Should You Block Parked Domains?

Parked domains are not dangerous per see, but blocking them may be part of more general safety measures: First, it is obvious that it is not the place you intended to go, so it may be safer to keep you from reaching an unexpected place.

Why are parked domains bad?

Domain parking becomes harmful when, for example, cybercriminals compromise registrars' or resellers' networks. They might take control of the name servers (typically created by the registrar at the time of domain registration) of a parked domain and configure them so they can be part of malicious schemes.

Are parked domains bad for SEO?

With parked domains in place, they will all point to the same web content. Some experts argue that having parked domains is bad for SEO and it is better to use domain redirects, as they avoid the possibility of search engines penalising a site for duplicate content.