--- title: "Acceptable Use Policy | DuoCircle" description: "What you can and cannot do with DuoCircle products. Plain English. Enforced consistently. The rules that protect every customer" image: "https://www.duocircle.com/images/og-default.png" canonical: "https://www.duocircle.com/legal/aup/" --- # Acceptable Use Policy Last updated May 6, 2026 This Acceptable Use Policy (AUP) applies to every customer of every DuoCircle product. It exists to protect the deliverability and reputation of our shared sending infrastructure, the security of our customers’ inboxes, and the trust we have built with mailbox providers worldwide. The AUP is incorporated into the [DuoCircle Cloud Terms](/legal/cloud-terms/) by reference. ## What you must not do You must not use any DuoCircle service to: - Send unsolicited bulk email, scrape addresses, or buy lists. The CAN-SPAM Act and analogous statutes in other jurisdictions are minimum requirements, not aspirations. Recipients must have given clear, opt-in consent to receive email from the sending domain. - Send phishing, business email compromise, fraudulent, or otherwise deceptive messages, including any message that misrepresents its origin, intent, or affiliation. - Distribute malware, ransomware, exploit kits, or any executable, script, document, or link intended to compromise a recipient’s device or accounts. - Send content that is unlawful in the jurisdiction of the sender or any expected recipient, including content that infringes intellectual property rights, defames a third party, or constitutes harassment, hate speech, or threats of violence. - Send content that exploits or endangers minors, including child sexual abuse material under any definition in any jurisdiction. - Operate any spam relay, drop-in MX for spammed domains, snowshoe sending operation, or sending pattern that obfuscates the true source of mail. - Attack, probe, or interfere with DuoCircle infrastructure, the infrastructure of any other DuoCircle customer, or any third-party network. Penetration testing of your own DuoCircle account is allowed with prior written notice to [](mailto:security@duocircle.com)[security@duocircle.com](mailto:security@duocircle.com). - Resell DuoCircle services, white-label them, or repackage them without a separate written agreement. - Circumvent rate limits, billing, authentication, or any other technical or contractual control. ## What we expect of every sender - Maintain SPF, DKIM, and DMARC alignment on every domain you send from. Free tools at [autospf.com](https://autospf.com) and [dmarcreport.com](https://dmarcreport.com) are available if you need them. - Honor unsubscribes within ten business days, and immediately for transactional dispute notices. - Keep your bounce, complaint, and spam-trap rates inside industry norms. We will reach out before suspension if your numbers drift. - Treat your customers’ inboxes the way you would want yours treated. ## What we will do We monitor mail flow, complaint feedback loops, blocklist signals, and content patterns. When something looks wrong, we will: 1. **Reach out first.** In all but the most clear-cut abuse cases, we contact the technical or billing contact on the account before taking any action. 2. **Investigate proportionately.** Most AUP issues are mistakes (a misconfigured form, a forgotten archive blast, a compromised account) and most are fixed within an hour of a phone call. We start there. 3. **Suspend if necessary.** When investigation confirms ongoing abuse or imminent reputational risk to other customers, we suspend the affected service. We will continue to communicate during suspension and reinstate as soon as the issue is fixed. 4. **Terminate for cause** in the cases set out in the Cloud Terms, including persistent or willful AUP violations. ## How to report abuse If you received a message you believe was sent through DuoCircle in violation of this AUP, email [](mailto:abuse@duocircle.com)[abuse@duocircle.com](mailto:abuse@duocircle.com) with the full message including all original headers. We respond to all reports. Emails sent to the abuse address are read by a human within one business day. ## How this AUP changes We revise this AUP when industry practice, mailbox-provider requirements, or law changes. Material changes are announced thirty days in advance by email to the technical contact on each affected account and posted on this page with an updated revision date. Continued use of the service after the change constitutes acceptance. --- ## Questions about this document? DuoCircle LLC, 5965 Village Way, Suite 105-234, San Diego, CA 92130\. Email[legal@duocircle.com](mailto:legal@duocircle.com)for legal inquiries, or[support@duocircle.com](mailto:support@duocircle.com)for everything else. [All legal documents](/legal/) [Talk to an expert](/contact/) ```json {"@context":"https://schema.org","@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com","logo":{"@type":"ImageObject","url":"https://www.duocircle.com/images/duocircle-logo.png"},"description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. 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