NOTE PURCHASE AGREEMENT

Exhibit 4.1

E XECUTION V ERSION

BGC P ARTNERS , L.P.

$150,000,000

Senior Notes due April 1, 2010

N OTE P URCHASE A GREEMENT

Dated as of March 31, 2008

T ABLE OF C ONTENTS

(Not a part of the Agreement)

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BGC P ARTNERS , L.P.

199 Water Street

New York, New York 10038

$150,000,000 Senior Notes due April 1, 2010

Dated as of March 31, 2008

T O EACH OF THE P URCHASERS LISTED IN THE ATTACHED

  S CHEDULE A HERETO :

Ladies and Gentlemen:

BGC P ARTNERS , L.P., a Delaware limited partnership (the “Company” ), agrees with each of the purchasers whose names appear at the end hereof (each, a “Purchaser” and, collectively, the “Purchasers” ) as follows:

S ECTION  1.        A UTHORIZATION OF N OTES .

Section 1.1.    Authorization .    The Company will authorize the issue and sale of $150,000,000 aggregate principal amount of its Senior Notes due April 1, 2010 (the “Notes,” such term to include any such notes issued in substitution therefor pursuant to Section 13 ). The Notes shall be substantially in the form set out in Exhibit 1 . Certain capitalized and other terms used in this Agreement are defined in Schedule B ; and references to a “Schedule” or an “Exhibit” are, unless otherwise specified, to a Schedule or an Exhibit attached to this Agreement. The Notes shall bear interest from the date of issue at a rate equal to the Applicable Interest Rate. Interest on the Notes shall be computed on the basis of a 360-day year of twelve 30-day months.

Section 1.2.    Change in Reserve Requirement.     (a) If on any date under applicable insurance regulations any holder of a Note is required to post reserves with respect to the Notes (the “Reserve Requirement” ) greater than the Reserve Requirement in effect immediately prior to the date of the Closing, then from and including such date to and until the Interest Reset Date, the interest rate on the Notes shall be adjusted as follows: the then Applicable Interest Rate on the Notes shall be increased by 50 basis points.

(b)    Without limiting the effectiveness of the foregoing, the holders of the Notes shall use their best efforts to notify the Company if an interest rate adjustment as described in Section 1.2(a) is in effect.

(c)    The Company shall notify each of the holders of the Notes in writing, sent in the manner provided in Section 19 , when it believes an Interest Reset Date has occurred, which written notice shall identify such Interest Reset Date. The Interest Reset Date shall be deemed to have occurred on the date identified in the Company’s notice, unless within 30 days after receipt

of such notice, any holder of a Note shall notify the Issuer that its current Reserve Requirement is greater than the Reserve Requirement in effect immediately prior to the date of the Closing, in which case the Interest Reset Date shall not have occurred and interest on the Notes shall continue to accrue as set forth in Section 1.2(a) until the Interest Reset Date.

S ECTION  2.        S ALE AND P URCHASE OF N OTES .

Section 2.1.    Background . CFLP and each of the Purchasers have heretofore entered into the Note Purchase Agreement dated as of March 15, 2005 (the “CFLP Note Agreement” ), pursuant to which CFLP has heretofore issued $250,000,000 in aggregate principal amount of its Senior Notes due April 1, 2010 (the “CFLP Notes due April 1, 2010” ).

Pursuant to that certain Note Exchange, Novation and First Amendment Agreement dated March 31, 2008 among the Company, CFLP and the Purchasers, CFLP and the Purchasers have (i) amended the CFLP Note Agreement and (ii) agreed to the surrender, termination and novation of $150,000,000 aggregate principal amount of the CFLP Notes due April 1, 2010 (the “Designated CFLP Notes due April 1, 2010” ) in exchange for $150,000,000 aggregate principal amount of the Notes.

Section 2.2.    Sale and Purchase of the Notes . Subject to the terms and conditions of this Agreement, the Company will issue and sell to each Purchaser and each Purchaser will purchase from the Company, at the Closing provided for in Section 3 , Notes in the principal amount specified opposite such Purchaser’s name in Schedule A at the purchase price of 100% of the principal amount thereof. The Purchasers’ obligations hereunder are several and not joint obligations and no Purchaser shall have any liability to any Person for the performance or non-performance of any obligation by any other Purchaser hereunder.

Section 2.3.    Affiliate Guaranties . The payment by the Company of all amounts due with respect to the Notes and the performance by the Company of its obligations under this Agreement will be absolutely and unconditionally guaranteed by (a) BGC Partners, Inc. (successor by merger of BGC Partners, LLC and eSpeed, Inc.), a Delaware corporation ( “BGC Partners” ), pursuant to the Guaranty Agreement substantially in the form of Exhibit 2.2(a) (as the same may be amended, modified, extended or renewed, the “BGC Partners Guaranty” ) and (b) Cantor Fitzgerald, L.P., a Delaware limited partnership ( “CFLP” ) pursuant to the Guaranty Agreement substantially in the form of Exhibit 2.2(b) (as the same may be amended, modified, extended or renewed, the “CFLP Guaranty” ).

S ECTION  3 .         C LOSING .

The sale and purchase of the Notes to be purchased by each Purchaser shall occur at the offices of Chapman and Cutler LLP, 111 West Monroe Street, Chicago, Illinois 60603, at 10:00 A . M . Chicago time, at a closing (the “Closing” ) on March 31, 2008. At the Closing, the Company will deliver to each Purchaser the Notes to be purchased by such Purchaser in the form of a single Note (or such greater number of Notes in denominations of at least $100,000 as such Purchaser may request) dated the date of the Closing and registered in such Purchaser’s name (or

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in the name of its nominee), against delivery by such Purchaser to the Company of Designated CFLP Notes due April 1, 2010 in the same aggregate principal amount as the Notes so purchased. If at the Closing the Company shall fail to tender such Notes to any Purchaser as provided above in this Section 3 , or any of the conditions specified in Section 4 shall not have been fulfilled to such Purchaser’s satisfaction, such Purchaser shall, at its election, be relieved of all further obligations under this Agreement, without thereby waiving any rights such Purchaser may have by reason of such failure or such nonfulfillment.

S ECTION  4.        C ONDITIONS TO C LOSING .

Each Purchaser’s obligation to purchase and pay for the Notes to be sold to such Purchaser at the Closing is subject to the fulfillment to such Purchaser’s satisfaction, prior to or at the Closing, of the following conditions:

Section 4.1.    Representations and Warranties .  (a) The representations and warranties of the Company in this Agreement shall be correct when made and at the time of the Closing.

(b)    The representations and warranties of the BGC General Partner set forth in the Closing Certificate and Agreement (the “BGC General Partner Agreement” ) attached hereto as Schedule 4.1(b) and made a part hereof shall be correct when made and at the time of Closing. Each Purchaser agrees and acknowledges, and each transferee of a Note shall be deemed to have agreed and acknowledged, that no stockholder, director, officer, employee, agent or other representative of the BGC General Partner shall have any liability in respect of or arising out of the BGC General Partner Agreement or the matters contemplated thereby.

(c)    The representations and warranties of BGC Partners set forth in the BGC Partners Guaranty shall be correct when made and at the time of Closing.

(d)    The representations and warranties of CFLP set forth in the CFLP Guaranty shall be correct when made and at the time of Closing.

Section 4.2.    Performance; No Default .     The Company shall have performed and complied with all agreements and conditions contained in this Agreement required to be performed or complied with by it prior to or at the Closing, and after giving effect to the issue and sale of the Notes, no Default or Event of Default shall have occurred and be continuing.

Section 4.3.    Compliance Certificates .

(a)     Company Officer’s Certificate .    The Company shall have delivered to such Purchaser a Company Officer’s Certificate, dated the date of the Closing, certifying that the conditions specified in Sections 4.1(a), 4.2 and 4.9 have been fulfilled.

(b)     Company Authority Certificate .    The Company shall have delivered to such Purchaser a certificate of an authorized officer, dated the date of Closing, certifying as to the resolutions attached thereto and other legal proceedings relating to the authorization, execution and delivery of the Notes and this Agreement.

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(c)     BGC General Partner Secretary’s Certificate .  The BGC General Partner shall have delivered to such Purchaser a certificate of its Secretary or Assistant Secretary, dated the date of Closing, certifying as to the resolutions attached thereto and other corporate proceedings related to the authorization, execution and delivery of the Notes, this Agreement and the BGC General Partner Agreement.

(d)     BGC Partners Secretary’s Certificate .  BGC Partners shall have delivered to such Purchaser a certificate of its Secretary or Assistant Secretary, dated the date of Closing, certifying as to the resolutions set forth in the BGC Partners Guaranty and other corporate proceedings related to the authorization, execution and delivery of the BGC Partners Guaranty.

(e)     CFLP Secretary’s Certificate .    CFLP shall have delivered to such Purchaser a certificate of CF General Partner’s Secretary or Assistant Secretary, dated the date of Closing, certifying as to the resolutions set forth in the CFLP Guaranty and other corporate proceedings related to the authorization, execution and delivery of the CFLP Guaranty.

Section 4.4.    Opinions of Counsel .  Such Purchaser shall have received opinions in form and substance satisfactory to such Purchaser, dated the date of the Closing (a) from Morgan, Lewis & Bockius LLP, counsel for the Company, BGC Partners, CFLP and the BGC General Partner, covering the matters set forth in Exhibit 4.4(a) and covering such other matters incident to the transactions contemplated hereby as such Purchaser or its counsel may reasonably request (and the Company, BGC Partners, CFLP and the BGC General Partner hereby instruct their counsel to deliver such opinion to the Purchasers) and (b) from Chapman and Cutler LLP, the Purchasers’ special counsel in connection with such transactions, substantially in the form set forth in Exhibit 4.4(b) and covering such other matters incident to such transactions as such Purchaser may reasonably request.

Section 4.5.    Purchase Permitted by Applicable Law, Etc .  On the date of the Closing such Purchaser’s purchase of Notes shall (a) be permitted by the laws and regulations of each jurisdiction to which such Purchaser is subject, without recourse to provisions (such as Section 1405(a)(8) of the New York Insurance Law) permitting limited investments by insurance companies without restriction as to the character of the particular investment, (b) not violate any applicable law or regulation (including, without limitation, Regulation T, U or X of the Board of Governors of the Federal Reserve System) and (c) not subject such Purchaser to any tax, penalty or liability under or pursuant to any applicable law or regulation, which law or regulation was not in effect on the date hereof. If requested by such Purchaser in writing at least three Business Days in advance of the date of the Closing, such Purchaser shall have received an Officer’s Certificate certifying as to such matters of fact as such Purchaser may reasonably specify to enable such Purchaser to determine whether such purchase is so permitted.

Section 4.6.    Sale of Other Notes .   Contemporaneously with the Closing, the Company shall sell to each other Purchaser, and each other Purchaser shall purchase, the Notes to be purchased by it at the Closing as specified in Schedule A .

Section 4.7.    Payment of Special Counsel Fees .    Without limiting the provisions of Section 15.1 , the Company shall have paid on or before the Closing the fees, charges and

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disbursements of the Purchasers’ special counsel referred to in Section 4.4 to the extent reflected in a statement of such counsel rendered to the Company at least one Business Day prior to the Closing.

Section 4.8.    Private Placement Number .    A Private Placement Number issued by Standard & Poor’s CUSIP Service Bureau (in cooperation with the SVO) shall have been obtained for the Notes.

Section 4.9.    Changes in Legal Structure . Neither the Company nor the BGC General Partner shall have changed its jurisdiction of organization or been a party to any merger, consolidation or other reorganization or succeeded to all or any substantial part of the liabilities of any other entity, at any time following the date of the most recent financial statements referred to in Schedule 5.5 (other than in connection with the Separation and the Merger).

Section 4.10.    Guaranties. On or prior to the date of the Closing, the BGC Partners Guaranty and the CFLP Guaranty shall each be in form and substance satisfactory to such Purchaser and its special counsel, shall have been duly executed and delivered by the parties thereto and shall be in full force and effect and such Purchaser shall have received a true, correct and complete copy thereof.

Section 4.11.     [Intentionally Omitted].

Section 4.12.    Exchange, Novation and First Amendment Agreement .    On or prior to the date of the Closing, the closing conditions set forth in Section 3 of the Exchange, Novation and First Amendment Agreement shall have been consummated to the satisfaction of the Purchasers and their special counsel and the Purchasers and their special counsel shall have received true, correct and complete copies of each of the agreements, certificates, legal opinions and other documents delivered pursuant to said Section 3.

Section 4.13.    Proceedings and Documents . All legal and other proceedings in connection with the transactions contemplated by this Agreement and all documents and instruments incident to such transactions shall be satisfactory to such Purchaser and its special counsel, and such Purchaser and its special counsel shall have received all such counterpart originals or certified or other copies of such documents as such Purchaser or such special counsel may reasonably request.

S ECTION  5 .         R EPRESENTATIONS AND W ARRANTIES OF THE C OMPANY .

The Company represents and warrants to each Purchaser that:

Section 5.1.    Organization; Power and Authority . The Company is a limited partnership duly organized, validly existing and in good standing under the laws of its jurisdiction of organization, and is duly qualified as a foreign limited partnership and is in good standing in each jurisdiction in which such qualification is required by law, other than those jurisdictions as to which the failure to be so qualified or in good standing could not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. The Company has the legal

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power and authority to own or hold under lease the properties it purports to own or hold under lease, to transact the business it transacts and proposes to transact, to execute and deliver this Agreement and the Notes and to perform the provisions hereof and thereof.

Section 5.2.    Authorization, Etc .    This Agreement and the Notes have been duly authorized by all necessary legal action on the part of the Company, and this Agreement constitutes, and upon execution and delivery thereof each Note will constitute, a legal, valid and binding obligation of the Company enforceable against the Company in accordance with its terms, except as such enforceability may be limited by (a) applicable bankruptcy, insolvency, reorganization, moratorium or other similar laws affecting the enforcement of creditors’ rights generally and (b) general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law).

Section 5.3.    Disclosure .  Since December 31, 2006, there has been no change in the financial condition, operations, business, properties or prospects of the Company or any Subsidiary except changes that individually or in the aggregate could not reasonably be expected to have a Material Adverse Effect. There is no fact known to the Company that could reasonably be expected to have a Material Adverse Effect that has not been set forth herein.

Section 5.4.    Compliance with Laws, Other Instruments, Etc .  The execution, delivery and performance by the Company of this Agreement and the Notes will not (a) contravene, result in any breach of, or constitute a default under, or result in the creation of any Lien in respect of any property of the Company or any Subsidiary under, any indenture, mortgage, deed of trust, loan, purchase or credit agreement, lease, corporate charter or by-laws, limited liability company agreement, partnership agreement or any other agreement or instrument to which the Company or any Subsidiary is bound or by which the Company or any Subsidiary or any of their respective properties may be bound or affected, (b) conflict with or result in a breach of any of the terms, conditions or provisions of any order, judgment, decree, or ruling of any court, arbitrator or Governmental Authority applicable to the Company or any Subsidiary, (c) violate any provision of any statute or other rule or regulation of any Governmental Authority applicable to the Company or any Subsidiary, or (d) require any consent or approval of the limited partners or, in the case of the general partner of the Company, any consent or approval which has not been obtained and which is not in full force and effect, the members of the BGC General Partner, the partners or stockholders of any of the Company’s Subsidiaries or any other third party, except in the case of the foregoing clauses (a) and (b), any contravention, breach, default, Lien or conflict which individually or in the aggregate could not reasonably be expected to have a Material Adverse Effect.

Section 5.5.    Governmental Authorizations, Etc .  No consent, approval or authorization of, or registration, filing or declaration with, any Governmental Authority is required in connection with the execution, delivery or performance by the Company of this Agreement or the Notes.

S ection 5.6.    Litigation; Observance of Agreements, Statutes and Orders.   (a) There are no actions, suits, investigations or proceedings pending or, to the knowledge of the Company, threatened against or affecting the Company or any Subsidiary or any property of the Company or

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any Subsidiary in any court or before any arbitrator of any kind or before or by any Governmental Authority that, individually or in the aggregate, could reasonably be expected to have a Material Adverse Effect.

(b)    Neither the Company nor any Subsidiary is in default under any term of any agreement or instrument to which it is a party or by which it is bound, or any order, judgment, decree or ruling of any court, arbitrator or Governmental Authority or is in violation of any applicable law, ordinance, rule or regulation (including without limitation Environmental Laws or the USA Patriot Act) of any Governmental Authority, which default or violation, individually or in the aggregate, could reasonably be expected to have a Material Adverse Effect.

Section 5.7.    Taxes .  The Company and its Subsidiaries have filed all tax returns that are required to have been filed in any jurisdiction, and have paid all taxes shown to be due and payable on such returns and all other taxes and assessments levied upon them or their properties, assets, income or franchises, to the extent such taxes and assessments have become due and payable and before they have become delinquent, except for any taxes and assessments (a) the amount of which is not individually or in the aggregate Material or (b) the amount, applicability or validity of which is currently being contested in good faith by appropriate proceedings and with respect to which the Company or a Subsidiary, as the case may be, has established adequate reserves in accordance with GAAP. The Company knows of no basis for any other tax or assessment that could reasonably be expected to have a Material Adverse Effect. The charges, accruals and reserves on the books of the Company and its Subsidiaries in respect of federal, state or other taxes for all fiscal periods are adequate. The federal income tax liabilities of the Company and its Subsidiaries have been finally determined (whether by reason of completed audits or the statute of limitations having run) for all fiscal years up to and including the fiscal year ended December 31, 2003.

Section 5.8.    Title to Property; Leases .  The Company and its Subsidiaries have good and sufficient title to their respective properties that individually or in the aggregate are Material, including all such properties referred to in Section 5.5 or purported to have been acquired by the Company or any Subsidiary after said date (except as sold or otherwise disposed of in the ordinary course of business), in each case free and clear of Liens prohibited by this Agreement. All leases that individually or in the aggregate are Material are valid and subsisting and are in full force and effect in all material respects.

Section 5.9.    Licenses, Permits, Etc.     (a) The Company and its Subsidiaries own or possess all licenses, permits, franchises, authorizations, patents, copyrights, proprietary software, service marks, trademarks and trade names, or rights thereto, that individually or in the aggregate are Material, without known conflict with the rights of others.

(b)    To the best knowledge of the Company, no product of the Company infringes in any Material respect any license, permit, franchise, authorization, patent, copyright, proprietary software, service mark, trademark, trade name or other right owned by any other Person.

(c)    To the best knowledge of the Company, there is no Material violation by any Person of any right of the Company or any of its Subsidiaries with respect to any patent, copyright,

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proprietary software, service mark, trademark, trade name or other right owned or used by the Company or any of its Subsidiaries.

Section 5.10.    Private Offering by the Company .  Neither the Company nor anyone acting on its behalf has offered the Notes or any similar Securities for sale to, or solicited any offer to buy any of the same from, or otherwise approached or negotiated in respect thereof with, any Person other than the Purchasers, each of which has been offered the Notes at a private sale for investment. Neither the Company nor anyone acting on its behalf has taken, or will take, any action that would subject the issuance or sale of the Notes to the registration requirements of Section 5 of the Securities Act or to the registration requirements of any securities or blue sky laws of any applicable jurisdiction.

Section 5.11.    Margin Regulations .  As the Notes are being issued in exchange for the CFLP Notes due April 1, 2010, no part of the proceeds from the sale of the Notes hereunder will be used, directly or indirectly, for the purpose of buying or carrying any margin stock within the meaning of Regulation U of the Board of Governors of the Federal Reserve System (12 CFR 221), or for the purpose of buying or carrying or trading in any securities under such circumstances as to involve the Company in a violation of Regulation X of said Board (12 CFR 224) or to involve any broker or dealer in a violation of Regulation T of said Board (12 CFR 220). Margin stock does not constitute more than 2% of the value of the consolidated assets of the Company and its Subsidiaries and the Company does not have any present intention that margin stock will constitute more than 2% of the value of such assets. As used in this Section, the terms “margin stock” and “purpose of buying or carrying” shall have the meanings assigned to them in said Regulation U.

Section 5.12.    Foreign Assets Control Regulations, Etc .  (a) The issuance of the Notes by the Company hereunder will not violate the Trading with the Enemy Act, as amended, or any of the foreign assets control regulations of the United States Treasury Department (31 CFR, Subtitle B, Chapter V, as amended) or any enabling legislation or executive order relating thereto.

(b)    Neither the Company nor any Subsidiary (i) is, or will become, a Person described or designated in the Specially Designated Nationals and Blocked Persons List of the Office of Foreign Assets Control or in Section 1 of the Anti-Terrorism Order or (ii) engages or will engage in any dealings or transactions, or is or will be otherwise associated, with any such Person. The Company and its Subsidiaries are in compliance, in all material respects, with the USA Patriot Act.

(c)    As the Notes are being issued in exchange for the CFLP Notes due April 1, 2010, no part of the proceeds from the issuance of the Notes hereunder will be used, directly or indirectly, for any payments to any governmental official or employee, political party, official of a political party, candidate for political office, or anyone else acting in an official capacity, in order to obtain, retain or direct business or obtain any improper advantage, in violation of the United States Foreign Corrupt Practices Act of 1977, as amended, assuming in all cases that such Act applies to the Company.

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Section 5.13.    Status under Certain Statutes .  Neither the Company nor any Subsidiary is subject to regulation under the Investment Company Act of 1940, as amended, the ICC Termination Act of 1995, as amended, or the Federal Power Act, as amended.

Section 5.14.    Notes Rank Pari Passu .    The obligations of the Company under this Agreement and the Notes rank at least pari passu in right of payment with all other unsecured Senior Debt (actual or contingent) of the Company, including, without limitation, all unsecured Senior Debt of the Company described in Schedule 5.15 to the BGC Partners Guaranty.

Section 5.15.    Environmental Matters .  (a) Neither the Company nor any Subsidiary has knowledge of any claim or has received any notice of any claim, and no proceeding has been instituted raising any claim against the Company or any of its Subsidiaries or any of their respective real properties now or formerly owned, leased or operated by any of them or other assets, alleging any damage to the environment or violation of any Environmental Laws, except, in each case, such as could not reasonably be expected to result in a Material Adverse Effect.

(b)    Neither the Company nor any Subsidiary has knowledge of any facts which would give rise to any claim, public or private, of violation of Environmental Laws or damage to the environment emanating from, occurring on or in any way related to real properties now or formerly owned, leased or operated by any of them or to other assets or their use, except, in each case, such as could not reasonably be expected to result in a Material Adverse Effect.

(c)    Neither the Company nor any Subsidiary has stored any Hazardous Materials on real properties now or formerly owned, leased or operated by any of them or has disposed of any Hazardous Materials in a manner contrary to any Environmental Laws in each case in any manner that could reasonably be expected to result in a Material Adverse Effect.

(d)    All buildings on all real properties now owned, leased or operated by the Company or any Subsidiary are in compliance with applicable Environmental Laws, except where failure to comply could not reasonably be expected to result in a Material Adverse Effect.

S ECTION  6.        R EPRESENTATIONS OF THE P URCHASER .

Section 6.1.    Purchase for Investment .  (a) Each Purchaser severally represents that it is acquiring the Notes for its own account or for one or more separate accounts maintained by such Purchaser or for the account of one or more pension or trust funds and not with a view to the distribution thereof; provided that the disposition of such Purchaser’s or their property shall at all times be within such Purchaser’s or their control. Each Purchaser understands that the Notes have not been registered under the Securities Act and may be resold only if registered pursuant to the provisions of the Securities Act or if an exemption from registration is available, except under circumstances where neither such registration nor such an exemption is required by law, and that the Company is not required to register the Notes.

(b)    Each Purchaser understands and agrees that it will not transfer the Notes or any part or portion thereof held by it (i) to any Person who is not an Institutional Investor or who is a Competitor or (ii) in violation of applicable law.

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Section 6.2.    Source of Funds .  Each Purchaser severally represents that it will pay the purchase price of the Notes with Designated CFLP Notes due April 1, 2010. Each Purchaser severally further represents that at least one of the following statements was an accurate representation as to each source of funds (a “Source” ) used by such Purchaser to pay the purchase price of the Designated CFLP Notes due April 1, 2010 exchanged by such Purchaser hereunder:

(a) the Purchaser is an insurance company and the Source is an “insurance company general account” (as the term is defined in the United States Department of Labor’s Prohibited Transaction Exemption ( “PTE” ) 95-60) in respect of which the reserves and liabilities (as defined by the annual Statement for Life Insurance Companies approved by the National Association of Insurance Commissioners (the “NAIC Annual Statement” )) for the general account contract(s) held by or on behalf of any employee benefit plan together with the amount of the reserves and liabilities for the general account contract(s) held by or on behalf of any other employee benefit plans maintained by the same employer (or affiliate thereof as defined in PTE 95-60) or by the same employee organization in the general account do not exceed ten percent (10%) of the total reserves and liabilities of the general account (exclusive of separate account liabilities) plus surplus as set forth in the NAIC Annual Statement filed with such Purchaser’s state of domicile; or

(b) the Source is a separate account that is maintained solely in connection with such Purchaser’s fixed contractual obligations under which the amounts payable, or credited, to any employee benefit plan (or its related trust) that has any interest in such separate account (or to any participant or beneficiary of such plan (including any annuitant)) are not affected in any manner by the investment performance of the separate account; or

(c) the Source is either (i) an insurance company pooled separate account, within the meaning of PTE 90-1, or (ii) a bank collective investment fund, within the meaning of the PTE 91-38 and, except as have been disclosed by such Purchaser to the Company in writing pursuant to this clause (c), no employee benefit plan or group of plans maintained by the same employer or employee organization beneficially owns more than 10% of all assets allocated to such pooled separate account or collective investment fund; or

(d) the Source constitutes assets of an “investment fund” (within the meaning of Part V of the QPAM Exemption) managed by a “qualified professional asset manager” or “QPAM” (within the meaning of Part V of the QPAM Exemption), no employee benefit plan’s assets that are included in such investment fund, when combined with the assets of all other employee benefit plans established or maintained by the same employer or by an affiliate (within the meaning of Section V(c)(1) of the QPAM Exemption) of such employer or by the same employee organization and managed by such QPAM, exceed 20% of the total client assets managed by such QPAM, the conditions of Part l(c) and (g) of the QPAM Exemption are satisfied, neither the QPAM nor a Person controlling or controlled by the QPAM (applying the definition of “control” in Section V(e) of the

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QPAM Exemption) owns a 5% or more interest in the Company and (i) the identity of such QPAM and (ii) the names of all employee benefit plans whose assets are included in such investment fund have been disclosed to the Company in writing pursuant to this clause (d); or

(e) the Source constitutes assets of a “plan(s)” (within the meaning of Section IV of PTE 96-23 (the “INHAM Exemption” )) managed by an “in-house asset manager” or “INHAM” (within the meaning of Part IV of the INHAM exemption), the conditions of Part I(a), (g) and (h) of the INHAM Exemption are satisfied, neither the INHAM nor a Person controlling or controlled by the INHAM (applying the definition of “control” in Section IV(d) of the INHAM Exemption) owns a 5% or more interest in the Company and (i) the identity of such INHAM and (ii) the name(s) of the employee benefit plan(s) whose assets constitute the Source have been disclosed to the Company in writing pursuant to this clause (e); or

(f) the Source is a governmental plan that is covered neither by ERISA nor Section 4975 of the Code; or

(g) the Source is one or more employee benefit plans, or a separate account or trust fund comprised of one or more employee benefit plans, each of which has been identified to the Company in writing pursuant to this clause (g); or

(h) the Source does not include assets of any employee benefit plan, other than a plan exempt from the coverage of ERISA or which is not subject to Section 4975 of the Code.

As used in this Section 6.2 , the terms “employee benefit plan”, “governmental plan” and “separate account” shall have the respective meanings assigned to such terms in Section 3 of ERISA.

S ECTION  7.    [R ESERVED ].

S ECTION  8.    P REPAYMENT OF THE N OTES .

Section 8.1.    Required Prepayments .  No regularly scheduled prepayment of the principal of the Notes is required prior to the final maturity date thereof.

Section 8.2.    Optional Prepayments with Make-Whole Amount .    The Company may, at its option, upon notice as provided below, prepay at any time all, or from time to time any part of, the Notes, in an amount not less than 10% of the aggregate principal amount of the Notes then outstanding in the case of a partial prepayment, at 100% of the principal amount so prepaid, together with interest accrued thereon to the date of such prepayment, and the Make-Whole Amount determined for the prepayment date with respect to such principal amount. The Company will give each holder of Notes written notice of each optional prepayment under this Section 8.2 not less than 30 days and not more than 60 days prior to the date fixed for such

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prepayment. Each such notice shall specify such date (which shall be a Business Day), the aggregate principal amount of the Notes to be prepaid on such date, the principal amount of each Note held by such holder to be prepaid (determined in accordance with Section 8.4 ), and the interest to be paid on the prepayment date with respect to such principal amount being prepaid, and shall be accompanied by a certificate of a Senior Financial Officer as to the estimated Make-Whole Amount due in connection with such prepayment (calculated as if the date of such notice were the date of the prepayment), setting forth the details of such computation. Two Business Days prior to such prepayment, the Company shall deliver to each holder of Notes a certificate of a Senior Financial Officer specifying the calculation of such Make-Whole Amount as of the specified prepayment date.

Section 8.3.    Change in Control .    (a)  Notice of Change in Control or Control Event. The Company will, within five Business Days after any Responsible Officer has knowledge of the occurrence of any Change in Control or Control Event (or thirty Business Days in the case of the death of Howard Lutnick that gives rise to a Control Event), give written notice of such Change in Control or Control Event to each holder of Notes unless notice in respect of such Change in Control (or the Change in Control contemplated by such Control Event) shall have been given pursuant to subparagraph (b) of this Section 8.3 . If a Change in Control has occurred, such notice shall contain and constitute an offer to prepay Notes as described in subparagraph (c) of this Section 8.3 and shall be accompanied by the certificate described in subparagraph (g) of this Section 8.3 .

(b)     Condition to Company Action.     The Company will not take any action that consummates or finalizes a Change in Control unless (i) at least 30 days prior to such action it shall have given to each holder of Notes written notice containing and constituting an offer to prepay Notes as described in subparagraph (c) of this Section 8.3 , accompanied by the certificate described in subparagraph (g) of this Section 8.3 , and (ii) contemporaneously with such action, it prepays all Notes required to be prepaid in accordance with this Section 8.3 .

(c)     Offer to Prepay Notes.     The offer to prepay Notes contemplated by subparagraphs (a) and (b) of this Section 8.3 shall be an offer to prepay, in accordance with and subject to this Section 8.3 , all, but not less than all, the Notes held by each holder (in this case only, “holder” in respect of any Note registered in the name of a nominee for a disclosed beneficial owner shall mean such beneficial owner) on a date (which date shall be a Business Day) specified in such offer (the “Proposed Prepayment Date” ). If such Proposed Prepayment Date is in connection with an offer contemplated by subparagraph (a) of this Section 8.3 , such date shall be not less than 30 days and not more than 120 days after the date of such offer (if the Proposed Prepayment Date shall not be specified in such offer, the Proposed Prepayment Date shall be the first Business Day after the 45th day after the date of such offer).

(d)     Rejection.     A holder of Notes may accept the offer to prepay made pursuant to this Section 8.3 by causing a notice of such acceptance to be delivered to the Company not later than 15 days after receipt by such holder of the most recent offer of prepayment. A failure by a holder of Notes to respond to an offer to prepay made pursuant to this Section 8.3 shall be deemed to constitute a rejection of such offer by such holder.

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(e)     Prepayment.     Prepayment of the Notes to be prepaid pursuant to this Section 8.3 shall be at 100% of the principal amount of such Notes, together with interest on such Notes accrued to the date of prepayment, but without Make-Whole Amount or other premium. The prepayment shall be made on the Proposed Prepayment Date except as provided in subparagraph (f) of this Section 8.3 .

(f)     Deferral Pending Change in Control.     The obligation of the Company to prepay Notes pursuant to the offers required by subparagraph (c) and accepted in accordance with subparagraph (d) of this Section 8.3 is subject to the occurrence of the Change in Control in respect of which such offers and acceptances shall have been made. In the event that such Change in Control has not occurred on the Proposed Prepayment Date in respect thereof, the prepayment shall be deferred until, and shall be made on, the date on which such Change in Control occurs. To the extent reasonably practicable, the Company shall keep each holder of Notes reasonably and timely informed of (i) any such deferral of the date of prepayment, (ii) the date on which such Change in Control and the prepayment are expected to occur, and (iii) any determination by the Company that efforts to effect such Change in Control have ceased or been abandoned (in which case the offers and acceptances made pursuant to this Section 8.3 in respect of such Change in Control shall be deemed rescinded).

(g)     Officer’s Certificate.     Each offer to prepay the Notes pursuant to this Section 8.3 shall be accompanied by a certificate, executed by a Senior Financial Officer of the Company and dated the date of such offer, specifying: (i) the Proposed Prepayment Date; (ii) that such offer is made pursuant to this Section 8.3 ; (iii) the principal amount of each Note offered to be prepaid; (iv) the interest that would be due on each Note offered to be prepaid, accrued to the Proposed Prepayment Date; (v) that the conditions of this Section 8.3 have been fulfilled; and (vi) in reasonable detail, the nature and date or proposed date of the Change in Control.

(h)     Certain Definitions.      “Change in Control” shall be deemed to have occurred if (i) any person or “group” (within the meaning of Section 13(d) or 14(d) of the Securities Exchange Act of 1934, as amended) (other than the Control Group) shall have acquired the beneficial ownership of 20% or more of any outstanding class of Capital Stock having ordinary voting power in the election of directors of CF General Partner or (ii) the Control Group shall cease to own and control, of record and beneficially, Capital Stock of CF General Partner possessing the voting power under normal circumstances to cast 70% or more of the total votes entitled to be cast for the election of directors of CF General Partner or (iii) the Control Group shall no longer have the voting power or the contractual right to elect a majority of CF General Partner’s directors or (iv) CF General Partner shall no longer be the sole managing general partner of CFLP; provided, however, that no Change in Control shall be deemed to have occurred under the foregoing clauses (i), (ii) or (iii) so long as within thirty (30) days of any of the foregoing events, a majority of the board of directors of CF General Partner shall consist of at least two then current Permitted Executives who were also Permitted Executives immediately prior to the Change in Control. For purposes of this Section 8(h) and subject to Section 8(i) , the term “Permitted Executives” means, at any time, Stuart Fraser, Lee Amaitis, Philip Marber, Stephen Merkel, Kevin Foley, Shaun Lynn and Daniel LaVecchia.

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“Control Group” means, subject to Section 8(i) : Howard W. Lutnick so long as he is alive and, upon his death, (a) his heirs or estate or both and (b) any of Stuart Fraser, Lee Amaitis, Philip Marber, Stephen Merkel, Kevin Foley, Shaun Lynn and Daniel LaVecchia or a trust controlled by one or more of the foregoing and Edie Lutnick and/or Allison Lutnick for the benefit of the heirs of Howard W. Lutnick.

“Control Event” means:

(i) the execution by the Company or any of its Subsidiaries or Affiliates of any agreement with respect to any proposed transaction or event or series of transactions or events which, individually or in the aggregate, may reasonably be expected to result in a Change in Control, or

(ii) the execution of any written agreement which, when fully performed by the parties thereto, would result in a Change in Control.

(i) At such time that the Company shall deliver to each holder of the Notes evidence that (I) the Guarantee Agreement, dated as of August 27, 2004, between CFLP and JPMorgan Chase Bank, N.A. ( “JPMorgan” ), as amended, (II) the Guarantee Agreement, dated as of December 17, 2004, between CFLP and JP Morgan, as amended, (III) the Guarantee Agreement (Second 2004 Series), dated as of December 17, 2004, between CFLP and JPMorgan, as amended, and (IV) the Guarantee Agreement, dated as of March 31, 2005, between CFLP and JPMorgan, as amended, shall have each been amended to reflect the following definitions of “Permitted Executives” and “Control Group,” then, for purposes of Section 8(h) , the same terms shall be automatically amended to read as follows:

“Permitted Executives” shall mean, at any time, any then current chairman, vice chairman, chief executive officer, chief operating officer, chief legal officer, and chief financial officer (including for this purpose any of multiple persons holding such offices as “co” officers), and the deputies of such officers, of any of CFLP, CF General Partner, BGC Partners, the Company, Cantor Fitzgerald Securities or Cantor Fitzgerald & Co.

“Control Group” shall mean: Howard W. Lutnick or a revocable trust controlled by him so long as he is alive and, upon his death (a) his heirs or estate or both and (b) any one or more Permitted Executives or a trust controlled by (i) any one or more Permitted Executives and (ii) Edie Lutnick and/or Allison Lutnick for the benefit of the heirs of Howard W. Lutnick.

(j) All calculations contemplated in this Section 8.3 involving the Capital Stock of any Person shall be made with the assumption that all convertible Securities of such Person then outstanding and all convertible Securities issuable upon the exercise of any warrants, options and other rights outstanding at such time were converted at such time and that all options, warrants and similar rights to acquire shares of Capital Stock of such Person were exercised at such time.

Section 8.4.    Allocation of Partial Prepayments .    In the case of each partial prepayment of the Notes pursuant to Section 8.2 , the principal amount of the Notes to be prepaid shall be allocated among all of the Notes at the time outstanding in proportion, as nearly as practicable, to

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the respective unpaid principal amounts thereof not theretofore called for prepayment. All prepayments made pursuant to Section 8.3 shall be applied only to the Notes of the holders who have elected to participate in such prepayment.

Section 8.5.    Maturity; Surrender, Etc .    In the case of each prepayment of Notes pursuant to this Section 8 , the principal amount of each Note to be prepaid shall mature and become due and payable on the date fixed for such prepayment (which shall be a Business Day), together with interest on such principal amount accrued to such date and the applicable Make-Whole Amount, if any. From and after such date, unless the Company shall fail to pay such principal amount when so due and payable, together with the interest and Make-Whole Amount, if any, as aforesaid, interest on such principal amount shall cease to accrue. Any Note paid or prepaid in full shall be surrendered to the Company and cancelled and shall not be reissued, and no Note shall be issued in lieu of any prepaid principal amount of any Note.

Section 8.6.    Purchase of Notes .    The Company will not and will not permit any Affiliate that it Controls to purchase, redeem, prepay or otherwise acquire, directly or indirectly, any of the outstanding Notes except upon the payment or prepayment of the Notes in accordance with the terms of this Agreement and the Notes. The Company will promptly cancel all Notes acquired by it or any Affiliate pursuant to any payment, prepayment or purchase of Notes pursuant to any provision of this Agreement and no Notes may be issued in substitution or exchange for any such Notes.

Section 8.7.    Make-Whole Amount .    The term “Make-Whole Amount” means, with respect to any Note, an amount equal to the excess, if any, of the Discounted Value of the Remaining Scheduled Payments with respect to the Called Principal of such Note over the amount of such Called Principal; provided that the Make-Whole Amount may in no event be less than zero. For the purposes of determining the Make-Whole Amount, the following terms have the following meanings:

“Called Principal” means, with respect to any Note, the principal of such Note that is to be prepaid pursuant to Section 8.2 or has become or is declared to be immediately due and payable pursuant to Section 12.1 , as the context requires.

“Discounted Value” means, with respect to the Called Principal of any Note, the amount obtained by discounting all Remaining Scheduled Payments with respect to such Called Principal from their respective scheduled due dates to the Settlement Date with respect to such Called Principal, in accordance with accepted financial practice and at a discount factor (applied on the same periodic basis as that on which interest on the Notes is payable) equal to the Reinvestment Yield with respect to such Called Principal.

“Reinvestment Yield” means, with respect to the Called Principal of any Note, the sum of (A) .50% plus (B) the yield to maturity implied by (i) the yields reported as of 10:00 a.m. (New York City time) on the second Business Day preceding the Settlement Date with respect to such Called Principal, on the display designated as “Page PX1” (or such other display as may replace Page PX1 on Bloomberg Financial Markets (“Bloomberg”) or, if Page PX1 (or its successor screen on Bloomberg) is unavailable, the

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Telerate Access Service screen which corresponds most closely to Page PX1 for the most recently issued actively traded U.S. Treasury securities having a maturity equal to the Remaining Average Life of such Called Principal as of such Settlement Date, or (ii) if such yields are not reported as of such time or the yields reported as of such time are not ascertainable (including by way of interpolation), the Treasury Constant Maturity Series Yields reported, for the latest day for which such yields have been so reported as of the second Business Day preceding the Settlement Date with respect to such Called Principal, in Federal Reserve Statistical Release H.15 (519) (or any comparable successor publication) for actively traded U.S. Treasury securities having a constant maturity equal to the Remaining Average Life of such Called Principal as of such Settlement Date. Such implied yield will be determined, if necessary, by (a) converting U.S. Treasury bill quotations to bond-equivalent yields in accordance with accepted financial practice and (b) interpolating linearly between (1) the actively traded U.S. Treasury security with the maturity closest to and greater than such Remaining Average Life and (2) the actively traded U.S. Treasury security with the maturity closest to and less than such Remaining Average Life. The Reinvestment Yield shall be rounded to the number of decimal places as appears in the coupon of the applicable Note.

“Remaining Average Life” means, with respect to any Called Principal, the number of years (calculated to the nearest one-twelfth year) obtained by dividing (a) such Called Principal into (b) the sum of the products obtained by multiplying (i) the principal component of each Remaining Scheduled Payment with respect to such Called Principal by (ii) the number of years (calculated to the nearest one-twelfth year) that will elapse between the Settlement Date with respect to such Called Principal and the scheduled due date of such Remaining Scheduled Payment.

“Remaining Scheduled Payments” means, with respect to the Called Principal of any Note, all payments of such Called Principal and interest thereon that would be due after the Settlement Date with respect to such Called Principal if no payment of such Called Principal were made prior to its scheduled due date; provided that if such Settlement Date is not a date on which interest payments are due to be made under the terms of the Notes, then the amount of the next succeeding scheduled interest payment will be reduced by the amount of interest accrued to such Settlement Date and required to be paid on such Settlement Date pursuant to Section 8.2 or 12.1 . For the avoidance of doubt, the Applicable Interest Rate then in effect shall be used in connection with any computation of the Remaining Scheduled Payments.

“Settlement Date” means, with respect to the Called Principal of any Note, the date on which such Called Principal is to be prepaid pursuant to Section 8.2 or has become or is declared to be immediately due and payable pursuant to Section 12.1 , as the context requires.

S ECTION  9.    A FFIRMATIVE C OVENANTS .

The Company covenants that so long as any of the Notes are outstanding:

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Section 9.1.    Compliance with Law .    The Company will, and will cause each of its Subsidiaries to, comply with all laws, ordinances or governmental rules or regulations to which each of them is subject, including, without limitation, ERISA, the USA Patriot Act and Environmental Laws, and will obtain and maintain in effect all licenses, certificates, permits, franchises and other governmental authorizations necessary to the ownership of their respective properties or to the conduct of their respective businesses, in each case to the extent necessary to ensure that non-compliance with such laws, ordinances or governmental rules or regulations or failures to obtain or maintain in effect such licenses, certificates, permits, franchises and other governmental authorizations could not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

Section 9.2.    Insurance .    The Company will, and will cause each of its Subsidiaries to, maintain, with financially sound and reputable insurers, insurance with respect to their respective properties and businesses against such casualties and contingencies, of such types, on such terms and in such amounts (including deductibles, co-insurance and self-insurance, if adequate reserves are maintained with respect thereto) as is customary in the case of entities of established reputations engaged in the same or a similar business and similarly situated and the failure of which to so maintain would have a Material Adverse Effect.

Section 9.3.    Maintenance of Properties .    The Company will, and will cause each of its Subsidiaries to, maintain and keep, or cause to be maintained and kept, their respective properties in good repair, working order and condition (other than ordinary wear and tear), so that the business carried on in connection therewith may be properly conducted at all times; provided that this Section shall not prevent the Company or any Subsidiary from discontinuing the operation and the maintenance of any of its properties if such discontinuance is desirable in the conduct of its business and the Company has concluded that such discontinuance could not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

Section 9.4.    Payment of Taxes and Claims .    The Company will, and will cause each of its Subsidiaries to, file all tax returns required to be filed in any jurisdiction and to pay and discharge all taxes shown to be due and payable on such returns and all other taxes, assessments, governmental charges, or levies imposed on them or any of their properties, assets, income or franchises, to the extent such taxes and assessments have become due and payable and before they have become delinquent and all claims for which sums have become due and payable that have or might become a Lien on properties or assets of the Company or any Subsidiary; provided that neither the Company nor any Subsidiary need pay any such tax or assessment or claims or file any such tax return if (a) the amount, applicability or validity thereof is contested by the Company or such Subsidiary on a timely basis in good faith and in appropriate proceedings, and the Company or a Subsidiary has established adequate reserves therefor in accordance with GAAP on the books of the Company or such Subsidiary or (b) the nonpayment of all such taxes, assessments and claims in the aggregate or failure to file such tax returns could not reasonably be expected to have a Material Adverse Effect.

Section 9.5.    Legal Existence, Etc .    Subject to Section 10.1 , the Company will at all times preserve and keep in full force and effect its existence as a limited partnership and its status as not being taxable as a corporation for U.S. federal income tax purposes. Subject to Sections 8.4

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and 8.5 of the BGC Partners Guaranty, the Company will at all times preserve and keep in full force and effect the legal existence of each of its Subsidiaries (unless merged into the Company or a Wholly-owned Subsidiary) and all rights and franchises of the Company and its Subsidiaries unless, in the good faith judgment of the Company, the termination of or failure to preserve and keep in full force and effect such legal existence, right or franchise could not, individually or in the aggregate, have a Material Adverse Effect.

Section 9.6.    Notes to Rank Pari Passu.     The Notes and all other obligations under this Agreement of the Company are and at all times shall rank at least pari passu in right of payment with all other present and future unsecured Senior Debt (actual or contingent) of the Company.

Section 9.7.    Books and Records .    The Company will, and will cause each of its Subsidiaries to, maintain proper books of record and account in conformity with GAAP and all applicable requirements of any Governmental Authority having legal or regulatory jurisdiction over the Company, or such Subsidiary, as the case may be.

S ECTION  10.        N EGATIVE C OVENANTS .

The Company covenants that so long as any of the Notes are outstanding:

Section 10.1.    Mergers, Consolidations, Etc.     The Company will not consolidate with or be a party to a merger with any other Person, or sell, lease or otherwise dispose of all or substantially all of its assets; provided that:

(a)    the Company may consolidate or merge with or into any other Person if (i) the corporation, limited liability company or other legal entity which results from such consolidation or merger (the “Surviving Person” ) is organized under the laws of any state of the United States or the District of Columbia, (ii) the due and punctual payment of the principal of and premium, if any, and interest on all of the Notes, according to their tenor, and the due and punctual performance and observation of all of the covenants in the Notes and this Agreement to be performed or observed by the Company are expressly assumed in writing by the Surviving Person and the Surviving Person shall furnish to the holders of the Notes an opinion of counsel satisfactory to the Required Holders to the effect that the instrument of assumption has been duly authorized, executed and delivered and constitutes the legal, valid and binding contract and agreement of the Surviving Person enforceable in accordance with its terms, except as enforcement of such terms may be limited by bankruptcy, insolvency, reorganization, moratorium and similar laws affecting the enforcement of creditors’ rights generally and by general equitable principles, (iii) BGC Partners, CFLP and any Subsidiary Guarantor shall confirm in writing its obligations under the BGC Partners Guaranty, the CFLP Guaranty or the Subsidiary Guaranty, as the case may be, and (iv) at the time of such consolidation or merger and immediately after giving effect thereto, no Default or Event of Default would exist; and

(b)    the Company may sell or otherwise dispose of all or substantially all of its assets to any Person for consideration which represents the fair market value of such

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assets (as determined in good faith by a Senior Financial Officer of the Company at the time of such sale or other disposition if (i) the acquiring Person (the “Acquiring Person” ) is a corporation, partnership or limited liability company organized under the laws of any state of the United States or the District of Columbia, (ii) the due and punctual payment of the principal of and premium, if any, and interest on all the Notes, according to their tenor, and the due and p