Sinovac Biotech Ltd. (Chinese: 科兴控股生物技术有限公司, Nasdaq: SVA) is a Chinese biopharmaceutical company that focuses on the research, development, manufacture, and commercialization of vaccines that protect against human infectious diseases. The company is based in Haidian District, Beijing in China. The company is listed on the NASDAQ but the exchange halted Sinovac's trading in February 2019 due to a proxy fight.