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                                                                     EXHIBIT 4.1



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                        BROOKFIELD PROPERTIES CORPORATION



                                SHARE OPTION PLAN


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   ESTABLISHED BY THE BOARD OF DIRECTORS OF BROOKFIELD PROPERTIES CORPORATION
                               ON NOVEMBER 7, 1990



                                FEBRUARY 5, 2004


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                        BROOKFIELD PROPERTIES CORPORATION

                                SHARE OPTION PLAN

SECTION 1:  GENERAL PROVISION

1.1  Purpose

     The purpose of the Share Option Plan (the "Plan") of Brookfield Properties
     Corporation (herein called the "Corporation") is to advance the interests
     of the Corporation by (i) providing Eligible Persons with additional
     incentive; (ii) encouraging stock ownership by such Eligible Persons; (iii)
     increasing their proprietary interest in the success of the Corporation;
     (iv) encouraging Eligible Persons to remain with the Corporation or its
     Subsidiaries; and (v) attracting new employees, officers and directors.

1.2  Administration

     (a)  The Plan shall be administered by the Board of Directors of the
          Corporation (the "Board").

     (b)  Subject to the limitations of the Plan, the Board shall have the
          authority: (i) to grant options to acquire common shares of the
          Corporation (the "Common Shares") to Eligible Persons; (ii) to
          determine the terms, limitations, restrictions and conditions upon
          such grants; (iii) to interpret the Plan and to adopt, amend and
          rescind such administrative guidelines and other rules and regulations
          relating to the Plan as it shall from time to time deem advisable; and
          (iv) to make all other determinations and to take all other actions in
          connection with the implementation and administration of the Plan as
          it may deem necessary or advisable. The Board's guidelines, rules,
          regulations, interpretations and determinations shall be conclusive
          and binding upon the Corporation and all other persons.

1.3  Interpretation

     For the purposes of the Plan, the following terms shall have the following
     meanings:

     (a)  "Eligible Persons" means officers or employees of the Corporation,
          officers or employees of any subsidiary, and non-management directors
          of the Corporation only in respect of options granted prior to
          February 4, 2004;

     (b)  "Options" means options to acquire Common Shares granted under the
          Plan;

     (c)  "Participants" means Eligible Persons to whom Options have been
          granted;

     (d)  "Subsidiary" means any company that is a subsidiary of the Corporation
          as defined in section 1(4) of the Securities Act (Ontario); and

     (e)  "Underlying Share" means a Common Share issuable upon the exercise of
          an Option.

     Words importing the singular number only shall include the plural and vice
     versa and words importing the masculine shall include the feminine.

     The Plan and all matters to which reference is made herein shall be
     governed by and interpreted in accordance with the laws of the Province of
     Ontario and the laws of Canada applicable therein.

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1.4  Shares Reserved

     (a)  All shares of the Corporation issued under the Plan shall be Common
          Shares in the capital stock of the Corporation. Options may be granted
          in respect of authorized and unissued Common Shares.

          The maximum number of Common Shares ("Specified Maximum") which may be
          reserved for issuance under the Plan shall be 9,000,000(1) Common
          Shares. The Specified Maximum is subject to adjustment in accordance
          with the provisions of the Plan.

          The aggregate number of Common Shares reserved for issuance to any one
          person under the Plan shall not exceed 5% of the outstanding Common
          Shares (on a non-diluted basis) less the aggregate number of Common
          Shares reserved for issuance to such person under any other share
          compensation arrangement (as defined under the applicable rules of the
          Toronto Stock Exchange (the "TSX Rules")) of the Corporation.

          Any Common Shares subject to an Option which has been granted under
          the Plan, which for any reason is cancelled or terminated without
          having been exercised, shall again be available for grants under the
          Plan. No fractional shares shall be issued, and the Board may
          determine the manner in which fractional share value shall be treated.

     (b)  In the event of any change in the outstanding Common Shares by reason
          of any stock dividend or split, recapitalization, merger,
          consolidation, combination or exchange of shares, or other corporate
          change, or in the event of any issue of rights pursuant to a
          shareholder rights plan or other similar plan the Board shall make,
          subject to the prior approval of the relevant stock exchanges,
          appropriate substitution or adjustment in (i) the number or kind of
          shares or other securities reserved for issuance pursuant to the Plan;
          and (ii) the number and kind of shares subject to unexercised Options
          theretofore granted and in the Exercise Price of such Options;
          provided, however, that no substitution or adjustment shall obligate
          the Corporation to issue or sell fractional shares. In the event of
          the reorganization of the Corporation or the amalgamation, merger or
          consolidation of the Corporation with another corporation, or the
          payment of a special or extraordinary dividend, the Board may make
          such provision for the protection of the rights of Participants as the
          Board in its discretion deems appropriate.

1.5  Non-Exclusivity

     Nothing contained herein shall prevent the Board from adopting other or
     additional compensation arrangements, subject to any required approval.

1.6  Amendment and Termination

     (a)  The Board may amend, suspend or terminate the Plan or any portion
          thereof at any time in accordance with applicable legislation, and
          subject to any required approval, including pre-clearance of such
          action by the Toronto Stock Exchange (the "TSX"). No amendment shall
          be made without shareholder approval which shall (i) increase (except
          in accordance with the provisions of the Plan) the Specified Maximum
          such that the aggregate of the Specified Maximum and the maximum
          number of Common Shares reserved for issuance pursuant to all of the
          Corporation's other "share compensation arrangements", as such term is
          defined under the TSX Rules could result, at any time, in the number
          of Common Shares reserved

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(1) The Specified Maximum was increased from 4,500,000 at the February 5, 2004
meeting of the board or directors; provided that such change is subject to the
approval of the shareholders.

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          for issuance under the Plan and all other "share compensation
          arrangements" of the Corporation exceeding 10% of the "outstanding
          issue", as such term is defined under the TSX Rules; or (ii)
          materially increase the benefits accruing to Participants. No such
          amendments, suspension or termination shall alter or impair any
          Options or any rights pursuant thereto granted previously to any
          Participant without the consent of such Participant. In the event of
          termination of the Plan, the provisions of the Plan and any
          administrative guidelines, and other rules and regulations adopted by
          the Board and in force at the time of the Plan shall continue in
          effect during such time as an Option or any rights pursuant thereto
          remain outstanding.

     (b)  With the consent of the Participant affected thereby and subject to
          pre-clearance by the TSX and regulatory approval, if any, the Board
          may amend or modify any outstanding Option provided that without
          shareholder approval no amendment shall be made which is equivalent to
          the establishment of a new Option, or which materially amends an
          Option held by an "insider", as such term is defined under the TSX
          Rules.

1.7  Compliance with Legislation

     The Board may postpone any exercise of any Option or the issue of any
     Underlying Shares pursuant to the Plan for such time as the Board in its
     discretion may deem necessary in order to permit the Corporation to effect
     or maintain registration of the Plan or the Common Shares issuable pursuant
     thereto under the securities laws of any applicable jurisdiction, or to
     determine that such shares and the Plan are exempt from such registration.
     The Corporation shall not be obligated by any provision of the Plan or
     grant thereunder to sell or issue Common Shares in violation of the law of
     any government having jurisdiction therein. In addition, the Corporation
     shall have no obligation to issue any Common Shares pursuant to the Plan
     unless such Common Shares shall have been duly listed, upon official notice
     of issuance, with a stock exchange on which such Common Shares are listed
     for trading.

SECTION 2:  OPTIONS

2.1  Grants

     Subject to the provisions of the Plan, the Board shall have the authority
     to determine the limitations, restrictions and conditions, if any, in
     addition to those set forth in Section 2.3 hereof, applicable to the
     exercise of an Option, including, without limitation, the nature and
     duration of the restrictions, if any, to be imposed upon the sale or other
     disposition of the Underlying Shares, and the nature of the events, if any,
     and the duration of the period in which any Participant's rights in respect
     of the Underlying Shares may be forfeited. An Eligible Person may receive
     Options on more than one occasion under the Plan and may receive separate
     Options on any one occasion.

2.2  Option Exercise Price

     The Board shall establish the exercise price ("Exercise Price") of each
     Option at the time such Option is granted, which shall equal the closing
     price of a Common Share on the TSX, for Canadian Participants, or the New
     York Stock Exchange, for U.S. Participants, on the last trading day
     preceding the date of grant of such Option, and shall, in all cases, be not
     less than such amount required by applicable regulatory authorities from
     time to time.

     The Exercise Price shall be subject to adjustment in accordance with the
     provisions of Section 1.4(b) hereof.


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2.3  Exercise of Options

     (a)  An Option may be exercised at the election of a Participant by the
          purchase of the Underlying Shares at the Exercise Price specified for
          such Option.

     (b)  Options shall not be exercisable later than 10 years after the date of
          grant.

     (c)  The Board may determine when any Option shall become vested and
          exercisable and may determine that the Option shall be vested and
          exercisable in installments.

     (d)  Except as otherwise determined by the Board: (i) in the event that a
          Participant ceases to be an Eligible Person for any reason other than
          death, retirement or disability, each of the Options held by the
          Participants shall cease to be exercisable after the date of
          termination of employment; (ii) in the event of termination of
          employment or ceasing to be a director as a result of retirement, all
          of the Participant's Options shall continue in force notwithstanding
          the termination of his or her employment or ceasing to be a director;
          and (iii) in the event of death, the legal representatives of a
          Participant may exercise the Participant's vested Options within six
          months after the date of the Participant's death to the extent such
          Options were by their terms vested and exercisable prior to the
          Participant's death or within the period of six months following his
          the Participant's death; but for greater certainty no Option shall be
          exercisable after its stated termination date.

     (e)  Each Option shall be confirmed by an agreement (an "Option Agreement")
          executed by the Corporation and by the Participant.

     (f)  If, as and when any Common Shares have been duly issued upon the
          exercise of an Option and in accordance with the terms of such Option
          and the Plan and any regulations made hereunder, such Underlying
          Shares shall be conclusively deemed allotted as fully paid and
          non-assessable shares of the Corporation.

     (g)  Options granted pursuant to the Plan may be assigned by the
          Participant to: (i) the Participant's spouse (as defined in the Income
          Tax Act (Canada)); (ii) a trust, the trustee of which is the
          Participant and the beneficiaries of which are one or more of the
          Participant and the Participant's spouse, minor children or minor
          grandchildren; or (iii) a corporation controlled by the Participant
          (within the meaning of the Canada Business Corporations Act
          (Ontario)), the shares of which are held directly or indirectly by the
          Participant, the Participant's spouse, minor children or minor
          grandchildren. Notwithstanding a permitted assignment under the Plan,
          an assigned Option shall be deemed, for the purposes of compliance
          with the policies of the relevant stock exchanges, to be held by the
          Participant to whom the Option was initially granted.

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SECTION 3.  APPROVAL

3.1  APPROVAL

     The Plan was approved by the directors of the Corporation on November 7,
     1990.

3.2  AMENDMENT

     The Plan was amended by the directors of the Corporation on February 9,
     1998. Shareholder approval of the February 9, 1998 amendment was given at
     the annual and special meeting of the Corporation held on April 29, 1998.

     The Plan was amended and restated by the directors of the Corporation on
     February 5, 2004 to (i) eliminate the market growth feature, (ii) to delete
     directors of the Corporation as eligible persons under the Plan except for
     options granted to non-management directors prior to that date, (iii) to
     delete references to the pension plan and (iv) subject to approval of the
     shareholders of the Corporation, to increase the Specified Maximum to
     9,000,000.


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                       REGULATIONS UNDER SHARE OPTION PLAN

1.   In these regulations, words defined in the Plan and not otherwise defined
     herein shall have the same meaning as set forth in the Plan.

          (a) "year" with respect to any Option granted under the Plan means the
          period of 12 months commencing on the date of the granting of such
          Option or on any anniversary thereof.

2.   No Option shall be granted under the Plan unless recommended by the Human
     Resources and Compensation Committee of the Board.

3.   Not less than 100 Common Shares may be acquired at any one time except
     where the remainder totals less than 100.

4.   In the event that the legal representatives of a Participant who has died
     exercises the Participant's Option in accordance with the terms of the
     Plan, the Corporation shall have no obligation to issue the Common Shares
     until evidence satisfactory to the Corporation has been provided by such
     legal representatives that such legal representatives are entitled to
     acquire the Common Shares under the Plan.

5.   Common Shares duly acquired under the terms of an Option shall be
     registered in the name of the Participant and a share certificate
     representing the number of such Common Shares shall be issued in the name
     of the Participant, his or her legal representatives or as he, she or they
     may direct.


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