Exhibit
4.1


 


THIRD
AMENDMENT TO RIGHTS AGREEMENT


 


This Third
Amendment to Rights Agreement (this “Amendment”), dated as of July 25,
2005, to the Rights Agreement, dated as of February 25, 1999, between
BioSource International, Inc., a Delaware corporation (the “Company”),
and U.S. Stock Transfer Corporation (“USSTC”), as Rights Agent, as
amended on January 10, 2000 and as further amended on September 28,
2000 (as amended, the “Rights Agreement”).


 


WHEREAS, Section 26
of the Rights Agreement provides that prior to the Distribution Date, the
Company may and the Rights Agent shall, if the Company so directs, supplement
or amend any provision of the Rights Agreement without the approval of any
holders of certificates representing shares of Common Stock; and


 


WHEREAS, the
Company, Invitrogen Corporation, a Delaware corporation (“Parent”), and Errol
Acquisition Corporation, a Delaware corporation and a wholly owned subsidiary
of Parent (“Merger Sub”), have entered into an Agreement and Plan of
Merger, dated as of July 25, 2005 (the “Merger Agreement”),
pursuant to which Parent will acquire the Company; and


 


WHEREAS,
concurrently with the execution of the Merger Agreement, Parent, Genstar
Capital Partners II, L.P. and Stargen II LLC have entered into that certain Voting
Agreement, dated as of July 25, 2005, in respect of shares of capital
stock of the Company beneficially owned by Genstar Capital Partners II, L.P.
and Stargen II LLC (the “Voting Agreement”); and


 


WHEREAS, the
Company Board of Directors has determined that it is in the best interests of
the Company and its stockholders and consistent with the objectives of the
Board of Directors in adopting the Rights Agreement to amend the Rights
Agreement to except the Merger Agreement and the actions and transactions
contemplated thereby and effected in connection therewith from the Rights
Agreement; and


 


WHEREAS, the
Company has delivered to the Rights Agent a certificate, dated as of the date
hereof, of an appropriate officer of the Company certifying that this Amendment
is in compliance with the terms of Section 26 of the Rights Agreement and directing
the Rights Agent to execute and deliver this Amendment.


 


NOW,
THEREFORE, in consideration of the foregoing and other good and valuable
consideration, the receipt and sufficiency of which the parties hereby
acknowledge, the parties agree as follows:


 


ARTICLE I


 


AMENDMENT


 


1.1           Amendment to
Definition of “Acquiring Person”. 
The definition of “Acquiring Person” in Section 1 of the Rights
Agreement is hereby amended by inserting the following provisions at the end of
that definition:


 





















 


“Notwithstanding the foregoing or any
provision to the contrary in this Agreement, none of Invitrogen Corporation, a
Delaware corporation (“Parent”), its Subsidiaries, Affiliates or Associates,
including Errol Acquisition Corporation, a Delaware corporation (“Merger Sub”),
is, nor shall any of them be deemed to be, an Acquiring Person by virtue of (i) their
acquisition, or their right to acquire, beneficial ownership of Common Stock as
a result of their execution or delivery of the Agreement and Plan of Merger,
dated as of July 25, 2005 by and among Parent, Merger Sub and the Company
(as it may be amended from time to time, the “Merger Agreement”) or any rights
that accrue to any of them under, or arise in connection with the Voting
Agreement, dated as of July 25, 2005, by and among Parent, Genstar Capital
Partners II, L.P. and Stargen II LLC (the “Voting Agreement”), (ii) the
consummation of the Merger (as defined in the Merger Agreement) or the exercise
of any rights pursuant to the Voting Agreement, or (iii) any other action
or transaction contemplated by or effected in connection with the Merger
Agreement or the Voting Agreement, it being the purpose of the Company in
adopting this amendment to the Agreement that neither the execution or delivery
of the Merger Agreement nor the execution or delivery of the Voting Agreement
by any of the parties nor the consummation of the actions or transactions
contemplated thereby or effected in connection therewith shall in any respect
give rise to any provision of the Agreement becoming effective.”


 


1.2           Amendment to
Definition of “Stock Acquisition Date”. 
The definition of “Stock Acquisition Date” in Section 1 of the
Rights Agreement is hereby amended by inserting the following at the end of
that definition:


 


“Notwithstanding the foregoing or any
provision to the contrary in this Agreement, a Stock Acquisition Date shall not
occur by reason of the approval, delivery or execution of the Merger Agreement
or the Voting Agreement, the consummation of the Merger (as defined in the
Merger Agreement), or any other action or transaction contemplated by or
effected in connection with the Merger Agreement or the Voting Agreement.”


 


1.3           Amendment to
Definition of “Exempt Person”.  The
definition of “Exempt Person” in Section 1 of the Rights Agreement is
hereby amended and restated to read in its entirety as follows:


 


“Exempt Person” shall include: (i) the
Company, (ii) any Subsidiary (as hereinafter defined) of the Company, (iii) any
employee benefit plan of the Company or any of its Subsidiaries, or any entity
holding shares of Common Stock which was organized, appointed or established by
the Company or any Subsidiary of the Company for or pursuant to the terms of
any such plan, (iv) Genstar Capital Partners II, L.P., Stargen II LLC,
Jean-Pierre Conte, Robert Weltman, Richard Hoskins and Richard Paterson and
their respective Affiliates


 


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and Associates (collectively, the “Genstar
Capital Group”), and (v) Parent and its Subsidiaries, Affiliates and
Associates, including Merger Sub.”


 


1.4           Amendment to Section 3(a).  Section 3(a) of the Rights
Agreement is hereby amended by inserting the following at the end of Section 3(a):


 


“Notwithstanding the foregoing or any
provision to the contrary in this Agreement, a Distribution Date shall not
occur by virtue of the approval, delivery or execution of the Merger Agreement
or the Voting Agreement, the consummation of the Merger (as defined in the
Merger Agreement), or any other action or transaction contemplated by or
effected in connection with the Merger Agreement or the Voting Agreement.”


 


1.5           Amendment to Section 7(a).  Clause (i) in Section 7(a) of
the Rights Agreement is hereby amended and restated in its entirety to read as
follows:


 


“(i) (1) the close of business on January 31,
2009 or (2) immediately prior to the Effective Time (as defined in the
Merger Agreement) (the earlier of (1) and (2) being herein referred
to as the “Final Expiration Date”)”


 


1.6           Amendment to Section 13(b).  Section 13(b) of the Rights
Agreement is hereby amended by inserting the following provisions at the end of
Section 13(b):


 


“Notwithstanding the foregoing or any
provision to the contrary in this Agreement, none of Parent, its Subsidiaries,
Affiliates or Associates, including Merger Sub, is, nor shall any of them be
deemed to be, a Principal Party by virtue of (i) their acquisition, or
their right to acquire, beneficial ownership of Company Common Stock as a
result of their execution of the Merger Agreement, (ii) the consummation
of the Merger (as defined in the Merger Agreement), or (iii) any other action
or transaction contemplated by or effected in connection with the Merger
Agreement.”


 


1.7           Addition of Section 35.  A new Section 35 is hereby added reading
in its entirety as follows:


 


“Notwithstanding any provision of this
Agreement to the contrary, no holder of Rights shall be entitled to exercise
such Rights under or be entitled to any rights pursuant to this Agreement by
virtue of the execution or delivery of the Merger Agreement or the execution or
delivery of the Voting Agreement by any of the parties or the consummation of
the actions or transactions contemplated thereby or effected in connection
therewith.”


 


1.8           Addition of Section 36.  A new Section 36 is hereby added reading
in its entirety as follows:


 


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“This Agreement and the Rights established
hereby will terminate in all respects immediately prior to the Effective Time
(as defined in the Merger Agreement).”


 


1.9           Effect of Termination
of Merger Agreement.  If for any
reason the Merger Agreement is terminated or the Merger is abandoned, then this
Amendment shall be of no further force and effect and the Rights Agreement
shall be deemed automatically amended without further action to provide such
terms and conditions as existed immediately prior to the execution of this
Amendment.


 


1.10         Definitions.  Terms not otherwise defined in this Amendment
shall have the meaning ascribed to such terms in the Rights Agreement.  The term “Agreement” as used in the Rights
Agreement shall be deemed to refer to the Rights Agreement as amended hereby,
and all references to the Agreement shall be deemed to include this Amendment.


 


1.11         Governing Law.  This Amendment shall be governed by and
construed in accordance with the laws of the State of Delaware.


 


1.12         Counterparts.  This Amendment may be executed in any number
of counterparts and each of such counterparts shall for all purposes be deemed
an original, and all such counterparts shall together constitute but one and
the same instrument.


 


1.13         Effectiveness.  This Amendment shall be effective as of the
date first written above, and except as expressly set forth herein, the
Agreement shall remain in full force and effect and otherwise shall be
unaffected hereby.


 


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IN WITNESS
WHEREOF, the parties hereto have caused this Amendment to be duly executed as
of the date first written above.


 


 


	
   

  	
  BIOSOURCE INTERNATIONAL, INC.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Terrance J. Bieker

  	
   

  
	
   

  	
  Name:

  	
  Terrance J. Bieker

  
	
   

  	
  Title:

  	
  President and Chief Executive Officer

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  U.S. STOCK TRANSFER CORPORATION

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Syed A. Hussaini

  	
   

  
	
   

  	
  Name:

  	
  Syed A. Hussaini

  
	
   

  	
  Title:

  	
  Vice President

  
					



 


 


[SIGNATURE PAGE TO AMENDMENT
NO. 3 TO RIGHTS AGREEMENT]


 


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