미국 특허법에서의 특허침해로 인한 일실이익 산정방법— 일실판매에 의한 일실이익과 가격침식에 의한 일실이익을 중심으로 —

Historically the U.S. courts had adopted the legal principles about the method for calculating lost profit damages of lost sales and price erosion caused by patent infringement. The U.S. courts had adopted the “Panduit test” that is a general standard to Key Words : U.S. Patent Law, Patent Infringement, Damages, Lost Profit, Lost Sales, Price Erosion determine whether lost profit damages of lost sales could be recognized. Traditionally the courts had determined the second element of the “Panduit test”, namely “non-exsistence of acceptable noninfringing substitutes” in terms of “technical substitutability”. But, since 1990s the courts has determined the second element in terms of “economic substitutability” together with “technical substitutability”. And, the CAFC had lowered the standard to determine “acceptability of noninfringing substitutes” by deciding that noninfringing substitutes are likely to exist in the relevant product market could satisfy the acceptability requirement through the Grain Processing decision in 1999. Also, the CAFC had ruled that to get lost profit damages of price erosion, patentees should show that but for infringement it would have sold its product at higher prices as well as the reduced amount of product the patentee would have sold at the higher price through the Crystal Semiconductor decision in 2001. In the end, the Grain Processing decision and the Crystal Semiconductor decision had limited the damages resulting from patent infringement.