a tricky money making obstacle to over come, because blender developers have the same obstacles.

    I don’t see anyway to enforce addons to be gpl compatible. I can write code and distribute binaries or source code as I please. Distributing it along side blender is another story. In fact it’s possible to make an addon without even having a copy of blender binary or source, just knowledge of the API, and API can’t be copyrighted (in the USA).

    • This is how software licensing works, and it’s legally supported by the FSF and many other organizations. I don’t want people to understand how you can bypass the system, I want people to understand the value of managing a free and open source creation environment for everyone.

  20. Fosi is proud of you.

  21. Just to clarify for those anti-GPL voices….

    One can write (and sell) a proprietary piece of code which works with a GPL piece of code provided that, 1) the proprietary code does not contain any GPL code, and 2) no GPL code is distributed with the proprietary code.

    See if I write a proprietary piece of code as a Blender add-on, I can still in, as long as 1) I do not bundle Blender with it, 2) I do not include any GPL code in it, and 3) I don’t sell it in the Blender store.

    It is no different than me selling a plug-in for any commercial project which has a freely available API and SDK.

    This is a solution which Ton made clear. If one wants to create a bridge that is a free add-on which allows a user to connect proprietary code that sounds/receives data/instructions to Blender, and that add-on is GPLed, then it matters not that the proprietary code is only available for sale. The bridge can be made available in the Blender store, it can be bundled with Blender, but the proprietary code cannot.

    For example, I want to sell a plug-in which takes data from Blender, sends it to Adobe® Premiere®, where in is altered according to some parameters, and sends the results back to Blender. I create a proprietary, commercial, Premiere ® plug-in called, Puree, which contains no GPL code. It sends/receives data/instructions from a Blender plug-in called, Premium Blend. I sell Puree, but I give away Premium Blend for free under the GPL.

    Is this not how it works?

    • Honestly that just seems like an intelligent way to work. No mixed codebases and licenses causing dependency hell. Each part can be tracked and managed seperately.
      Anyhow, the way I understand it is this: Python can hook to other apps via API- in particular, the C family of languages is easy to hook into Python. So the proprietary code could have its own published API, and the Blender addon could simply use the Blender API and the proprietary API to make a bridge… not sure if that is correct.

  22. To my understanding there is nothing that goes in the way of creating a standalone application, sell it and then provide a free addon that makes this app work inside blender. Is this correct?

  23. Thank you so much to make Blender being what it is, and to prevent him falling into the hands of Evil.

  24. i am a bit surprised this got such a big topic suddenly…

    it always has been clear that blender is and will stay GPL licensed and what that means (even if you are not a lawyer it’s basically clear what is ok to do and what is not).

    also… wordpress is in exactly the same position and a lot of money gets made with themes and plugins (which both have to be GPL).

    • The difference is that wordpress guys don’t ask plugins devs to give their plugin for free and to people to share plugin as much as they can :/

      • But as long as the addon contains code that is under this license, then why shouldn’t it be free?

      • Apparently it’s really hard to be clear on this topic. Please don’t think I’m against people who sell add-ons on the BlenderMarket. It’s just like for WordPress – a market where you provide GPL software with service and support. Nothing more, nothing less.

        If you think the GPL concept makes your life as add-on seller hard; try to jump through the legal hoops to make an official approved Maya plugin. Figure out how many people buy it. Learn about how real piracy works. Then we talk again.

  25. Because the license doesn’t say everything must be free.
    You can sell addons under GPL as you can sell themes on WordPress.

    The license was not made to make everything free and it seems blenders user’s don’t understand that.

    Nothing is free, Blender isn’t free, without money, no blender, no Ton, no devs, no open movies, nothing.
    So this is funny to want everything for free when it’s not possible in the first place.
    Someone has to work hours, days, months, years to make it for you to use for free or a small amount of money.
    Ton and the devs get paid to make blender, user’s give to the fund, addons devs too.

    Without money, no blender, without money, no addons that’s just that!

    One thing, Ton, can you tell me how a dev can sell support for addons?
    Hey guy, you downloaded my addon for free, thank you I worked a year on it, I’m proud you like it, but, if you need help, that will cost you money 😉
    Do you really think people will want to pay support for something they had for free?

    Donations don’t work either, support will not and making tutorials is the same, who will want to pay a tutorial to use an addon.
    And if you make a tutorial who has nothing to do to the addon, you don’t make money with your addon, you make money with your tutorial.

    • If a developer thinks the terms under which Blender is distributed and can be extended are so onerous, they’re free to build their app against something that is not Blender.

      Blender is not public domain, and it never was. That money flew in the direction of its developers is immaterial for the question whether any individual plugin developer is entitled to base their work on it under the terms they desire.

      There are numerous ways to enable a path for non-GPL plugins for 3d animation, some keeping blender in the picture, some not. They all require significant effort on the part of those who desire non-GPL plugins: one approach, without Blender, would be to build their own 3D modelling environment that they can write plugins for, and license it differently. I won’t comment on the ones that would enable non-GPL blender plugins, interested parties can figure those out by themselves.

  26. I was answering to Ragnar Aambø

    • You didn’t get the point of what i said. I am talking about the source code, if you use any source code that is licensed under GPL, then it must be licensed under this license.

      • Yes and everybody know about that, especially addon’s devs.
        Why do you come with that?
        And why people come with that actually, even Ton?
        When you buy an addon made with Blender API, you have the source code, it’s not hidden in an island on the other side of the world ^^

        • The GPL doesn’t only mandate availability of the source code, it also mandates additional rights for the recipients of the source code. The most contentious is that they must be allowed to redistribute it under GPL terms.

  27. The GPL license uses the term “free” ABOUT RIGHTS, NO MONEY!!!!!!!!!!!!
    Get that through your head once and for all.
    But no more could be expected from the profiteers than to interpret the term “free” in the sense of “no money”. Besides, I would be curious to know the ratio between the donations made by these demons dev of paid addon (of which I am a part) and those made by the Tinker Bell that claims to use Blender because it is free (for rights) and open source rather than the fact that it is free (no money).
    If today the BF hires more dev than yesterday, it is thanks to the devfund that would not have been launched if the Tinker Bell really had been on Blender for its free (for rights) side and not free (no money).
    In the end, I’m sure that what you have the biggest problem with paid addons is not the fact that they are paid, but rather that you don’t have access to them without paying. When you see the average price of an addon on Blender compared to other softwares like maya and others, you think you’re working almost for glory.
    And finally, no one asks you to buy these paid addons. You can just as easily get into the code, make the addons you need and share them with the community. And there, I think that a large part of you will quickly realize the work that this represents. But you probably won’t recognize him because you’re far too hypocritical.

    • > And there, I think that a large part of you will quickly realize the work that this represents

      Plugin developers could also decide not to violate Blender’s license and build their own 3D modeller instead. “And there, I think that a large part of you will quickly realize the work that this represents.”

  28. blender 2.80 is a whole new game and that’s what attracted me to blender in the first place and after i found out about it’s open source nature i understood a little bit of the freedom it gives ,especially for inspiring Artists, Hobbysits,Students and even Professionals alike. of course don’t know evey detail about it’s history but as far as i can tell blender and addons devs know what they are doing for years, this is not something new to them ,they know the license better than casual users and know how to make money out of it and surely will continue to do so………plugins,scripts even softwares get shared legally or illegaly and everyone knows the more restrictions you put on it the more people want it, and that’s why most paid ones are all leaked,cracked in just few weeks while open source ones are rarely get these attacks and even in the hackers world they respect open source more than commercial companies…GPL may not serve eveyone but it’s surely does it’s job, the more blender “core” becomes powerful the more it attracts people who want to use it for various reasons including selling addons for living and that’s what it’s happening now, personally i think the quality of your work will put you in a huge advantage instead of the license type……blender is growing and along that it’s community of users and developers, my hope is that we can all work togather for better.
    maybe Blender foundation could make some credit/point system or whatever that rewards addon devs for contributing to blender with patches..etc i feel many small addons could have been integrated directly in the code itself that will gives both addon devs a reward and a sense of accomplishment.
    but probably BF doesn’t have time or resources yet to do it, so i am interested on what you guys think it’s possible to do.

  29. I don’t think this is a issue at all. If people don’t want to pay for an add-on, these people would probably pirate software as well (Blender and/or others). No one with a minimum moral commitment would and should share and use add-ons without paying.
    What license say is irrelevent. I ALWAYS pay for my add-ons.

  30. I am very thankful that Blender is using the GPL. I believe that Blender is much better because of it. Thank you!

  31. Dear Mr. Ton, please update Lipsync importer addon in Blender 2.8 for Papagayo.

    Thank you.
    Firman RL

  32. Ton explained it very well, I see several points here:

    1.- No one is preventing you to sell an addon, even when it must be licensed under GPL, in this case Ton says that you charge for teh download service, I think differently, what you pay for is the continuous development and evolution of the addon and support for it (and for the download service too hehe)
    Make that clear and users will be happy to pay for it.

    2.- If you want to connect any Blender addon with a closed source piece of software, there are ways, like the bridges Ton spoke about, of course anyone is free to clarify or not clarify something, so if you want a proper answer for this the best way is to contact the FSF, they will charge around 900€ (coud be more/ could be less) to solve the inquiry, but you will have the solution coming from the maximum authority (below court) regarding GPL licensing

    3.- Many persons have described here different solution, I also would like some commercial plugins to come to Blender form other platforms, but sincerely I don’t see the actual real need for it, and I’ll explain this:
    – We could want more render engines, but Cycles is flexible enough and completely open source so we could be better hiring more develpers to implement the features we miss, like more AOV’s, other rendering techniques, etc… we CANNOT do that with other engines like Corona, Vray or Arnold, we are left in the developers hands while with Blender and Cycles we can decide the future of it, not just with the love of our hearts, but with the money in our pockets, and while we can fund B.I. in the dev fund, or the Blender Cloud, something I think completely necessary, we can also hire devs on our side to make them work in the specific features we need/want, this goes for any medium/big studio, they can make Blender grow fast, we have MANY features coming from Tangent and Theory, imagine if every studio dedicates part of their dev force to develop Cycles features for production!!!

    – For other things like other types of plugins, for example, Itoo Software’s plugins (which BTW they are not present outside of Max… not Maya, not C4D) there are alternatives, like for example for the time being Animation Nodes, it’s not just for motion graphics, but also for tools development, it give us amazing capabilities, we also have Python addons or scripts, and finally if we need high performance C++ addons there are other options, like Cython or Boost, or programming directly inside Blender!

    And yes, I know that not everyone is a dev-wannabe like myself, or knows anything about the technical world, but hey… what do you do when you purchase a 500€ plugin? or what do you do when you pay 700€/year for a plugin? you pay for the devs, ok… pay for some dev, gather some people that really wants a feature (like a new particle system) talk to a dev that is able to do it, manage to get some funding and pay that dev 700€ in a year (for every person that wants that feature) and you will get the new particle system, look what Tyson Ibelle has done with TyFlow, it was just 1 person in 2 years… 1 person!! So it’s not a big problem to get high quality addons and evolution inside Blender, in fact is MUCH BETTER than in closed source software environments because you don’t depend on any Auto-whatever manager to decide what’s best for you, an egg spline, a tear-off viewport or a full fluid simulation system (TRUE STORY BTW)

    So, for me personally took a while until I understood the Blender and GPL ecosystem, and I was amazed for another thing, the endorsment from the users, yes addons are GPL but in general I’ve never seen a high traffic about sharing paid addons, it’s not piracy, it’s totally legal, but people respects developers and want the development to continue so they pay the developer, and you know why the prices are so much lower than in other ecosystems? because you are actually paying the developer or the development group, not the big company that fagocitates the money to be used in marketing for some new shiny product that should have been a new feature in the product you already have.

    So to wrapt it out:

    1.- You can sell addons

    2.- You can ask for closed source addons and developers can develop closed source addons

    3.- Questions can be clarified out by the FSF lawyers, Ton or the BI don’t have to, in fact they don’t have any power over the interpretation, the FSF is the best way to go IF you really want to, and please make the document public if you want to pay for the clarification (that’s just me asking, you are not forced too do that of course) but…

    4.- …IMHO it will be like shooting in your feet, is much better to develop for a sustained Blender evolution in the future, to hire developers by yourself, to improve Blender between all of us, the paradigm change is that WE have the Blender source code, WE have the power, solo-freelancers, Small studios, medium studios or big studios, the power belong to us, not to someone in a big company, so let’s leverage that power, lets fund Blender, loets hire devs ourselves for our teams or lets involve ourselves in development (the ones who are developers)

    I want things to be clear about closed source software, just because I think it adds a layer of freedom, but I totally endorse GPL, Ton’s opinion and B.I. position about GPL, it’s possible to make business and money with GPL, it’s just a different paradigm, we had an absurd paradigm change with the absurd SaaS rental license systems, well this is another one, the first was against users, this is in favour of users and the software itself, learn how to benefit of GPL in business and do that.

    Busines is legitimatem we all need money to live, to evolve, we need and want to pay for computers, offices, houses, food and many other things, this is just a different way of making money, RedHat discovered it many years ago, the actual value of all this is the actual real service, not the code by itself.

    My 2 cents…

    BTW, totally agree with Dimitri Paiva: “If people don’t want to pay for an add-on, these people would probably pirate software as well (Blender and/or others)”

    P.S.: a good way or platform to find developers to be hired by small teams could be a great addition, I know that there is Blender Network, but you have to pay to be there, something free that charge only a small fee for the job when someone is hired could be better and expand developers/artist visibility, but that’s my opinion, this could be also organized outside of the B.I. frontiers by some users.

  33. A bit off topic, but if developers can only write GPL addons, surely blender be made available to compile under GPL or foss software.
    Currently, the supported way to compile Blender on windows is through visual studio. Visual studio is a decidedly anti-free (as in libre) software, as many of it’s part are behind a paywall and the ones that are not are being a registration and cost the fee of personal information (community edition).
    I hope one day it will be possible to compile it under mingw and the likes again.

  34. I haven’t read through this whole post of comments yet, but can someone briefly explain how you encourage the best developers (or any really) to write add ons or Blender code if people are just free to share it with anyone or if you can’t technically charge for your code? Or to put it another way, why would someone develop for Blender when they can potentially make a more sustainable living writing plugins for Maya, Max or C4D?

    • Simple – counter to what may seem obvious, the best developers trying to make a living off addons for Blender is not that great for Blender as whole.
      Addons do sometimes solve an urgent problem and are great for that. But evolving them into full-blown well developed “applications”:
      1. creates a conflict of interest with eventually developing those features inside Blender.
      2. over time erodes the goal of first time user accessing the full available functionality of Blender at zero cost (as it will get addon dependent eventually).

      As is addons are great at what they do, and as is, their limitation to what can be given away _virtually_ for free and/or forcing them to generate revenue in some other way (promoting/popularizing someone/something) is a good thing in long term.

      There are downsides to everything, including GPL, but in light of those we tend to be blind to it’s upsides.

      • On #1, that’s never been an issue with any other application out there. Sometimes the features of add-ons eventually make their way into the native application, sometimes they don’t. The point is that third parties are there to do what the core developers can’t always address either short term or long term or to do something that the native app does, but only better or more streamlined.

        I don’t know, I think Blender Market gets it right where a small portion of their proceeds feeds the Blender fund. Blender is of course free to download and use however you like, I still see the value in donating montly as well as buying add ons that also may benefit Blenders fundraising goals. If you want Blender to develop these summer of code projects, you donate because it costs money to develop like any other app.

        On that same token, I see the value of allowing there to be a marketplace for third party developers to make a living doing something that fills the needs of the Blender community.
        People can buy or not buy, but there must be some kind of motivation for people to continually develop an add on.
        I’m all on board Tor’s idea of Blender being and remaining free, but I also think its, as someone said above, shooting yourself in the foot at the same time.

        • My point was that while motivation is needed, it shouldn’t become too profitable. For example – Imagine someone making their whole living dependent on a single advanced addon. Would you as a developer rise a hand to include the same functionality into blender, thereby completely destroying someone’s income? And would you as the owner of said addon not do something to prevent that?
          Ans this is not the only potential downside.

    • Why are add-ons different than other Blender features? Are you worried about why anyone would contribute to GPL in general? Do you know how many succesful GPL projects are out there? Start with Linux!

      You can easily see how many contributions happened (and still happen) by volunteers online. And a growing amount of contributors now get paid by companies or studios who need Blender. That’s how a more volunteering based open source project can grow up – get companies on board who take part in the development community.

      • Ton, I’m genuinely curious, are you just thinking of specific cases where add on developers have had success from this process? Are you at the same time ignoring others who have lost(or may yet lose) to this process?
        I saw your post from somewhere else that supporting third party development with development funds is definitely the plan. But how can that be possible if you don’t meet your own development fund goals (like hiring 10 developers for instance).
        I just see it from an outside perspective. Why would someone who may already be making a living using their coding skills to make add ons for other commercial applications (and there are some truly great ones out there) bother with bringing their code which they want to keep the rights and source to, bring their add ons to Blender if the code can just be shared freely? You hire people to code for Blender, why not the same love and respect for add on makers?

        • It’s strange that from an outside perspective the view is “people making a living with coding skills” and not “a community who makes a free and open source project”. The concept of “making a living with software” is not why there’s a Blender project. That’s why there’s a Maya or Houdini. Let’s not mix that up.

          Blender Add-on developers, just like C/C++ developers, are considered to respect Blender’s freedom and license. Every developer enjoys Blender’s free license equally, they don’t have to pay for using it. Even better – developers can count on the Blender Foundation to protect their freedom. That’s the default mode, the bottom line. Making money by respecting that principle is possible, but it takes a bit of empathy and intelligent effort.
          It’s great that add-on developers can make money on the BlenderMarket, but it’s disrespectful to the Blender project when such add-on developers then consider sharing their work as “piracy”, or when they consider contributing code to Blender as something that’s not their responsibility – but something others apparently take care of. It’s quite a selfish disillusion to treat your own Blender code as sacred property, but expect to get all of the other Blender code as Free Software. Freedom goes both ways you know, it’s reciprocal.

          • “The concept of “making a living with software” is not why there’s a Blender project.”

            I’m sorry but you and the devs are making a living with Blender.
            This is weird to see how you separate you and add-ons coders.

            You are paid to make blender, addons devs cannot be paid to make add-ons (crowdfunding doesn’t work for addons on Blender), they must make it first.
            If they give it for free, nobody will give them money, we all know that donations don’t work either.

            So, how an add-on dev can make a living to improve Blender like you do?

          • Heavy3D kind of has a point, at least I agree that it makes sense. You said no one’s code is more important than anyone else’s. But if Blender developers are getting paid to develop Blender and they are earning their living at least for time, why is it that add on developers don’t get that same opportunity? Isn’t their code as important?

  35. Blender would not exist today in its current form had it not been licensed the way it was in 2002.

    The current question about addons is not a new position, it’s a direct consequence of that decision.

    Folks can argue about whether that was the right decision, but you can’t turn back the clock.

  36. I see where Ton is coming from. There are 2 distinct philosophies developing that he feels needs to be brought into alignment with the overriding Blender paradigm of 100% FREE for all. You have 1 group that is donating their time and talent to develop features within Blender and you have another group who wish to use their time and talent to commercialize and monetize developed features within Blender.

    So you have the core group who say its not fair that we spend tireless hours developing features so everyone can benefit without any compensation other than seeing Blender advance. Then you have the plug-in group who say its not fair that we spend tireless hours developing features that can benefit Blender users without receiving adequate compensation and protection for their labor.

    So you have 2 distinct philosophies on how tireless hours spend developing for Blender should be rewarded and they are proceeding in opposite directions. Ton has taking the position that he needs to redirect both groups on the same path.

  37. I think the problem with the “open” movies of the blender foundation, is that they aren’t really open. How can you call something an open source movie when the only way to access the source is through a paid subscription to a download service (e.g. Blender Cloud). How is calling that an “open” movie justified? I remember when Venom’s lab training came out as “open” training resources. And yet the only way to get it was buying the DVD. How is that “open”? I was a younger kid back then without much money. There was a guy on the blenderartists forums who was posting links to the files he had ripped from the DVD; but people were giving him a hard time, because “people should pay to support it.” Well… I’ll tell you what, if the only way to access open source content is through a paywall, its not open.

    Seems to me the same dichotomy is happening with the addons. But I really think the Blender Foundation is just as guilty of this as well. Hiding open content behind a paywall may be technically open source, but I really think it goes against the spirit of open source.

    • Open means that you get the source code, in this case, the source art(as far as I am aware). You can license movies under a GPL like license(see Free Art License). Having people pay for the source code is permissible under GPL, as long as it is GPL without the no monetization part.

      The way that GPL goes around pirates is that it would not be in everyone’s interest to all be working on separate projects as opposed to just the one, be it the main on or whatever.

      “Pirating” open source things are legal under GPL, though it technically isn’t piracy, just sharing.

      Also, it is permissible to take Blender and do nothing to it and sell it for $1000 per download, just no one would profit from it because it is already free.

      However, things made in Blender can be put out with any license you want.


    • The Blender Cloud subscription provides you access to freely licensed data, which you can copy and share (as happens already a lot). The most succesful add-on on BlenderMarket (retopo) is freely available in github too. Playing by the rules doesn’t have to harm you, you just have to do a little bit more your best.

      • Hey Ton, if I read you correctly, in fact, addons provides you access to freely licensed data. So, it’s the same as the Cloud in fact.
        So, why all this fuzz with Add-ons and the GPL?

        • Haa, there is a difference, in fact, people pay only once for addons, not every month.
          Maybe we should make a monthly subscription for add-ons too.
          Actually, Addon’s devs need to improve their tools every day to find new clients.

  38. Ton, I put my opinion in simplest words: without support for commercial/close code addons Blender never will be used widely. Of course Blender is quite popular, used especially in gamedev and small studios but none of the big film studios or archviz will use Blender without support for VRay, Corona, Octane, FlumeFX, Ornatrix, ForestPro etc. With GPL license it’s not possible to have those commercial plugins but with Apache/MIT it is, and changing license from GPL to real free license is hard but possible. Some people say that Blender doesn’t need this or I should use other software. Actually, we should think that Blender can be open and better – with support for commercial addons there’s should be bigger community and bigger funding from new users and companies that would be interested in Blender’s developing.
    I can’t intergrate Blender in my job workflow because I don’t have choice – I can use only Cycles but it’s has flaws (speed, features) in comparision to commercial counterparts like Corona or VRay.

    Here’s two developers opinions:

    “Because entire Blender is covered by GPL licence, it is forbidden to link anything closed-source to it (not just commercial as in “you pay for it”, but anything closed-source, which includes “it is free to use, but I won’t give you my source code”). Making Corona opensource software (OSS) is out of question for me, I need to make it commercial to be able to fund its future development.”

    “Sorry, but the GPL is really a big issue (*). It does not matter if the plugin is bundled or not. What the license forbids is linking a binary compiled from GPL code (here, Blender) with a binary compiled from closed-source code (here, the Substance engine dynamic library) or code released with an incompatible license. This means that it is not legally possible to release a closed source plugin in the form of a compiled dynamic library (.dll, .dylib, .so, depending on your system) for Blender.
    Some companies got around that restriction by releasing an open source GPL “dummy” plugin that only acts as a simple bridge between Blender and an external closed source application which does the real work. As there is no link between the GPL binaries and the closed source binary, this is legal. But this trick cannot be applied in our case because getting back the textures from an external application would be too slow to allow for real time feedback when changing the inputs of a substance (which is the whole point of the integration in the first place. Without it, the integration would not offer much over exporting the bitmaps from Designer).
    (*) or the fact that the Substance engine is closed source is, if you look at it from the FSF’s point of view.”,405.0.html#msg8949

    • I hear these arguments since the beginning. I know that the dominant ecosystem for 3D and CG tools is based on proprietary software business. That, however, is not a reason to then give up on our own (even when smaller and less economically relevant) free and open source ecosystem. Our “open and free domain” has value in itself, and it is worth protecting. That is why I wrote this text, to clearly define what it means to be Free Software, with its benefits and drawbacks. It’s not battle with winners or losers either. It’s just there, it’s growing up and becoming more and more relevant – an unstoppable force. In the past 20 years I’ve seen the market and studios move towards our direction, and all signals are that this is just only the beginning.

      • As I understand you’re for GPL because it’s protecting Blender. But GPL protect Blender from what? Paided forks? It will never be thing as it isn’t a problem right now when everyone can copypaste Blender source code. No one will ever change or “destroy” Blender as Blender will be developed by Blender Foundation. People always will choose only one trusted source.
        From my point of view Blender with GPL a little bit looks like a walled garden – I can’t choose another renderer because developers can’t do software for Blender. My work (product visualization) requires fast and high quality effects that Cycles doesn’t have (for example realistic caustics). And I need production ready, supported, paided engines like Corona or VRay. As a long time user of Blender (more than 10+) I can’t work anymore as market demands better, faster and more complicated effects that Blender can’t achieve in every aspects (like simulations). I know that in this situation I must choose another software – but is this a solution? And how many people would face that as software is more and more specialised and relies on additional plugins?

        1. Why Blender can’t be on Apache/MIT license? Like Cycles? It is possible to change license from GPL (OpenSSL is an example). Blender would stay in his open sourced ecosystem but would be more permissive for addons creators.
        2. Are you consider to do something or make some legal workaround to have a possiblity to make a closed coded addons/plugins for Blender?
        3. Are you consider to make some bigger disscusion with community about the license of Blender or your words are closing this discussion?

        Thank you Ton for answer, really appreciate that some Blender dude can discuss with the Blender creator 🙂

      • Linux became an unstoppable force (on the server and embedded markets) due to its open nature and the willingness of major software/hardware companies investing like trillions of dollars in R&D. But Linux’ uses are not a niche they are ubiquitous. Blender on the other hand has just one very advanced/specialized/skilled niche use – 3D graphics. It will never be ubiquitous (and thus an unstoppable force) as it is not that kind of a product. Also not everyone has a Blender foundation to support their free-for-everyone work. I also see that most of the people who work on Blender are really young and could get away with a low income.

    • Blender could one day dominate the market, which might solve these issues, I believe that its free policy has given it that potential. Blender is practically immortal, development will continue even long after Autodesk and others went bankrupt and have been forgotten. Shared development is much more effective in the long run, if one developer drops out someone else will volunteer to take their place and can reuse existing code.

      • There is a plenty of Software with public domain code that were abandoned long time ago including 3D modelers. Being free does not guarantee you a longevity.

      • Reality is that creating addons on GPL license and selling them is not as profitable for developers as close coded addons. No one at Chaos Group, AfterWorks etc. would open their source code. Because of GPL Blender users will NEVER receive high quality, faster and essential tools for work on most demanding tasks.

        And actually no one could answer to my question about Apache/MIT – this simple but hard change could resolve and ended biggest issue with Blender – GPL that is blocking software and throwing into walled garden.

        And I will wrote this in most simple form as it possible:

        GPL = open source, Blender only with GPL addons, used only in limited way (by hobbist, gamedev).
        Apache = open source, Blender can has GPL addons, close coded addons that opens possibility for biggest studios who could help develop Blender because of it’s open sourced nature.

        Why are you against Apache?

  39. Blender’s free policy has allowed it to become something far greater than many things out there.

    I like to compare Blender to a good friend. Can you buy friends? Wouldn’t paid friends be of better quality? To me the answer is no. Blender lets those that enjoy it maximize their creative experience, without strings attached. Much like your best friend won’t charge you a fee each time you hang out.

    Imagine your village or town decides to make a giant snowman, everyone gets to join in the effort irrespective of their financial or personal strengths and is given the freedom to express their creativity in the task. That’s the value Blender gives us.
    Wouldn’t it be inappropriate if a group of people started complaining that the snowman would have been of superior quality and built faster if only the villagers had gotten paid, if we had sent all the inexperienced people home letting only the experts do the task? And while we are at it, nobody should be allowed to see how they do it, send away all bystanders!

    I’m a person who heavily dislikes running anyone’s junk on my CPU unless I am free to inspect and modify it as I see fit. Projects like Blender drop the curtains, stop treating us like ignorant children, ripping us off behind the scenes and acting like their abilities are greater than they are.

    Proprietary software is not for you, it is only for the owner.
    It has measures installed to prevent piracy but that also steal my CPU time, wasting energy and emitting CO2 (almost like ads!). I say no to that. Many proprietary tools/applications heavily exploit free workers: the countless of forums where users help each other troubleshoot issues. When are they getting paid for playing into the owner’s pockets? Let’s put a donate button under every post and ask 3d Max for support.

    If you think that you are the only one who could make this great plugin you made, you are wrong. Anyone can do it, much like anyone can learn to make a snowman. The only thing that sets you apart is your willingness to do it. In that sense, if you won’t make a plugin because you feel like your financial situation doesn’t allow it, don’t worry, someone else will do it eventually. Why not share your ideas to speed up the process? If you feel like you own the idea, then find another snowman to build.

    If a plugin isn’t maintained by the original maker but it is highly requested then naturally someone else will continue it.

    Ton and whoever else was involved made an excellent choice. They decided that the user is part of the family.

  40. Thanks Ton, for what you, and everyone else, who develops code to make Blender the great platform it has become (and will be in the future).

    I can appreciate how developers feel about not wanting their code (and invested time), squandered through people simply sharing add-ons after an initial purchase.

    Worse would be people to take the code, repackage it into something else and then try to resell that hurting the original developers.

    However I agree with the tone of what Ton has expressed; Blender is FREE, don’t try to commercialize it in some form or fashion just to “protect” a plug-in you have developed.

    I refuse to purchase any plugin that offers up some kind of “phone home” features for license checking, along with any other commercial like lock-down schemes.

    That being said, add-ons like HardOps, KitOps, DECALMachine, Fluent, Asset Manager, and others that I have purchased, too numerous for me to list here, represent some of the BEST tools and feature additions for Blender – which proves how great the Blender platform is for developers, and what can be done with Blender when add-ons of this caliber are used with Blender.

    When I see new wares from these (“my favorite”) developers, I immediately try to support them to show my appreciation for their work, talent and time invested – their tools make me a better artist on a daily basis, I’d be a fool not to invest to keep them going!

    That said, all I would have to hear from any of these developers is “XYZ has taken my code and is now trying to resell…”

    I would IMMEDIATELY put that developer on my “BAN” list, and voice as loudly across the forums I inhabit my distaste for what that developer is attempting to do!

    So I can say to all add-on developers here, I will not only support your work, I will also DEFEND your work in anyway I can to offset the GPL license issues as voiced here.

    If others were to do similar, (and I’m sure many would), I’d hope and believe that developers will continue to see the Blender platform as a great environment for developing code while also receiving rewarding compensation for their time and efforts.


  41. I for one prefer to stick to what Blender offers out of the box rather than addons. There’s no guarantee that the addon I invested money in and time to learn it and how it fits my personal workflow will be further developed and refined. The dev might consider the revenue didn’t live up to their expectations and just phase out the development (guess what they don’t even bother to announce they did). I’m better off supporting the dev fund rather than an addon dev whom I know nothing about and whether he’s fully committed to the project he’s developing. For the most part they don’t even care to give a trial version so that I could try before buy – why the heck do I have to buy a pig in a poke? And please don’t tell me I should refer to youtube videos and well known blender artists’ testimonials – devs, has that ever worked?

    • From what I’ve seen over the years, paid add-ons are more likely to get updated and maintained, because the developer has a reason to do so – no one will buy a broken add-on.

      Free add-ons will only be maintained for as long as the developer him/herself is still using it, or still care enough about it to keep it alive after someone tells them it’s broken.

      > they don’t even care to give a trial version so that I could try before buy

      This is usually because Blender add-ons are all open source, meaning someone could very easily remove the code in the trial version that makes it a trial and just keep using it forever. They could also then publish this code online for others who don’t know how to do the same.

      For what it’s worth, I sell an add-on on the blender market which has a free trial with no time limit, and the full source is all on github anyway.

  42. On the one hand, there are no bad greedy developers and good contributors.

    The reality is in between, most commercial addon developers are also contributors, either directly through the development fund or through contributions to the code. These additions also contribute to Blender’s success by adding significant value for users.

    The developer’s freedom should also include choosing the best method to ensure adequate funding for his project. The Blender Foundation has chosen to finance itself through donations, the addon developers use a more direct model – sponsorship remains difficult to obtain and donations are largely insufficient.
    But in the end we have a common goal, to improve Blender’s ecosystem, and the same means, money.

    I think this discussion is damaging to Blender, and the real question should be how to work together to move forward with this wonderful program.

    If your position is to make all developments free of charge, even if it means waiting until it is financially possible, then it is your responsibility to assume your choices by clearly opposing the business model made available to addon developers by the blendermarket, and to do without their (small) contribution.

  43. GPL does not prohibit selling. The developer just needs to provide source code on request.

  44. Wouldn’t it make sense if paid close source add-ons pay royalties to the Blender foundation? So add-on authors could protect their software IP and also fund the core Blender development?

  45. i think blender devs have this “open source” ideology that they want to enforce it on everyone else
    u need a whole ecosystem that trives from that but comparing it to commercial ones ,it is day and night, millions of dollars are poured every year in those projects while open source barley gets fraction of it since it’s freely redistributed, so lets be realistic here blender is out of the circle and it’s interoperability with other commercial softwares or pulgins is almost none which makes it hard for professional Artists and Studios to use it as their main 3d package unless they are willing to jump off the license restrictions and do it by themselves and break the rules……blender was never meant to be part of the big commercialized industry but rather to serve the small and rather lonely community, i think anyone who came to use blender understands that, including addon devs which probably don’t make much by just selling addons ,same happened with those who used blender game engine…it’s good as a startup for newcomers to learn 3d and get their hands dirty but i wouldn’t recommand it to someone who wants to make it in the big industry.

  46. Ugh. I’m very late to the conversation.

    A lot of people are saying “I’m not a lawyer, but…”. I actually am a lawyer, and I spend a lot of my time negotiating IP licence agreements. The open source debate is as old as time. I could fill pages on the legal aspects of the subject, but I won’t because: (a) most people would find it very boring; and (b) my personal viewpoint is already represented well in other comments above. There is little point in me adding to that aspect of the debate at this point. What I will say, however, is that copyright and proprietary code is an important concept for society, and not automatically “evil” as I think people in the Blender community sometimes imply.

    I am also a Blender add-on developer, and I sell that add-on for modest amounts. I know full well that people can take that code and share it with others. I actually draw that to customers’ attention on occasion.

    Where I agree with Ton:
    I agree that when you pay for a Blender add-on, you are really paying for knowing someone is there to support it. I’d go further and say that you are mostly paying to encourage the person behind it to maintain it and develop it further. This is why having to release my add-ons subject to GPL doesn’t really bother me.

    Where I disagree with Ton:
    When he says that we should be *encouraging* people to freely share add-on code. I personally think that is bad taste. I think we should be *permitting* people to share add-ons freely, but we should be *encouraging* people to pay for paid add-ons if they like them, find them useful and want to encourage further development. This will lead to a more healthy community, and less of the sense of entitlement that some in the Blender community currently seem to display.

    Now, I’m not relying on my add-on development to make a living, so you might say it is “greedy” for me to sell my add-on. If you think that then OK, you are entitled to that opinion, but I would point out that I spend a considerable amount of my free time developing the add-on, making it better and also responding to support requests. Some of these are legitimate concerns with the add-on (which I fix promptly), but a lot are just people with minimal experience of Blender struggling to do basic things. I don’t mind giving that kind of support, but the bottom line is that I probably wouldn’t do it if I wasn’t making a (pretty small) amount of money from it. I work hard and my free time is valuable. I’m also not forcing anyone to pay for my add-on.

    That for me, however, is a totally separate issue from me being required to release by add-on under the GPL licence.

    The bit that made me laugh out loud at my computer monitor was when Ton says “what an incredible API these C developers made for Blender!”. Honestly? I love Blender, and respect the developers, but lets call a spade a spade – the Blender API is *awful*, and the documentation is so sparse that it borders on non-existent. Developing a Blender add-on not only means frequent posts to StackExchange the the developer forums asking for help, but also hours of trial and error as you try to guess what some cryptic or incomplete API documentation actually means. It’s fumbling around in the dark. My add-on is pretty basic compared to some out there. The fact that people can make the sophisticated add-ons they do for Blender absolutely floors me, as I know first hand what they are being given to work with. Sorry if that sounds harsh, but it’s how I feel based on my experience.

    • If one wants to use closed source libraries (like third party libraries) it won’t be possible with the current license I guess. Is that so? Which means – no big third party commercial extensions.

      • The GPL licence requires “derivative works” (remember that term!) to be under the same licence. When you are writing an add-on, literally the first line of Python that you write is “import bpy” – which means you are importing into your own code the API libraries that the Blender developers have written. That action makes your add-on a derivative work of the Blender code, and therefore it must be licensed under the GPL licence.

        Now, you definitely *can* write an add-on that interfaces with a close source program or libraries. A good example might be a third party, closed source render engine. Assuming the render engine was totally stand-alone, you *wouldn’t* have to make the render engine itself subject to GPL (as the render enginge itself is standalone and not a derivative of the Blender code), but you *would* have to make your Blender add-on that interfaces with it GPL.

        A good example is OctaneRender, which I think illustrates this concept. Their actual render engine is closed source, and it works with multiple different 3D software packages. For Blender, they make available a custom built version of Blender that integrates with OctaneRender. The custom version of Blender is open source (GPL, because it has to be), but it interfaces with closed source OctaneRender also running on your machine. They will have done it this way to avoid any suggestion that their closed source render engine is caught by the GPL licence, which they *really* won’t want! If (for example) they had gone further, and fully coded their render engine into Blender, it would have becomme a derivative work (as it derives from the Blender code) and they would have to make it open source under GPL. That’s the last thing they want!

        So yes, big third party commercial software providers can build Blender interfaces to their closed source stuff, as long as they are a bit careful. Only the code that relies on the Blender code will need to be GPL.

        Usual disclaimer – not legal advice etc.

    • Seems like this forum doesn’t let me leave a like so, please, accept this: positive feedback*

  47. Thank you so much Ton for this article ! i was worry about the direction of blender, allowing people to sell more and more the addons, adding limit to the users class… richs will have access to some features and poors not.. wich is the inverse process that we followed from the beginning !

    I am so happy that everything become clear again, Open source and free software is a major power for creativity, it cannot be limited, due to some people who want to earn money on top of it… Sharing is always the solution… with love.

  48. Ton’s encouraging users to share paid addons who their devs spent weeks ,months and some even take years to fully polish then call it “act of love” is very disrespectful…most blender channels including marketing website like blender market and addon developers give back to blender funds and retopoflow example is not an ideal one since their devs have cgcookie to fall on to…..if all this stops then there will be no donations no support for future blender and the developers working on it won’t make a living by doint it for free…u got put yourself in people’s shoes especially GPL doesn’t prohibit you from selling addons….this whole conversation shouldn’t have been brought up in the first place.

  49. A lot of people is concerned about the possibility a customer of an addon has to distribute it for free… But doing so is optional.
    At the end is the user (and buyer, in this case) the one responsible of the potential damage to the financial situation of the developer. No developer is forced to work on a specific addon, they do it by their choice and that is amazing.

    What I really want to point here is that WE, users, are the weak point of every license agreement. I grew up in a Country where almost every artist is using pirate versions of licensed software and the industry, and society itself, is fine with that… And there is a good reason for that, here 2.000 US dollars are a lot of money and it’s too difficult to invest that much once per year.

    On the other hand there is open source software, and it carries the possibility of using completely legal software in a small studio. No customer here ask what did we use to get the job done, we are just proud of using “clean tools”.

    With that said, everything you are worried about is your own conscience.
    Yes, a lot of people will continue to distribute software for free (no matter the license), but it doesn’t mean it is worthless to work on these.

    At this point we should be concerned about the morals of giving up for free something that someone worked on and someone paid for… And no legal agreement will ever fix that.

  50. The suggestion to spend time and energy on code-adjacent activities (which require different skills) require works a lot better for an organization balancing the contributions of multiple paid employees than it does for an individual who may have other committments already. If you can market and sell training videos why not just do that instead of also coding, as an individual?

  51. Thank!
    Excellent article, just looking for information on this topic.

  52. Really glad for this article.
    I have these extra problems with some add-ons that are being sold:
    – first, it seems nobody ‘dares’ to implement similar functionality from some successful add-ons directly into blender.
    – nobody dares to take a GPL addon, and submit it for distribution in Blender, even if it has functionality that everybody needs.
    – some addons are distributed as binaries.
    I think this creates a paradox situation. On one side, cash-flow enables great addons. On the other side, it hinders some of the essential advantages of GPL, even if not through the license, but through some non-written pseudo-solidarity rules. These advantages are possibility to use other people’s code at any time, and possibility to cooperate on something or improve it also without consent of the original author(who agreed to this through the license in the very moment when he started scripting addon for blender)

    b.t.w. I sell add-ons for a long time. All my addons are either on github or in blender source tree.

  53. if one has a server running a modified blender, and charge others to use it, it’s not violating GPL because the exe was never distributed no?


    like Stadia?

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