Exploring Valuable Indicators for Classifying Strong and Weak Patents Based on Invalidation Reexamination Decisions

Abstract Based on 8,666 invalidation reexamined China invention grant patents of decision dates from 2000 to 2021, the effect and value of eight indicators for classifying strong and weak patents in nine technology areas, including overall technology and eight technology sections, was thoroughly analyzed via ANOVA. Two high valuable indicators including abstract word count and examination duration for classification were found, which respectively showed significance in five technology areas. Four less valuable indicators, including claim count, figure count, inventor count and IPC count, were found to respectively show significance in one or two technology areas. A valueless indicator of applicant count was found to show none of significance in any technology areas. The strong patents did not always show higher indicator means of significance. Especially for the high valuable indicator of examination duration, the strong patents showed lower means in any of five technology areas of significance. The finding of this research would contribute the state of art in evaluating patents and help patent owners improve their patent asset management strategy. JEL classification numbers: C38, C46, G11, G12.