I've seen it mentioned in the Terms of Use of certain companies (thinking Fox.com) that people are not allowed to link to the company website going back to the 90s, but I've never actually seen anyone try to enforce that.

I don't know whether I find it scary or hilarious.

eta: the Fox terms haven't changed much: "If you are interested in creating hypertext links to the Site, you must contact Company at terms@fox.com before doing so."