本文研究在垂直結構的市場中，上游製造商通過加工原材料製成中間財出售給下 游零售商，零售商加工中間財製成最終財出售給消費者;除此之外，還存在一家類似 於政府機構的，以社會福祉最大化為目標的第三方認證機構。在此環境下，上下游廠 商分別能接受何種程度的認證標準檢定成本，認證機構應如何設定認證標準使社會總 福祉盡可能最大化。最終本文發現，當得知對方廠商參與認證會使自廠商對認證標準 成本的接受程度提升，換言之，上下游雙方都希望對方能夠參與認證標準檢定;對認 證機構而言，其他條件不變的情況下，兩家廠商參與認證一定比只有一家廠商參與認 證社會福利來得大，當消費者逆需求函數斜率小於某種程度後，上游廠商才有可能接 受令社會福利最大化之認證標準，而下游廠商無論如何都不會接受社會福利最大化之 認證標準。 ;This paper studies, in a bilateral monopoly market where exists two firms, one is upstream manufacture and the other one is downstream retailer, what level of the certified CSR can be set by a certifier that the manufacture and retailer will adopt and fulfill it to increase their revenue and how the certifier to set the standard to maximize the social welfare.We find when the manufacture or retailer finds out that the other firm participates in the certified CSR, the manufacture or retailer will adopt a higher standard of certification, which means whether the manufacture or the retailer hopes the other firm to adopt the certification. And the social welfare brought by both manufacture and retailer adopting the certification is greater than only one of them participation. For the certifier, at most times it can only set a standard which is lower than the optimal one to induce firms to adopt the standard. However, only when the absolute value of the slope of the inverse demand function becomes very large, the manufacture may adopt the optimal standard which maximizes the social welfare.
