Exhibit 4.1


 


 










SINOVAC BIOTECH LTD.


 


and


 


PACIFIC STOCK TRANSFER COMPANY


 


as Rights
Agent


 


AMENDMENT


 


TO


 


RIGHTS AGREEMENT


 


Effective
as of March 24, 2017





 


This Amendment (this
“Amendment”), dated as of March 24, 2017 to the Rights Agreement, dated as of March 28, 2016 (the “Rights
Agreement”), is between Sinovac Biotech Ltd., an Antigua and Barbuda company (the “Company”), and
Pacific Stock Transfer Company (the “Rights Agent”).


 


WHEREAS, the Company
and the Rights Agent have heretofore executed and entered into the Rights Agreement;


 


WHEREAS, the Rights
Agreement, under its current terms, will expire on the close of business on March 27, 2017;


 


WHEREAS, pursuant to
Section 26 of the Rights Agreement, the Company and the Rights Agent may from time to time supplement or amend any provision
of the Rights Agreement in accordance with the provisions of Section 26 thereof;


 


WHEREAS, the Board
of Directors of the Company has determined that it is in the best interests of the Company and the holders of the Rights to amend
the Rights Agreement as provided herein; and


 


WHEREAS, all acts and
things necessary to make this Amendment a valid agreement according to its terms have been done and performed, and the execution
and delivery of this Amendment by the Company and the Rights Agent have been in all respects authorized by the Company and the
Rights Agent.


 


NOW, THEREFORE, in
consideration of the foregoing and mutual agreements set forth herein, the Company and the Rights Agent agree as follows:


 


		1.	Amendments.



 


		1.1.	Section 7.1 of the Rights Agreement is amended to replace
the reference to “March 27, 2017” with “March 27, 2018”.



 


		1.2.	All references to the date of “March 27, 2017”
in Exhibit B (the Form of Right Certificate) and Exhibit C (the Summary of Rights to Purchase Preference Shares) to the Rights
Agreement shall hereby be changed to “March 27, 2018”.



 






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		2.	Capitalized Terms. Capitalized terms used herein
but not defined shall have the meanings given to them in the Rights Agreement.



 


		3.	Effect of Amendment. Except as expressly amended
hereby, the Rights Agreement shall remain in full force and effect in accordance with its terms.



 


		4.	Benefits of Amendment. Nothing in this Amendment
shall be construed to give to any Person or corporation other than the Company, the Rights Agent and the registered holders of
the Right Certificates (and, prior to the Distribution Date, the Common Shares) any legal or equitable right, remedy or claim
under this Amendment; but this Amendment shall be for the sole and exclusive benefit of the Company, the Rights Agent and the
registered holders of the Right Certificates (and, prior to the Distribution Date, the Common Shares).



 


		5.	Severability. If any term, provision, covenant
or restriction of this Amendment is held by a court of competent jurisdiction or other authority to be invalid, void or unenforceable,
the remainder of the terms, provisions, covenants and restrictions of this Amendment shall remain in full force and effect and
shall in no way be affected, impaired or invalidated. The parties hereto further agree to replace such invalid, void or unenforceable
provision of this Amendment with a valid, legal and enforceable provision that carries out the parties’ intentions to the
greatest lawful extent under this Amendment.



 


		6.	Governing Law. This Amendment shall be deemed to
be a contract made under the internal laws of the State of Delaware and for all purposes shall be governed by and construed in
accordance with the laws of such State applicable to contracts to be made and performed entirely within such State.



 


		7.	Counterparts. This Amendment may be executed in
any number of counterparts and each of such counterparts shall for all purposes be deemed to be an original, and all such counterparts
shall together constitute but one and the same instrument. A signature to this Amendment transmitted electronically shall have
the same authority, effect, and enforceability as an original signature.



 


		8.	Descriptive Headings. Descriptive headings of the
several Sections of this Amendment are inserted for convenience only and shall not control or affect the meaning or construction
of any of the provisions hereof.



 


[Signature page follows.]


 




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IN WITNESS WHEREOF, the
parties hereto have caused this Amendment to the Rights Agreement to be duly executed, as of the day and year first above written.


 





	 	SINOVAC BIOTECH LTD.
	 	 	 
	 	By:	/s/ YIN WEIDONG
	 	 	Name: YIN WEIDONG
	 	 	Title: Chairman, President & CEO
	 	 	 
	 	PACIFIC STOCK TRANSFER COMPANY, as Rights Agent
	 	 	 
	 	By:	/s/ JOSLYN G. CLAIBORNE
	 	 	Name: JOSLYN G. CLAIBORNE
	 	 	Title: Director, Global Operations Center







 






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