특허권 침해에 대한 손해액의 감정

Calculation of Patent Infringement's Damages -Focusing on Using Damage Experts in US and Japan-

The determination of damages is a critical part of any patent case. Patent infringement damages are compensatory and should be the amount necessary to put the patentee in a position as good as it recover the actual damages. Compensatory damages, which is our principle of compensation, are monetary awards that are meant to compensate one person for losses caused by another person. Under this principle damages is recovered in payment for actual injury or economic loss, which does not include punitive damages. The amount of patent infringement damages is a question of fact. Compensatory damages are typically assessed against the breaching party. But proving the size of the damage is difficult for patentee because almost of evidence should be in infringer's side. Even if patentee received all evidence materials, it's also difficult to calculate the damages. Because patentees (or their attorney) without accounting knowledge could not understand the meaning of the numbers of the evidence materials. Due to those difficulties, in US, they use damages expert so-called the Masters and the expert witness in the patent litigation to calculate the damages. Japanese Patent Act also have applicable provisions to use an experts who calculate damages in patent litigation. Proper compensations is very important thing for effectiveness of patent system. In this respect, we study the way of using the accounting experts in US and Japan to estimating actual injury or economic loss for patent litigation.