I am aware of another micro-distillery that recieved a call and letter from Makers Mark regarding the trademark of the red wax seal random drip pattern. The distiller had been using a similar design (and color) on a 375 ml brandy bottle, produced in small quantity and distributed locally. Neverthelss, Makers Mark did defend their trademark. I believe that the Makers Mark claim had been limited to the color red. In reading the link provided in this string regarding the trademark, it does seem to indicated that it is for Whiskey, but in this instance they objected to the red wax drip on a brandy bottle.
By the way, if you want to learn how Makers Mark does it, you can visit the distillery and dip a bottle yourself. It is part of the tour. And they will even give you a red bib to wear and take your picture doing it. Pretty cool, actually. And the bourbon tastes good too.