Permitted Use
Truncus is for transactional email: messages a person or system triggers through their own relationship with your product, such as account activation, password resets, receipts, invoices, alerts and notifications. Cold outreach, prospecting, purchased or rented lists, and marketing campaigns are not permitted. New sending domains are reviewed before they can send; this usually takes up to one working day.
Transactional email
Permitted transactional use cases include:
- Order confirmations and purchase receipts
- Password resets and account security notifications
- Account activity alerts and system notifications
- Invoices and billing confirmations
- Shipping and delivery notifications
- User-triggered workflow notifications (e.g., “your export is ready”)
Transactional emails must be sent to recipients who provided their email address directly to you and have an existing relationship with your service.
Prohibited Use — Zero Tolerance
The following result in immediate account suspension without warning or refund:
- Spam or unsolicited bulk email of any kind
- Bulk unsolicited marketing, newsletters, or promotional broadcasts
- Purchased, rented, traded or shared email lists
- Phishing, spoofing, or impersonation of any entity
- Malware, ransomware, or malicious content
- Email to addresses guessed from naming patterns, or to addresses the organisation has not published for contact
- Circumventing unsubscribe mechanisms
- Using Truncus to relay email on behalf of unlicensed third parties
- Content that is illegal under Dutch law, EU law, or the law of the recipient's jurisdiction
- Content that promotes violence, terrorism, hate, or child sexual abuse material
- Weapons, explosives, or controlled and illegal substances
These categories are also prohibited by the upstream providers that carry Truncus mail (Amazon SES, Scaleway TEM). Sending them puts the shared infrastructure — and every other Truncus customer — at risk, so there is no approval path for them.
Restricted Categories — Prior Approval Required
The following categories are not banned outright, but they carry structurally high complaint rates and elevated regulatory and reputational risk. Because Truncus sends over shared infrastructure, one such sender's complaints degrade deliverability for everyone. Sending from these categories requires our prior written approval. Accounts that send from them without approval may be held or suspended at our discretion:
- Gambling, betting, casinos, lotteries, sweepstakes, and related “game guide” content
- Adult or sexually explicit content, and dating services
- Cryptocurrency, digital-asset, token, and ICO promotion
- High-risk financial services: payday loans, debt relief, credit repair
- Prescription pharmaceuticals, supplements, and nutraceuticals
- Multi-level marketing, get-rich-quick, and work-from-home offers
- Affiliate marketing or programmatic-SEO content networks with no direct relationship to the recipient
To request approval, email info@truncus.co before you begin sending. Sending from a restricted category without approval may result in the account being held or suspended. Truncus is the sole arbiter of category classification and approval.
Review Triggers
The following limits and patterns are enforced automatically or trigger review, as described in each item. Repeated or serious breaches may result in throttling or suspension:
- Circuit breaker: sending from a domain is stopped when, over the last 6 hours and with at least 50 sends, its bounce rate reaches 2.0% or its complaint rate reaches 0.07%.
- Automatic pause: a domain is paused when, over the last 7 days and with at least 50 sends, its bounce rate exceeds 3% or its complaint rate exceeds 0.1%.
- New accounts: during an account's first 7 days, a domain with at least 10 but fewer than 50 sends is paused and placed on hold if its bounce rate exceeds 25%.
- Only permanent and undetermined bounces count toward these rates; temporary (soft) bounces do not.
- Volume spike exceeding 10× your normal daily baseline
- Sending to role addresses at scale (info@, admin@, support@, etc.)
- High rate of “user unknown” or “mailbox full” bounces
- Recipient-list patterns characteristic of purchased or rented lists — for example alphabetically-iterated recipient sweeps — are detected automatically and, for new accounts, result in an immediate automated hold and account closure. Broad recipient-domain fan-out from a new account is flagged for human review; on its own it does not trigger a hold. A low bounce rate does not make a purchased list acceptable.
Automated systems act first. Human review follows. This order is intentional — reputational damage to shared infrastructure happens faster than any manual process can respond.
Your Responsibilities
- Maintain suppression lists: remove hard bounces immediately, soft bounces after 3 failures
- Honor unsubscribe requests within 10 business days
- Ensure you have a legal basis (consent or legitimate interest) to email each recipient
- Keep sending volume within your plan limits
- Secure your API keys — you are responsible for all activity under your account
- Comply with CAN-SPAM, GDPR, and all applicable email regulations in your jurisdiction
Enforcement
- Monitoring runs continuously. Threshold breaches trigger automated action.
- Suspension is applied first; review follows. This is not reversible once a zero-tolerance violation is confirmed.
- Appeals for non-zero-tolerance suspensions: email info@truncus.co within 14 days of suspension.
- Automated closures, including closures under the recipient-list pattern rule, can be contested once by replying to the closure notice or writing to info@truncus.co within 14 days. Include the source of a sample of the recipient addresses. We review each appeal once; the outcome of that review is final. Confirmed use of purchased, rented or traded lists is not reversible.
- Truncus is the sole arbiter of AUP violations. Our decision is final.
- For zero-tolerance violations we may, at our sole discretion, refund payments already made and permanently close the account. A refund is a courtesy, not an entitlement, and does not constitute an admission that the suspension was in error. Re-registration after a zero-tolerance closure is prohibited.
Why This Exists
Truncus uses shared sending infrastructure. When one sender spams, complaint rates rise across the entire platform, affecting the deliverability of every customer. These rules protect your deliverability as much as they protect ours. We enforce them without exception because there is no other way to maintain a platform that works reliably for legitimate senders.