Agreement
ThreeStrands is a desktop email client published by OpenArc LLC (“OpenArc”, “we”, “us”), a Pennsylvania limited liability company. These Terms of Service (“Terms”) apply to your use of the ThreeStrands application (the “App”) and this website (together, the “Services”). By downloading, installing, or using the Services, you agree to these Terms. If you do not agree, do not use the Services.
You must be at least 13 years old, and old enough to form a binding agreement where you live. If you use the Services for an organization, you agree to these Terms on its behalf and confirm that you have authority to do so. Our Privacy Policy explains how the App handles data.
License and Ownership
ThreeStrands is source available under the PolyForm Perimeter License 1.0.1. The App, its source code, design, and documentation, and this website are owned by OpenArc LLC and protected by copyright and other intellectual property laws. Copyright © 2026 OpenArc LLC. All rights reserved.
The App and the project source code and documentation are licensed under the PolyForm Perimeter License 1.0.1. You can inspect, build, use, and modify the software for permitted purposes, including personal and internal business use. Copying and redistribution are allowed subject to the license's conditions, including keeping the license and required notices.
The license prohibits providing others with a competing product built from this software, even if that product is free. OpenArc may offer separate licenses for uses outside these terms. Third-party dependencies remain subject to their own licenses.
This section summarizes the software license; its full text controls. These Terms do not narrow permissions granted by the software license. If there is a conflict concerning those permissions or their termination, the PolyForm Perimeter License controls.
All rights not expressly granted to you are reserved by OpenArc.
Third-Party Services
The App works by connecting your computer to services you choose, such as Gmail, IMAP/SMTP servers, and Google Calendar, an AI provider, and storage for encrypted sync. Those services are not operated by OpenArc. Your use of them is governed by your agreements with their providers, and you are responsible for complying with their terms and paying any charges they bill you, including AI usage fees.
We are not responsible for the availability, accuracy, security, or actions of third-party services, or for changes they make that affect the App. ThreeStrands is not affiliated with or endorsed by Google or any AI or storage provider.
Your Responsibilities
You agree not to use the Services to:
- Send spam, phishing, or other unsolicited bulk messages.
- Break the law, or infringe or violate anyone's rights, including privacy and intellectual property rights.
- Access accounts or data you are not authorized to access.
- Distribute malware, or interfere with or disrupt any service the App connects to.
- Misrepresent your identity or affiliation, or impersonate ThreeStrands or OpenArc.
You are responsible for the security of your computer, your accounts and credentials, your sync recovery phrase, and your export passwords. We cannot recover a lost recovery phrase or export password. You are also responsible for keeping backups of anything important to you.
Your Content
Your mail, contacts, tasks, and other content remain yours. The App processes your content on your computer to provide its features, and OpenArc does not receive it or claim any rights in it. You are solely responsible for the content you send, store, or share, including what you choose to send to a third-party AI provider.
AI Features
Optional AI features generate summaries, drafts, suggestions, and answers using the provider you configure. AI output can be inaccurate, incomplete, or inappropriate. Review it before you rely on it, send it, or apply it. The App is designed so that you approve tasks, events, contact changes, and drafts, and you are responsible for what you approve and send. AI output is not professional, legal, financial, or medical advice.
Early Release
ThreeStrands is early-release software, and features labeled beta are still in development. Software at this stage can contain bugs that cause errors, sync conflicts, or data loss. We may change, suspend, or discontinue any feature or version of the Services at any time, without notice. We have no obligation to provide updates, maintenance, or support.
Feedback
If you send us ideas, suggestions, or bug reports, you allow us to use them for any purpose without restriction or compensation to you, and you agree that we own any improvements we make from them.
Trademarks
The ThreeStrands name, logo, and related marks belong to OpenArc LLC. These Terms do not grant you any right to use them without our prior written permission. Other names and marks belong to their owners.
No Warranty
The Services are provided “as is” and “as available”, without warranties of any kind, whether express, implied, or statutory, including warranties of merchantability, fitness for a particular purpose, title, non-infringement, and any warranties arising from course of dealing or usage of trade. OpenArc does not warrant that the Services will be uninterrupted, secure, or error-free, that defects will be corrected, or that mail, data, or messages will be delivered, synced, stored, or preserved without loss.
Limitation of Liability
To the fullest extent permitted by law, OpenArc and its members, managers, employees, contributors, and agents will not be liable for any indirect, incidental, special, consequential, exemplary, or punitive damages, or for any loss of data, mail, profits, revenue, goodwill, or business opportunity, arising from or related to the Services or these Terms, however caused and under any theory of liability, even if advised of the possibility of such damages.
Our total liability for all claims arising from or related to the Services or these Terms will not exceed the greater of the amount you paid OpenArc for the Services in the twelve months before the claim arose, or fifty U.S. dollars (US$50).
Some jurisdictions do not allow certain warranty exclusions or liability limits, so some of the above may not apply to you. In that case, our liability is limited to the smallest extent the law allows.
Indemnification
You agree to defend, indemnify, and hold harmless OpenArc and its members, managers, employees, contributors, and agents from any claims, damages, losses, and expenses, including reasonable legal fees, arising from your content, your use or misuse of the Services, your violation of these Terms, or your violation of any law or third party's rights.
Termination
You may stop using the Services at any time by uninstalling the App. These Terms end automatically if you breach them. Termination of these Terms does not itself terminate your rights under the PolyForm Perimeter License; termination of those rights is governed by that license, including its provisions for correcting violations. The sections on license and ownership, your content, feedback, trademarks, no warranty, limitation of liability, indemnification, governing law, and general terms survive termination.
Governing Law
These Terms are governed by the laws of the Commonwealth of Pennsylvania and applicable U.S. federal law, without regard to conflict-of-law rules. Any dispute arising from these Terms or the Services will be resolved exclusively in the state or federal courts located in Pennsylvania, and you and OpenArc consent to their personal jurisdiction and venue. You must comply with all applicable export control and sanctions laws when you download or use the App.
General Terms
We may update these Terms from time to time. When we do, we will post the new version on this page and update its effective date. If you continue to use the Services after a change takes effect, you accept the updated Terms.
Updates to these Terms do not change permissions already granted under the software license.
These Terms, together with the Privacy Policy and the PolyForm Perimeter License, are the entire agreement between you and OpenArc about the Services. If any provision is found unenforceable, the rest remain in effect. Our failure to enforce a provision is not a waiver. You may not assign these Terms without our consent; we may assign them in connection with a merger, acquisition, or sale of assets.
Contact
Questions about these Terms? Open an issue on GitHub or reach OpenArc LLC through the project repository.