The lifespan of semiconductor patents by assignee and patent characteristics

Science and Technology Policy Research and Information Center, National Applied Research Laboratories, Taipei 106, Taiwan

^a Corresponding author : shchang@narlabs.org.tw

Abstract

Evaluating the values of patents is critical for both managers and investors. Patent maintenance time is an ideal proxy indicator for evaluating commercial patent value. This study investigated the survival rates of patents in the semiconductor industry by using a survival analysis and incorporated a predictive model for patent maintenance times. The technical characteristics of the patents, the assignee factors, and the statuses of the patents were used as the predictive factors for patent maintenance time. The results revealed a small entity size and the number of assignees are the risk factors that increase the likelihood of the maintenance time of a patent decreasing. The litigation status of a patent and the number of its international patent classifications, claims, forward citations, and assignments were determined to be the protection factors that raise the likelihood of its maintenance time extending. Additionally, substantial differences were noted between small entities and nonsmall entities and between being litigated and not in their effects on the survival rates of patents. This study examined the factors that affect the survival rates of patents and provides a reference for the managers and investors of intellectual property rights to use when assessing technical and commercial patent values.