End User Licence Agreement

Licence to use MDSyntax

This EULA covers the software itself — what you may do with the copy on your machine. It sits alongside the Terms of Service, which cover purchasing.

Effective 2 August 2026 · Version 1.0 · Licensor: Mentis Vision LLC

Store note. If you obtained MDSyntax from the Mac App Store or the Microsoft Store, the licence terms of that store apply to your copy. Where a store's standard licence terms conflict with this EULA, the store's terms prevail for that copy, and Apple or Microsoft — not Mentis Vision — is responsible for the obligations that store's terms assign to them.

1. Grant of licence

Mentis Vision LLC grants you a personal, non-exclusive, non-transferable, revocable licence to install and use MDSyntax on computers you own or control, subject to this agreement. The free tier may be used indefinitely on any number of your own machines. A Pro licence key may be activated on up to three machines at a time.

2. Permitted use

  • Use MDSyntax for personal, academic, internal business and commercial work.
  • Produce documents with it and use, publish or sell those documents freely — output is yours, with no attribution required.
  • Make a reasonable number of backup copies of the installer.
  • Move an activation between your machines by deactivating one first.

3. Restrictions

You may not:

  • Rent, lease, lend, sublicense, resell or host MDSyntax as a service to third parties.
  • Reverse-engineer, decompile or disassemble the software, except to the extent that applicable law expressly permits it despite this restriction — including for interoperability under Art. 6 of the EU Software Directive.
  • Remove or alter any proprietary notice, or attempt to defeat licence enforcement.
  • Distribute a modified or repackaged build under the MDSyntax name or mark.
  • Use the software in violation of applicable export control or sanctions law.

4. Ownership

MDSyntax is licensed, not sold. Mentis Vision LLC and its licensors retain all right, title and interest in the software, including all intellectual property rights. This agreement grants you no rights in the MDSyntax or Mentis Vision names, logos or trade dress.

5. Your documents

You retain all rights in every file you open, edit or export. Mentis Vision claims no interest in your content and does not receive it. See the Privacy Policy for what the application does and does not transmit.

6. Open-source components

MDSyntax includes third-party open-source software, each component governed by its own licence — among them Electron, React, markdown-it, CodeMirror, highlight.js, DOMPurify, KaTeX, Mermaid and Graphviz. Nothing in this EULA limits the rights those licences give you in those components. The complete notices and licence texts are included with the application.

7. Updates

Updates we make available are covered by this agreement unless they ship with their own terms. A Pro licence includes updates within the same major version at no cost. We may, but are not obliged to, provide support or updates for any particular version.

8. Term and termination

This licence runs until terminated. It terminates automatically if you materially breach it. On termination you must stop using MDSyntax and remove all copies. Documents you already produced remain entirely yours.

9. Disclaimer of warranties

The software is provided “as is” without warranty of any kind. To the maximum extent permitted by law, Mentis Vision disclaims all implied warranties, including merchantability, fitness for a particular purpose and non-infringement. You bear the entire risk as to the quality and performance of the software.

MDSyntax is a document reader and converter, not a system of record. Do not rely on it as your only copy of anything. Nothing here affects a consumer's non-excludable statutory rights.

10. Limitation of liability

To the maximum extent permitted by law, Mentis Vision's total liability arising out of this agreement is limited to the amount you paid for the licence, or US$50 if you paid nothing. Mentis Vision is not liable for lost data, lost profits, or any indirect or consequential loss.

11. U.S. Government end users

MDSyntax is “commercial computer software” as defined in FAR 2.101. Use, duplication or disclosure by the U.S. Government is subject to the restrictions in FAR 12.212 and DFARS 227.7202, as applicable.

12. Governing law

This agreement is governed by the laws of the State of Hawaii, United States, without regard to its conflict-of-laws rules. If any provision is unenforceable, the remainder stays in effect.

13. Contact

Mentis Vision LLC, Honolulu, Hawaii, United States —[email protected].