From practice
The legal-notice duty as a gateway for spam
In Germany the law requires every commercially operated website to state an email address openly. Address harvesters live on precisely that. A duty that holds open a door the operator is not allowed to close.
On the legal framework of this page. The provisions that follow are German and European law; this site is operated from Germany. Other countries have other rules — but many jurisdictions know comparable provider-identification duties, and wherever a reachable address is required the same problem arises. The technical core of this text is therefore independent of which law applies.
What is required
Anyone operating a commercial website in Germany must, under § 5 of the Digital Services Act (Digitale-Dienste-Gesetz, DDG), provide information that enables rapid electronic contact — including the electronic mail address. The email address is not one option among several here but named explicitly. The basis is a European directive, which is why equivalent rules apply in every EU member state.
The Court of Justice of the European Union clarified in 2008 that a second route to immediate communication alongside the address suffices, and that it need not be a telephone. A contact form will do — in addition, not instead. The address stays.
Why this is expensive
Collecting addresses is trivial. Programs read websites and look for the pattern of a mail address; the legal notice is the most reliable place to find one there is, because it sits at a predictable location and by law has to contain a real, working address.
You cannot change that address when it gets buried — it is in the legal notice. You cannot switch it off, because it has to be reachable. And you cannot filter it into unreachability, because then the duty is not met.
That is the peculiarity of this duty: it requires not merely opening a door but keeping it permanently open — to everyone, including those who come only because of it.
The usual ways out, and why they are no good
- The address as an image. No obstacle to harvesting programs any more, but a genuine barrier for people with impaired sight — and legally dubious, because information you have to type out by hand does not enable rapid contact.
- Paraphrases like "name (at) domain (dot) com". Trivial to reverse, and German courts have repeatedly held that information which is not directly usable does not satisfy the duty.
- A contact form alone. That satisfies the second route, not the first. The address is named explicitly in the statute.
- A throwaway mailbox. Contradicts the purpose: the information is meant to establish reliable reachability, not formal reachability.
What is left: write the address out in the open and bear the consequences.
What actually helps
Since the door has to stay open, everything shifts to what happens behind it. For this site that looks like this:
- Filtering by score, not rejection. Incoming mail is scored and, where suspicious, filed into a separate folder, but not refused. For an address that has to be reachable by law, a wrongly rejected message is the more expensive mistake.
- Delay as the first hurdle. Unknown senders are temporarily refused on their first attempt. Proper mail servers come back, bulk senders frequently do not — more on this under reputation.
- Regular review. The folder of filtered-out mail gets looked through, so that a wrongly filed message does not get lost. That is the part no software takes off your hands.
And the form
The second route of communication has a problem of its own: a form is an invitation to automatic form-fillers. The usual way out — a captcha service — means reporting every visitor to a third party just to protect a form. On a site that otherwise loads no external content, that would be the largest single item in the privacy policy.
It can be done without, with four hurdles that run entirely on our own server:
- An invisible field. Not rendered for humans, just another field for form-filling programs. Anyone who fills it in is not a human.
- A timing check. Between opening and submitting, humans take a while. Four seconds is not a while.
- A signed marker. The form carries a timestamp with a cryptographic signature. Anyone posting straight to the receiving address without having loaded the form has none. The signature is necessary because without cookies there is no server-side place for the time to be recorded.
- A quota per sender. All that is stored for it is a hash with a daily changing addition, which expires after hours.
One important detail at the end: anyone who trips one of these hurdles still gets the success message. Someone who notices they were turned away tries a different way — someone who believes they got through stops.
The actual observation
Here a legal duty meets a property of the system, and taken on their own both are sensible. The legislature wants providers to be reachable — quite right. The email system has no way of limiting unwanted mail at the source — historically explicable.
That the provisions here are German ones is secondary. Wherever a provider has to be reachable and that reachability is established through email, the same conflict of aims arises — only the section numbers are different.
Out of the two together comes a duty whose fulfilment permanently generates effort nobody is answerable for. The legislature has not created a spam problem; it has placed a requirement on a system that cannot meet it free of charge.
A delivery system in which being reachable does not mean being reachable by everyone would have no conflict of aims here. That email cannot distinguish between those two things is not negligence — it is a decision from a time when nobody needed the distinction.