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The Yarn Spinner Public License

The Yarn Spinner Public License (YSPL) is a new license developed by us for trial in some of our new product releases. It shares many of the same permissive, free, open source conditions as the MIT License our existing tools are licensed under, but with two key areas of difference:<br>Using our code to train generative AI models.<br>Repackaging our code into a competing commercial dialogue tool.<br>On this page, you can find answers to key questions:<br>Why the change to YSPL?<br>What is allowed in YSPL?<br>What can I do and not do with AI in YSPL?<br>What can I do and not do with competing tools in YSPL?<br>Can I get this code under a different license?<br>Are you still open source?<br>The Explanation is not the License What follows is a plain-language summary of the conditions of the YSPL license, to avoid confusion and also to explain the reasoning behind the listed restrictions. However, this is not the license. And it is the terms in the license that define the rules. Please do read it if you intend to redistribute our code.

View the License<br>Yarn Spinner Public Licence (YSPL) v1.0<br>Yarn Spinner Public Licence (YSPL) - Version 1.0<br>Copyright &copy; Yarn Spinner Pty. Ltd. All rights reserved.<br>Quick Summary<br>This summary is provided for convenience only and has no legal effect. The binding terms are set out below. In the event of any conflict between this summary and the operative terms, the operative terms prevail.<br>Yarn Spinner is free to use for most people and most projects.<br>Making a game or app? Free. Ship it. Sell it. We're cheering for you.<br>Learning, teaching, or making tutorials? Absolutely free. Go for it.<br>Using a contractor or porting house? That's fine. They just need to follow the same rules you do.<br>Working under a console NDA or platform agreement? No worries. Those agreements can add restrictions on top of this Licence, but they can't override what this Licence prohibits.<br>Want to redistribute Yarn Spinner on its own? You can't redistribute the unmodified source. But you can publish a fork with genuine modifications. It must be free, under this same licence, and made to scratch your own itch rather than to set up a rival product.<br>Want to make your own dialogue tool using our code? Sorry, no — unless it's an internal tool for your own studio or university, that you're not distributing, or a public fork that meets the conditions above.<br>Want to feed our code to an AI training system? Also no. You can use AI tools to help you build your game, but you must do your best to make sure those tools do not send our source code back for training purposes.<br>Need different terms? Commercial licences are available, and we can offer other terms upon request.<br>You should credit us alongside your other tools (engine, middleware, etc.)<br>We would love to hear about what you are making! This is not a condition of the Licence, but if you would like to share your project with us or have any questions about this license or our software, please reach out to us at https://yarnspinner.dev or on social media.<br>If your project has the budget to do so, please consider purchasing a commercial licence. It is not required under this Licence, but it helps us keep developing and supporting Yarn Spinner for everyone.<br>That's it. Now go make something amazing.<br>Operative Terms<br>1. Definitions<br>"Software" means the specific Yarn Spinner software, including all source code, object code, documentation, and associated files made available under this Licence.<br>"Licence" means the Yarn Spinner Public Licence as set out in this document.<br>"Licensor" means Yarn Spinner Pty. Ltd., a company registered in Tasmania, Australia.<br>"You" (or "Your" ) means the individual or Legal Entity exercising permissions granted by this Licence.<br>"Legal Entity" means the union of the acting entity and all other entities that control, are controlled by, or are under common control with that entity. For the purposes of this definition, "control" means (i) the power, direct or indirect, to cause the direction or management of such entity, whether by contract or otherwise, or (ii) ownership of fifty per cent (50%) or more of the outstanding shares, or (iii) beneficial ownership of such entity.<br>"Contractor" means any third party, including any contractor, freelancer, or porting service provider, engaged by You to perform work on Your Licensed Product on Your behalf.<br>"Competing Product" means a software tool, plugin, asset pack, library, framework, or service whose primary purpose is enabling third parties to create one or more of the following:<br>(a) branching dialogue or conversation systems; (b) non-linear or interactive narrative systems; (c) narrative scripting tools or editors; (d) dialogue tree or conversation editors; (e) interactive fiction, visual novel, or text adventure authoring tools; (f) a compiler, runtime, or interpreter for the...