Research on Determinants of Invention Patent Examination Durations: The Patents of Photovoltaic Industry at the CNIPA

In the context of a surge in patent applications and rapid technological updates, exploring how to reduce patent backlog and how applicants optimize patent application strategies to enhance patent layout is a worthwhile question. Therefore, we collected invention patent applications in the field of photovoltaic industry filed in China from 1997 to 2020. Kaplan-Meier (KM) survival analysis and the Accelerated Failure Time (AFT) model were employed to analyze the factors influencing the examination duration of invention patents. The average examination period for invention patents in photovoltaic industry in China is 38.89 months. Factors like the number of claims, pages of specifications, international patent classifications (IPC), inventors, patentees, and scientific literature citations tend to prolong the time for a patent application to reach the endpoint. Conversely, factors like the number of patent families, engaging a patent agent, filing Patent Cooperation Treaty (PCT) applications, and opting for early publication contribute to a shortened patent examination period. Individual applicants experience longer waiting periods for authorization compared to other types of applicants. The study can serve as a reference for the government to enhance the operational efficiency of the patent examination system and provide guidance for patent applicants on how to expedite the examination period and obtain faster grant.