專利制度之博奕分析－－以軟體專利為例

From Prisoner's Dilemma to Assurance Game: A game-theoretical Analysis of Patent Debate

在現實狀況下，對個人有利之選擇，通常係以犧牲公共利益爲其代價，專利戰爭之亂象爲一明顯之案例，尤以軟體專利爲甚。因濫行專利訴訟以獲取額外利潤之商業策略，已驅使各產業爲保持市場優勢，競逐類似「軍備競賽」之專利戰爭，亦即博奕理論（game theory）所謂之「囚犯困境」賽局。此個人私益永遠凌駕於群體利益之上的囚犯困境現象顯已背離專利制度之本旨。準此，諸多法律學者建議修改現行專利政策以符合設立專利制度之本旨。本文嘗試從博奕理論之角度來討論該等建議之可行性，因依據博奕理論之觀點，任何爭論均可視爲一個賽局。據此類推，專利戰爭亦可視爲是一種賽局。又博奕理論揭示，如想改變賽局結果，唯有改變遊戲規則，始可能扭轉局勢至預期之結果。而法律伴隨處罰威嚇之角色，頗類似博奕理論所謂具有改變遊戲規則之功能，倘運用得當，專利政策之修正將有助於將專利戰爭由各謀其利之「囚犯困境」現象，導正爲符合專利制度本旨之「保證賽局」。

In the real world, sometimes something which is good for private interests is perhaps against society's interest. The argument of software patent may be such a case. It is because the practice of business patent strategies has led to patent wars amongst IT firms. And like arms races, the current patent war operates as a prisoner's dilemma. However, according to the spirit of patent law, this paper argues that an ideal patent law should work as an assurance game, rather than as a prisoner's dilemma. Legal scholars have provided useful suggestions to modify the current patent policy. This paper interlinks their works by using game theory as a theoretical base to underpin their arguments. In terms of game theory, any argument is seen as a game. And if wanting to improve it, we need to change the game rules and then the game result can be altered to what we desire. On this view, legal intervention, through the functions of punishment and focal point, can cause the change of game rules of any problem in question. Applied to the patent war case, it implies that, if well implemented, strengthening the patent law as an administrative law (market regulation) can turn the current development of patent war from a prisoner's dilemma game to an assurance game.