FastMail.FMaccounts are designed for use by individuals (personal, in a family or in a business) for day to day regular receiving and sending of emails on a one-to-one basis to recipients who know you and expect to receive your email.
FastMail.FM no longer allows the sending of any bulk, duplicative or unsolicted emails under any circumstances.
Users that fail to comply with these rules will be regarded as breaching our Terms Of Service that they agreed to on signup, and will have their account locked.
Section 4
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By way of example, and not as a limitation, you agree not to: Use the Service in connection with ... any duplicative or unsolicited messages