미국 판례상 특허침해와 손해배상액의 산정 ―2개의 마이크로소프트(Microsoft) 사건을 중심으로―

Assessing the damages of the patentees in the case of patent infringement has been a headache for the judges and attorneys. 35 U.S.C. §284 allows lost profits and reasonable royalty calculated in the process of hypothetical negotiation as a proper compensation for the patentees. Courts has been developed a number of rules for easing the hardship of the practitioners involved. Entire Market Value Rule and 25% rule of Thumb are the ones among them. Entire Market Value Rule allows for recovery of damages based on value of entire apparatus containing several features. However, as the number of patents that has be utilized for a single product has been increased, the reasonableness of this Entire Market Value Rule has been criticized for the last 20 years. Lucent case CAFC rendered its decision that more prudential application of this rule in recognizing the functional relationship between the components and market demand. In addition, January of this year, another Microsoft case, Uniloc USA Inc. v. Microsoft Corp., 25% rule of Thumb was attacked by Microsoft and abolished by CAFC. The 25 percent rule of thumb has been a tool that has been used to approximate the reasonable royalty rate that the manufacturer of a patented product would be willing to offer to pay to the patentee during a hypothetical negotiation. These changes in US CAFC’s attitude toward damage calculation will be essential to know for our litigant and scholars in academia for the betterment of the tools for assessing reasonable royalty at hand.