네트워크 발명의 특허권 침해 판단기준 - 국내 사용 의도와 이익실현지의 역할 -

Under established doctrine, patent infringement requires not only the satisfaction of general legal elements but, as a rule, the implementation of all elements of the patented invention within the territory of the jurisdiction in which the patent has been granted. This reflects both the all-elements rule and the principle of territoriality. The rapid advancement of communications technology, however, has placed significant pressure on these traditional principles. In particular, so-called “network inventions,” which can be implemented across multiple national jurisdictions, have prompted growing calls for a more flexible interpretation and application of territoriality. This study addresses the question: How should the all-elements rule and the principle of territoriality be reinterpreted and applied in light of the technological realities introduced by modern communications networks? To this end, it undertakes a comparative analysis of leading judicial decisions from major jurisdictions—including Korea, China, the United States, and Germany—examining the relevance of factors such as server location, place of economic benefit realization, and locus of system control in determining infringement. Based on this comparative analysis, this paper proposes the following criteria for determining infringement. First, if economic benefits are realized domestically through customer terminals located in the country, and if it can be established that the actor intended to achieve such cross-border economic realization, patent infringement should be recognized despite the absence of certain elements. This applies even when all components of a network invention except for the customer terminal are located abroad. While this legal approach significantly expands the traditional principle of territoriality, raising concerns from the perspective of legal stability, case law in major jurisdictions shows a tendency to accept some of these concerns in order to ensure effective patent protection. Notably, even Japan—which has long maintained the most conservative legal doctrine—recently (2025) saw its Supreme Court adopt a “place of benefit realization” criterion, demonstrating the inevitability of changes to existing principles. Second, the doctrine of separately determining infringement for product (system) inventions and method inventions in the context of network inventions is undesirable. In the U.S. case NTP v. Research In Motion, the court failed to properly assess the “control” factor and held that different criteria for determining infringement should apply to product inventions and method inventions. This reasoning overlooked the fact that, in method inventions, each step does not exist independently but is organically connected within the overall flow. The conclusion that infringement can only be recognized if all steps are performed within the relevant country fails to reflect the technological reality of how network inventions operate. Therefore, in determining infringement of network inventions, it is desirable not to distinguish between product and method inventions, but rather to adopt a standard whereby if customer terminals are located domestically and substantial benefits are realized domestically, infringement should be recognized. Naturally, damages should be calculated based on the sales generated domestically.