Permission marketing requires the permission of the customer to receive interesting information and advertising messages via e-mail. The aim is messages tailored to the customers which are really of interest to them. Permission marketing is therefore one of the most efficient forms of advertising. The click rates of e-mails are between 5 and 15 per cent and are considerably higher than those of conventional forms of online marketing such as banner advertising.

If direct marketing measures are used without express permission, it is spamming. According to an EU study, spamming causes economic damage of more than 9 billion Euros per year in Europe alone.

To limit this damage and increase the attractiveness of the e-mail for marketing purposes, the registration process for inclusion in distribution lists is subject to statutory regulations. Double opt-in is now recommended. With this method, the subscription must confirm registration by e-mail in order to prevent involuntary entry by third parties.  

The anti-spam policy of Inxmail GmbH strictly opposes spam. Therefore, not only is Double Opt-In integrated in the software but also a spam check module. This philosophy is reinforced, among other things, by white-listing and the code of honour of  eco and the DDV Verband.