Department 56 is a company that manufactures and sells collectible Christmas village houses and other replica items to allow collectors to create the whimsical “Snow Village” town or “Dickens Christmas.” Department 56 has only authorized dealers. Sam’s Club, a division of Wal-Mart Stores, Inc., began selling Department 56 pieces from the Heritage Village Collection. Susan Engel, president and CEO of Department 56, refused to sell Department 56 products to Wal-Mart. Does her refusal violate any antitrust laws?