EXHIBIT 10.6 SIXTH AMENDED AND RESTATED AGREEMENT OF LIMITED PARTNERSHIP OF HINES-SUMISEI U.S. CORE OFFICE FUND, L.P.

EXHIBIT 10.6

SIXTH AMENDED AND RESTATED

AGREEMENT OF LIMITED PARTNERSHIP

OF

HINES-SUMISEI U.S. CORE OFFICE FUND, L.P.

May 9, 2005

TABLE OF CONTENTS

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List of Schedules:

List of Exhibits:

Exhibit A            Property Services Agreement Form

iv

SIXTH AMENDED AND RESTATED

AGREEMENT OF LIMITED PARTNERSHIP

OF

HINES-SUMISEI U.S. CORE OFFICE FUND, L.P.

          This SIXTH AMENDED AND RESTATED AGREEMENT OF LIMITED PARTNERSHIP OF HINES-SUMISEI U.S. CORE OFFICE FUND, L.P., a Delaware limited partnership (together with its successors, the “ Partnership ”), is entered into as of May 9, 2005, by and among Hines US Core Office Capital LLC, a Delaware limited liability company, as the Managing General Partner, Hines REIT Properties, L.P., a Delaware limited partnership, as the Non-Managing General Partner, and the Persons identified as Limited Partners on Schedule 2.1, as Limited Partners. Capitalized terms used and not defined in the following recitals are used as defined in Section 1.1 below.

Recitals

          WHEREAS, the Managing General Partner and the Hines Limited Partner entered into the Agreement of Limited Partnership of the Partnership on August 19, 2003 (the “ Original Agreement ”),

          WHEREAS, the Original Agreement was amended and restated as provided in the Amended and Restated Agreement of Limited Partnership of the Partnership, dated August 28, 2003 (the “ First Restated Agreement ”);

          WHEREAS, the First Restated Agreement was amended and restated as provided in the Second Amended and Restated Agreement of Limited Partnership of the Partnership, dated April 1, 2004 (the “ Second Restated Agreement ”);

          WHEREAS, the Second Restated Agreement was amended and restated as provided in the Third Amended and Restated Agreement of Limited Partnership of the Partnership, dated April 23, 2004 (the “ Third Restated Agreement ”);

          WHEREAS, the Third Restated Agreement was amended and restated as provided in the Fourth Amended and Restated Agreement of Limited Partnership of the Partnership, dated August 11, 2004 (the “ Fourth Restated Agreement ”);

          WHEREAS, the Fourth Restated Agreement was amended and restated as provided in the Fifth Amended and Restated Agreement of Limited Partnership of the Partnership, dated November 23, 2004 (the “ Fifth Restated Agreement ”); and

          WHEREAS, the Managing General Partner has requested that the Fifth Restated Agreement be amended and restated as provided herein, and the Non-Managing General Partner and the Limited Partners have consented to the amendment and restatement of the Fifth Restated Agreement as provided herein in accordance with the applicable provisions of the Fifth Restated Agreement;

          NOW, THEREFORE, in consideration of the premises, the terms and conditions set forth herein, the mutual benefits to be gained by the performance thereof and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Fifth Restated Agreement is hereby amended and restated in its entirety as follows:

ARTICLE I

     SECTION 1.1 Definitions . As used in this Agreement, the terms set forth below have the meanings indicated.

          “ Act ”: The Delaware Revised Uniform Limited Partnership Act, as amended from time to time, and any successor statute.

          “ Acquisition Fee ”: As defined in Section 7.3(a).

          “ Adjusted Capital Account ”: At any time, the then balance in the Capital Account of a Partner, after giving effect to the following adjustments:

     (i) add to such Capital Account any amounts that such Partner is obligated to restore under any provision of this Agreement or such Partners’ Subscription Agreement or is deemed obligated to restore as described in the penultimate sentences of Regulations Section 1.704-2(g)(1) and Regulations Section 1.704-2(i)(5), or any successor provisions; and

     (ii) subtract from such Capital Account the items described in Regulations Sections 1.704-1(b)(2)(ii)(d)(4), (5) and (6).

          “ Adjusted Capital Account Deficit ”: With respect to any Partner, the deficit balance, if any, in that Partner’s Adjusted Capital Account.

          “ Advisory Agreement ”: The Amended and Restated Advisory Agreement, dated as of April 1, 2004, by and among the Partnership, the Managing General Partner, SLR and such other Fund Entities as may become party thereto as contemplated by Section 5.7.

          “ Advisory Committee ”: As defined in Section 5.4(a).

          “ Affiliate ”: With respect to any Person, a Person which, directly or indirectly, Controls, is Controlled by or is under common Control with such Person. Notwithstanding the foregoing, the Non-Managing General Partner and Affiliates of the Non-Managing General Partner that are Controlled by the Non-Managing General Partner or its general partner shall be deemed not to be Affiliates of the Managing General Partner, Hines or the Partnership, and the Managing General Partner, Hines and their respective Affiliates shall be deemed not to be Affiliates of the Non-Managing General Partner or any of its Affiliates that are Controlled by the Non-Managing General Partner or it general partner.

          “ Aggregate Debt Limit ”: As defined in Section 3.6(a)(ii)(A).

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          “ Agreement ”: This Sixth Amended and Restated Agreement of Limited Partnership of the Partnership, together with all Schedules and Exhibits hereto, dated as of the date hereof and as each may be amended from time to time.

          “ Applicable Percentage ”: As defined in Section 5.9(d)(i).

          “ Appraiser ”: As defined in Section 5.9(b).

          “ Approved Agreements ”: The agreements listed on Schedule 2.7 and any agreement that the Partnership is obligated or permitted to enter into pursuant to any such agreement.

          “ Asset Management Fee ”: As defined in Section 7.2(a).

          “ Asset Management Fee Base ”: As defined in Section 7.2(a).

          “ Business Day ”: Any day other than a Saturday or Sunday, that is neither a legal holiday nor a day on which banking institutions in New York City are authorized or required by law, regulation or executive order to close.

          “ Capital Account ”: As defined in Section 8.1.

          “ Capital Call Notice ”: As defined in Section 3.2(a).

          “ Capital Calls ”: As defined in Section 3.2(a).

          “ Capital Cash Flow ”: As defined in Section 9.2.

          “ Capital Commitment ”: As defined in Section 3.2(a).

          “ Capital Contribution ”: With respect to any Partner, any contribution to the capital of the Partnership by such Partner in accordance with this Agreement.

          “ Capital Transaction Gain or Loss ”: Any Profits or Losses described in paragraphs (iii), (iv) and (vi) of the definition of Profits and Losses contained in this Section 1.1.

          “ Cash Needs ”: Any cash needs or requirements of whatever kind of the Partnership for which sufficient funds are not available from investment income or from reserves held by the Partnership, including (i) funds required to be contributed by the Partnership to any Fund Entity for the purpose of acquiring Investments or paying costs and expenses related thereto, (ii) Organizational Expenses and any other Partnership Expenses, and (iii) the cost of redeeming Partnership Interests in accordance with this Agreement.

          “ CBD ”: As defined in Section 5.2(b)(i).

          “ Certificate ”: As defined in Section 2.1.

          “ Class A Major Investor ”: An Investor with an aggregate Capital Commitment of at least $300 million.

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          “ Class B Major Investor ”: An Investor with an aggregate Capital Commitment of at least $150 million, but less than $300 million.

          “ Class C Major Investor ”: An Investor with an aggregate Capital Commitment of at least $75 million, but less than $150 million.

          “ Class D Major Investor ”: An Investor with an aggregate Capital Commitment of at least $50 million, but less than $75 million.

          “ Class N Partnership Units ”: As defined in Section 3.5(a).

          “ Code ”: The Internal Revenue Code of 1986, as amended as of the date hereof and as the same may be amended from time to time, and any successor statute.

          “ Committed Capital ”: (i) As to any Partner, the sum of (A) the Partnership’s total equity capital multiplied by a fraction, the numerator of which is the total number of Units held by such Partner and the denominator of which is the total number of Units outstanding plus, prior to the termination of the Investment Period, (B) the Unfunded Commitment of such Partner, (ii) as to any Fund Investor, the Fund’s total equity capital multiplied by the percentage of the Fund’s total equity capital attributed to the equity interests held by such Fund Investor in the Partnership and any Operating Company plus the amount of any additional capital that such Fund Investor is obligated to contribute, but has not yet contributed, to the Partnership or any Operating Company, (iii) as to the Partnership, the aggregate of the Committed Capital of all Partners and (iv) as to the Fund, the aggregate of the Committed Capital of all Fund Investors.

          “ Constituent Documents ”: With respect to any Entity, its constituent, governing or organizational documents, including (a) in the case of a limited partnership, its certificate of limited partnership and its limited partnership agreement, (b) in the case of a limited liability company, its articles or certificate of formation and its operating agreement or limited liability company agreement, (c) in the case of a corporation, its articles or certificate of incorporation and its bylaws and (d) in the case of a trust, its declaration of trust and bylaws.

          “ Control ”: With respect to any Person, the possession, directly or indirectly, of the power to direct or cause the direction of the management and policies of such Person, whether through the ownership of voting securities, by contract or otherwise.

          “ Contributing Partner ”: As defined in Section 3.7(a).

          “ Current Market Value ”: As defined in Section 5.9(c)(i).

          “ Current Participation Interest Value ”: As defined in Section 5.9(c)(iii).

          “ Current Total Equity Value ”: As defined in Section 5.9(c)(ii).

          “ Current Unit Value ”: As defined in Section 5.9(c)(iv).

          “ Defaulting Partner ”: As defined in Section 10.8(b).

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          “ Default Rate ”: The rate of interest per annum equal to the lesser of (i) the Prime Rate plus four percent and (ii) the highest rate permitted by applicable law.

          “ Depreciation ”: For any Fiscal Year or portion thereof, an amount equal to the depreciation, amortization or other cost recovery deduction allowable with respect to an asset for such period for federal income tax purposes, except that if the Gross Asset Value of an asset differs from its adjusted basis for federal income tax purposes at the beginning of such period, Depreciation shall be an amount that bears the same relationship to such beginning Gross Asset Value as the depreciation, amortization or cost recovery deduction in such period for federal income tax purposes bears to the beginning adjusted tax basis; provided, however , that if the adjusted basis for federal income tax purposes of an asset at the beginning of such period is zero, Depreciation shall be determined with reference to such beginning Gross Asset Value using any reasonable method selected by the Managing General Partner.

          “ Entity ”: Any corporation, partnership, limited partnership, limited liability company, trust, association, joint stock company or other legal entity.

          “ ERISA ”: The Employee Retirement Income Security Act of 1974, as amended.

          “ Event of Withdrawal ”: As defined in Section 12.1(a).

          “ Fees ”: Asset Management Fees and Acquisition Fees.

          “ Feeder Entity ”: As defined in Section 2.10.

          “ Fifth Restated Agreement ”: As defined in the Recitals of this Agreement.

          “ Finding of Cause ”: As defined in Section 10.2(a).

          “ First Restated Agreement ”: As defined in the Recitals of this Agreement.

          “ Fiscal Quarter ”: As defined in Section 2.8.

          “ Fiscal Year ”: As defined in Section 2.8.

          “ Fourth Restated Agreement ”: As defined in the Recitals of this Agreement.

          “ Fund ”: As defined in Section 5.1(a).

          “ Fund Entity ”: As defined in Section 5.1(a).

          “ Fund Investor ”: As defined in Section 5.1(a).

          “ Fund Vote ”: As defined in Section 11.6(g).

          “ Funded Commitment ”: As defined in Section 3.2(a).

          “ GAAP ”: Generally accepted accounting principles in the United States, consistently applied.

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          “ GM Investor Rights Agreement ”: The Amended and Restated Investor Rights Agreement, dated as of December 23, 2003, among Hines, the Partnership, NY Trust, General Motors Investment Management Corporation and the other Persons party thereto.

          “ Gross Asset Value ”: With respect to any Partnership asset, the asset’s adjusted basis for federal income tax purposes, except as follows:

     (i) The initial Gross Asset Value of any asset contributed by a Partner to the Partnership shall be the gross fair market value of such asset, as determined by the Managing General Partner and agreed to by the Contributing Partner;

     (ii) The Gross Asset Value of all Partnership assets shall be adjusted to equal their respective gross fair market values, as determined by the Managing General Partner (which determination shall be based upon, and consistent with, the most recent Current Market Values), as of the following times: (a) the acquisition of an additional interest in the Partnership by any new or existing Partner in exchange for more than a de minimis Capital Contribution; (b) the distribution by the Partnership to a Partner of more than a de minimis amount of Partnership property as consideration for an interest in the Partnership; (c) the liquidation of the Partnership within the meaning of Regulations Section 1.704-1(b)(2)(ii)(g); and (d) upon the occurrence of any other event for which such an adjustment is permitted under the Regulations; provided, however, that adjustments pursuant to clauses (a), (b) and (d) above shall be made only if the Managing General Partner reasonably determines that such adjustments are necessary or appropriate to reflect the relative economic interests of the Partners in the Partnership;

     (iii) The Gross Asset Value of any Partnership asset distributed to any Partner shall be adjusted to equal the gross fair market value of such asset on the date of distribution as determined by the Managing General Partner (which determination shall be based upon, and consistent with, the most recent Current Market Values); and

     (iv) The Gross Asset Value of Partnership assets shall be increased (or decreased) to reflect any adjustments to the adjusted basis of such assets pursuant to Code Section 734(b) or Code Section 743(b), but only to the extent that such adjustments are taken into account in determining Capital Accounts pursuant to Regulations Section 1.704-1(b)(2)(iv)(m) and paragraph (vi) of the definition of Profits and Losses and Section 8.6(g); provided, however, that Gross Asset Value shall not be adjusted pursuant to this paragraph (iv) to the extent the Managing General Partner determines that an adjustment pursuant to paragraph (ii) above is necessary or appropriate in connection with a transaction that would otherwise result in an adjustment pursuant to this paragraph (iv).

          If the Gross Asset Value of an asset has been determined or adjusted pursuant to paragraphs (i), (ii) or (iv) above, such Gross Asset Value shall thereafter be adjusted by the

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Depreciation taken into account with respect to such asset for purposes of computing Profits and Losses.

          “ Hines ”: Hines Interests Limited Partnership, a Delaware limited partnership, and its successors.

          “ Hines Bridge Equity ”: As defined in Section 3.10.

          “ Hines Capital Requirement ”: As defined in Section 3.11

          “ Hines Controlled Entity ”: Any partnership, limited liability company, corporation, trust or other entity which is, directly or indirectly, Controlled by (a) Hines, (b) HREH and/or (c) Jeffrey C. Hines and/or Gerald D. Hines or, in the event of the death or disability of Jeffrey C. Hines and/or Gerald D. Hines, the heirs, legal representatives or estates of either or both of them.

          “ Hines Group ”: (a) Jeffrey C. Hines and/or Gerald D. Hines, their parents, brothers and sisters, and the respective spouses, children or grandchildren of any of the foregoing (including children or grandchildren by adoption), and (b) any current or former employee of Hines.

          “ Hines Investment Allocation Committee ”: As defined on Schedule 4.4 .

          “ Hines Limited Partner ”: Hines US Core Office Capital Associates II Limited Partnership, a Texas limited partnership, and its successors.

          “ HREH ”: Hines Real Estate Holdings Limited Partnership, a Texas limited partnership.

          “ Indebtedness ”: With respect to any Person, (i) any indebtedness for borrowed money evidenced by a note payable by such Person, (ii) any obligation to pay money secured by any mortgage, pledge, security interest, encumbrance, lien or charge of any kind existing on any asset owned or held by such Person, whether or not such Person has assumed or become personally liable for the obligations secured thereby, and (iii) any guaranty by such Person of the Indebtedness (as defined in clause (i) and (ii) of this definition) of another Person; provided that “Indebtedness” with respect to any Person shall not include obligations in respect of any accounts payable that are incurred in the ordinary course of such Person’s business (or guarantees by such Person of such obligations of another Person) and are not delinquent or are being contested in good faith by appropriate proceedings.

          “ Indemnified Person ”: As defined in Section 6.1.

          “ Initial Asset Group ”: The three office properties acquired from Sumitomo by NY Trust and 600 Lexington.

          “ Initial Investment Period ”: As defined in Section 3.4.

          “ Initial Offering Period ”: As defined in Section 3.3.

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          “ Initial Offering Price ”: $1,000.00 per Unit.

          “ Investment Advisor ”: An Affiliate of Hines or SLR that provides advisory services to the Managing General Partner pursuant to the Advisory Agreement as contemplated by Section 5.7.

          “ Investment Company Act ”: The Investment Company Act of 1940, as amended as of the date hereof and as the same may be amended from time to time, and any successor statute.

          “ Investment Guidelines ”: As defined in Section 5.2(b).

          “ Investments ”: As defined in Section 5.2(a).

          “ Investor ”: As defined in Section 3.2(a).

          “ Limited Partner ”: Any Person now or hereafter admitted as a limited partner in accordance with the terms of this Agreement. The Limited Partners as of the date hereof are the Persons identified as such on Schedule 2.1 .

          “ Liquidating Event ”: As defined in Section 12.1.

          “ Liquidating Redemption ”: As defined in Section 3.8 and, as the context requires, as defined in the corresponding provisions of the Constituent Documents of US Core Trust and US Core Properties.

          “ LP Vote ”: As defined in Section 11.6(g).

          “ Major Investor ”: An Investor with a Capital Commitment of at least $50 million.

          “ Majority Fund Vote ”: As defined in Section 11.7.

          “ Majority LP Vote ”: As defined in Section 11.6(g).

          “ Majority Partner Vote ”: As defined in Section 11.6(g).

          “ Management Board ”: As defined in Section 5.3(a).

          “ Management Team ”: As defined in Section 5.5.

          “ Managing General Partner ”: Hines US Core Office Capital LLC, a Delaware limited liability company, and its successors, and any Person hereafter admitted as a general partner designated the Managing General Partner of the Partnership in accordance with the terms of this Agreement.

          “ Managing General Partner Expenses ”: As defined in Section 7.1.

          “ Moody’s ”: Moody’s Investor Services, Inc.

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          “ Non-Managing General Partner ”: As defined in Section 5.11(a).

          “ NOP ”: National Office Partners Limited Partnership, a limited partnership formed by the State of California Public Employees’ Retirement System and an Affiliate of Hines.

          “ Notice of Redemption ”: As defined in Section 3.8 and, as the context requires, as defined in the corresponding provisions of the Constituent Documents of US Core Trust and US Core Properties.

          “ NY Trust ”: Hines-Sumisei NY Core Office Trust, a Maryland real estate investment trust, and its successors.

          “ NY Trust II ”: Hines-Sumisei NY Core Office Trust II, a Maryland real estate investment trust, and its successors.

          “ Operating Company ”: NY Trust, NY Trust II, US Core Trust, US Core Properties, any successor to any of the foregoing, and any Entity hereafter designated an “Operating Company” by the Managing General Partner, subject to the provisions of Section 5.1.

          “ Operating Company Expenses ”: As defined in Section 7.5(a).

          “ Operating Cash Flow ”: As defined in Section 9.1.

          “ Organization Agreement ”: The Amended and Restated Organization Agreement, dated as of December 23, 2003, among General Motors Investment Management Corporation, a New York corporation, certain institutional investors advised thereby, Hines Interests Limited Partnership, a Delaware limited partnership, Hines US Core Office Capital Associates III Limited Partnership, a Texas limited partnership, Hines-Sumisei U.S. Core Office Fund, L.P., a Delaware limited partnership and Hines-Sumisei NY Core Office Trust, a Maryland real estate investment trust.

          “ Organizational Expenses ” As defined in Section 7.6.

          “ Original Agreement ”: As defined in the Recitals of this Agreement.

          “ Owner ”: As defined in the Property Services Agreement.

          “ Participation Interest ”: As defined in Section 3.7(c)(i).

          “ Partner Nonrecourse Debt ”: As defined in Regulations Section 1.704-2(b)(4).

          “ Partner Nonrecourse Debt Minimum Gain ”: As defined in Regulations Section 1.704-2(i).

          “ Partner Nonrecourse Deductions ”: As defined in Regulations Section 1.704-2(i).

          “ Partner Vote ”: As defined in Section 11.6(g).

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          “ Partners ”: Collectively, the Managing General Partner, the Non-Managing General Partner and the Limited Partners, and any additional or successor partners of the Partnership admitted to the Partnership in accordance with the terms of this Agreement. References to a Partner shall be to any one of the Partners.

          “ Partnership ”: As defined in the Preamble to this Agreement.

          “ Partnership Auditor ”: As defined in Section 11.2.

          “ Partnership Expenses ”: As defined in Section 7.4(a).

          “ Partnership Interest ”: The ownership interest of a Partner in the Partnership at any particular time, including the right of such Partner to any and all benefits to which such Partner may be entitled as provided in this Agreement, and to the extent not inconsistent with this Agreement, under the Act, together with the obligations of such Partner to comply with all of the terms and provisions of this Agreement and the Act.

          “ Partnership Minimum Gain ”: As defined in Regulations Sections 1.704-2(b)(2) and 1.704-2(d).

          “ Partnership Unit ” or “ Unit ”: A unit of Partnership Interest having the rights, privileges and restrictions prescribed therefor by the terms of this Agreement.

          “ Payment Date ”: As defined in Section 3.2(b).

          “ Percentage Interest ”: With respect to each Partner (i) for each Fiscal Quarter ending prior to the termination of the Initial Investment Period, a percentage equal to the number of Partnership Units then owned by such Partner, divided by the number of Partnership Units then outstanding, and (ii) for each Fiscal Quarter ending after termination of the Initial Investment Period, a percentage determined for each Partner as of each Quarterly Payment Date in the following manner:

          (a) End of Quarter Calculation of Percentage Interest Attributable to Participation Interests . As of each Quarterly Payment Date, each of Hines and SLR shall have a Percentage Interest in respect of its Participation Interest equal to the sum of:

     (i) (A) the Percentage Interest attributable to such Participation Interest as of the end of the immediately preceding Fiscal Quarter (which shall be 0% in the case of each Fiscal Quarter beginning prior to the termination of the Initial Investment Period), adjusted as provided in clause (c) below for Partnership Units issued during the Fiscal Quarter just ended; plus

     (ii) its AM Sharing Percentage (as defined below) of a fraction (A) whose numerator is 0.03125% of the Unrecovered Capital of SLR, plus 0.09375% of the aggregate Unrecovered Capital of all Class A Major Investors, plus 0.10625% of the aggregate Unrecovered Capital of all Class B Major Investors, plus 0.1125% of the aggregate Unrecovered Capital of all Class C Major Investors, plus 0.11875% of the aggregate Unrecovered Capital of all Class D

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Major Investors, plus 0.125% of the aggregate Unrecovered Capital of all Unaffiliated Limited Partners that are not Major Investors, each determined as of the end of the current Fiscal Quarter, and (B) whose denominator is the Current Total Equity Value of the Partnership as of the end of the current quarter; plus

     (iii) (A) its AQ Sharing Percentage (as defined below), multiplied by (B) the lesser of (x) the Total Property Base for the Fiscal Quarter just ended or (y) the Total Capital Base for the Fiscal Quarter just ended, divided by (C) the Current Total Equity Value of the Partnership as of the end of the Fiscal Quarter just ended.

          (b) When Change to Participation Interest Becomes Effective . The Percentage Interest determined under clause (a) as of the end of a particular Fiscal Quarter shall become effective as of the beginning of the immediately following Fiscal Quarter.

          (c) Adjustment of Percentage Interests Attributable to Participation Interest Following Issuance or Redemption of Partnership Units . Immediately after the issuance or redemption by the Partnership of any Partnership Units, the Percentage Interest attributable to the Participation Interest shall be adjusted so that it equals (i) the Percentage Interest attributable to the Participation Interest immediately prior to the issuance or redemption of such Partnership Units, multiplied by (ii) a fraction whose numerator is (A) the number of Outstanding Unit Equivalents immediately prior to the issuance or redemption of such Partnership Units and whose denominator equals (B) the number of Outstanding Unit Equivalents (as defined below) immediately prior to the issuance or redemption of such Partnership, plus the number of Partnership Units then being issued, or minus the number of Partnership Units then being redeemed, as the case may be.

          (d) Calculation of Percentage Interests of Partners’ Holding Partnership Units . As of each Quarterly Payment Date, each Partner holding Partnership Units shall have a Percentage Interest in respect of such Partnership Units equal to (i) 100%, minus the sum of the Percentage Interests attributable to the Participation Interests determined pursuant to clauses (a)

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and (c) above, multiplied by (ii) a fraction whose numerator is the number of Partnership Units then owned by such Partner and whose denominator is the total number of Partnership Units outstanding.

          (e) Calculation of Total Percentage Interests of Hines and SLR . The total Percentage Interest of Hines and SLR, as the case may be, shall equal such person’s Percentage Interest in respect of its Participation Interest (determined under clauses (a) and (c) above), plus such person’s Percentage Interest in respect of its Partnership Units (determined under clause (d) above).

          “ Person ”: An individual, corporation, partnership, limited liability company, estate, trust, association, joint stock company or other legal entity, or a group as that term is used for purposes of Section 13(d)(3) of the Securities Exchange Act of 1934, as amended.

          “ President ”: As defined in Section 5.5.

          “ Prime Rate ”: The rate of interest per annum announced from time to time by JPMorgan Chase Bank, or its successor, at its principal office in New York City as its prime rate.

          “ Priority Redemptions ”: As defined in Section 3.9.

          “ Priority Redemption Right ”: As defined in Section 3.9.

          “ Private Placement PTP Exemption ”: The exemption from publicly traded partnership status provided in Regulation Section 1.7704-1(h) (which generally applies if (i) all interests in a partnership are issued in a transaction or series of transactions that are not required to be registered under the Securities Act and (ii) the partnership does not have more than 100 partners at any time during taxable year of the partnership).

          “ Private Transfer ”: Any of the following:

     (i) transfers in which the basis of the Partnership Interest in the hands of the transferee is determined, in whole or in part, by reference to its basis in the hands of the transferor or is determined under Code Section 732;

     (ii) transfers at death, including transfers from an estate or testamentary trust;

     (iii) transfers between members of a family;

     (iv) transfers involving the issuance of interests by (or on behalf of) the Partnership in exchange for cash, property, or services;

     (v) transfers involving distributions from a qualified retirement plan or an individual retirement account;

     (vi) the transfer by a Partner and any related persons (within the meaning of Code Section 267(b) or 707(b)(1)) in one or more transactions during

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any thirty calendar day period of Partnership Interests representing in the aggregate more than 2 percent of the total interests in Partnership capital or profits;

     (vii) transfers by one or more Partners of interests representing in the aggregate 50 percent or more of the total interests in Partnership capital and profits in one transaction or a series of related transactions; and

     (viii) transfers not recognized by the Partnership within the meaning of Regulation Section 1.7704-1(d)(2) (i.e., the Partnership neither admits the transferee as a partner nor recognizes any rights of the transferee as a partner).

          “ Profits ” and “ Losses ”: For each Fiscal Year or portion thereof, an amount equal to the Partnership’s items of taxable income or loss for such year or period, determined by the Managing General Partner in accordance with Code Section 703(a) with the following adjustments:

     (i) any income which is exempt from federal income tax and not otherwise taken into account in computing Profits or Losses shall be added to taxable income or loss;

     (ii) any expenditures of the Partnership described in Code Section 705(a)(2)(B) or treated as Code Section 705(a)(2)(B) expenditures under Regulations Section 1.704-1(b)(2)(iv)(i) and not otherwise taken into account in computing Profits or Losses, will be subtracted from taxable income or loss;

     (iii) in the event that the Gross Asset Value of any Partnership asset is adjusted pursuant to the definition of Gross Asset Value contained in this Article I, the amount of such adjustment shall be taken into account as gain or loss from the disposition of such asset for purposes of computing Profits and Losses;

     (iv) gain or loss resulting from any disposition of Partnership assets with respect to which gain or loss is recognized for federal income tax purposes shall be computed by reference to the Gross Asset Value of the property disposed of, notwithstanding that the adjusted tax basis of such property differs from its Gross Asset Value;

     (v) in lieu of the depreciation, amortization and other cost recovery deductions taken into account in computing such taxable income or loss, there shall be taken into account Depreciation for such Fiscal Year or other period;

     (vi) to the extent an adjustment to the adjusted tax basis of any Partnership asset pursuant to Code Section 734(b) or Code Section 743(b) is required pursuant to Regulations Section 1.704-1(b)(2)(iv)(m)(4) to be taken into account in determining Capital Accounts as a result of a distribution other than in complete liquidation of a Partner’s Partnership Interest, or is required pursuant to the last sentence of Regulations Section 1.704-1(b)(2)(iv)(m)(2) to be taken into account in determining Capital Accounts the amount of such adjustment shall be

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treated as an item of gain (if the adjustment increases the basis of the asset) or loss (if the adjustment decreases the basis of the asset) from the disposition of the asset and shall be taken into account for purposes of computing Profits or Losses; and

     (vii) any items specially allocated pursuant to Section 8.6 or Section 8.7 shall not be considered in determining Profits or Losses.

          “ Property ”: As defined in Section 5.2(a).

          “ Property Manager ”: As defined in Section 5.8.

          “ Property Services Agreement ”: As defined in Section 5.8.

          “ Property Services Agreement Form ”: As defined in Section 5.8.

          “ Quarterly Payment Date ”: The first Business Day following the end of each Fiscal Quarter.

          “ Redeeming Partner ”: As defined in Section 3.8.

          “ Redemption Right ”: As defined in Section 3.8.

          “ Regulations ”: The Income Tax Regulations, including Temporary Regulations, promulgated under the Code, as such regulations may be amended from time to time (including corresponding provisions of succeeding regulations).

          “ Regulatory Allocations ”: As defined in Section 8.7.

          “ REIT ”: A “real estate investment trust” as defined in Section 856 of the Code and applicable Regulations.

          “ REIT Election Effective Date ”: As defined in Section 2.11.

          “ Required Vote ”: As defined in Section 13.3(a).

          “ S&P ”: Standard & Poor’s, a division of The McGraw-Hill Companies, Inc.

          “ Second Restated Agreement ”: As defined in the Recitals of this Agreement.

          “ Securities Act ”: The Securities Act of 1933, as amended.

          “ Similar Law ”: Any federal, state, local, non — U.S. or other law or regulation that contains one or more provisions that are similar to any of the provisions contained in Title I of ERISA or Section 4975 of the Code.

          “ Single Asset Debt Limit ”: As defined in Section 3.6(a)(ii)(B).

          “ SLR ”: Sumitomo Life Realty (N.Y.), Inc., a New York corporation.

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          “ SLR Designee ”: As defined in Section 5.3(a).

          “ SLRI ”: SLR Investments, Inc., a Delaware corporation.

          “ Subscription Agreement ”: As defined in Section 3.2(a).

          “ Sumitomo ”: SLR and SLRI, collectively.

          “ Super Majority Fund Vote ”: As defined in Section 11.7.

          “ Super Majority LP Vote ”: As defined in Section 11.6(g).

          “ Super Majority Partner Vote ”: As defined in Section 11.6(g).

          “ Tax Matters Partner ”: As defined in Section 11.4(a).

          “ Temporary Investment ”: Any repurchase agreements of primary Federal Reserve dealers using treasury securities only; bankers acceptances which are legal for purchase by the Federal Reserve Bank; United States Treasury bills and agency discount notes; commercial paper that is rated by Moody’s or S&P in its highest rating category; accounts or mutual funds which invest in any of the foregoing; and any other investment approved by the Advisory Committee as a Temporary Investment.

          “ Term ”: As defined in Section 2.9.

          “ Third Restated Agreement ”: As defined in the Recitals of this Agreement.

          “ Total Capital Base ”: That amount, for a particular Fiscal Quarter, which equals the sum of the Current Quarter Capital Base and the Prior Quarter Capital Base Surplus. For these purposes:

          (a) The “ Current Quarter Capital Base ” means that amount, for a particular Fiscal Quarter, which equals (i) in the case of any Fiscal Quarter that ends prior to termination of the Initial Investment Period, 2%, or in the case of any Fiscal Quarter that ends after termination of the Initial Investment Period, 1%, multiplied by (ii) the total amount of Capital Contributions made during such Fiscal Quarter by Unaffiliated Limited Partners.

          (b) The “ Prior Quarter Capital Base Surplus ” means that amount, for a particular Fiscal Quarter, which equals the excess (if any) of (i) the Total Capital Base for the immediately preceding Fiscal Quarter, over (ii) the Total Property Base for the immediately preceding Fiscal Quarter; provided, however , that solely for purposes of applying the provisions of clause (a)(iii) of the Percentage Interest definition and Section 5.9(d) (but not for purposes of applying the provisions of Section 7.3), the Prior Quarter Capital Base Surplus for the first Fiscal Quarter ending after termination of the Investment Period shall be assumed to be zero and the Prior Quarter Capital Base Surplus for each Fiscal Quarter thereafter shall be determined based on such assumption.

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          “ Total Capital Base Share ”: That amount, for a particular Unaffiliated Limited Partner for a particular Fiscal Quarter, which equals the Total Capital Base for such Fiscal Quarter, multiplied by a fraction whose numerator equals the amount of such Limited Partner’s Capital Contributions during such Fiscal Quarter, and whose denominator equals the amount of Capital Contributions of all Unaffiliated Limited Partners during such Fiscal Quarter; provided, however , that in a cases where such Total Capital Base includes a Prior Quarter Capital Base Surplus, the numerator of such fraction shall be increased by the amount of such Limited Partner’s Capital Contributions during each prior Fiscal Quarter to which such Prior Quarter Capital Base Surplus is attributable, and the denominator of such fraction shall be increased by the amount of Capital Contributions of all Unaffiliated Limited Partners during each prior Fiscal Quarter to which such Prior Quarter Capital Base Surplus is attributable.

          “ Total Property Base ”: That amount, for a particular Fiscal Quarter, which equals the sum of the Current Quarter Property Base and the Prior Quarter Property Base Surplus. For these purposes,

          (a) The “ Current Quarter Property Base ” means that amount, for a particular Fiscal Quarter, which equals the product of (A) in the case of any Fiscal Quarter that ends prior to termination of the Initial Investment Period, 1%, or in the case of any Fiscal Quarter that ends after termination of the Initial Investment Period, 0.5%, multiplied by (B) the value of the total consideration (including any assumed Indebtedness) paid in respect of each Property in which US Core Properties (or, if applicable, any other Fund Entity through which the Partnership owns an interest the Property) acquired an interest, directly or indirectly, during such Fiscal Quarter, other than any Property acquired from SLR or any of its Affiliates, multiplied by (C) the percentage ownership interest in such Property acquired, directly or indirectly, by US Core Properties (or, if applicable, by such other Fund Entity through which the Partnership owns an interest in the Property) as a result of such acquisition, multiplied by (D) the product of (x) the aggregate ownership percentage of the Unaffiliated Limited Partners in the Partnership as of the end of such Fiscal Quarter, multiplied by (y) the aggregate ownership percentage of the Partnership in US Core Trust (or, if applicable, in any other Fund Entity through which the Partnership owns an interest in the Property) as of the end of such Fiscal Quarter, multiplied by (z) if applicable, US Core Trust’s ownership percentage in US Core Properties (or, if applicable, in any other Fund Entity through which US Core Trust owns an interest in the Property) as of the end of such Fiscal Quarter.

          (b) The “ Prior Quarter Property Base Surplus ” means that amount, for a particular Fiscal Quarter, which equals the excess (if any) of (i) the Total Property Base for the immediately preceding Fiscal Quarter, over (ii) the Total Capital Base for the immediately preceding Fiscal Quarter; provided, however , that solely for purposes of applying the provisions of clause (a)(iii) of the Percentage Interest definition and Section 5.9(d) (but not for purposes of applying the provisions of Section 7.3), the Prior Quarter Property Base Surplus for the first Fiscal Quarter ending after termination of the Investment Period shall be deemed to be zero and the Prior Quarter Property Base Surplus for each Fiscal Quarter thereafter shall be determined based on such assumption.

          “ Transfer ”: As a noun, any sale, transfer, gift, exchange, assignment, devise or other disposition, as well as any other event that causes any Person to acquire beneficial

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ownership, or any agreement to take any such actions or cause any such events, with respect to Partnership Interests, or the right to vote or receive distributions with respect to Partnership Interests, including (a) the granting or exercise of any option (or any disposition of any option), (b) any disposition of any securities or rights convertible into or exchangeable for Partnership Interests or any interest in Partnership Interests or any exercise of any such conversion or exchange right and (c) Transfers of interests in other entities that result in changes in beneficial ownership of Partnership Interests; in each case, whether voluntary or involuntary, whether owned of record or beneficially owned, and whether by operation of law or otherwise. The terms “Transferor,” “Transferee,” “Transferred” and “Transferring” have correlative meanings.

          “ Trust ”: NY Trust, NY Trust II, and US Core Trust, and any successor to any of the foregoing.

          “ Unaffiliated Limited Partner ” A Limited Partner that is not an Affiliate of the Managing General Partner.

          “ Unfunded Commitment ”: As defined in Section 3.2(a).

          “ Unrecovered Capital ”: An amount, determined for each Partner or other Fund Investor, which equals the aggregate amount of all Capital Contributions made by such Limited Partner or Fund Investor to the Partnership or another Operating Company less the aggregate amount of capital returned to such Limited Partner or Fund Investor by the Partnership or other Operating Company by either the redemption of Partnership Units or the distribution of Capital Cash Flow.

          “ US Core Properties ”: Hines-Sumisei US Core Office Properties LP, a Delaware limited partnership, and its successors.

          “ US Core Properties Partnership Agreement ”: The Second Amended and Restated Agreement of Limited Partnership, dated as of September 20, 2004, of US Core Properties.

          “ US Core Trust ”: Hines-Sumisei US Core Office Trust, a Maryland real estate investment trust, and its successors.

          “ US Core Trust Declaration of Trust ”: The Amended and Restated Declaration of Trust of US Core Trust.

          “ Voting Fund Investors ”: All Fund Investors, including Partners holding Voting Interests, other than Fund Investors whose only equity interest in a Fund Entity or Property is specifically designated a non-voting interest under the Constituent Documents of the issuer of such equity interest.

          “ Voting Interests ”: Voting Units and Participation Interests.

          “ Voting Units ”: All Partnership Units other than Class N Partnership Units.

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          “ 600 Lexington ”: The office property having such name located at 600 Lexington Avenue/101 East 52nd Street in New York City.

          “ 75% Majority Fund Vote ”: As defined in Section 11.7.

          “ 75% Majority LP Vote ”: As defined in Section 11.6(g).

          “ 75% Majority Partner Vote ”: As defined in Section 11.6(g).

     SECTION 1.2 Interpretation; Terms Generally . The definitions set forth in Section 1.1 and elsewhere in this Agreement shall apply equally to both the singular and plural forms of the terms defined. Whenever the context may require, any pronoun shall include the corresponding masculine, feminine and neuter forms. Unless otherwise indicated, the words “include”, “includes” and “including” shall be deemed to be followed by the phrase “without limitation.” The words “herein”, “hereof” and “hereunder” and words of similar import shall be deemed to refer to this Agreement (including the Exhibits and Schedules) in its entirety and not to any part hereof, unless the context shall otherwise require. All references herein to Articles, Sections, Exhibits and Schedules shall be deemed to refer to Articles and Sections of, and Exhibits and Schedules to, this Agreement, unless the context shall otherwise require. Unless the context shall otherwise require, any references to any agreement or other instrument or statute or regulation are to it as amended and supplemented from time to time (and, in the case of a statute or regulation, to any corresponding provisions of successor statutes or regulations). Any reference in this Agreement to a “day” or number of “days” (that does not refer explicitly to a “Business Day” or “Business Days”) shall be interpreted as a reference to a calendar day or number of calendar days. If any action or notice is to be taken or given on or by a particular calendar day, and such calendar day is not a Business Day, then such action or notice shall be deferred until, or may be taken or given on, the next Business Day.

ARTICLE II

General Provisions

     SECTION 2.1 Formation and Continuation . The Partnership was formed as a limited partnership under the Act by the filing of its certificate of limited partnership (the “ Certificate ”) with the Secretary of State of the State of Delaware on August 8, 2003. The Managing General Partner shall continue as a general partner of the Partnership, shall be a “general partner” for all purposes under the Act, and shall have those rights and obligations provided for the Managing General Partner under this Agreement. Each Person admitted as a Limited Partner prior to the date hereof shall continue as a limited partner of the Partnership. The Non-Managing General Partner is hereby admitted as a general partner of the Partnership, shall be a “general partner” for all purposes under the Act, and shall have those rights and obligations provided for the Non-Managing General Partner under this Agreement. As of the date hereof, each Person identified as a Limited Partner on Schedule 2.1 is a Limited Partner. The Managing General Partner may amend Schedule 2.1 from time to time to reflect the admission of additional Limited Partners.

     SECTION 2.2 Name . The name of the Partnership shall be “Hines-Sumisei U.S. Core Office Fund, L.P.” The Managing General Partner shall, with the affirmative written consent of

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SLR (which consent shall not be unreasonably withheld) and upon notice to the other Partners, have the right to change the name of the Partnership and, in connection therewith, may execute and file (pursuant to the power-of-attorney provided for in Section 13.2, where necessary) such amendments to this Agreement, the Certificate and such other documentation, as shall be necessary or desirable to effect such name change. The Partnership shall do business under the name of the Partnership or under such other name (including any assumed name) as the Managing General Partner may from time to time determine in its sole discretion. Upon the dissolution and termination of the Partnership, the Managing General Partner shall retain all rights with respect to the name of the Partnership and the use of such name.

     SECTION 2.3 Organizational Certificates and Other Filings . If requested by the Managing General Partner, the Limited Partners will promptly execute all certificates and other documents consistent with the terms of this Agreement necessary for the Managing General Partner to accomplish all filing, recording, publishing and other acts as may be appropriate to comply with all requirements for (a) the formation and operation of a limited partnership under the laws of the State of Delaware, (b) if the Managing General Partner deems it advisable, the operation of the Partnership as a limited partnership, or partnership in which the Limited Partners have limited liability, in all jurisdictions where the Partnership proposes to operate and (c) all other filings required to be made by the Partnership.

     SECTION 2.4 Principal and Other Offices . The principal executive office of the Partnership shall be c/o Hines Interests Limited Partnership, 2800 Post Oak Boulevard, Suite 5000, Houston, Texas 77056-6118, or such other place as may from time to time be designated by the Managing General Partner in its sole discretion. The Managing General Partner shall give prompt notice to each Partner of any change in the principal office of the Partnership. The Partnership may also have such other offices and places of business as the Managing General Partner determines to be appropriate.

     SECTION 2.5 Registered Office; Registered Agent . The address of the registered office of the Partnership in the State of Delaware shall be c/o Corporation Trust Company, 1209 Orange Street, Wilmington, Delaware 19801 or such other place as may be designated from time to time by the Managing General Partner in its sole discretion. The name and address of the registered agent for the Partnership in the State of Delaware which shall act as its agent for service of process in the State of Delaware shall be The Corporation Trust Company, 1209 Orange Street, Wilmington, Delaware 19801, or such other agent as may be designated from time to time by the Managing General Partner in its sole discretion.

     SECTION 2.6 Purpose . The purpose of the Partnership is to hold an interest in NY Trust, NY Trust II, US Core Trust and any other Operating Company that may hereafter be organized for the purpose of making investments in accordance with the Investment Guidelines, to make capital contributions to, and otherwise provide for the financing of, such Operating Companies, to influence or exercise control over the management and policies of such Operating Companies through the ownership of voting securities, the power to appoint members to the board of trustees or other governing body of such Operating Companies, by contract or otherwise, and to engage in such other activities as are permitted under this Agreement or are incidental or ancillary thereto as the Managing General Partner deems necessary or advisable, all upon the terms and conditions set forth in this Agreement.

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     SECTION 2.7 Powers .

     (a) The Partnership shall have all the powers now or hereafter conferred by the laws of the State of Delaware on limited partnerships formed under the Act and, subject to the express limitations set forth in this Agreement, may do any and all lawful acts or things that are necessary, appropriate, incidental or convenient for the furtherance and accomplishment of the purposes of the Partnership or for the protection and benefit of the Partnership or its properties and assets. Without limiting the generality of the foregoing, and subject to the terms of this Agreement, the Partnership may enter into, deliver and perform all contracts, agreements and other undertakings and engage in all activities and transactions as may be necessary or appropriate to carry out its purposes and conduct its business.

     (b) Without limiting the foregoing, and notwithstanding anything in this Agreement to the contrary, the Partnership, and the Managing General Partner on behalf of the Partnership, is authorized and empowered to enter into, deliver and perform its obligations and exercise its rights under each of Approved Agreements.

     SECTION 2.8 Fiscal Year . The fiscal year (“ Fiscal Year ”) and taxable year of the Partnership will be the calendar year, and its fiscal quarters (each, a “ Fiscal Quarter ”) shall end on the last day of each calendar quarter. The Managing General Partner may change the ending date of the Fiscal Year if the Managing General Partner determines in good faith that such change is necessary or appropriate. The Managing General Partner will change the taxable year of the Partnership if and to the extent necessary to comply with Code Section 706 and the Regulations thereunder. The Managing General Partner will give prompt written notice of any such change to the other Partners.

     SECTION 2.9 Term . The term of the Partnership (the “ Term ”) commenced upon the filing of the Certificate and shall continue until the Partnership is dissolved and its affairs are wound up in accordance with Article XII.

     SECTION 2.10 Feeder Entities . In order to facilitate investment in the Partnership by certain investors, the Managing General Partner may establish or facilitate the establishment of one or more collective investment vehicles or other arrangements (each such vehicle or arrangement, a “ Feeder Entity ”) through which investors may invest in the Partnership by acquiring interests in such Feeder Entity. Affiliates of the Managing General Partner may hold interests in any such Feeder Entity or in the general partner (or advisor or similar entity) of such Feeder Entity. In case of a default by any such Feeder Entity, the Managing General Partner may treat one or more of such investors (rather than such Feeder Entity) as a Defaulting Partner as provided in Section 10.8. In addition, the terms of the governance and/or organizational documents of any such Feeder Entity may permit the payment to the general partner (or advisor or similar entity) of such Feeder Entity of management, advisory or other fees, and any such fees paid by such Feeder Entity to its general partner (or advisor or other entity) may be used to reduce and offset the Asset Management Fee or Acquisition Fees payable under this Agreement, in which event the Managing General Partner shall amend this Agreement so that the benefit of any such reduction inures to such Feeder Entity.

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     SECTION 2.11 REIT Covenant . It is the goal of the Partners that each Operating Company that is a REIT shall at all times be a “domestically controlled REIT” as defined in Section 897(h)(4) of the Code. The Partnership shall not take any action or engage in any activities (including exercising operating control over Operating Companies) on and after the date that the elections of NY Trust, NY Trust II or any other Operating Company under Section 856 of the Code to be taxed as a real estate investment trust first becomes effective (the “ REIT Election Effective Date ”) if both (i) such actions or activities would cause the Partnership to be treated as engaged in a U.S. trade or business for U.S. federal income tax purposes, or as owning U.S. real property interests within the meaning of Section 897 of the Code, at any time on and after the REIT Election Effective Date, and (ii) the Partnership is so treated as engaged in a U.S. trade or business or as owning U.S. real property interests other than because of the application and/or operation of Section 897(h) of the Code or because of the ownership of any interest in a real estate investment trust that is treated as a U.S. real property corporation under Section 897(c)(2) of the Code.

ARTICLE III

Partnership Capital

     SECTION 3.1 Partnership Capital . As of the date of this Agreement, the Partners have been issued Units and have Funded Commitments in the amounts set forth opposite their names on Schedule 3.1 . The Managing General Partner shall record all issuances and redemptions of Units on the books of the Partnership. Except as specifically provided in this Agreement or any Subscription Agreement, no Partner (including the Managing General Partner and the Non-Managing General Partner) shall be required to, and no Limited Partner shall have the right to, contribute additional funds or other property to the Partnership. The Partnership may from time to time incur Indebtedness in accordance with Section 3.6 and issue additional Units in accordance with Sections 3.2 and 3.7.

     SECTION 3.2 Capital Commitments .

     (a) The Partnership may from time to time, in the discretion of the Managing General Partner, issue additional Partnership Units and admit additional Limited Partners to the Partnership. Any Person that acquires Partnership Units for cash (an “ Investor ”) will acquire such Units pursuant to an agreement (a “ Subscription Agreement ”) between such Investor and the Partnership pursuant to which such Investor agrees to acquire, and the Partnership agrees to issue, Partnership Units in exchange for Capital Contributions in cash on such terms and conditions as are provided in this Agreement and as may be provided in such Subscription Agreement. A Subscription Agreement shall become effective as of the date it has been executed and delivered by the Investor party thereto and accepted by the Managing General Partner on behalf of the Partnership. Units issuable pursuant to a Subscription Agreement may be issuable in installments, with each installment being issuable, and the Capital Contribution therefor being payable, in accordance with calls for capital (“ Capital Calls ”) issued pursuant to written notice (the “ Capital Call Notice ”) to the Investor party to such Subscription Agreement. The total purchase price payable by any Investor under a Subscription Agreement for the Units issuable pursuant thereto is referred to as such Investor’s “ Capital Commitment ”. Each

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Investor which acquires any Units pursuant to a Subscription Agreement shall be deemed to be admitted to the Partnership as a Partner immediately upon the payment of the purchase price for the first Units so issued to such Investor. The aggregate amount of Capital Contributions made by a Partner (in cash or property) is referred to herein as such Partner’s “ Funded Commitment ”, and the portion of the Capital Commitment provided for in any Subscription Agreement that remains unpaid after any closing of a purchase and issuance of Units thereto shall be referred to as the “ Unfunded Commitment ” of the Partner party to such Subscription Agreement. Except as provided in Section 11.4(c), in no event will any Partner be required to contribute any capital to the Partnership in excess of such Partner’s Capital Commitment.

     (b) If at any time the Managing General Partner determines to raise capital by issuing Capital Calls to Partners having Unfunded Commitments, it shall generally issue such Capital Calls pro rata to each such Partner in proportion to the Unfunded Commitment of each such Partner. However, the Managing General Partner may, in its discretion, issue Capital Calls other than pro rata to the extent required by the terms of any Subscription Agreement or other agreement between the Partnership or the Managing General Partner and one or more Partners, or if the Managing General Partner otherwise deems it advisable to issue Capital Calls in some manner other than pro rata (for example, to assist in achieving or maintaining the status of any REIT in which the Partnership has a direct or indirect interest as a “domestically controlled” REIT). Each Capital Call Notice issued by the Managing General Partner shall specify the account to which Capital Contributions are to be delivered pursuant thereto and the date on which such Capital Contributions are due (“ Payment Date ”), which date shall be no sooner than ten Business Days after the date such Capital Call Notice is issued. All Capital Contributions made on or before the Payment Date specified in a Capital Call Notice shall be deemed to have been made on such Payment Date.

     SECTION 3.3 Initial Offering Period . The period beginning on February 2, 2004, and ending on November 2, 2004, is referred to herein as the “ Initial Offering Period ”. The parties acknowledge that all Subscription Agreements entered into prior to the end of the Initial Offering Period provide for the issuance of Units at the Initial Offering Price.

     SECTION 3.4 Initial Investment Period . The three-year period beginning on February 2, 2004, and ending on February 2, 2007, is referred to herein as the “ Initial Investment Period ”; provided that the Managing General Partner may extend the Initial Investment Period to end on the latest closing date of any Investment with respect to which the Partnership, or the Managing General Partner on behalf of the Partnership, entered into a binding agreement on or prior to the last day of such initial three year period; provided further that the Initial Investment Period shall in no event be extended beyond February 2, 2008. Upon the termination of the Initial Investment Period, as it may be extended pursuant to the preceding sentence, any remaining Unfunded Commitments attributable to Subscription Agreements entered into during the Initial Offering Period shall be canceled automatically and without any further action by any party, and the Managing General Partner shall have no further right to issue Capital Calls, and Investors shall have no further right to purchase Units in respect of such canceled Unfunded Commitments pursuant to any such Subscription Agreement; provided that the foregoing shall not affect (i) the right of the Managing General Partner or the Partnership to pursue any remedies available to it

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under this Agreement or at law in respect of any default in respect of a Capital Call issued prior to the termination of the Initial Investment Period, or (ii) the obligation of any Partner with respect to a Capital Commitment attributable to a Subscription Agreement entered into after the Initial Offering Period.

     SECTION 3.5 Designation of Class N Units .

     (a) There is hereby designated a class of Partnership Units referred to as “ Class N Partnership Units ”. Class N Partnership Units shall be identical in all respects to Partnership Units generally, except that holders of Class N Partnership Units shall have no right to participate in any LP Vote, Partner Vote or Fund Vote and shall have no right to vote, consent or make any decision on any matter with respect to which Partners are otherwise permitted to vote, consent or make any decision on under the terms of this Agreement other than as contemplated by clause (i) of the proviso of the first sentence of Section 13.3(a). Each Partner holding Class N Partnership Units hereby further irrevocably waives its corresponding right to vote for a successor general partner under the Act with respect to such Class N Partnership Units, which waiver shall be binding upon such Partner and any Person that succeeds to its interest.

     (b) The Managing General Partner may cause the Partnership to issue Class N Partnership Units in the same manner and on the same terms as this Agreement provides for the issuance of Partnership Units generally. Each Class N Partnership Unit interest shall remain a non-voting interest at all times and shall continue as a non-voting interest with respect to any assignee or other transferee of such interest.

     (c) Except where the context otherwise requires, all references in this Agreement to “Partnership Units” or “Units” shall be deemed to be references to undesignated Partnership Units and Class N Partnership Units, collectively.

     SECTION 3.6 Fund Indebtedness .

     (a) The Managing General Partner shall have the right, at its option, to cause any Fund Entity other than the Partnership to incur or assume Indebtedness from any Person to finance Investments made, directly or indirectly, and to pledge or otherwise encumber assets of any such Fund Entity to secure any such Indebtedness, subject to the following:

     (i) The Partnership shall not consent to NY Trust and its subsidiaries incurring any Indebtedness in excess of 55% of the Current Market Value of the Investments held by NY Trust at the time any such Indebtedness is incurred, and, the Partnership will not consent to NY Trust II and its subsidiaries incurring any Indebtedness in excess of 55% of the Current Market Value of 600 Lexington at the time any such Indebtedness is incurred.

     (ii) The Fund shall not incur any Indebtedness other than the Indebtedness permitted under clause (i) of this Section 3.6(a) unless, after giving effect to such incurrence,

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     (A) the aggregate amount of such other Indebtedness is not more than 50% of the Current Market Value of all Investments other than the Initial Asset Group at the time any such other Indebtedness is incurred (the “ Aggregate Debt Limit ”); and

     (B) the total amount of Indebtedness that is secured by any one Investment other than one of the Initial Asset Group shall not exceed 65% of the Current Market Value of such Investment at the time such Indebtedness is incurred (the “ Single Asset Debt Limit ”).

     (iii) Notwithstanding clause (ii) of this Section 3.6(a), the Managing General Partner may cause the Partnership to consent to the Fund incurring Indebtedness in excess of the Aggregate Debt Limit and/or the Single Asset Debt Limit, if the Managing General Partner determines that it is advisable to do so, provided that, at the time any such excess Indebtedness is incurred, the Managing General Partner makes a reasonable determination that such excess Indebtedness will be repaid within one year after the incurrence of such excess Indebtedness.

     (b) In connection with the incurrence of Indebtedness by any Fund Entity, the Managing General Partner shall have the right, in its discretion, to pledge to the lender the right of the Managing General Partner to issue Capital Calls in respect of the Unfunded Commitments of the Partners, and to enforce the obligations of the Partners to make Capital Contributions in respect thereof, in accordance with the terms and conditions of this Agreement and the Subscription Agreements. Each Partner having an Unfunded Commitment shall, upon the written request of the Managing General Partner, for the benefit of one or more lenders or other Persons extending credit to the Partnership, (A) acknowledge its obligations pursuant to this Agreement and its Subscription Agreement to make Capital Contributions (which may, as determined by the Managing General Partner, include an acknowledgment that the Managing General Partner, or the lender on behalf of the Managing General Partner (in accordance with the agreements between such lender and the Partnership and/or the Managing General Partner), may call such Capital Contributions in accordance with this Agreement and such Partner’s Subscription Agreement to pay the outstanding obligations to such lenders without, except as expressly set forth in this Agreement, defense, counterclaim or offset of any kind); provided that the liability of the Partners to make Capital Contributions shall not be increased thereby and shall not result in the loss of a Partner’s limited liability status under this Agreement, and (B) execute such documents as may be reasonably required to create a security interest in such Partner’s obligations to make such Capital Contributions, which the Managing General Partner may perfect and assign for the benefit of a lender as determined by the Managing General Partner in its sole discretion. For purposes of determining whether the Fund’s Indebtedness is within the Aggregate Debt Limit, Indebtedness secured by a pledge of the Managing General Partner’s right to make Capital Calls in respect of the Partners’ Unfunded Commitments (or in respect of the unfunded commitments of any investor in any Fund Entity) shall not be treated as outstanding Indebtedness; provided that no assets of the Partnership are pledged to secure such Indebtedness other than the right of the Managing General Partner to issue Capital

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Calls in respect of the Unfunded Commitments of the Partners and to enforce the obligations of the Partners to make Capital Contributions in respect thereof.

     SECTION 3.7 Issuance of Units and Participation Interest .

     (a) The Partnership may issue Units, as determined by the Managing General Partner, in its discretion, to existing or newly-admitted Partners, (i) in exchange for the making by such a Partner (a “ Contributing Partner ”) of a Capital Contribution to the Partnership in cash, or (ii) in connection with the acquisition, directly or indirectly, of an Investment from such Contributing Partner or an Affiliate of such Contributing Partner by one or more Operating Companies, subject to the following:

     (i) The Partnership may issue Partnership Units at a price per Unit of not less than the Current Unit Value as of the date of issuance.

     (ii) The Partnership may issue Partnership Units in installments pursuant to a Subscription Agreement by which an Investor has made a binding Capital Commitment, with the price per Unit for each issuance of Units pursuant to such Subscription Agreement determined by reference to (A) the Current Market Value of the Properties in which the Partnership has an indirect interest as of the date of such Subscription Agreement (or, if different, as of the date that, and to such extent as, the Investor’s Capital Commitment becomes binding pursuant to the terms of such Subscription Agreement), (B) the acquisition cost of each Property in which the Partnership acquires an interest after such date and on or before the date of such issuance, and (C) the assets and liabilities of the Partnership and its subsidiaries other than interests in Properties as of the date of such issuance.

     (iii) The Partnership may issue Partnership Units to Limited Partners that entered into Subscription Agreements during the Initial Offering Period at a price per Unit equal to $1000 per Unit to the extent provided in any such Subscription Agreement.

     (iv) The Partnership may issue Partnership Units at a price per Unit other than as provided in clause (i), (ii), or (iii) above only with the consent of the Partners by a Super Majority Partner Vote.

     (b) The Managing General Partner will cause the Partnership not to consent to or, to the extent the Partnership Controls the issuance of securities by any such Fund Entity, permit NY Trust, NY Trust II or any other Fund Entity (other than US Core Trust) in which the Partnership has a direct equity interest (or any subsidiary of any such Fund Entity) to issue equity interests to third party investors other than as contemplated by clause (i) or (ii) of Section 3.7(a) without the consent of the Partners by a Super Majority Partner Vote. The Managing General Partner will cause the Partnership not to consent to or, to the extent the Partnership Controls the issuance of securities by any such Fund Entity, permit US Core Trust or any subsidiary of US Core Trust (other than US Core Properties and subsidiaries of US Core Properties) to issue equity interests to third party

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investors other than as contemplated by clause (i) or (ii) of Section 3.7(a) without the written consent of Voting Fund Investors holding, without duplication, sixty-six and two-thirds percent (66 2/3%) or more of the aggregate outstanding equity interests in the Partnership and US Core Trust held by Voting Fund Investors, excluding any equity interest which is specifically designated a non-voting interest under the Constituent Documents of the issuer of such equity interest. The Managing General Partner will take such action as is necessary to prevent US Core Properties or any Fund Entity that US Core Properties Controls from issuing equity interests to third party investors other than as contemplated by clause (i) or (ii) of Section 3.7(a) without the written consent of Voting Fund Investors holding, without duplication, sixty-six and two-thirds percent (66 2/3%) or more of the aggregate outstanding equity interests in the Partnership, US Core Trust and US Core Properties held by Voting Fund Investors, excluding any equity interest which is specifically designated a non-voting interest under the Constituent Documents of the issuer of such equity interest. This Section 3.7(a) is subject to Section 5.3(b)(iv).

     (c) (i) Effective as of the date of the Second Restated Agreement, the Partnership issued to each of Hines and SLR a limited partnership interest denominated as a “ Participation Interest .” The Participation Interest is an equity interest in the Partnership which is granted in consideration for services rendered by Hines and SLR as Investment Advisors to the Managing General Partner and the Partnership pursuant to the Advisory Agreement. The Participation Interest is in addition to, and distinct from, the Units described above, and any references to “Units” or “Partnership Units” shall not be deemed to include the Participation Interest. A Partner’s percentage interest attributable to its Participation Interest (if any), together with the percentage of the total outstanding Units held by it, equal its Percentage Interest in the Partnership. The Participation Interest is an interest solely in profits and shall not have any Capital Commitment or initial Capital Account associated with it. It is intended that the Participation Interest constitute a profits interest within the meaning of Section 2.02 of IRS Revenue Procedure 93-27, 1993-2 C.B. 343.

     (ii) The formula for calculation of the Participation Interest is included in the definition of Percentage Interest in Section 1.1, and Schedule 5.9 provides an example of how the Percentage Interest for the holder of a Participation Interest is calculated. The Participation Interest is intended to provide each Investment Advisor holding it with an interest in the Partnership that approximates the interest it would acquire if it received Asset Management Fees and Acquisition Fees after the Initial Investment Period in the same amounts payable in respect of such fees during the Initial Investment Period and then invested half of such amounts in the Partnership through the acquisition of additional Partnership Units. (However, since the Participation Interest is a profits interest, this interest will be substantially economically equivalent to the ownership of Partnership Units only if the Partnership has adequate gain or profit to allocate to the holder of the Participation Interest.) Without considering the effect of additional equity investments or redemptions by existing or new Partners, the grant of the Participation Interest has the effect of decreasing the Percentage Interest of all Unaffiliated Limited Partners after the Initial Investment

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Period as the Percentage Interest associated with the Participation Interests increases in a manner corresponding to the accrual of additional Asset Management Fees and Acquisition Fees that would occur if such fees were payable in cash after the Initial Investment Period in the same amounts as such fees are payable during the Initial Investment Period pursuant to the terms of this Agreement. This is accomplished by the Unit cancellation procedure described in Section 5.9. ( Schedule 5.9 provides an example of Unit cancellations as contemplated by Section 5.9.)

     (iii) SLR may, at any time prior to the end of the Initial Investment Period, elect to return its Participation Interest to the Partnership by giving written notice to such effect to the Managing General Partner. In such event, the Managing General Partner shall amend this Agreement and the Advisory Agreement (in a manner reasonably acceptable to SLR) as necessary to provide for (A) only Hines having a Percentage Interest calculated by reference to a Participation Interest, and (B) the payment to the Managing General Partner for the benefit of SLR of additional cash amounts in respect of Asset Management Fees and Acquisition Fees to which SLR would be entitled under the Advisory Agreement if the Partnership continued to pay such fees after the Initial Investment Period in the manner that such fees are required to be paid under this Agreement during the Initial Investment Period.

     SECTION 3.8 Redemption Rights . Subject to and in accordance with the provisions of this Section 3.8, each Partner shall have the right (a “ Redemption Right ”) to request that the Partnership redeem for cash at the Current Unit Value in the case of Units, or at the Current Participation Interest Value in the case of a Participation Interest, all or a portion of the Units or Participation Interest held by such Partner by delivering a notice (a “ Notice of Redemption ”) to the Partnership and the Managing General Partner specifying the number of Units or the portion of the Participation Interest held by such Partner (a “ Redeeming Partner ”) that it requests to be redeemed at any time within the last 45 days of any calendar year ending after the later of (i) the last day of the Initial Investment Period and (ii) the first anniversary of the date such Partner acquired the Units or such portion of its Participation Interest that it seeks to redeem. If, and beginning with the first day of the first taxable year in which, the Partnership no longer qualifies for the Private Placement PTP Exemption, the Redemption Right shall comply with the requirements of Regulations Section 1.7704-1(f) and shall be construed and administered in accordance therewith. The Managing General Partner may modify the Redemption Right from time to time in its discretion to ensure that the terms of the Redemption Right comply and continue to comply with such requirements. If a Partner requests a redemption pursuant to the first sentence of this Section 3.8 (a “ Liquidating Redemption ”), the Managing General Partner shall use its reasonable best efforts to cause the Partnership to redeem the number of Units or the portion of the Participation Interest specified in the Notice of Redemption for cash at the Current Unit Value in the case of Units, or at the Current Participation Interest Value in the case of a Participation Interest, in each case as of the date of redemption, on or before the last day of the calendar year following the year in which such Notice of Redemption was delivered, subject to the following:

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     (a) In no event shall the Partnership be required to redeem for cash in any calendar year Partnership Units and Participation Interests which, when taken together with all interests in US Core Trust and US Core Properties which Fund Investors having interests therein are seeking to redeem pursuant to corresponding redemption rights under the Constituent Documents of such Entities, exceed, in the aggregate, 10% of the total equity capitalization of the Partnership, US Core Trust and US Core Properties (calculated without duplication of equity held directly or indirectly in any such Entity by any other such Entity) as of the first day of such calendar year. If, for any calendar year, Partners and such Fund Investors request such liquidating redemptions in excess of such 10% limit, then each Partner entitled to participate in such redemption shall be entitled to redeem its pro rata share of the total equity in the Partnership, US Core Trust and US Core Properties requested to be redeemed in such calendar year based on the amount of such equity requested to be redeemed in each such Fund Investor’s Notice of Redemption.

     (b) If more than one Fund Investor submits a request for a Liquidating Redemption in a calendar year, then funds available to effect such redemptions shall be applied pro rata to the redemption of the interests in the Partnership, US Core Trust and/or US Core Properties subject to each such Fund Investor’s Notice of Redemption, based on such Fund Investor’s share of the total amount of equity to be redeemed.

     (c) In no event will any Units or Participation Interests (or interests in US Core Trust or US Core Properties) be redeemed pursuant to a Liquidating Redemption to the extent that (i) the Managing General Partner determines in good faith that such redemption would be inconsistent with the best interests of the Partnership or any Operating Entity, (ii) such redemption would result in any REIT in which the Partnership has a direct or indirect interest ceasing to be a “domestically controlled REIT” as defined in Section 897(h)(4) of the Code or would violate or result in a violation of the Constituent Documents of any Operating Company in which the Partnership has a direct or indirect interest, or (iii) the Partnership is unable to raise or acquire sufficient funds to make such Liquidating Redemption on terms acceptable to the Partnership, as determined by the Managing General Partner in good faith.

     (d) If, and beginning with the first day of the first taxable year in which, the Partnership no longer qualifies for the Private Placement PTP Exemption:

     (i) A Partner shall be entitled to exercise the Redemption Right only if (x) the redemption or purchase of the Partner’s Units and/or Participation Interest would constitute a Private Transfer or (y) the Percentage Interest attributable to the Units and Participation Interest to be redeemed, when aggregated with other Transfers of Partnership Interests within the same taxable year of the Partnership (but not including Private Transfers), would constitute a Percentage Interest of ten percent (10%) or less in the Partnership.

     (ii) The Managing General Partner may establish such policies and procedures as it may deem necessary or desirable in its discretion, including imposing limitations on the number of Units and portion of Participation Interest

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with respect to which the Redemption Right may be exercised during any period of time shorter than a calendar year (and causing similar limitations to be imposed with respect to redemptions of interests in US Core Trust and US Core Properties) and establishing procedures to allocate the ability to exercise the Redemption Right among the Partners (and causing similar procedures to be established with respect to US Core Trust and US Core Properties).

     (iii) The restrictions set forth in subparagraphs (i) and (ii) of this Section 3.8(d) shall continue in effect until such time as the Partnership is no longer potentially subject to classification as a publicly traded partnership, as defined in Code Section 7704, in the absence of such restrictions, as determined by the Managing General Partner in its discretion. The restrictions set forth in such clauses (i) and (ii), together with the restrictions on the Transfer of Partnership Interests set forth in Section 10.5(b)(ii), are intended to limit transfers of interests in the Partnership in such a manner as to permit the Partnership to qualify for the safe harbors from treatment as a publicly traded partnership set forth in Treasury Regulations Sections 1.7704-1(d), (e), (f) and (j) and shall be construed and administered in accordance therewith. The Managing General Partner may modify the restrictions set forth in such clauses (i) and (ii), and the provisions of Section 10.5(c), from time to time in its discretion to ensure that the Partnership complies and continues to comply with the requirements of the Code and Regulations described above.

     (e) Each Notice of Redemption requesting a Liquidating Redemption will expire and be of no further force or effect as of the last day of the calendar year following the year in which such Notice of Redemption was delivered. A Partner (or other Fund Investor) will be entitled to participate in Liquidating Redemptions in any given calendar year only to the extent of the Units and the portion of the Participation Interest (or other interest in the Fund) subject to a Notice of Redemption requesting a Liquidating Redemption within the last forty-five days of the preceding calendar year.

     (f) A Limited Partner shall not be entitled to exercise a Redemption Right if it prejudices or affects the continuity of the Partnership for purposes of Code Section 708. Prior to any such redemption, the Managing General Partner may require an opinion of counsel, which counsel and opinion shall be satisfactory to the Managing General Partner, to the effect that such redemption will not cause adverse tax consequences to the non-redeeming Partners, and such Limited Partner exercising the Redemption Right shall be responsible for paying said counsel’s fee for such opinion.

     SECTION 3.9 Priority Redemption Rights . In connection with the issuance of Units to a Contributing Partner, the Partnership may agree, subject to the terms of any outstanding Priority Redemption Rights, in the sole discretion of the Managing General Partner, as part of the terms and conditions for such issuance, to grant such Contributing Partner a right to redeem all or a portion of the Units issued to such Limited Partner in such issuance at a redemption price equal to the Current Unit Value at the time of redemption on or before a specified date or dates (any such preferential or modified redemption right, a “ Priority Redemption Right ”). Pursuant to any such agreement, the Managing General Partner may apply any Capital Cash Flow and any funds

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received from Capital Contributions of Partners that would otherwise be available for making distributions to the Partners or redeeming Units pursuant to Redemption Rights generally to the making of any redemptions required to be made pursuant to any Priority Redemption Rights. Redemptions made or required to be made pursuant to the exercise of Priority Redemption Rights are referred to herein as “ Priority Redemptions ”.

     SECTION 3.10 Hines Bridge Equity and Priority Redemption Right . Prior to the date hereof, the Managing General Partner and the Hines Limited Partner have collectively made Capital Contributions to the Partnership in excess of the Hines Capital Requirement at a price per Unit equal to the Initial Offering Price. Affiliates of Hines may from time to time in the future contribute equity to the Partnership and/or one or more Operating Companies or other Fund Entities which, taken together with other contributions by Affiliates of Hines, exceed the Hines Capital Requirement if the Managing General Partner determines that such contributions are necessary or advisable for the Fund to finance an Investment, meet the domestic control requirements set forth in the Constituent Documents of any Operating Company that is a REIT or for other purposes deemed appropriate by the Managing General Partner. Any such future contributions shall be at a price per Unit (or equivalent interest in another Fund Entity) equal to the Current Unit Value (or its equivalent), as of the date of the contribution. All past contributions and future contributions in excess of the Hines Capital Requirement by Affiliates of Hines to the Partnership or any Operating Company or other Fund Entity are referred to herein as “ Hines Bridge Equity ”. Notwithstanding any other provision of this Agreement, the Managing General Partner shall cause the Partnership (or applicable Operating Company) to apply the proceeds of all Capital Contributions made to the Partnership or any Operating Company from and after the date hereof to the redemption of any Hines Bridge Equity, to the extent that the Managing General Partner reasonably determines that such Hines Bridge Equity is no longer required. Such redemption shall be for cash in an amount per Unit (or equivalent interest) equal to the price per Unit (or equivalent interest) paid by the applicable Hines Affiliate for such interest, with appropriate adjustments for assets and liabilities of the Partnership other than its interests in Properties as of the date of redemption. The right to have any Hines Bridge Equity redeemed pursuant to this Section 3.10 shall be a Priority Redemption Right of the Hines Affiliate that contributed such equity. To the extent the Managing General Partner, the Hines Limited Partner or another Affiliate of Hines elects to exercise such Priority Redemption Right, the Managing General Partner may require all Partners whose Unfunded Commitments are greater than zero to make Capital Contributions in accordance with Section 3.2 up to the full amount of such Unfunded Commitments to the extent necessary to fund such redemption. Notwithstanding the foregoing, each of the Hines Limited Partner, the Managing General Partner and any other Affiliate of Hines that contributes Hines Bridge Equity may, in its sole and absolute discretion, waive or defer, in whole or in part, the exercise of the Priority Redemption Right granted to it pursuant to this Section 3.10. Each Affiliate of Hines that contributes or has contributed Hines Bridge Equity to the Partnership or any other Fund Entity shall be a third party beneficiary of this Section 3.10.

     SECTION 3.11 Hines Investment . The Managing General Partner, the Hines Limited Partner and/or such other Affiliates of Hines as the Managing General Partner may determine from time to time, shall maintain Unrecovered Capital in the Fund in an aggregate amount of not less than the greater of (i) 1% of the Unrecovered Capital of all Fund Investors, or (ii) $25 million (the “ Hines Capital Requirement ”); provided that, for purposes of determining whether

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the Hines Capital Requirement is met, (1) any amounts invested by Hines or any Affiliate of Hines in Hines Real Estate Investment Trust, Inc. or Hines REIT Properties, L.P., including, without limitation, any participation or profits interests granted to Hines or any Affiliate of Hines in either such Entity, shall be deemed to constitute Unrecovered Capital of Hines or such Affiliate of Hines in the Fund, and (2) the Non-Managing General Partner shall be deemed not to be a Fund Investor. In connection with any contribution of capital to an Operating Company by Fund Investors, the issuance of additional Partnership Units by the Partnership, the issuance of additional equity securities by any Operating Company or otherwise, the Managing General Partner shall, or shall cause an Affiliate of the Managing General Partner to, acquire additional Partnership Units or equity securities of one or more Operating Companies or other Fund Entities at the Current Unit Value (or its equivalent) to the extent necessary to comply with the Hines Capital Requirement. In order to manage the equity interests in the Fund held by the Managing General Partner and its Affiliates for purposes of complying with the Hines Capital Requirement, (A) the Managing General Partner, the Hines Limited Partner or any other Affiliate of Hines may, at any time, at the discretion of the Managing General Partner, contribute interests such Person holds in any Operating Company in which the Partnership has an interest to the Partnership in exchange for Partnership Units at Current Unit Value; and (B) the Managing General Partner may, at any time, in its discretion, cause the Partnership to exchange, at Current Unit Value, interests in any Operating Company held by the Partnership for interests in another Operating Company in which the Partnership holds an interest, or for Partnership Units, held by the Managing General Partner, the Hines Limited Partner or any other Affiliate of Hines; provided that, in any such case, such exchange does not result in the recognition of material amounts of taxable income or gain by the Partnership or any Fund Entity. Neither the Managing General Partner nor any other Affiliate of Hines shall be in breach of this Agreement if at any time the Hines Capital Requirement is not met as a result of dilution following the issuance of Partnership Units or interests in any Fund Entity so long as the Managing General Partner takes, or causes any Affiliate to take, such action as is necessary to cause the Hines Capital Requirement to be met as promptly as practicable following any such issuance.

ARTICLE IV

Managing General Partner

     SECTION 4.1 Managing General Partner . Subject to Section 5.11 and the other express limitations set forth in this Agreement, all rights and powers to manage and control the business and affairs of the Partnership shall be vested exclusively in the Managing General Partner, which shall have full authority to exercise in its discretion, on behalf of and in the name of the Partnership, all rights and powers of the sole general partner of a limited partnership formed under the Act. The Managing General Partner shall have the power to delegate all or any part of its rights and powers to manage and control the business and affairs of the Partnership to the Management Team, as provided in Section 5.5, or to such other officers, employees, Affiliates, agents and representatives of the Managing General Partner or the Partnership as it may from time to time deem appropriate. Any authority delegated by the Managing General Partner to any other Person shall be subject to the limitations on the rights and powers of the Managing General Partner specifically set forth in this Agreement.

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     SECTION 4.2 Powers of the Managing General Partner .

     (a) Subject to Section 5.11 and the other express limitations set forth in this Agreement, the power to direct the management, operation and policies of the Partnership shall be vested exclusively in the Managing General Partner, which shall have the power by itself and shall be authorized and empowered on behalf and in the name of the Partnership to carry out any and all of the objects and purposes of the Partnership and to perform all acts and enter into and perform all contracts and other undertakings that it may in its sole discretion deem necessary or advisable or incidental thereto, all in accordance with and subject to the other terms of this Agreement.

     (b) Without limiting the foregoing general powers and duties, the Managing General Partner is hereby authorized and empowered on behalf and in the name of the Partnership, or on its own behalf and in its own name, or through agents as may be appropriate, subject to the limitations contained elsewhere in this Agreement, to:

     (i) make all decisions concerning the Partnership’s interest in any Operating Company, including with respect to the voting of securities of such Operating Company, the appointment, removal and replacement of trustees, managers or directors of such Operating Company and the exercise of any rights and compliance with any obligations of the Partnership under any agreements with such Operating Company or to which such Operating Company is subject or with any Person having an interest in such Operating Company.

     (ii) make all decisions concerning, and enter into Advisory Agreements with Investment Advisors under which such Investment Advisors provide advice and recommendations to the Managing General Partner or the Partnership with respect to, the financing or operation of the Partnership, and the structuring, organization, formation, capitalization or financing of any Operating Company;

     (iii) direct the formulation of investment policies and strategies for the Partnership and any Operating Company, and select and approve the investment of Partnership funds in any Operating Company, all in accordance with the Investment Guidelines and the other limitations of this Agreement;

     (iv) sell, exchange, or otherwise dispose of all or any portion of the Partnership’s interest in any Operating Company and, in connection therewith, accept, collect, hold, sell, exchange, or otherwise dispose of evidences of Indebtedness or other property received pursuant thereto;

     (v) cause or consent to a merger, combination, recombination or consolidation of any Operating Company or other Fund Entity with any unrelated Entity or between or among two or more Operating Companies or other Fund Entities; or cause or consent to a transfer or exchange of Properties, interests in Fund Entities or other assets of or between one or more Operating Companies or other Fund Entities;

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     (vi) consent to any amendment to or restatement of the Constituent Documents of any Operating Company;

     (vii) open, maintain and close bank accounts and draw checks or other orders for the payment of money and open, maintain and close brokerage, money market fund and similar accounts;

     (viii) hire for usual and customary payments and expenses consultants, investment bankers, brokers, appraisers, attorneys, accountants and such other agents for the Partnership as it may deem necessary or advisable, and authorize any such agent to act for and on behalf of the Partnership;

     (ix) enter into, execute, maintain and/or terminate contracts, undertakings, agreements and any and all other documents and instruments in the name of the Partnership, and do or perform all such things as may be necessary or advisable in furtherance of the Partnership’s powers, objects or purposes or to the conduct of the Partnership’s activities, including entering into agreements to acquire or dispose of interests in Operating Companies which may include such representations, warranties, covenants, indemnities and guaranties as the Managing General Partner deems necessary or advisable;

     (x) incur Indebtedness and provide indemnities in connection therewith, on a recourse (only with respect to the assets of the Partnership or any Fund Entity) or non-recourse basis, on behalf of any Fund Entity other than the Partnership and, in its discretion, secure any and all of such Indebtedness with the assets of any Fund Entity, including the Unfunded Commitments of the Partners, and to assign the Partnership’s and the Managing General Partner’s rights to issue Capital Calls and to deliver Capital Call Notices to the Partners, to receive Capital Contributions from Partners and to enforce such rights under the terms of this Agreement and any Subscription Agreement;

     (xi) act as the “tax matters partner” under the Code and in any similar capacity under state, local or foreign law;

     (xii) make, in its sole discretion, any and all elections for U.S. federal, state, local and foreign tax matters, including any election to adjust the basis of Partnership property pursuant to Sections 734(b), 743(b) and 754 of the Code or comparable provisions of state, local or foreign law;

     (xiii) delegate any powers or responsibilities of the Managing General Partner under this Agreement as they relate to any Operating Company to the trustees, directors, or managers, as applicable, of such Operating Company.

     (c) Notwithstanding subsections (a) and (b) of this Section 4.2, the Managing General Partner shall not take any action in the name or on behalf of the Partnership which under the terms of this Agreement requires the approval or consent of the Management Board, the Advisory Committee, Partners other than the Managing General

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Partner (including, if applicable, the Non-Managing General Partner) or Fund Investors, unless the approval or consent required by this Agreement has been obtained.

     SECTION 4.3 Time Commitment .

     (a) The Managing General Partner shall, and shall cause its Affiliates and their respective employees, officers and agents to, devote to the Partnership, Operating Companies and Investments such time as shall be necessary to conduct the business and affairs of the Partnership, Operating Companies and Investments in an appropriate manner consistent with the terms of this Agreement and the Constituent Documents of each Operating Company. The Partners acknowledge that the Managing General Partner and other Affiliates of Hines and their respective employees, officers and agents may also engage in activities unrelated to the Fund and may provide services to Persons other than the Partnership, the Operating Companies or any of their Affiliates.

     (b) The Managing General Partner shall cause the Management Team to devote such time as the Managing General Partner reasonably determines is necessary to manage and operate the business affairs of Fund in an appropriate manner consistent with the terms of this Agreement.

     SECTION 4.4 Outside Investments . So long as the Fund has the capacity to make new Investments, the Managing General Partner will not and will cause each Affiliate of Hines not to make (i) any new equity investment which satisfies the Investment Guidelines (other than through an interest in the Fund) or (ii) act as a manager or the primary source of transactions on behalf of another pooled investment fund focusing on substantially the same types of investment opportunities as those targeted by the Fund; provided that such restrictions shall not apply to the following:

     (a) any investment which the Managing General Partner has decided not to make or pursue based on a good faith determination that such investment is inappropriate or inadvisable for the Fund, whether due to capacity, diversification, rate of return objectives or other considerations; provided that to the extent the Managing General Partner determines in good faith that it is desirable for the Fund to make some but not all of a particular investment, then the Fund may make such investment to such extent and the Managing General Partner or another Affiliate of Hines may co-invest with the Fund in such investment on a side-by-side basis on terms no more favorable than those applicable to the Fund’s share of the investment;