Terms of service.

By using the Line9 service you agree to these terms, to the relevant end-user licence agreement, and to the privacy policy. If you are accepting on behalf of an organisation, you confirm that you have authority to bind that organisation.

You may create an account using GitHub OAuth or a magic-link email. You are responsible for the access credentials associated with your account, including any CLI credentials you authorise. You may revoke individual devices and machines at any time from /app/account.

You may not share a seat between multiple people. Each named user requires their own seat. You may reassign a seat to a different person, but seats may not be used concurrently by more than one human.

You retain ownership of every diagram, label, source file, and other content you create. You grant Line9 a limited licence to host, transmit, render, and serve published diagrams to the audience you have configured (public link, private workspace, embed). Anything you do not explicitly publish is never copied off your machine by the service.

You are responsible for ensuring that the content you upload or publish does not infringe third-party rights, violate applicable law, or violate the acceptable use rules in §4.

You agree not to use the service to:

• Render or publish content that is unlawful, defamatory, or infringes third-party rights.
• Reverse engineer the service, except where applicable law expressly allows it.
• Overload, scrape, or otherwise abuse the service in a way that degrades it for other users, or evade published rate limits.
• Embed the Line9 engine in a third-party product without a separate written agreement.
• Use the personal-use CLI commercially beyond the evaluation window the EULA grants.

Rate limiting is enforced on authentication, billing, CLI licence checks, and publish endpoints. Persistent abuse may result in suspension of the affected credential or account.

Pro subscriptions are billed monthly or annually in advance via Stripe. Stripe Tax computes and collects applicable sales tax, VAT, or GST based on the billing address you provide. Adding seats is prorated; reducing seats is scheduled to the next renewal and credited per the rules surfaced in the billing portal. You may cancel from the portal at any time; cancellation takes effect at the end of the current paid period.

If a payment fails, the subscription enters a dunning state and the service may be limited until the payment method is updated. Persistent non-payment leads to subscription cancellation per the billing terms shown at checkout.

You may close your account at any time from /app/account. We may suspend or terminate access to the service if you breach these terms, abuse the service, or use it for unlawful purposes. We will give reasonable notice where doing so does not create a security or legal risk.

On account deletion, your personal data is anonymised per the privacy policy. Audit and billing records are retained for compliance, pointing at a tombstone rather than your name and email.

The service is provided "as is" and "as available". To the maximum extent permitted by law, Line9 disclaims all implied warranties, including merchantability, fitness for a particular purpose, and non-infringement, except where such warranties cannot be disclaimed under the law of your jurisdiction. Line9 does not warrant that the service will be uninterrupted or error-free.

To the maximum extent permitted by law, Line9's aggregate liability arising out of or relating to your use of the service is limited to the greater of (a) the amounts you have paid in the twelve months preceding the event giving rise to the claim, or (b) one hundred US dollars. Line9 is not liable for indirect, incidental, consequential, special, or punitive damages.

When we change these terms, the last updated date at the top of the page changes too. Material changes will be announced via email to the billing-primary address on file at least thirty days before they take effect. Continued use of the service after the effective date constitutes acceptance.

For questions about these terms, write to legal@line9.ai. For privacy questions, see the privacy policy.