How can I find out the holder/owner of a domain name?

It used to be possible to see all data of the domain name holder, such as address data and phone number.
Recently, with the introduction of increasingly strict legislation, this has become increasingly difficult to see.
This has everything to do with, for example, the privacy law and protection of personal data.
The WHOIS was always a public information source for disseminating data, this is no longer the case.

How can I still see the holder data?

Nowadays it is increasingly difficult to be able to see the holder data of a domain. This is to protect the owner's personal information. He or she then decides how much information can be shared.

If the owner of a domain wishes not to show the information anymore there is unfortunately no way to retrieve this data.

SIDN will no longer provide holder information through the WHOIS as of February 1, 2021.
SIDN has already announced that as of February 1, 2021, they will also no longer display holder information at all.
The registrant information can only be viewed if the registrant agrees.
If, as a domain holder, you want to have a copy of proof and hand it over to someone regarding the data held by SIDN, you can use the SIDN holder data retrieval tool.
After completing the form, an email is sent to the holder.

This email contains a link that can only be used 1 time and is only valid for 1 week.
Once you click on the link you will see the data.

What about other extensions?
Usually the WHOIS always contains the name of the holder. This can be a company or an individual.
However, this option is likely to disappear in the near future as well.
Some WHOIS parties offer a contact owner button instead, but not everywhere yet.

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