Well, except for any trademark. As in, if they have "Legend of Zelda" trademarked, failing to protect their trademark means they risk losing the trademark. They probably don't have the title trademarked (for creative works, copyright is more important and more relevant,) but corporations (and, more to the point, corporate lawyers) aren't ones to take chances.
To put it another way, any intellectual property has a finite value associated with it referred to as "brand equity." If you let other people use your intellectual property, then you are lose some of that brand equity.