MastroSDR.

Acceptable Use Policy

Last updated 1 August 2026

MastroSDR is a cold outreach tool. Used well, that means a relevant message to someone with a genuine business reason to hear from you. Used badly, it is spam, and it damages your domain, our platform and the people receiving it. This policy is the line.

You must

  • Send only from a domain you own and have verified.
  • Identify yourself and your company honestly in every email.
  • Keep a working unsubscribe link in every message. MastroSDR adds one; do not try to defeat it.
  • Honour every opt-out immediately and permanently.
  • Include a real physical postal address.
  • Have a lawful basis for contacting each recipient under the rules that apply to them, including CAN-SPAM, CASL, GDPR and PECR.
  • Keep your prospect lists sourced legitimately and reasonably current.

You must not

  • Send to purchased, scraped or rented lists you cannot account for.
  • Use false or misleading sender names, subject lines or reply-to addresses.
  • Contact anyone on your do-not-contact list, or try to circumvent it.
  • Send to addresses that have hard bounced.
  • Send unsolicited email to consumers where the law requires prior consent.
  • Send phishing, malware, fraud, adult content, or promotions for illegal products or services.
  • Harass, threaten or repeatedly contact someone who has asked you to stop.
  • Impersonate another person or business.
  • Use the platform to test or launder sending reputation for a third party.

Automation and agents

You may drive MastroSDR with your own software or an autonomous agent through our API. That does not change anything above: you remain responsible for every message an agent sends under your key, exactly as if you had clicked send yourself.

Grant agents the narrowest scope that does the job. If an agent only needs to draft, do not give it messages:send.

How we enforce this

Hard bounces and spam complaints reported by your delivery provider are added to your do-not-contact list automatically and cannot be removed. Sustained abuse of this service may result in your account being suspended.

Reporting abuse

If you received an unwanted email sent through MastroSDR, use its unsubscribe link and, if the sender ignores it, tell us at abuse@mastrosdr.com. Include the full message headers if you can.