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                                                                     EXHIBIT 4.4

                          CAPITAL SECURITY CERTIFICATE

                               [FACE OF SECURITY]

        THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933,
AS AMENDED (THE "SECURITIES ACT"), ANY STATE SECURITIES LAWS OR ANY OTHER
APPLICABLE SECURITIES LAW. NEITHER THIS SECURITY NOR ANY INTEREST OR
PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED,
ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR
UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, THE REGISTRATION
REQUIREMENTS OF THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES LAWS. THE
HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO OFFER, SELL OR
OTHERWISE TRANSFER THIS SECURITY ONLY (A) TO THE SPONSOR OR THE TRUST, (B)
PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE
SECURITIES ACT, (C) TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A
QUALIFIED INSTITUTIONAL BUYER IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE
144A SO LONG AS THIS SECURITY IS ELIGIBLE FOR RESALE PURSUANT TO RULE 144A IN
ACCORDANCE WITH RULE 144A, (D) TO A NON-U.S. PERSON IN AN OFFSHORE TRANSACTION
IN ACCORDANCE WITH RULE 903 OR RULE 904 (AS APPLICABLE) OF REGULATION S UNDER
THE SECURITIES ACT, (E) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN THE
MEANING OF SUBPARAGRAPH (A) OF RULE 501 UNDER THE SECURITIES ACT THAT IS
ACQUIRING THIS CAPITAL SECURITY FOR ITS OWN ACCOUNT, OR FOR THE ACCOUNT OF SUCH
AN INSTITUTIONAL ACCREDITED INVESTOR, FOR INVESTMENT PURPOSES AND NOT WITH A
VIEW TO, OR FOR OFFER OR SALE IN CONNECTION WITH, ANY DISTRIBUTION IN VIOLATION
OF THE SECURITIES ACT, OR (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE SPONSOR'S AND
THE TRUST'S RIGHT PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER TO REQUIRE THE
DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION
SATISFACTORY TO EACH OF THEM IN ACCORDANCE WITH THE DECLARATION OF TRUST, A COPY
OF WHICH MAY BE OBTAINED FROM THE SPONSOR OR THE TRUST. HEDGING TRANSACTIONS
INVOLVING THIS SECURITY MAY NOT BE CONDUCTED UNLESS IN COMPLIANCE WITH THE
SECURITIES ACT.

        THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF ALSO AGREES,
REPRESENTS AND WARRANTS THAT IT IS NOT AN EMPLOYEE BENEFIT, INDIVIDUAL
RETIREMENT ACCOUNT OR OTHER PLAN OR ARRANGEMENT SUBJECT TO TITLE I OF THE
EMPLOYEE RETIREMENT INCOME SECURITY ACT OF 1974, AS AMENDED ("ERISA"), OR
SECTION 4975 OF THE INTERNAL REVENUE CODE OF 1986, AS AMENDED (THE "CODE") (EACH
A "PLAN"), OR AN ENTITY WHOSE UNDERLYING ASSETS INCLUDE "PLAN ASSETS" BY REASON
OF ANY PLAN'S INVESTMENT IN THE ENTITY, AND NO PERSON INVESTING "PLAN ASSETS" OF
ANY PLAN MAY ACQUIRE OR HOLD THE SECURITIES OR ANY

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INTEREST THEREIN, UNLESS SUCH PURCHASER OR HOLDER IS ELIGIBLE FOR EXEMPTIVE
RELIEF AVAILABLE UNDER U.S. DEPARTMENT OF LABOR PROHIBITED TRANSACTION CLASS
EXEMPTION 96-23, 95-60, 91-38, 90-1 OR 84-14 OR ANOTHER APPLICABLE EXEMPTION OR
ITS PURCHASE AND HOLDING OF THIS SECURITY IS NOT PROHIBITED BY SECTION 406 OF
ERISA OR SECTION 4975 OF THE CODE WITH RESPECT TO SUCH PURCHASE OR HOLDING. ANY
PURCHASER OR HOLDER OF THE SECURITIES OR ANY INTEREST THEREIN WILL BE DEEMED TO
HAVE REPRESENTED BY ITS PURCHASE AND HOLDING THEREOF THAT EITHER (i) IT IS NOT
AN EMPLOYEE BENEFIT PLAN WITHIN THE MEANING OF SECTION 3(3) OF ERISA, OR A PLAN
TO WHICH SECTION 4975 OF THE CODE IS APPLICABLE, A TRUSTEE OR OTHER PERSON
ACTING ON BEHALF OF AN EMPLOYEE BENEFIT PLAN OR PLAN, OR ANY OTHER PERSON OR
ENTITY, USING THE ASSETS OF ANY EMPLOYEE BENEFIT PLAN OR PLAN TO FINANCE SUCH
PURCHASE, OR (ii) SUCH PURCHASE WILL NOT RESULT IN A PROHIBITED TRANSACTION
UNDER SECTION 406 OF ERISA OR SECTION 4975 OF THE CODE FOR WHICH THERE IS NO
APPLICABLE STATUTORY OR ADMINISTRATIVE EXEMPTION.

         THIS SECURITY WILL BE ISSUED AND MAY BE TRANSFERRED ONLY IN BLOCKS
HAVING A LIQUIDATION AMOUNT OF NOT LESS THAN $500,000.00 (500 SECURITIES) AND
MULTIPLES OF $1,000.00 IN EXCESS THEREOF. ANY ATTEMPTED TRANSFER OF SECURITIES
IN A BLOCK HAVING A LIQUIDATION AMOUNT OF LESS THAN $500,000.00 SHALL BE DEEMED
TO BE VOID AND OF NO LEGAL EFFECT WHATSOEVER.

         THE HOLDER OF THIS SECURITY AGREES THAT IT WILL COMPLY WITH THE
FOREGOING RESTRICTIONS.

         IN CONNECTION WITH ANY TRANSFER, THE HOLDER WILL DELIVER TO THE
REGISTRAR AND TRANSFER AGENT SUCH CERTIFICATES AND OTHER INFORMATION AS MAY BE
REQUIRED BY THE DECLARATION TO CONFIRM THAT THE TRANSFER COMPLIES WITH THE
FOREGOING RESTRICTIONS.

          Certificate Number 1          Number of Capital Securities 10,000

                                November 19, 2002

             Certificate Evidencing Floating Rate Capital Securities

                                       of

                   Texas Capital Bancshares Statutory Trust I

               (liquidation amount $1,000.00 per Capital Security)

           Texas Capital Bancshares Statutory Trust I, a statutory trust created
under the laws of the State of Connecticut (the "Trust"), hereby certifies that
STI Investment Management, Inc.

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  (the "Holder") is the registered owner of securities of the Trust
  representing undivided beneficial interests in the assets of the Trust,
  (liquidation amount $1,000.00 per capital security) (the "Capital
  Securities"). Subject to the Declaration (as defined below), the
  Capital Securities are transferable on the books and records of the
  Trust in person or by a duly authorized attorney, upon surrender of
  this Certificate duly endorsed and in proper form for transfer. The
  designation, rights, privileges, restrictions, preferences and other
  terms and provisions of the Capital Securities represented hereby are
  issued pursuant to, and shall in all respects be subject to, the
  provisions of the Amended and Restated Declaration of Trust of the
  Trust dated as of November 19, 2002, among Joseph M. Grant, Raleigh
  Hortenstine III and Gregory B. Hultgren as Administrators, State Street
  Bank and Trust Company of Connecticut, National Association, as
  Institutional Trustee, Texas Capital Bancshares, Inc., as Sponsor, and
  the holders from time to time of undivided beneficial interests in the
  assets of the Trust, including the designation of the terms of the
  Capital Securities as set forth in Annex I to such amended and restated
  declaration as the same may be amended from time to time (the
  "Declaration"). Capitalized terms used herein but not defined shall
  have the meaning given them in the Declaration. The Holder is entitled
  to the benefits of the Guarantee to the extent provided therein. The
  Sponsor will provide a copy of the Declaration, the Guarantee, and the
  Indenture to the Holder without charge upon written request to the
  Trust at its principal place of business.

        Upon receipt of this Security, the Holder is bound by the Declaration
and is entitled to the benefits thereunder.

        By acceptance of this Security, the Holder agrees to treat, for United
States federal income tax purposes, the Debentures as indebtedness and the
Capital Securities as evidence of beneficial ownership in the Debentures.

        This Capital Security is governed by, and construed in accordance with,
the laws of the State of Connecticut, without regard to principles of conflict
of laws.

         IN WITNESS WHEREOF, the Trust has duly executed this certificate.

                                            TEXAS CAPITAL BANCSHARES
                                            STATUTORY TRUST I



                                            By:     /s/ RALEIGH HORTENSTINE III
                                                --------------------------------
                                                 Name:  Raleigh Hortenstine III
                                                 Title: Administrator

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                          CERTIFICATE OF AUTHENTICATION

         This is one of the Capital Securities referred to in the within
mentioned Declaration.


                                          STATE STREET BANK AND TRUST COMPANY
                                          OF CONNECTICUT, NATIONAL ASSOCIATION,
                                          as the Institutional Trustee


                                          By:    /s/ EARL W. DENNISON, JR.
                                             -----------------------------------
                                                     Authorized Officer


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                              [REVERSE OF SECURITY]

        Distributions payable on each Capital Security will be payable at an
annual rate equal to 4.77% beginning on (and including) the date of original
issuance and ending on (but excluding) December 31, 2002 and at an annual rate
for each successive period beginning on (and including) December 31, 2002, and
each succeeding Distribution Payment Date, and ending on (but excluding) the
next succeeding Distribution Payment Date (each a "Distribution Period"), equal
to 3-Month LIBOR, determined as described below, plus 3.35% (the "Coupon Rate"),
applied to the stated liquidation amount of $1,000.00 per Capital Security, such
rate being the rate of interest payable on the Debentures to be held by the
Institutional Trustee.

        In the event that the 3-Month LIBOR is indeterminable by the methods
described below, the Coupon Rate shall equal the 3-Month LIBOR in effect on the
most recent Determination Date (whether or not 3-Month LIBOR for such period was
in fact determined on such Determination Date) plus 3.35%.

        Distributions in arrears for more than a quarterly period will bear
interest thereon compounded quarterly at the Distribution Rate (to the extent
permitted by applicable law). The term "Distributions" as used herein includes
payments of Interest and any principal on the Debentures held by the
Institutional Trustee unless otherwise stated. A Distribution is payable only to
the extent that payments are made in respect of the Debentures held by the
Institutional Trustee and to the extent the Institutional Trustee has funds
available therefor. In the event that any date on which a Distribution is
payable on this Capital Security is not a Business Day, then a payment of the
Distribution payable on such date will be made on the next succeeding day which
is a Business Day (and without any Distribution or other payment in respect of
any such delay), with the same force and effect as if made on the date the
payment was originally payable. The amount of interest payable for any
Distribution Period will be calculated by applying the Coupon Rate to the
principal amount outstanding at the commencement of the Distribution Period and
multiplying each such amount by the actual number of days in the Distribution
Period concerned divided by 360.

        "3-Month LIBOR" means the London interbank offered rate for three-month,
U.S. dollar deposits determined by the Debenture Trustee in the following order
of priority; provided, however, that prior to November 19, 2007, the 3-Month
LIBOR shall not exceed 8.50%:

                (1) the rate (expressed as a percentage per annum) for U.S.
         dollar deposits of an amount equal or comparable to the aggregate
         liquidation amount of the Debentures having a three-month maturity that
         appears on Telerate Page 3750 as of 11:00 a.m. (London time) on the
         particular Determination Date (as defined below). "Telerate Page 3750"
         means the display designated as "Page 3750" on the Dow Jones Telerate
         Service or such other page as may replace Page 3750 on that service or
         such other service or services as may be nominated by the British
         Bankers' Association as the information vendor for the purpose of
         displaying London interbank offered rates for U.S. dollars deposits;

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                (2) if such rate does not appear on Telerate Page 3750 as of
         11:00 a.m. (London time) on the Determination Date, 3-Month LIBOR will
         be the arithmetic mean of the rates (expressed as percentages per
         annum) for U.S. dollar deposits of an amount equal or comparable to the
         aggregate liquidation amount of the Debentures having a three-month
         maturity that appear on Reuters Monitor Money Rates Page LIBO ("Reuters
         Page LIBO") as of 11:00 a.m. (London time) on such Determination Date;

                (3) if such rate does not appear on Reuters Page LIBO as of
         11:00 a.m. (London time) on the related Determination Date, the
         Debenture Trustee will request the principal London offices of four
         leading banks in the London interbank market to provide such banks'
         offered quotations (expressed as percentages per annum) to prime banks
         in the London interbank market for U.S. dollar deposits of an amount
         equal or comparable to the aggregate liquidation amount of the
         Debentures having a three-month maturity as of 11:00 a.m. (London time)
         on such Determination Date. If at least two quotations are provided,
         3-Month LIBOR will be the arithmetic mean of such quotations; and

                (4) if fewer than two such quotations are provided as requested
         in clause (3) above, the Debenture Trustee will request four major New
         York City banks to provide such banks' offered quotations (expressed as
         percentages per annum) to leading European banks for loans in U.S.
         dollars of an amount equal or comparable to the aggregate liquidation
         amount of the Debentures as of 11:00 a.m. (London time) on such
         Determination Date. If at least two such quotations are provided,
         3-Month LIBOR will be the arithmetic mean of such quotations.

         If the rate for U.S. dollar deposits of an amount equal or comparable
to the aggregate liquidation amount of the Debentures having a three-month
maturity that initially appears on Telerate Page 3750 or Reuters Page LIBO, as
the case may be, as of 11:00 a.m. (London time) on the related Determination
Date is superseded on the Telerate page 3750 or Reuters Page LIBO, as the case
may be, by a corrected rate by 12:00 noon (London time) on such Determination
Date, then the corrected rate as so substituted on the applicable page will be
the applicable 3-Month LIBOR for such Determination Date.

                (5) The Coupon Rate for any Distribution Period will at no time
         be higher than the maximum rate then permitted by New York law as the
         same may be modified by United States law.

         "Determination Date" means the date that is two London Banking Days
(i.e., a day in which dealings in deposits in U.S. dollars are transacted in the
London interbank market) preceding the commencement of the relevant Distribution
Period.

         All percentages resulting from any calculations on the Capital
Securities will be rounded, if necessary, to the nearest one hundred-thousandth
of a percentage point, with five one-millionths of a percentage point rounded
upward (e.g., 9.876545% or .09876545 being rounded to 9.87655% or .0987655), and
all dollar amounts used in or resulting from such calculation will be rounded to
the nearest cent (with one-half cent being rounded upward).

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         Except as otherwise described below, Distributions on the Capital
Securities will be cumulative, will accrue from the date of original issuance
and will be payable quarterly in arrears on March 31, June 30, September 30 and
December 31 of each year, commencing on December 31. 2002. The Debenture Issuer
has the right under the Indenture to defer payments of interest on the
Debentures by extending the interest payment period for up to 20 consecutive
quarterly periods (each an "Extension Period") on the Debentures, subject to the
conditions described below, although such interest would continue to accrue on
the Debentures at an annual rate equal to the Distribution Rate compounded
quarterly to the extent permitted by law during any Extension Period. No
Extension Period may end on a date other than a Distribution Payment Date. At
the end of any such Extension Period the Debenture Issuer shall pay all interest
then accrued and unpaid on the Debentures (together with Additional Interest
thereon); provided, however, that no Extension Period may extend beyond the
Maturity Date. Prior to the termination of any Extension Period, the Debenture
Issuer may further extend such period, provided that such period together with
all such previous and further consecutive extensions thereof shall not exceed 20
consecutive quarterly periods, or extend beyond the Maturity Date. Upon the
termination of any Extension Period and upon the payment of all accrued and
unpaid interest and Additional Interest, the Debenture Issuer may commence a new
Extension Period, subject to the foregoing requirements. No interest or
Additional Interest shall be due and payable during an Extension Period, except
at the end thereof, but each installment of interest that would otherwise have
been due and payable during such Extension Period shall bear Additional
Interest. If Distributions are deferred, the Distributions due shall be paid on
the date that the related Extension Period terminates, to Holders of the
Securities as they appear on the books and records of the Trust on the record
date immediately preceding such date. Distributions on the Securities must be
paid on the dates payable (after giving effect to any Extension Period) to the
extent that the Trust has funds available for the payment of such distributions
in the Property Account of the Trust. The Trust's funds available for
Distribution to the Holders of the Securities will be limited to payments
received from the Debenture Issuer. The payment of Distributions out of moneys
held by the Trust is guaranteed by the Guarantor pursuant to the Guarantee.

         The Capital Securities shall be redeemable as provided in the
Declaration.


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                                   ASSIGNMENT

FOR VALUE RECEIVED, the undersigned assigns and transfers this Capital Security
Certificate to:

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(Insert assignee's social security or tax identification number)

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(Insert address and zip code of assignee) and irrevocably appoints


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         agent to transfer this Capital Security Certificate on the books of the
Trust. The agent may substitute another to act for him or her.

         Date:
               -----------------------------

         Signature:
                    ------------------------

         (Sign exactly as your name appears on the other side of this Capital
Security Certificate)

         Signature Guarantee:(1)


--------
(1) Signature must be guaranteed by an "eligible guarantor institution" that is
a bank, stockbroker, savings and loan association or credit union meeting the
requirements of the Security registrar, which requirements include membership or
participation in the Securities Transfer Agents Medallion Program ("STAMP") or
such other "signature guarantee program" as may be determined by the Security
registrar in addition to, or in substitution for, STAMP, all in accordance with
the Securities Exchange Act of 1934, as amended.

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