SIDN and privacy

Our work registering and managing domain names involves processing personal data on a daily basis. Naturally you can rely on us to take your privacy seriously. The privacy rules that we follow are described in the General Terms and Conditions for .nl registrants (Article 23).

Why is information about you visible in the Whois?

Around the world, it's usually possible to look up details of registered domain names. We allow the look-up of very limited information about .nl domain names. The only information about a private registrant given in the Whois is the administrative contact's e-mail address. If the registrant is a business, the name is shown as well, and the registrant can choose to give an address. You can use information from the Whois for the following: • To sort out technical problems that affect how the internet works • To trace the registrant of a .nl domain name you would like to acquire • To protect intellectual property rights • To stop illegal and harmful content being put on the internet, or to get it taken down

.nl image privacy

You can ask to opt out of sharing info about yourself

Do you have a special reason for not wanting the Whois to show even the small amount of info about you that would normally be available? (That's your e-mail address and, if you are a business registrant, your name.) If so, you can ask to opt out of sharing your personal details. The situations in which you're allowed to opt out and the procedure for opting out are described on the Opt-out request page.

Full contact details

In the Whois, you can look up certain details about a registered .nl domain name, including the e-mail address of the administrative contact person for the registrant. We also keep a few other pieces of information, which aren't visible in the Whois:

  • The registrant's name (not in the Whois if the registrant is a person)

  • The registrant's address

  • The name and phone number of the administrative contact for the domain name

  • The name and phone number of the technical contact for the domain name

What if you need to contact a registrant?

We suggest you try the following:

  • See whether the domain name is linked to a website with a contact page.

  • Try contacting the registrant using the administrative contact's e-mail address or the technical contact's e-mail address, both of which are in the Whois.

  • If the registrant is a business, get the name from the Whois. You can then google the name or look it up in the Trade Register.

  • Try contacting the registrant through the registrar, whose details are in the Whois. Every domain name is managed by a registrar (hosting service provider).

Occasionally, we do share a registrant's details

We share details only where there's a good reason. That comes down to sharing with the following:

  1. People with a legitimate interest ('interested parties')

    If you want us to give you a registrant's full contact details, you need to explain to us why you need them. We will then see whether your request satisfies the criteria in the Whois Conditions of Use.

    To request details about a .nl registrant, you need to use the request form for contact details.

  2. Investigative and enforcement authorities

    The police and others with similar powers can require us to give them full details of a registration.

    Automated data access for investigative and enforcement authorities

    The police and others with similar powers can make arrangements with us to look up personal data automatically. That saves us and them a lot of trouble. Naturally, the authorities are allowed to use their special access only as permitted by the law. We have arrangements with the following:

  3. Certification Authorities (CAs)

    CAs are companies that issue digital certificates to domain name registrants. Before issuing a certificate, a CA has to check whether the details match the data held by the registry. Because it is the registrant that wants the certificate, we cooperate with the CA.

    Automated access for CAs

    CAs can also make arrangements with us to look up personal data automatically. Naturally, CAs are allowed to use their special access only to get data on the registrant's behalf. We currently have arrangements with the following CAs:

Do you represent a CA with an interest in automated data access? You can request access using the agreement form Use of the Certification Authorities' Whois.

Frequently Asked Questions

No, the Whois can be used only to check who the registrant of a particular .nl domain name is. Reverse lookup isn't possible.

You are a private registrant if you register a domain name for yourself, not for a business or an organisation of another kind. If you are acting for a business or another organisation, you are a business registrant.


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