本文建立一個上下游模型以探討中間財廠商的訂價策略對其自身利潤及最終財廠商的經營型態的影響。假設上游有一獨占的中間財廠商，對下游的兩國最終財廠商提供中間要素，其訂價策略可採取單一訂價或差別訂價，兩最終財廠商則可選擇從事跨國經營，因而可能產生三種不同的市場經營型態：雙邊獨占、單邊雙占和雙邊雙占。
本文發現，當上游的中間財廠商採差別訂價且兩國的最終財市場規模差距相對較大時，下游的兩最終財廠商會比較偏好雙邊雙占的市場型態，而非雙邊獨占；當上游的中間財廠商採單一訂價且本國的最終財市場規模相對較小時，本國會歡迎他國的最終財廠商進入本國市場。這些發現明顯不同於過去相關文獻認為廠商偏好獨占市場之論點。

This article establishes a vertical-related model to discuss the pricing strategies of the upstream firm and the impacts on its own profit and the business models of the downstream firms. We assume there is an upstream monopoly firm that offers intermediate inputs to the two downstream firms in different markets and countries. The upstream firm may adopt uniform pricing or discriminatory pricing. And the downstream firms whether to engage in transnational operation depends on their benefits, therefore there may be three business models in the downstream market: firms are monopolistic in their own markets (bilateral monopoly), only one of firms is monopolistic (unilateral duopoly), and firms compete with each other (bilateral duopoly).
The major findings of this paper are that: when the upstream firm adopts discriminatory pricing and the differences of market sizes in the two countries downstream are large enough, both downstream firms will prefer the bilateral duopoly rather than bilateral monopoly; when the upstream firm adopts uniform pricing, the downstream firm whose original market size is relatively small in its country will greet with competition. These results are different from the past article: the firms prefer monopoly in their own market.

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