Exhibit 4.3 

 

 

GUARANTEE AGREEMENT

by and between

ENTERPRISE FINANCIAL SERVICES
CORP

and

WILMINGTON TRUST
COMPANY

Dated as of December 12, 2008








GUARANTEE
AGREEMENT

     This GUARANTEE AGREEMENT (this
“Guarantee”), dated as of December 12, 2008, is executed and delivered by
Enterprise Financial Services Corp, a Delaware corporation (the “Guarantor”),
and Wilmington Trust Company, a Delaware banking corporation, as trustee (the
“Guarantee Trustee”), for the benefit of the Holders (as defined herein) from
time to time of the Capital Securities (as defined herein) of EFSC Capital Trust
VIII, a Delaware statutory trust (the “Issuer”). 

     WHEREAS, pursuant to an Amended and
Restated Declaration of Trust No. 2 (the “Declaration”), dated as of the date
hereof among Wilmington Trust Company, not in its individual capacity but solely
as institutional trustee, the administrators of the Issuer named therein, the
Guarantor, as sponsor, and the holders from time to time of undivided beneficial
interests in the assets of the Issuer, the Issuer is issuing on the date hereof
those undivided beneficial interests, having an aggregate liquidation amount of
$25,000,000.00 (the “Capital Securities”); and 

     WHEREAS, as incentive for the
Holders to purchase the Capital Securities, the Guarantor desires irrevocably
and unconditionally to agree, to the extent set forth in this Guarantee, to pay
to the Holders of Capital Securities the Guarantee Payments (as defined herein)
and to make certain other payments on the terms and conditions set forth herein;


     NOW, THEREFORE, in consideration of
the purchase by each Holder of the Capital Securities, which purchase the
Guarantor hereby agrees shall benefit the Guarantor, the Guarantor executes and
delivers this Guarantee for the benefit of the Holders. 

ARTICLE I 

DEFINITIONS AND INTERPRETATION


     Section 1.1.
Definitions and
Interpretation. In this Guarantee,
unless the context otherwise requires: 

     (a) capitalized terms used in this
Guarantee but not defined in the preamble above have the respective meanings
assigned to them in this Section 1.1; 

     (b) a term defined anywhere in this
Guarantee has the same meaning throughout; 

     (c) all references to “the
Guarantee” or “this Guarantee” are to this Guarantee as modified, supplemented
or amended from time to time; 

     (d) all references in this Guarantee
to “Articles” or “Sections” are to Articles or Sections of this Guarantee,
unless otherwise specified; 

     (e) terms defined in the Declaration
as at the date of execution of this Guarantee have the same meanings when used
in this Guarantee, unless otherwise defined in this Guarantee or unless the
context otherwise requires; and 




     (f) a reference to the singular
includes the plural and vice versa.

     “Affiliate” has the same meaning as
given to that term in Rule 405 of the Securities Act of 1933, as amended, or any
successor rule thereunder. 

     “Beneficiaries” means any Person to
whom the Issuer is or hereafter becomes indebted or liable. 

     “Capital Securities” has the meaning
set forth in the recitals to this Guarantee. 

     “Common Securities” means the common
securities issued by the Issuer to the Guarantor pursuant to the Declaration.


     “Corporate Trust Office” means the
office of the Guarantee Trustee at which the corporate trust business of the
Guarantee Trustee shall, at any particular time, be principally administered,
which office at the date of execution of this Guarantee is located at Rodney
Square North, 1100 North Market Street, Wilmington, Delaware 19890-1600,
Attention: Corporate Trust Administration. 

     “Covered Person” means any Holder of
Capital Securities. 

     “Debentures” means the debt securities
of the Guarantor designated the Convertible Junior Subordinated Deferrable
Interest Debentures due 2038 held by the Institutional Trustee (as defined in
the Declaration) of the Issuer. 

     “Declaration Event of Default” means an
“Event of Default” as defined in the Declaration. 

     “Event of Default” has the meaning set
forth in Section 2.4(a). 

     “Guarantee Payments” means the
following payments or distributions, without duplication, with respect to the
Capital Securities, to the extent not paid or made by the Issuer: (i) any
accrued and unpaid Distributions (as defined in the Declaration) which are
required to be paid on such Capital Securities to the extent the Issuer shall
have funds available therefor, (ii) the Redemption Price to the extent the
Issuer has funds available therefor, with respect to any Capital Securities
called for redemption by the Issuer, (iii) the Redemption Price to the extent
the Issuer has funds available therefor, with respect to Capital Securities
redeemed upon the occurrence of a Special Event, and (iv) upon a voluntary or
involuntary liquidation, dissolution, winding-up or termination of the Issuer
(other than in connection with the distribution of Debentures to the Holders of
the Capital Securities in exchange therefor as provided in the Declaration), the
lesser of (a) the aggregate of the liquidation amount and all accrued and unpaid
Distributions on the Capital Securities to the date of payment, to the extent
the Issuer shall have funds available therefor, and (b) the amount of assets of
the Issuer remaining available for distribution to Holders in liquidation of the
Issuer (in either case, the “Liquidation Distribution”). 

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     “Guarantee Trustee” means Wilmington
Trust Company, until a Successor Guarantee Trustee has been appointed and has
accepted such appointment pursuant to the terms of this Guarantee and thereafter
means each such Successor Guarantee Trustee. 

     “Guarantor” means Enterprise Financial
Services Corp and each of its successors and assigns. 

     “Holder” means any holder, as
registered on the books and records of the Issuer, of any Capital Securities;
provided, however, that, in determining whether the Holders of the requisite
percentage of Capital Securities have given any request, notice, consent or
waiver hereunder,

     “Holder” shall not include the
Guarantor or any Affiliate of the Guarantor. 

     “Indemnified Person” means the
Guarantee Trustee, any Affiliate of the Guarantee Trustee, or any officers,
directors, shareholders, members, partners, employees, representatives,
nominees, custodians or agents of the Guarantee Trustee. 

     “Indenture” means the Indenture dated
as of the date hereof between the Guarantor and Wilmington Trust Company, not in
its individual capacity but solely as trustee, and any indenture supplemental
thereto pursuant to which the Debentures are to be issued to the institutional
trustee of the Issuer. 

     “Issuer” has the meaning set forth in
the opening paragraph to this Guarantee. 

     “Liquidation Distribution” has the
meaning set forth in the definition of “Guarantee Payments” herein. 

     “Majority in liquidation amount of the Capital Securities” means Holder(s) of outstanding Capital Securities, voting
together as a class, but separately from the holders of Common Securities, of
more than 50% of the aggregate liquidation amount (including the stated amount
that would be paid on redemption, liquidation or otherwise, plus accrued and
unpaid Distributions to the date upon which the voting percentages are
determined) of all Capital Securities then outstanding. 

     “Obligations” means any costs, expenses
or liabilities (but not including liabilities related to taxes) of the Issuer
other than obligations of the Issuer to pay to holders of any Trust Securities
the amounts due such holders pursuant to the terms of the Trust Securities.


     “Officer’s Certificate” means, with
respect to any Person, a certificate signed by one Authorized Officer of such
Person. Any Officer’s Certificate delivered with respect to compliance with a
condition or covenant provided for in this Guarantee shall include: 

     (a) a statement that the officer
signing the Officer’s Certificate has read the covenant or condition and the
definitions relating thereto; 

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     (b) a brief statement of the nature
and scope of the examination or investigation undertaken by the officer in
rendering the Officer’s Certificate; 

     (c) a statement that the officer has
made such examination or investigation as, in such officer’s opinion, is
necessary to enable such officer to express an informed opinion as to whether or
not such covenant or condition has been complied with; and 

     (d) a statement as to whether, in
the opinion of the officer, such condition or covenant has been complied with.



     “Person” means a legal person,
including any individual, corporation, estate, partnership, joint venture,
association, joint stock company, limited liability company, trust,
unincorporated association, or government or any agency or political subdivision
thereof, or any other entity of whatever nature. 

     “Redemption Price” has the meaning set
forth in the Indenture. 

     “Responsible Officer” means, with
respect to the Guarantee Trustee, any officer within the Corporate Trust Office
of the Guarantee Trustee including any Vice President, Assistant Vice President,
Secretary, Assistant Secretary or any other officer of the Guarantee Trustee
customarily performing functions similar to those performed by any of the above
designated officers and also, with respect to a particular corporate trust
matter, any other officer to whom such matter is referred because of that
officer’s knowledge of and familiarity with the particular subject. 

     “Special Event” has the meaning set
forth in the Indenture. 

     “Successor Guarantee Trustee” means a
successor Guarantee Trustee possessing the qualifications to act as Guarantee
Trustee under Section 3.1. 

     “Trust Securities” means the Common
Securities and the Capital Securities. 

ARTICLE II

POWERS, DUTIES AND RIGHTS OF
GUARANTEE TRUSTEE 

     Section 2.1.
Powers and Duties of the
Guarantee Trustee. 

     (a) This Guarantee shall be held by
the Guarantee Trustee for the benefit of the Holders of the Capital Securities,
and the Guarantee Trustee shall not transfer this Guarantee to any Person except
a Holder of Capital Securities exercising his or her rights pursuant to Section
4.4(b) or to a Successor Guarantee Trustee on acceptance by such Successor
Guarantee Trustee of its appointment to act as Successor Guarantee Trustee. The
right, title and interest of the Guarantee Trustee shall automatically vest in
any Successor Guarantee Trustee, and such vesting and cessation of title shall
be effective whether or not conveyancing documents have been executed and
delivered pursuant to the appointment of such Successor Guarantee Trustee.


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     (b) If an Event of Default actually
known to a Responsible Officer of the Guarantee Trustee has occurred and is
continuing, the Guarantee Trustee shall enforce this Guarantee for the benefit
of the Holders of the Capital Securities. 

     (c) The Guarantee Trustee, before
the occurrence of any Event of Default and after curing all Events of Default
that may have occurred, shall undertake to perform only such duties as are
specifically set forth in this Guarantee, and no implied covenants shall be read
into this Guarantee against the Guarantee Trustee. In case an Event of Default
has occurred (that has not been waived pursuant to Section 2.4) and is actually
known to a Responsible Officer of the Guarantee Trustee, the Guarantee Trustee
shall exercise such of the rights and powers vested in it by this Guarantee, and
use the same degree of care and skill in its exercise thereof, as a prudent
person would exercise or use under the circumstances in the conduct of his or
her own affairs. 

     (d) No provision of this Guarantee
shall be construed to relieve the Guarantee Trustee from liability for its own
negligent action, its own negligent failure to act, or its own willful
misconduct, except that: 


     (i) prior to the occurrence of any
Event of Default and after the curing or waiving of all such Events of Default
that may have occurred: 


     (A) the duties and obligations of
the Guarantee Trustee shall be determined solely by the express provisions of
this Guarantee, and the Guarantee Trustee shall not be liable except for the
performance of such duties and obligations as are specifically set forth in this
Guarantee, and no implied covenants or obligations shall be read into this
Guarantee against the Guarantee Trustee; and 

     (B) in the absence of willful
misconduct or bad faith on the part of the Guarantee Trustee or any Responsible
Officer, the Guarantee Trustee may conclusively rely, as to the truth of the
statements and the correctness of the opinions expressed therein, upon any
certificates or opinions furnished to the Guarantee Trustee and conforming to
the requirements of this Guarantee; but in the case of any such certificates or
opinions that by any provision hereof are specifically required to be furnished
to the Guarantee Trustee, the Guarantee Trustee shall be under a duty to examine
the same to determine whether or not they conform to the requirements of this
Guarantee; 


     (ii) the Guarantee Trustee shall not
be liable for any error of judgment made in good faith by a Responsible Officer
of the Guarantee Trustee, unless it shall be proved that such Responsible
Officer of the Guarantee Trustee or the Guarantee Trustee was negligent in
ascertaining the pertinent facts upon which such judgment was made; 

     (iii) the Guarantee Trustee shall
not be liable with respect to any action taken or omitted to be taken by it in
good faith in accordance with the written direction of the Holders of not less
than a Majority in liquidation amount of the Capital Securities relating to the
time, method and place of conducting any proceeding for any remedy available to
the Guarantee Trustee, or relating to the exercise of any trust or power
conferred upon the Guarantee Trustee under this Guarantee; and 


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     (iv) no provision of this Guarantee
shall require the Guarantee Trustee to expend or risk its own funds or otherwise
incur personal financial liability in the performance of any of its duties or in
the exercise of any of its rights or powers, if the Guarantee Trustee shall have
reasonable grounds for believing that the repayment of such funds is not
reasonably assured to it under the terms of this Guarantee or security and
indemnity, reasonably satisfactory to the Guarantee Trustee, against such risk
or liability is not reasonably assured to it.


Section 2.2. Certain Rights of Guarantee Trustee. 

     (a) Subject to the provisions of
Section 2.1: 

          (i)
The Guarantee Trustee may conclusively rely, and shall be fully protected in
acting or refraining from acting upon, any resolution, certificate, statement,
instrument, opinion, report, notice, request, direction, consent, order, bond,
debenture, note, other evidence of indebtedness or other paper or document
believed by it to be genuine and to have been signed, sent or presented by the
proper party or parties. 

          (ii)
Any direction or act of the Guarantor contemplated by this Guarantee shall be
sufficiently evidenced by an Officer’s Certificate. 

          (iii)
Whenever, in the administration of this Guarantee, the Guarantee Trustee shall
deem it desirable that a matter be proved or established before taking,
suffering or omitting any action hereunder, the Guarantee Trustee (unless other
evidence is herein specifically prescribed) may, in the absence of bad faith on
its part, request and conclusively rely upon an Officer’s Certificate of the
Guarantor which, upon receipt of such request, shall be promptly delivered by
the Guarantor. 

          (iv)
The Guarantee Trustee shall have no duty to see to any recording, filing or
registration of any instrument (or any re-recording, refiling or re-registration
thereof). 

          (v)
The Guarantee Trustee may consult with counsel of its selection, and the advice
or opinion of such counsel with respect to legal matters shall be full and
complete authorization and protection in respect of any action taken, suffered
or omitted by it hereunder in good faith and in accordance with such advice or
opinion. Such counsel may be counsel to the Guarantor or any of its Affiliates
and may include any of its employees. The Guarantee Trustee shall have the right
at any time to seek instructions concerning the administration of this Guarantee
from any court of competent jurisdiction. 

          (vi)
The Guarantee Trustee shall be under no obligation to exercise any of the rights
or powers vested in it by this Guarantee at the request or direction of any
Holder, unless such Holder shall have provided to the Guarantee Trustee such
security and indemnity, reasonably satisfactory to the Guarantee Trustee,
against the costs, expenses (including attorneys’ fees and expenses and the
expenses of the Guarantee Trustee’s agents, nominees or custodians) and
liabilities that might be incurred by it in complying with such request or
direction, including such reasonable advances as may be requested by the
Guarantee Trustee; provided, however, that nothing contained in this Section
2.2(a)(vi) shall relieve the Guarantee Trustee, upon the occurrence of an Event
of Default, of its obligation to exercise the rights and powers vested in it by
this Guarantee. 

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          (vii)
The Guarantee Trustee shall not be bound to make any investigation into the
facts or matters stated in any resolution, certificate, statement, instrument,
opinion, report, notice, request, direction, consent, order, bond, debenture,
note, other evidence of indebtedness or other paper or document, but the
Guarantee Trustee, in its discretion, may make such further inquiry or
investigation into such facts or matters as it may see fit. 

          (viii)
The Guarantee Trustee may execute any of the trusts or powers hereunder or
perform any duties hereunder either directly or by or through agents, nominees,
custodians or attorneys, and the Guarantee Trustee shall not be responsible for
any misconduct or negligence on the part of any agent or attorney appointed with
due care by it hereunder. 

          (ix)
Any action taken by the Guarantee Trustee or its agents hereunder shall bind the
Holders of the Capital Securities, and the signature of the Guarantee Trustee or
its agents alone shall be sufficient and effective to perform any such action.
No third party shall be required to inquire as to the authority of the Guarantee
Trustee to so act or as to its compliance with any of the terms and provisions
of this Guarantee, both of which shall be conclusively evidenced by the
Guarantee Trustee’s or its agent’s taking such action. 

          (x)
Whenever in the administration of this Guarantee the Guarantee Trustee shall
deem it desirable to receive instructions with respect to enforcing any remedy
or right or taking any other action hereunder, the Guarantee Trustee (i) may
request instructions from the Holders of a Majority in liquidation amount of the
Capital Securities, (ii) may refrain from enforcing such remedy or right or
taking such other action until such instructions are received, and (iii) shall
be protected in conclusively relying on or acting in accordance with such
instructions. 

          (xi)
The Guarantee Trustee shall not be liable for any action taken, suffered, or
omitted to be taken by it in good faith, without negligence, and reasonably
believed by it to be authorized or within the discretion or rights or powers
conferred upon it by this Guarantee. 

     (b) No provision of this Guarantee
shall be deemed to impose any duty or obligation on the Guarantee Trustee to
perform any act or acts or exercise any right, power, duty or obligation
conferred or imposed on it, in any jurisdiction in which it shall be illegal or
in which the Guarantee Trustee shall be unqualified or incompetent in accordance
with applicable law to perform any such act or acts or to exercise any such
right, power, duty or obligation. No permissive power or authority available to
the Guarantee Trustee shall be construed to be a duty. 

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     Section 2.3.
Not Responsible for Recitals
or Issuance of Guarantee. The
recitals contained in this Guarantee shall be taken as the statements of the
Guarantor, and the Guarantee Trustee does not assume any responsibility for
their correctness. The Guarantee Trustee makes no representation as to the
validity or sufficiency of this Guarantee. 

     Section 2.4.
Events of Default;
Waiver. 

     (a) An Event of Default under this
Guarantee will occur upon the failure of the Guarantor to perform any of its
payment or other obligations hereunder. 

     (b) The Holders of a Majority in
liquidation amount of the Capital Securities may, voting or consenting as a
class, on behalf of the Holders of all of the Capital Securities, waive any past
Event of Default and its consequences. Upon such waiver, any such Event of
Default shall cease to exist, and shall be deemed to have been cured, for every
purpose of this Guarantee, but no such waiver shall extend to any subsequent or
other default or Event of Default or impair any right consequent thereon.


     Section 2.5.
Events of Default;
Notice. 

     (a) The Guarantee Trustee shall,
within 90 days after the occurrence of an Event of Default, transmit by mail,
first class postage prepaid, to the Holders of the Capital Securities and the
Guarantor, notices of all Events of Default actually known to a Responsible
Officer of the Guarantee Trustee, unless such defaults have been cured before
the giving of such notice, provided, however, that the Guarantee Trustee shall
be protected in withholding such notice if and so long as a Responsible Officer
of the Guarantee Trustee in good faith determines that the withholding of such
notice is in the interests of the Holders of the Capital Securities. 

     (b) The Guarantee Trustee shall not
be deemed to have knowledge of any Event of Default unless the Guarantee Trustee
shall have received written notice from the Guarantor or a Holder of the Capital
Securities (except in the case of a payment default), or any Responsible Officer
of the Guarantee Trustee charged with the administration of this Guarantee shall
have obtained actual knowledge thereof. 

ARTICLE III 

GUARANTEE TRUSTEE 

     Section 3.1.
Guarantee Trustee;
Eligibility. 

     (a) There shall at all times be a
Guarantee Trustee which shall: 


     (i) not be an Affiliate of the
Guarantor, and 

     (ii) be a corporation organized and
doing business under the laws of the United States of America or any State or
Territory thereof or of the District of Columbia, or Person authorized under
such laws to exercise corporate trust powers, having a combined capital and
surplus of at least 50 million U.S. dollars ($50,000,000), and subject to
supervision or examination by Federal, State, Territorial or District of
Columbia authority. If such corporation publishes reports of condition at least
annually, pursuant to law or to the requirements of the supervising or examining
authority referred to above, then, for the purposes of this Section 3.1(a)(ii),
the combined capital and surplus of such corporation shall be deemed to be its
combined capital and surplus as set forth in its most recent report of condition
so published. 


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     (b) If at any time the Guarantee
Trustee shall cease to be eligible to so act under Section 3.1(a), the Guarantee
Trustee shall immediately resign in the manner and with the effect set out in
Section 3.2(c).

     (c) If the Guarantee Trustee has or
shall acquire any “conflicting interest” within the meaning of Section 310(b) of
the Trust Indenture Act, the Guarantee Trustee shall either eliminate such
interest or resign to the extent and in the manner provided by, and subject to
this Guarantee. 

     Section 3.2.
Appointment, Removal and
Resignation of Guarantee Trustee.


     (a) Subject to Section 3.2(b), the
Guarantee Trustee may be appointed or removed without cause at any time by the
Guarantor except during an Event of Default. 

     (b) The Guarantee Trustee shall not
be removed in accordance with Section 3.2(a) until a Successor Guarantee Trustee
has been appointed and has accepted such appointment by written instrument
executed by such Successor Guarantee Trustee and delivered to the Guarantor.


     (c) The Guarantee Trustee appointed
to office shall hold office until a Successor Guarantee Trustee shall have been
appointed or until its removal or resignation. The Guarantee Trustee may resign
from office (without need for prior or subsequent accounting) by an instrument
in writing executed by the Guarantee Trustee and delivered to the Guarantor,
which resignation shall not take effect until a Successor Guarantee Trustee has
been appointed and has accepted such appointment by an instrument in writing
executed by such Successor Guarantee Trustee and delivered to the Guarantor and
the resigning Guarantee Trustee. 

     d) If no Successor Guarantee Trustee
shall have been appointed and accepted appointment as provided in this Section
3.2 within 60 days after delivery of an instrument of removal or resignation,
the Guarantee Trustee resigning or being removed may petition any court of
competent jurisdiction for appointment of a Successor Guarantee Trustee. Such
court may thereupon, after prescribing such notice, if any, as it may deem
proper, appoint a Successor Guarantee Trustee. 

     (e) No Guarantee Trustee shall be
liable for the acts or omissions to act of any Successor Guarantee Trustee.


     (f) Upon termination of this
Guarantee or removal or resignation of the Guarantee Trustee pursuant to this
Section 3.2, the Guarantor shall pay to the Guarantee Trustee all amounts owing
to the Guarantee Trustee under Sections 7.2 and 7.3 accrued to the date of such
termination, removal or resignation. 

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ARTICLE IV 

GUARANTEE

     Section 4.1.
Guarantee. 

     (a) The Guarantor irrevocably and
unconditionally agrees to pay in full to the Holders the Guarantee Payments
(without duplication of amounts theretofore paid by the Issuer), as and when
due, regardless of any defense (except the defense of payment by the Issuer),
right of set-off or counterclaim that the Issuer may have or assert. The
Guarantor’s obligation to make a Guarantee Payment may be satisfied by direct
payment of the required amounts by the Guarantor to the Holders or by causing
the Issuer to pay such amounts to the Holders. 

     (b) The Guarantor hereby also agrees
to assume any and all Obligations of the Issuer and in the event any such
Obligation is not so assumed, subject to the terms and conditions hereof, the
Guarantor hereby irrevocably and unconditionally guarantees to each Beneficiary
the full payment, when and as due, of any and all Obligations to such
Beneficiaries. This Guarantee is intended to be for the benefit of, and to be
enforceable by, all such Beneficiaries, whether or not such Beneficiaries have
received notice hereof. 

     Section 4.2.
Waiver of Notice and
Demand. The Guarantor hereby waives
notice of acceptance of this Guarantee and of any liability to which it applies
or may apply, presentment, demand for payment, any right to require a proceeding
first against the Issuer or any other Person before proceeding against the
Guarantor, protest, notice of nonpayment, notice of dishonor, notice of
redemption and all other notices and demands. 

     Section 4.3.
Obligations Not
Affected. The obligations,
covenants, agreements and duties of the Guarantor under this Guarantee shall in
no way be affected or impaired by reason of the happening from time to time of
any of the following: 

     (a) the release or waiver, by
operation of law or otherwise, of the performance or observance by the Issuer of
any express or implied agreement, covenant, term or condition relating to the
Capital Securities to be performed or observed by the Issuer; 

     (b) the extension of time for the
payment by the Issuer of all or any portion of the Distributions, Redemption
Price, Liquidation Distribution or any other sums payable under the terms of the
Capital Securities or the extension of time for the performance of any other
obligation under, arising out of or in connection with, the Capital Securities
(other than an extension of time for payment of Distributions, Redemption Price,
Liquidation Distribution or other sum payable that results from the extension of
any interest payment period on the Debentures or any extension of the maturity
date of the Debentures permitted by the Indenture); 

     (c) any failure, omission, delay or
lack of diligence on the part of the Holders to enforce, assert or exercise any
right, privilege, power or remedy conferred on the Holders pursuant to the terms
of the Capital Securities, or any action on the part of the Issuer granting
indulgence or extension of any kind; 

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     (d) the voluntary or involuntary
liquidation, dissolution, sale of any collateral, receivership, insolvency,
bankruptcy, assignment for the benefit of creditors, reorganization,
arrangement, composition or readjustment of debt of, or other similar
proceedings affecting, the Issuer or any of the assets of the Issuer;


     (e) any invalidity of, or defect or
deficiency in, the Capital Securities; 

     (f) the settlement or compromise of
any obligation guaranteed hereby or hereby incurred; or 

     (g) any other circumstance
whatsoever that might otherwise constitute a legal or equitable discharge or
defense of a guarantor, it being the intent of this Section 4.3 that the
obligations of the Guarantor hereunder shall be absolute and unconditional under
any and all circumstances. 

     There shall be no obligation of the
Holders to give notice to, or obtain consent of, the Guarantor with respect to
the happening of any of the foregoing. 

     Section 4.4.
Rights of
Holders. 

     (a) The Holders of a Majority in
liquidation amount of the Capital Securities have the right to direct the time,
method and place of conducting any proceeding for any remedy available to the
Guarantee Trustee in respect of this Guarantee or to direct the exercise of any
trust or power conferred upon the Guarantee Trustee under this Guarantee;
provided, however, that (subject to Section 2.1) the Guarantee Trustee shall
have the right to decline to follow any such direction if the Guarantee Trustee
being advised by counsel determines that the action or proceeding so directed
may not lawfully be taken or if the Guarantee Trustee in good faith by its board
of directors or trustees, executive committees or a trust committee of directors
or trustees and/or Responsible Officers shall determine that the action or
proceedings so directed would involve the Guarantee Trustee in personal
liability. 

     (b) Any Holder of Capital Securities
may institute a legal proceeding directly against the Guarantor to enforce the
Guarantee Trustee’s rights under this Guarantee, without first instituting a
legal proceeding against the Issuer, the Guarantee Trustee or any other Person.
The Guarantor waives any right or remedy to require that any such action be
brought first against the Issuer, the Guarantee Trustee or any other Person
before so proceeding directly against the Guarantor. 

     Section 4.5.
Guarantee of
Payment. This Guarantee creates a
guarantee of payment and not of collection. 

     Section 4.6.
Subrogation. The
Guarantor shall be subrogated to all (if any) rights of the Holders of Capital
Securities against the Issuer in respect of any amounts paid to such Holders by
the Guarantor under this Guarantee; provided, however, that the Guarantor shall
not (except to the extent required by mandatory provisions of law) be entitled
to enforce or exercise any right that it may acquire by way of subrogation or
any indemnity, reimbursement or other agreement, in all cases as a result of
payment under this Guarantee, if, after giving effect to any such payment, any
amounts are due and unpaid under this Guarantee. If any amount shall be paid to
the Guarantor in violation of the preceding sentence, the Guarantor agrees to
hold such amount in trust for the Holders and to pay over such amount to the
Holders. 

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     Section 4.7.
Independent
Obligations. The Guarantor
acknowledges that its obligations hereunder are independent of the obligations
of the Issuer with respect to the Capital Securities and that the Guarantor
shall be liable as principal and as debtor hereunder to make Guarantee Payments
pursuant to the terms of this Guarantee notwithstanding the occurrence of any
event referred to in subsections (a) through (g), inclusive, of Section 4.3
hereof. 

     Section 4.8.
Enforcement by a
Beneficiary. A Beneficiary may
enforce the obligations of the Guarantor contained in Section 4.1(b) directly
against the Guarantor and the Guarantor waives any right or remedy to require
that any action be brought against the Issuer or any other person or entity
before proceeding against the Guarantor. The Guarantor shall be subrogated to
all rights (if any) of any Beneficiary against the Issuer in respect of any
amounts paid to the Beneficiaries by the Guarantor under this Guarantee;
provided, however, that the Guarantor shall not (except to the extent required
by mandatory provisions of law) be entitled to enforce or exercise any rights
that it may acquire by way of subrogation or any indemnity, reimbursement or
other agreement, in all cases as a result of payment under this Guarantee, if at
the time of any such payment, and after giving effect to such payment, any
amounts are due and unpaid under this Guarantee. 

ARTICLE V 

LIMITATION OF TRANSACTIONS;
SUBORDINATION 

     Section 5.1.
Limitation of
Transactions. So long as any Capital
Securities remain outstanding, if (a) there shall have occurred and be
continuing an Event of Default or a Declaration Event of Default or (b) the
Guarantor shall have selected an Extension Period as provided in the Declaration
and such period, or any extension thereof, shall have commenced and be
continuing, then the Guarantor shall not and shall not permit any Affiliate to
(x) declare or pay any dividends or distributions on, or redeem, purchase,
acquire, or make a liquidation payment with respect to, any of the Guarantor’s
or such Affiliate’s capital stock (other than payments of dividends or
distributions to the Guarantor or payments of dividends from direct or indirect
subsidiaries of the Guarantor to their parent corporations, which also shall be
direct or indirect subsidiaries of the Guarantor) or make any guarantee payments
with respect to the foregoing or (y) make any payment of principal of or
interest or premium, if any, on or repay, repurchase or redeem any debt
securities of the Guarantor or any Affiliate that rank pari passu in all
respects with or junior in interest to the Debentures (other than, with respect
to clauses (x) and (y) above, (i) repurchases, redemptions or other acquisitions
of shares of capital stock of the Guarantor in connection with any employment
contract, benefit plan or other similar arrangement with or for the benefit of
one or more employees, officers, directors or consultants, in connection with a
dividend reinvestment or stockholder stock purchase plan or in connection with
the issuance of capital stock of the Guarantor (or securities convertible into
or exercisable for such capital stock) as consideration in an acquisition
transaction entered into prior to the occurrence of the Event of Default,
Declaration Event of Default or Extension Period, as applicable, (ii) as a
result of any exchange or conversion of any class or series of the Guarantor’s
capital stock (or any capital stock of a subsidiary of the Guarantor) for any
class or series of the Guarantor’s capital stock or of any class or series of
the Guarantor’s indebtedness for any class or series of the Guarantor’s capital
stock, (iii) the purchase of fractional interests in shares of the Guarantor’s
capital stock pursuant to the conversion or exchange provisions of such capital
stock or the security being converted or exchanged, (iv) any declaration of a
dividend in connection with any stockholders’ rights plan, or the issuance of
rights, stock or other property under any stockholders’ rights plan, or the
redemption or repurchase of rights pursuant thereto, (v) any dividend in the
form of stock, warrants, options or other rights where the dividend stock or the
stock issuable upon exercise of such warrants, options or other rights is the
same stock as that on which the dividend is being paid or ranks pari passu with
or junior to such stock and any cash payments in lieu of fractional shares
issued in connection therewith, or (vi) payments under this Guarantee).


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     Section 5.2.
Ranking. This
Guarantee will constitute an unsecured obligation of the Guarantor and will rank
subordinate and junior in right of payment to all present and future Senior
Indebtedness (as defined in the Indenture) of the Guarantor. By their acceptance
thereof, each Holder of Capital Securities agrees to the foregoing provisions of
this Guarantee and the other terms set forth herein.

     The right of the Guarantor to
participate in any distribution of assets of any of its subsidiaries upon any
such subsidiary’s liquidation or reorganization or otherwise is subject to the
prior claims of creditors of that subsidiary, except to the extent the Guarantor
may itself be recognized as a creditor of that subsidiary. Accordingly, the
Guarantor’s obligations under this Guarantee will be effectively subordinated to
all existing and future liabilities of the Guarantor’s subsidiaries, and
claimants should look only to the assets of the Guarantor for payments
hereunder. This Guarantee does not limit the incurrence or issuance of other
secured or unsecured debt of the Guarantor, including Senior Indebtedness of the
Guarantor, under any indenture that the Guarantor may enter into in the future
or otherwise. 

ARTICLE VI 

TERMINATION 

     Section 6.1.
Termination. This
Guarantee shall terminate as to the Capital Securities (i) upon full payment of
the Redemption Price of all Capital Securities then outstanding, (ii) upon the
distribution of all of the Debentures to the Holders of all of the Capital
Securities or (iii) upon full payment of the amounts payable in accordance with
the Declaration upon dissolution of the Issuer. This Guarantee will continue to
be effective or will be reinstated, as the case may be, if at any time any
Holder of Capital Securities must restore payment of any sums paid under the
Capital Securities or under this Guarantee. 

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ARTICLE VII

INDEMNIFICATION 

     Section 7.1.
Exculpation.

     (a) No Indemnified Person shall be
liable, responsible or accountable in damages or otherwise to the Guarantor or
any Covered Person for any loss, damage or claim incurred by reason of any act
or omission performed or omitted by such Indemnified Person in good faith in
accordance with this Guarantee and in a manner that such Indemnified Person
reasonably believed to be within the scope of the authority conferred on such
Indemnified Person by this Guarantee or by law, except that an Indemnified
Person shall be liable for any such loss, damage or claim incurred by reason of
such Indemnified Person’s negligence or willful misconduct with respect to such
acts or omissions. 

     (b) An Indemnified Person shall be
fully protected in relying in good faith upon the records of the Issuer or the
Guarantor and upon such information, opinions, reports or statements presented
to the Issuer or the Guarantor by any Person as to matters the Indemnified
Person reasonably believes are within such other Person’s professional or expert
competence and who, if selected by such Indemnified Person, has been selected
with reasonable care by such Indemnified Person, including information,
opinions, reports or statements as to the value and amount of the assets,
liabilities, profits, losses, or any other facts pertinent to the existence and
amount of assets from which Distributions to Holders of Capital Securities might
properly be paid. 

     Section 7.2.
Indemnification. 

     (a) The Guarantor agrees to
indemnify each Indemnified Person for, and to hold each Indemnified Person
harmless against, any and all loss, liability, damage, claim or expense incurred
without negligence or willful misconduct on the part of the Indemnified Person,
arising out of or in connection with the acceptance or administration of the
trust or trusts hereunder, including, but not limited to, the costs and expenses
(including reasonable legal fees and expenses) of the Indemnified Person
defending itself against, or investigating, any claim or liability in connection
with the exercise or performance of any of the Indemnified Person’s powers or
duties hereunder. The obligation to indemnify as set forth in this Section 7.2
shall survive the resignation or removal of the Guarantee Trustee and the
termination of this Guarantee. 

     (b) Promptly after receipt by an
Indemnified Person under this Section 7.2 of notice of the commencement of any
action, such Indemnified Person will, if a claim in respect thereof is to be
made against the Guarantor under this Section 7.2, notify the Guarantor in
writing of the commencement thereof; but the failure so to notify the Guarantor
(i) will not relieve the Guarantor from liability under paragraph (a) above
unless and to the extent that the Guarantor did not otherwise learn of such
action and such failure results in the forfeiture by the Guarantor of
substantial rights and defenses and (ii) will not, in any event, relieve the
Guarantor from any obligations to any Indemnified Person other than the
indemnification obligation provided in paragraph (a) above. 

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The Guarantor shall be entitled to
appoint counsel of the Guarantor’s choice at the Guarantor’s expense to
represent the Indemnified Person in any action for which indemnification is
sought (in which case the Guarantor shall not thereafter be responsible for the
fees and expenses of any separate counsel retained by the Indemnified Person or
Persons except as set forth below); provided, however, that such counsel shall
be reasonably satisfactory to the Indemnified Person. Notwithstanding the
Guarantor’s election to appoint counsel to represent the Guarantor in an action,
the Indemnified Person shall have the right to employ separate counsel
(including local counsel), and the Guarantor shall bear the reasonable fees,
costs and expenses of such separate counsel if (i) the use of counsel chosen by
the Guarantor to represent the Indemnified Person would present such counsel
with a conflict of interest, (ii) the actual or potential defendants in, or
targets of, any such action include both the Indemnified Person and the
Guarantor and the Indemnified Person shall have reasonably concluded that there
may be legal defenses available to it and/or other Indemnified Person(s) which
are different from or additional to those available to the Guarantor, (iii) the
Guarantor shall not have employed counsel satisfactory to the Indemnified Person
to represent the Indemnified Person within a reasonable time after notice of the
institution of such action or (iv) the Guarantor shall authorize the Indemnified
Person to employ separate counsel at the expense of the Guarantor. The Guarantor
will not, without the prior written consent of the Indemnified Persons, settle
or compromise or consent to the entry of any judgment with respect to any
pending or threatened claim, action, suit or proceeding in respect of which
indemnification or contribution may be sought hereunder (whether or not the
Indemnified Persons are actual or potential parties to such claim or action)
unless such settlement, compromise or consent includes an unconditional release
of each Indemnified Person from all liability arising out of such claim, action,
suit or proceeding. 

     Section 7.3.
Compensation; Reimbursement
of Expenses. The Guarantor agrees:


     (a) to pay to the Guarantee Trustee
from time to time such compensation for all services rendered by it hereunder as
the parties shall agree to from time to time (which compensation shall not be
limited by any provision of law in regard to the compensation of a trustee of an
express trust); and 

     (b) except as otherwise expressly
provided herein, to reimburse the Guarantee Trustee upon request for all
reasonable expenses, disbursements and advances incurred or made by it in
accordance with any provision of this Guarantee (including the reasonable
compensation and the expenses and disbursements of its agents and counsel),
except any such expense, disbursement or advance as may be attributable to its
negligence, bad faith or willful misconduct. 

     For purposes of clarification, this
Section 7.3 does not contemplate the payment by the Guarantor of acceptance or
annual administration fees owing to the Guarantee Trustee for services to be
provided by the Guarantee Trustee under this Guarantee or the fees and expenses
of the Guarantee Trustee’s counsel in connection with the closing of the
transactions contemplated by this Guarantee. The provisions of this Section 7.3
shall survive the resignation or removal of the Guarantee Trustee and the
termination of this Guarantee. 

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ARTICLE VIII

MISCELLANEOUS 

     Section 8.1.
Successors and
Assigns. All guarantees and
agreements contained in this Guarantee shall bind the successors, assigns,
receivers, trustees and representatives of the Guarantor and shall inure to the
benefit of the Holders of the Capital Securities then outstanding. Except in
connection with any merger, consolidation, reorganization, acquisition or
transfer of the Guarantor with or into another entity or any sale, transfer or
lease of the Guarantor’s assets to another entity, in each case, to the extent
permitted under the Indenture, the Guarantor may not assign its rights or
delegate its obligations under this Guarantee without the prior approval of the
Holders of at least a Majority in liquidation amount of the Capital Securities.


     Section 8.2.
Amendments. Except
with respect to any changes that do not adversely affect the powers,
preferences, rights or interests of Holders of the Capital Securities in any
material respect (in which case no consent of Holders will be required), this
Guarantee may be amended only with the prior approval of the Holders of not less
than a Majority in liquidation amount of the Capital Securities. The provisions
of the Declaration with respect to amendments thereof apply to the giving of
such approval. 

     Section 8.3.
Notices. All notices
provided for in this Guarantee shall be in writing, duly signed by the party
giving such notice, and shall be delivered, telecopied or mailed by first class
mail, as follows: 

     (a) If given to the Guarantee
Trustee, at the Guarantee Trustee’s mailing address set forth below (or such
other address as the Guarantee Trustee may give notice of to the Holders of the
Capital Securities and the Guarantor): 

Wilmington Trust Company
Rodney
Square North
1100 North Market Street
Wilmington, Delaware
19890-1600
Attention: Corporate Trust Administration
Telecopy:
302-636-4140 

     (b) If given to the Guarantor, at
the Guarantor’s mailing address set forth below (or such other address as the
Guarantor may give notice of to the Holders of the Capital Securities and to the
Guarantee Trustee): 

Enterprise Financial Services
Corp
1281 N. Warson Road St. Louis
Missouri 63132
Attention: Deborah N.
Barstow
Telecopy: 314-812-1506 

     (c) If given to any Holder of the
Capital Securities, at the address set forth on the books and records of the
Issuer. 

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     All such notices shall be deemed to
have been given when received in person, telecopied with receipt confirmed, or
mailed by first class mail, postage prepaid, except that if a notice or other
document is refused delivery or cannot be delivered because of a changed address
of which no notice was given, such notice or other document shall be deemed to
have been delivered on the date of such refusal or inability to deliver.


     Section 8.4.
Benefit. This
Guarantee is solely for the benefit of the Beneficiaries and, subject to Section
2.1(a), is not separately transferable from the Capital Securities. 

     Section 8.5.
Governing
Law. THIS GUARANTEE SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN
ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK, WITHOUT REGARD TO CONFLICT OF
LAWS PRINCIPLES THEREOF (OTHER THAN SECTION 5-1401 OF THE NEW YORK GENERAL
OBLIGATIONS LAW). 

     Section 8.6.
Counterparts. This
Guarantee may be executed in one or more counterparts, each of which shall be an
original, but all of which taken together shall constitute one and the same
instrument. 

     Section 8.7.
Separability. In case
one or more of the provisions contained in this Guarantee shall for any reason
be held to be invalid, illegal or unenforceable in any respect, such invalidity,
illegality or unenforceability shall not affect any other provisions of this
Guarantee, but this Guarantee shall be construed as if such invalid or illegal
or unenforceable provision had never been contained herein. 

Signatures appear on the following
page 

17






     THIS
GUARANTEE is executed as of the day and year first above written. 


	
      ENTERPRISE FINANCIAL SERVICES CORP.
      






	 
 
	By:  	 
	Its:  	 





	
      WILMINGTON TRUST COMPANY, as the
      Institutional Trustee 






	 
	By:  	 
	Its:  	 




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