近來許多有關價格領導的案例,公平會處理上頗有相當難度。誠然,法院或公平會均認為價格領導導製的價格一致性行為,違反公平交易法第7條之規定。於台灣高度集中的市場中,黙示勾結的狀態持續進行不斷,然而政府該如何證明相互影響的一致的行動,即為寡占市場中的黙示勾結。中油與台塑公司的暗黙勾結的同步調漲、降價格,被描述為具有操控市場價格能力。黙示勾結與明示勾結均違反公平交易法第7條之規定,然而法院必須從經濟理論上證明,廠商間有合意的存在。 法院或公平會於欠缺強而有力的經濟分析,即認為價格領導係屬違法,本文對此看法表示質疑。基於此,傳統的經濟模型或賽局理論得以證明,縱然廠商間欠缺合意,仍可以達成Nash equilibrium,廠商最佳的策略乃追求利潤極大之目的前提下,設定價格與產量。 本文利用經濟模型分析,指出現行實務操作上的矛盾,併討論中油與台塑的案例,最後提供總結與建議。 In a spate of recent cases, the courts and the Fair Trade Commission (“FTC”) have difficulity regulating the cases of price leadership among competitors in olipolistic markets. Indeed, courts and FTC have condemned such concerted action in violation of the Fair Trade Law (“FTL”). The high levels of concentration in many Taiwan markets guarantee that tacit collusion will be continuing problem, however, how government proved coordinated interaction to assess the likelihood for tacit collusion in oligopoly Chinese Petroleum Co.and Formosa Platistic Co. raised or reduced gasoline prices simultaneously, the action was described the means by which firms in gasoline markets are able to manage the price having to enter into an unexpressed agreement. Tacit collusion, like express agreement, should be illegal on its face under Article 7 of FTC. However, the court need inquire into the specific economic evidence on the existence of meeting of mind. This article argues that courts recognizing price leadership is illegal because neiher courts nor FTC have explicitly grounded their analysis in modern oligopoly theory, which is the rational basis for evaluating economic evidence on the existence of collusion. In this regard, traditional models and game theory demonstrates that the mutually price and quantity constitute Nash equilibrium without agreements. Each party’s dominant strategy is to meet profit-maximizing, then is doing the best it can in setting a price and quantity. Each party independently reactions the same way. This study aimed to analyze the current economic theory to find out the predicament in practical operations. Furthermore, this paper briefly discuss Chinese Petroleum Co. and Formosa Platistic Co. cases, then provided a brief conculsion that summarized some of implication of proposed approaches.