SVA [SINOVAC BIOTECH] 20-F: Indicate the number of outstanding shares of each
[Indicate the number of outstanding shares of each of the issuers classes of capital or common stock as of the close of the period covered by the annual report. 54,305,961 common shares as of December 31, 2010 o x o x x o o o] [List of Subsidiaries 1. Sinovac Biotech (Hong Kong) Ltd., a Hong Kong company 2. Tangshan Yian Biological Engineering Co., Ltd., a PRC company 3. Sinovac Biotech Co., Ltd., a PRC company 4. Sinovac Research and Development Co., Ltd. (formerly known as Beijing Sinovac Biological Technology Co., Ltd.), a PRC company 5. Sinovac (Dalian) Vaccine Technology Co., Ltd., a PRC company] [Certification by the Chief Executive Officer I, Weidong Yin, certify that: 1. I have reviewed this annual report on Form 20-F of Sinovac Biotech Ltd. (the “Company”); 2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of] [Certification by the Chief Financial Officer I, Jacob Chik Keung Ho, certify that: 1. I have reviewed this annual report on Form 20-F of Sinovac Biotech Ltd. (the “Company”); 2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in] [Certification by the Chief Executive Officer 2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company. EX-13.1 13 v219311_ex13-1.htm] [Certification by the Chief Financial Officer 2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company. EX-13.2 14 v219311_ex13-2.htm] [CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM We consent to the incorporation by reference in the Registration Statement (Form S−8 No. 333−161827) pertaining to the 2003 Stock Option Plan of Sinovac Biotech Ltd., of our reports dated April 22, 2011, with respect to the consolidated financial statements of Sinovac Biotech Ltd., and the effectiveness of internal control over financial reporting]