A while ago the univerity of Harvard registered the domain name harvard.xxx
Harvard mainly did this to prevent that someone else would register this name and put ‘adult’ content on this website. Harvard isn’t the first to do so, many other universities and large companies already registered their domain name under the .xxx extension.
They did this in order to block their name under .xxx. Like this they weren’t obliged to link a website to this name but they could prevent someone else from registering this name and putting explicit content on it.