Second. Among the top 20 vaccine-related patents, Pleco Bioengineering Co., Ltd., which ranks first, has a total of 330 patents. The company mainly develops veterinary vaccines, and Qingdao Yibang Bioengineering, which ranks second, has a total of 330 patents. Co., Ltd. and China Animal Husbandry Industry Co., Ltd., ranked third, also focus on the research and development of veterinary vaccines. Qingdao, also known as Daocheng, Qindao and Jiaoao, is a prefecture-level city, sub-provincial city, separately planned city and megacity under the jurisdiction of Shandong Province, China.