[Analysis of invalid patents associated with schistosomiasis control filed by Chinese applicants].

The invalid patents associated with schistosomiasis control were retrieved in the Chinese Patent Database of China National Intellectual Property Administration, the Baiten database and the incoPat database, and the overall trends, legal status, types, patent indexing and technical fields of all retrieved invalid patents were analyzed. As of December 30, 2020, there were totally 859 patents relating to schistosomiasis control, and 512 were invalid patents, with an invalid rate of 59.6%. The number of patent applications and invalid patents peaked in 2018, including 71 patent applications and 53 invalid patents. Among the 511 schistosomiasis control-related invalid patents with complete records, there were 425 invention patents, 81 utility model patents and 5 design patents, and 219 patents (42.9%) were invalid due to the termination of the patented right and 292 (57.1%) due to loss of the right for patent applications. The major technical points included medicines (chemicals), basic research, devices and detections, and the specialized fields were mainly concentrated in A61P33, G01N33, C12N15, C07K14 and A01N65. Our data demonstrate a high invalid rate of patents relating to schistosomiasis control in China. Secondary development and mining of the invalid patents in relation to schistosomiasis are recommended to make use of their values in the national schistosomiasis elimination program of China.