​​“Proprietary” means something used or marketed under the exclusive legal right of the maker or inventor. In the wine world, the term “proprietary” is a term typically found on a wine label when the percentage of each type of grapes blended into a particular wine is the unique selection of the winemaker. Besides indicating that the wine is “special”, a proprietary label gives a winemaker flexibility in blending from year to year and creating a house style.