地或限制對市場競爭的影響，在反托拉斯實務與文獻長期以來有著絕然對立的說法。芝加哥學派以為地域限制的產生，係緣於經銷階段搭便車的防止，有增加配銷效率的好處。相反的，傳統學派則認為地域限制制度，可能成為製造商暗地裡勾結的工具，不利於市場競爭的維持。 根據文獻兩種對立理論的主張，本文將其演化為可驗證的前提，並利用臺灣地區製藥業產的資料加以驗證。檢驗的結果發現:臺灣區製藥業地域限制的結果，傾向於支持效率說，對傳統的勾結說，則未能給予有力的支持。

　　　　　In antitrust literature and practices, totally opposite viewpoints on the issue of impact of territory restriction on market competition have been existing for a long time. The Chicago school considers that the formation of territory restriction is to prevent free riders in the distribution and marketing stage. Allocation efficiency can, thus, be enhanced by territory restriction. In contrast, the Classical School sees that territory restriction causes firms to collude. This in turn would decrease competition degree of the market. To empirically investigate these opinions, this study first proposes testable working hypotheses corresponding these opinions, then use data of Taiwan's pharmaceutical industry to perform the tests. The results show that territory restriction in Taiwan's pharmaceutical industry supports the efficiency hypothesis proposed by the Chicago School.