S.C. Code Ann. § 61-6-2820: Importation by registered producers.

No person other than a registered producer may ship, move, or cause to be shipped or moved alcoholic liquors from a point outside the State to a point inside the State, and then only in accordance with the provisions of this article. No brand may be registered by the producer unless the person registering the brand is either the American producer or the primary American source of supply in the United States of the brand as herein defined; and it is unlawful for a wholesaler in this State to order, purchase, or receive any alcoholic liquors from any producer who is not the primary American source of supply for the brand ordered, purchased, or received. The term "primary American source of supply" means the manufacturer, distiller, vintner, winery, or owner of vinous or spirituous beverages at the time it becomes a marketable product, or bottler, or the exclusive agent of any such person, who, if the product cannot be secured directly from the manufacturer by an American distributor, is the source closest to the manufacturer in the channel of commerce from whom the product can be secured by an American distributor, or who, if the product can be secured directly from the manufacturer by an American distributor, is the manufacturer.