Execution
Version




STOCKHOLDER
AGREEMENT





This
agreement, dated as of March 2, 2010 (the “Agreement”), among
La Cortez Energy, Inc.
(the “Buyer”),
a corporation organized under the Laws of Nevada with an address at Calle 67
#7-35, Oficina 409, Bogota, Colombia, Avante Petroleum SA(the
“Seller”), a
corporation organized under the Laws of Luxembourg with an address at 11b
Boulevard Joseph II, 1840 Luxembourg, and for purposes of Section 3.3 only,
Nadine Smith and Andres Gutierrez (collectively
“Shareholder
Parties” and each a “Shareholder
Party”).





WITNESSETH:





WHEREAS,
the Buyer and the Seller have entered into a Stock Purchase Agreement of even
date herewith (the “Stock Purchase
Agreement”), pursuant to which the Buyer shall acquire 100% of the
outstanding shares of Avante Colombia S.a.r.l., a current subsidiary of the
Seller, in consideration of the issuance to Seller of 10,285,819 newly issued
shares of common stock, $0.001 par value per share, of the Buyer (the “Common
Stock”).





WHEREAS, in connection with the
acquisition, the Seller and the Buyer have entered into the Subscription
Agreement, pursuant to which the Seller shall purchase additional shares of
Common Stock; and





WHEREAS,
it is a condition precedent to the obligations of the Parties under the Stock
Purchase Agreement that the Parties enter into this Agreement;





NOW, THEREFORE, in consideration of the
foregoing premises and the respective representations and warranties, covenants
and agreements contained herein, the parties hereto agree as
follows:





SECTION
1. Definitions.





(a)           Capitalized
terms used, but not defined herein, shall have the meaning given thereto in the
Stock Purchase Agreement.





(b)           In
addition to the terms defined elsewhere herein, when used herein the following
terms shall have the respective meanings indicated below:





“Board” shall mean the
Board of Directors of the Buyer.





“By-Laws” shall mean
by-laws of the Buyer.





“Capital Stock” shall
mean the shares authorized for issuance by a company’s charter, including both
common stock and preferred stock.





“Director” shall mean
a member of the Board.





“Non-Party” shall mean
a Person who is not a party to this Agreement.








“Shareholder” and
“Shareholders” shall mean the shareholder or shareholders of the
Buyer.





“Shares” shall mean
the shares of the Buyer’s Capital Stock.





“Stock Purchase
Agreement” shall have the meaning ascribed to it in the
recitals.





“Transfer” shall mean
any direct or indirect transfer, sale, assignment, pledge, encumbrance,
hypothecation or other disposition, whether with or without consideration and
whether voluntarily or involuntarily or by operation of law.





SECTION
2.Ownership of
Shares.  Upon the Closing under the Stock Purchase Agreement
and the closing of Seller’s purchase of the Definite Shares (as defined in the
Subscription Agreement) and the Contingent Shares (as defined in the
Subscription Agreement) under the Subscription Agreement, and assuming Buyer
closes on the sale of an aggregate of $5,000,000 of units in Covered Offerings,
then Seller will own the number and the percentage of issued and outstanding
Shares as follows:





Number of Shares
                        
                        Percentage13,142,962
                        
                        ~
      32.86%





SECTION
3.            Director
Nomination.





3.1.            Upon
the closing of the Stock Purchase Agreement, the Board shall increase the number
of Directors constituting the Board by one to create vacancy, pursuant to the
By-Laws. The Board shall appoint one Director, nominated by the Seller and
reasonably satisfactory to the Buyer (such person, or any successor thereto
nominated by Seller and reasonably satisfactory to the Buyer, the “Nominee”), to fill
the vacancy on the Board so created, to serve until the next annual meeting of
Shareholders or until his successor is duly elected and qualified or his earlier
death, resignation or removal in accordance with the By-Laws.





3.2.            The
Buyer shall continue to nominate the Nominee at the next and subsequent annual
meetings of the Shareholders, and at any special meeting of the Shareholders at
which Directors are to be elected (collectively, a “Meeting”) as long as
Seller and/or its Affiliates own outstanding Shares representing 10% or more of
the votes entitled to be cast at the applicable Meeting, but the Nominee will be
subject to reelection by the stockholders as provided in the By-Laws. If the
Nominee is not elected by the Shareholders pursuant to the By-Laws, the Seller
shall have the right to designate the same or another person as its Nominee at
the next Meeting, provided Seller and/or its Affiliates own outstanding voting
Shares representing 10% or more of the votes entitled to be cast at the
applicable Meeting.


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3.3.            Each
Shareholder Party shall vote any Shares owned by such Shareholder Party, or
cause any Shares owned by any immediate family member or Affiliate of such
Shareholder Party to be voted, in favor of the Nominee at any
Meeting.





3.4            
In addition, for so long as Seller is entitled to name a Nominee for election as
a Director, as provided above, the Seller shall have the right to appoint one
additional non-voting observer (the “Observer”) to attend
meetings of the Board, and the said Observer shall have the right to visit the
Buyer’s offices, to have interaction with Buyer’s management and to receive
information and documents pertaining to the Buyer as reasonably requested,
subject to the confidentiality provisions below.





SECTION
4.Special
Committee.    For a period ending on the earlier of
(i) 18 months after the Closing under the Stock Purchase Agreement or (ii) the
first date on which the Seller and/or its Affiliates no longer own outstanding
voting Shares representing ten percent (10%) or more of the votes entitled to be
cast at any annual or special meeting of Shareholders (if a record date for such
a meeting were established on any day), in the event that the Buyer (or the
Board) should propose to (i) merge or consolidate with or into any other
corporation (if the holders of voting stock of the Buyer immediately prior to
the transaction would not hold a majority of the voting stock or other voting
equity of the surviving entity immediately after completion of the transaction),
or sell, assign, lease or otherwise dispose of all or substantially all of its
assets, or recommend to its Shareholders a third-party tender offer for a
majority of its outstanding voting Shares; or (ii) acquire a business (whether
by merger, stock purchase or asset purchase) in a transaction that would result
in the issuance of a number of the Buyer’s voting Shares equal to or exceeding
thirty percent (30%) of the Buyer’s voting Shares outstanding after giving
effect to the proposed transaction; or (iii) appoint a new Chief Executive
Officer (any of the foregoing, a “Covered Transaction”), then the Board shall
establish a special committee of the Board pursuant to the By-Laws, which
committee shall consist of the Nominee (or if there is no Nominee serving on the
Board, the Observer), the Chairman of the Board, and the Chief Executive Officer
of the Buyer (the “Special Committee”). The Covered Transaction will require the
unanimous approval of all of the members of the Special Committee before it can
be submitted to the full Board for consideration; provided, however, that the
foregoing requirement shall be subject and subordinate to the fiduciary duties
of each Director and any other restrictions under applicable Law and the listing
standards of any exchange on which securities of the Buyer are then
listed.





SECTION
5.            Confidentiality.





5.1.  In
connection with the service of the Nominee on the Board and the attendance at
Board meetings by and the other rights of the Observer, the Seller, the Observer
and Affiliates of the Seller and its or their officers, directors, agents or
advisors (collectively, “Seller Parties”) will
obtain certain information from the Buyer and/or Affiliates of the Buyer and/or
its or their officers, directors, agents or advisors (collectively, “Buyer
Parties”).  As a condition to any Buyer Party’s furnishing any
Seller Party with such information, the Seller agrees that it shall, and shall
cause each other Seller Party to, treat as confidential and proprietary to the
Buyer and its Affiliates (as provided below) any information (whether written or
oral) which any Buyer Party furnishes to any Seller Party (including, without
limitation, account statements, financial statements and other financial,
operating, performance, cost, business, sales, customer, counterpart or other
information, and information with respect to any proposed acquisition,
disposition, offering or other transaction, relating to any Buyer Party)
(collectively, the “Confidential
Information”).


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5.2.  Seller
agrees that it shall, and shall cause each other Seller Party to (i) transmit
Confidential Information only to Seller Parties who need to know such
information for the purpose of evaluating the Seller’s investment in the Buyer
(the “Purpose”)
and who shall be advised by Seller of the confidentiality obligations of this
Section 5 and agree with Seller to be bound by the provisions hereof, (ii) keep
confidential, and not, except as hereinafter provided, without the prior written
consent of the Buyer, disclose in any manner whatsoever the Confidential
Information, in whole or in part, and (iii) not use the Confidential Information
in any way detrimental to the Buyer or for any purpose other than the
Purpose.  In any event, the Seller shall be responsible for any breach
of this agreement by any other Seller Party and agrees, at the Seller’s sole
expense, to take all reasonable measures (including but not limited to court
proceedings) to restrain all other Seller Parties from prohibited or
unauthorized disclosure or use of the Confidential Information.





5.3.  In the event
that any Seller Party is required by Law or governmental regulation (by oral
questions, interrogatories, requests for information or documents subpoena,
civil investigative demand or similar process) to disclose any Confidential
Information, the Seller will provide the Buyer with prompt notice of such
request(s) so that the Buyer may seek an appropriate protective order and/or
waive Seller’s compliance with the provisions of this Agreement and will
cooperate with the Buyer in protecting the confidential or proprietary nature of
the Confidential Information which must be so disclosed.  It is
further agreed that if, in the absence of a protective order or the receipt of a
waiver hereunder, any Seller Party is nonetheless, in the written opinion of the
Seller’s counsel, compelled to disclose any Confidential Information to any
governmental agency or tribunal or else stand liable for contempt or suffer
other censure or penalty, the Seller Party may disclose such limited information
to such agency or tribunal without liability hereunder, provided that the Seller
shall exercise its best efforts to obtain assurance from the recipient that
confidential treatment will be accorded such information.





5.4.  In addition,
the Seller hereby acknowledges that it is aware (and that other Seller Parties
who are furnished Confidential Information have been or will be advised) that
the United States securities
Laws prohibit any person who has material nonpublic information about a company
from purchasing or selling securities of such company.





5.5.  Upon
termination of this Agreement pursuant to Section 7 hereof, the Seller will (and
will cause the other Seller Parties to) promptly (a) deliver to the Buyer the
Confidential Information, with all copies thereof, and (b) destroy all internal
documents, databases and records containing Confidential Information (in
whatever format, written, recorded, electronic or other; and in such manner,
with respect to recorded and electronic information, that it shall be
permanently deleted and not recoverable) (except to the extent that Seller is
required by applicable Laws to retain such information, in which case it will
remain subject to the other provisions of this letter), and provide an officer’s
certificate that such destruction has occurred.


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5.6.  The term
“Confidential Information” does not include information which (i) becomes or has
been generally available to the public other than as a result of a disclosure by
any Seller Party, (ii) was available to a Seller Party on a non-confidential
basis prior to its disclosure to a Seller Party by a Buyer Party, or (iii)
becomes available to any Seller Party on a non-confidential basis from a source
other than a Buyer Party, provided, however, that such source is not, to any
Seller Party’s knowledge after due inquiry, bound by a confidentiality agreement
with any Buyer Party.





5.7.  The Seller
understands and agrees that, except as may otherwise be agreed in writing, (a)
no Buyer Party makes any representation or warranty as to the accuracy or
completeness of the Confidential Information and (b) no Buyer Party shall have
any liability to any Seller Party resulting from the use of the Confidential
Information by any Seller Party.





5.8.  Nothing
herein shall give any Seller Party any rights, title, license or interest
whatsoever in or to the Confidential Information (which shall remain at all
times the property of the Buyer or other Buyer Party).





5.9.  Nothing
herein shall be construed to limit or expand the rights, obligations and duties
(including, without limitation, fiduciary duties) of the Nominee in his or her
capacity as a Director, which shall in all cases be governed by and construed in
accordance with the Buyer’s articles of incorporation and By-Laws and the Nevada
Private Corporations Law and other applicable Laws.





SECTION
6. Indemnification and
Insurance.




6.1.  The Buyer
shall indemnify, defend and hold harmless the Nominee from and against costs,
expenses, liabilities, claims, judgments, damages and losses, including, without
limitation, all reasonable attorneys’ fees and expenses and the related cost of
any investigation and preparation, incurred in connection with any threatened,
pending or completed action or proceeding, whether civil, criminal,
administrative or investigative, arising out of or related to the fact that
Nominee is or was a director of the Buyer to the maximum extent that it
indemnifies its other Directors, whether pursuant to its by-laws, by contract or
both.




6.2.  The Buyer
shall maintain directors’ liability and other insurance covering the Nominee to
the maximum extent that it maintains such insurance coverage of its other
Directors.




SECTION
7.Termination.  This
Agreement will terminate when Seller is no longer entitled to name a Nominee for
election as a Director, as provided above, or unless sooner terminated by the
Seller in writing; provided, however, that notwithstanding any such termination,
the obligations of the Seller and the Observer under Section 5 shall continue
for a period of one year after such termination, and the provisions of Sections
10 and 17 shall survive indefinitely.





SECTION
8. Notices.  Any
notice provided for in this Agreement must be in writing and shall be
effectively given when given as provided in the Stock Purchase
Agreement.


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SECTION
9.           Severability.  If
any provision of this Agreement shall be determined to be illegal or
unenforceable by any court of law of competent jurisdiction the remaining
provisions shall be severable and enforceable in accordance with their
terms.





SECTION
10.         Governing Law;
Jurisdiction.  This Agreement shall be governed by and
construed in accordance with the Laws of the State of Nevada, without giving
effect to any conflict of laws principles thereof that would require the
application of the Laws of any jurisdiction other than the State of
Nevada.  Each of the parties hereto irrevocably and unconditionally
consents to the exclusive jurisdiction of the United States District Court for
the Southern District of New York sitting in the Borough of Manhattan in respect
of the interpretation and enforcement of the provisions of this
Agreement.  Each party further agrees that service of any process,
summons, notice or document by U.S. registered mail to such party’s respective
address set forth above shall be effective service of process for any Action
with respect to any matters to which it has submitted to jurisdiction in this
Section 10.  Each party irrevocably and unconditionally waives any
objection to the laying of venue of any Action arising out of this Agreement or
the transactions contemplated by this Agreement in the United States District
Court for the Southern District of New York sitting in the Borough of Manhattan,
and hereby further irrevocably and unconditionally waives and agrees not to
plead or claim in any such court that any such Action brought in any such court
has been brought in an inconvenient forum.  EACH PARTY HEREBY
IRREVOCABLY WAIVES ALL RIGHT TO TRIAL BY JURY IN ANY ACTION (WHETHER BASED ON
CONTRACT, TORT OR OTHERWISE) ARISING OUT OF OR RELATING TO THIS AGREEMENT OR THE
ACTIONS OF SUCH PARTY IN THE NEGOTIATION, ADMINISTRATION, PERFORMANCE AND
ENFORCEMENT HEREOF.





SECTION
11.         Assignment; Benefits of
Agreement.  Neither this Agreement nor any right, remedy,
obligation or liability arising hereunder or by reason hereof shall be
assignable (whether by operation of law or otherwise) by either Buyer or Seller,
and any attempted assignment contrary to the provisions of this Agreement shall
be null and void. This Agreement does not create, and shall not be construed as
creating, any rights enforceable by any other person who is not, or who does not
become, a party to this Agreement, except that each Buyer Party other than the
Buyer shall be an express third-party beneficiary of the provisions of Section
5.





SECTION
12.         Modification.  Neither
this Agreement nor any provision hereof can be amended, supplemented or
otherwise modified, except by an instrument in writing signed by both Parties
hereto, in which event such modification shall be binding upon both Parties
hereto in accordance with its terms.





SECTION
13.         Captions and References to
Sections.  The captions herein are inserted for convenience
only and shall not define, limit, extend or describe the scope of this Agreement
or affect the construction hereof. Sections mentioned by number only are the
respective sections of this Agreement. The words “hereof,” “hereto” and
“hereunder” and other words of like import refer to this Agreement as a whole
and not to any particular section or provision of this
Agreement.


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SECTION
14.         Entire
Agreement.  This Agreement and the Transaction Documents set
forth the entire understanding of the parties with respect to the subject matter
hereof.





SECTION
15.         Waiver.  Any
waiver by any party hereto of a breach of any provision of this Agreement shall
not operate as or be construed to be a waiver of any other breach of that
provision or of any breach of any other provision of this Agreement. The failure
of a party hereto to insist upon strict adherence to any term of this Agreement
on one or more occasions shall not be considered a waiver or deprive that party
of the right thereafter to insist upon strict adherence to that term or any
other term of this Agreement. Any waiver must be evidenced by an instrument in
writing signed by the party against whom the waiver is sought to be
enforced.





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





SECTION
17.         Interpretation.  Notwithstanding
any rule of law or custom to the contrary, neither this Agreement nor any other
agreement or document collateral to or otherwise relating to this Agreement
shall be interpreted or construed against any party merely by reason of the fact
that such agreement or document was prepared by or at the direction of such
party or that such party drafted or caused this Agreement to be
drafted.





SECTION
18.         Future
Cooperation.  Each party hereto shall cooperate and shall take
such further action and shall executed and deliver such further documents as may
be reasonably requested by any other party in order to carry out the provisions
and purposed of this Agreement.





SECTION
19.         Number and
Gender.  All terms and words used in this Agreement, regardless
of the number or gender in which they are used, shall be deemed to include any
other number and any other gender as the context may require.





[Signature
Page Follows]


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IN
WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date
first above written.





La
      Cortez Energy, Inc.By:Name:Title:Avante
      Petroleum SABy:Name:Title:





For
purposes of confirming their agreement to the provisions of Section 3.3
only:





Nadine
      SmithAndres
      Gutierrez


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