Terms which become generic can be cancelled under:

The failure to use a mark for what period of time would tend to show that the mark has been abandoned?

Naked licensing means:

Lewis owns a catering business called "Lewis' Loud Lobster Barbecue." He has registered the arbitrary mark and has properly maintained the registration. Over the past several years, various Loud Lobster Barbecue catering companies have sprung up in the towns near where Lewis lives and operates. He recalls hearing something about this from a few of his clients, and his mother even called one day incorrectly thinking that her son had finally expanded his business and she was oh so very proud. Lewis is a laid back guy who is happy with the business he generates and doesn't mind if others use his mark, as long as they don?t encroach on his territory. The main problem here is that:

In the University Bookstore v. Board of Regents case, the court found that the mark in question had not been abandoned despite the use of the mark by multiple unauthorized parties for a period in excess of two centuries (!) because: