In 1993, Tangshan Yian Biological Engineering Co., Ltd., herein after as Tangshan Yian, was incorporated in the City of Tangshan, Hebei Province, . Mr.Weidong Yin was nominated as general manager of the company. Tangshan Yian owns proprietary production technology and conducts production and sales of hepatitis A diagnostic reagent. In 1995, “Inactivated Hepatitis A Vaccine R&D Project (Industrialization)”, applied by Tangshan Yian, was included in “The National Ninth Five Key Sciense and Technology Plan in Medical Scienses” . The vaccine was successfully developed in 1999 And New Drug Certificate and Production License were granted in the same year. It symbolizes naissance of the first inactivated hepatitis A vaccine in . At the same time, the R&D on combined Hepatitis A&B vaccine and influenza vaccine were initiated.

In order to realize the industrialization of inactivated hepatitis A vaccine, on April 28, 2001, Sino Pharma, Shenzhen Kexing, and Tangshan Yian invested to setup a new company in Beijing , named Sinovac Biotech Co., Ltd. The construction of the manufacturing workshop for inactivated hepatitis A vaccine was completed in 2002. The GMP certificate was received in the same year. The sales of inactivated hepatitis A vaccine, named HealiveTM, started in July of 2002. The market penetration was very effective and the sales of 2004 is over one million doses.

In Sep. 2003, Sinovac was listed on Nasdaq OTCBB.

And then it moved to American Stock Exchange and the stock started to be traded there on Dec. 8 2004, quote SVA.