Factors affecting patent applicant choice of International Searching Authority

The PCT applications can be an indicator of patented technologies that firms consider important and valuable. Since an International Search Report (ISR) is the primary information that determines the value of the PCT application, it is the most important point thorough the PCT filing process for the PCT applicant to choose an appropriate ISA who issues the ISR. The author analyzed WO patent publication data and found which IP office as ISA tend to be chosen by PCT applicants, especially by the US applicants. The result shows that many PCT applicants have chosen EPO as ISA, and many US companies have been influencing this tendency. The author also found that the tendency differs from the entities of PCT applicants, that is to say, while universities/laboratories, hospitals and foundations in the United States tend to select UPSTO as ISA, many US companies select EPO as ISA. The results also shows that a part of the US applicants who filed pct applications with uspto have selected kipo, because of korea's technological specialisations in certain fields.