Exhibit
10.1


AMENDMENT
TO REGISTRATION RIGHTS AGREEMENT AND JOINDER


This AMENDMENT TO
REGISTRATION RIGHTS AGREEMENT AND JOINDER (this “Amendment”) is made and entered into as
of May 23, 2007, by and among Venoco, Inc., a Delaware corporation (the “Company”), the
Marquez Trust, a trust established under the laws of the State of Colorado (the
“Trust”),
and the Marquez Foundation, a Colorado non-profit corporation (the “Foundation”).


RECITALS


A.            The Company and the Trust are
parties to that certain Registration Rights Agreement, dated August 25, 2006
(the “Agreement”),
pursuant to which the Trust has the right to cause the Company to register
certain shares of common stock of the Company, par value $.01 per share (“Common Stock”) under
the Securities Act of 1933, as amended (the “Securities Act”), in certain
circumstances;


B.            Under the Agreement, the Trust has
the right to require the Company to effect up to three “Demand Registrations”
(as that term is defined in the Agreement) on Form S-1, an unlimited number of
Demand Registrations on Form S-3 and an unlimited number of “Piggyback
Registrations” (as that term is defined in the Agreement), in each case subject
to the limitations set forth therein;


C.            The Company is considering filing a
registration statement pursuant to which it would register Common Stock, debt
securities, warrants and/or other securities under the Securities Act (the “Registration Statement”)
and the Trust has exercised its right to include shares of Common Stock it
holds in the Registration Statement on a “piggyback” basis;


D.            The Trust desires to allow the
Foundation, which is an affiliate of the Trust, to include certain shares of
Common Stock it holds in the Registration Statement on a piggyback basis on the
same terms as are applicable to the Trust, and the Company desires to allow
such registration subject to the conditions set forth herein, including (i) the
Foundation’s agreement not to sell or otherwise dispose of shares of Common
Stock during the period specified in Section 3 hereof and (ii) the Trust’s
agreement to reduce its number of permitted Demand Registrations on Form S-1
from three to two.


AGREEMENT


In consideration
of the terms and conditions of this Agreement, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
the parties agree as follows:


1.             Joinder and Piggyback Right.  The Foundation hereby joins and becomes a
party to the Agreement to the following extent: 
The Foundation shall have the right to include shares of Common Stock it
holds in the Registration Statement (but not subsequent registration statements
filed by the Company) pursuant to Section 3 of the Agreement, and shall have
all the rights and obligations of the Trust with respect to such registration,
on the 



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same terms and conditions of the Agreement as are
applicable to the Trust in the case of a Piggyback Registration (including the “underwriters’
cutback” provision set forth in Section 3(b) of the Agreement); provided, however, that (i) the maximum
aggregate number of shares of Common Stock held by the Foundation and the Trust
to be included in the Registration Statement shall not exceed 2,500,000 and
(ii) the maximum aggregate number of such shares sold in the first underwritten
offering of Common Stock by the Company under the Registration Statement shall
not exceed 10% of the number of shares of Common Stock sold by the Company in
such offering.


2.             Amended Provision.  The first sentence of Section 2(c)(4) of the
agreement is hereby deleted and replaced in its entirety with the following:


Holders shall be entitled
to have a total of two Demand Registrations effected on Form S-1 (including any
successor form, “Form S-1”) and an unlimited number of Demand
Registrations on Form S-3 (including any successor form, “Form S-3”) at
any time when the Company is eligible to use such form.


3.             Foundation Lock-Up.  The Foundation agrees that it will not sell,
transfer or otherwise dispose of any shares of Common Stock that it holds as of
the date hereof or subsequently acquires, other than shares of Common Stock
included in the Registration Statement, for a period of  90 days following the date the Registration
Statement becomes effective, or such longer period as may be provided for in an
underwriting agreement entered into in connection with an underwritten offering
pursuant to the Registration Statement.


4.             No Other Changes. 
Except as modified or supplemented by this Agreement, the Agreement
remains unmodified and in full force and effect.


5.             Assignability. 
The Foundation may not assign or transfer any of its rights or
obligations under this Agreement in any manner whatsoever, and any purported
assignment or transfer shall be void.


6.             Validity. 
The validity or unenforceability of any provision of this Agreement
shall not affect the validity or enforceability of any other provision of this
Agreement, which shall remain in full force and effect.


7.             Counterparts. 
This Agreement may be executed in one or more counterparts, each of
which shall be deemed to be an original and all of which together will
constitute one and the same instrument.



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IN
WITNESS WHEREOF, the parties have executed this Amendment to Registration
Rights Agreement and Joinder effective as of the date first above written.


	
  

  	
   

  	
  VENOCO, INC.

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/ Bill
  Schneider

  	
   

  
	
   

  	
   

  	
   

  	
  Bill Schneider

  	
   

  
	
   

  	
   

  	
   

  	
  President

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  THE MARQUEZ
  TRUST

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/ Timothy
  Marquez

  	
   

  
	
   

  	
   

  	
   

  	
  Timothy Marquez

  	
   

  
	
   

  	
   

  	
   

  	
  Trustee

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  THE MARQUEZ
  FOUNDATION

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/ Timothy
  Marquez

  	
   

  
	
   

  	
   

  	
   

  	
  Timothy Marquez

  	
   

  
	
   

  	
   

  	
   

  	
  President

  	
   

  



 



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