We develop a model in which each of m manufacturers forms a differentiated final product by assembling n components that are provided by its own n independent suppliers. Each supplier produces a unique component and sells to only one of the manufacturers. The manufacturers engage in product-differentiated Cournot competition. We show that if initially the number of manufacturers is sufficiently small, and if the number of components is large enough, then, as the number of manufacturers increases, every firm—including downstream manufacturers and their upstream component suppliers—earns more profit. Entry can increase every firm's profit. The package-tour industry of Japan is an example of such an industry. Drip coffee supplied by competing convenience stores in Japan is another.

中文翻译：

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垂直寡头垄断，进入增加每个公司的利润

我们开发了一个模型，其中m 家制造商中的每家都通过组装由其自己的n 个独立供应商提供的n 个组件来形成差异化的最终产品。每个供应商都生产一种独特的组件，并且只销售给其中一个制造商。制造商进行产品差异化的古诺竞争。我们表明，如果最初制造商的数量足够少，并且组件的数量足够多，那么随着制造商数量的增加，每企业——包括下游制造商及其上游零部件供应商——赚取更多利润。进入可以增加每个公司的利润。日本的旅行团行业就是这样一个行业的一个例子。日本竞争便利店提供的滴漏咖啡是另一种。