Longer Patent Life Representing Higher Value? A Study on China Stock Market and China Patents

Abstract By setting the market capitalization as the frame of patent value reference, twenty-two quarter’s market capitalization from 2016Q1 to 2021Q2 of China listed companies (A-shares) were collected. All valid patent data of three patent species including the invention grant, the utility model grant and the design grant, were retrieved for calculating the average patent life of each A-share. The variances of the market capitalization via different patent life groups were analyzed via ANOVA. The A-shares having invention grant’s patent lives above the general level usually showed higher market capitalization means than the A-shares having invention grant’s patent lives below the general level. The invention grants with longer patent life might be regarded as the patents of higher value. The utility model grants with longer patent life might not be regarded as the patents of higher value because of poor significance. The design grant’s patent life was a significant indicator for discriminating China A-share’s market capitalization, however, the optimal patent life were close to but not longer than four years. The longer patent life of the design grants was not regarded as higher value. JEL classification numbers: C38, C46, G11, G12. Keywords: patent, market capitalization, China A-share, patent life, ANOVA.