Facing dominant retailers, brand-owners are witnessed to increasingly ally with the dominant retailers or other brand-owners. To study brand-owners’ alliance strategies, we consider a bilateral duopoly setting comprising two brand-owners and two dominant retailers. The brand-owners’ alliance strategies result in three typical structures: (1) a flexible structure, where each brand-owner sells products via any retailer; (2) a vertical structure, where a brand-owner sells product exclusively via an allied retailer; and (3) a horizontal structure, where the two brand-owners form an alliance by cross-shareholding. In each structure, bilateral contract negotiations between brand-owners and retailers are conducted, with consideration of demand substitutability and complementarity. We identify vertical alliance effect and horizontal alliance effect, which both lead to a more monopolistic wholesaling market in different ways. In the vertical structure, a win-win situation exists when demand is substitutable, while the incentives for the brand-owners and retailers on forming a vertical alliance are conflicting when demand is complementary. In the horizontal structure, a win-win region exists with respect to the revenue-sharing ratio for the brand-owners to form a horizontal alliance when demand is substitutable. In contrast, given complementary demand, their incentives to form a horizontal alliance become weak.

面对主导零售商，目睹品牌所有者与主导零售商或其他品牌所有者的盟友越来越多。为了研究品牌所有者的联盟策略，我们考虑了由两个品牌所有者和两个主要零售商组成的双边双头垄断环境。品牌所有者的联盟战略形成三个典型的结构：（1）灵活的结构，其中每个品牌所有者通过任何零售商销售产品；（2）纵向结构，品牌所有者仅通过联合零售商销售产品；（3）横向结构，两个品牌所有者通过交叉持股结成联盟。在每种结构中，品牌所有者和零售商之间都要进行双边合同谈判，同时要考虑需求的可替代性和互补性。我们确定垂直联盟效应和横向联盟效应，两者都以不同方式导致批发市场更加垄断。在纵向结构中，当需求可替代时存在双赢局面，而当需求互补时，品牌所有者和零售商建立纵向联盟的动机相互矛盾。在横向结构中，在收益共享比率方面存在一个双赢的区域，品牌所有者可以在需求可替代时形成横向联盟。相反，在需求互补的情况下，他们形成横向联盟的动机变得很弱。