EXHIBIT 4.7
                                                                     -----------

                        CAPITAL SECURITY CERTIFICATE


          THIS CAPITAL SECURITY IS A GLOBAL CAPITAL SECURITY WITHIN THE MEANING
OF THE TRUST AGREEMENT HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF
THE DEPOSITORY TRUST COMPANY (THE "CLEARING AGENCY") OR A NOMINEE OF THE
CLEARING AGENCY. THIS CAPITAL SECURITY IS EXCHANGEABLE FOR CAPITAL SECURITIES
REGISTERED IN THE NAME OF A PERSON OTHER THAN THE CLEARING AGENCY OR ITS NOMINEE
ONLY IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE TRUST AGREEMENT AND NO
TRANSFER OF THIS CAPITAL SECURITY (OTHER THAN A TRANSFER OF THIS CAPITAL
SECURITY AS A WHOLE BY THE CLEARING AGENCY TO A NOMINEE OF THE CLEARING AGENCY
OR BY A NOMINEE OF THE CLEARING AGENCY TO THE CLEARING AGENCY OR ANOTHER NOMINEE
OF THE CLEARING AGENCY) MAY BE REGISTERED EXCEPT IN LIMITED CIRCUMSTANCES.

          UNLESS THIS CAPITAL SECURITY IS PRESENTED BY AN AUTHORIZED
REPRESENTATIVE OF THE CLEARING AGENCY TO THE TRUST OR ITS AGENT FOR REGISTRATION
OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CAPITAL SECURITY ISSUED IS REGISTERED
IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE CLEARING AGENCY AND ANY PAYMENT HEREON IS MADE TO CEDE &
CO., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO
ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN
INTEREST HEREIN.

          THIS CAPITAL SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS OR ANY
OTHER APPLICABLE SECURITIES LAW. NEITHER THIS CAPITAL 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, REGISTRATION.

          THE HOLDER OF THIS CAPITAL SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO
OFFER, SELL OR OTHERWISE TRANSFER THIS CAPITAL SECURITY, PRIOR TO THE DATE (THE
"RESALE RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUANCE DATE HEREOF AND THE LAST DATE ON WHICH GREATER BAY BANCORP
(THE "CORPORATION") OR ANY "AFFILIATE" OF THE CORPORATION WAS THE OWNER OF THIS
CAPITAL SECURITY (OR ANY PREDECESSOR OF THIS CAPITAL SECURITY) ONLY (A) TO THE

 
CORPORATION, (B) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED
EFFECTIVE UNDER THE SECURITIES ACT, (C) SO LONG AS THIS CAPITAL SECURITY IS
ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE
144A"), TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER"
(AS DEFINED IN RULE 144A) THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT
OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS
BEING MADE IN RELIANCE ON RULE 144A, (D) TO AN INSTITUTIONAL "ACCREDITED
INVESTOR" WITHIN THE MEANING OF SUBPARAGRAPH (A)(1), (2), (3) OR (7) 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 (E) PURSUANT TO ANY
OTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS UNDER THE
SECURITIES ACT, SUBJECT TO THE RIGHT OF GBB CAPITAL II (THE "TRUST") AND THE
CORPORATION PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER (i) PURSUANT TO CLAUSE (D)
OR (E) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATIONS AND/OR
OTHER INFORMATION SATISFACTORY TO EACH OF THEM, AND (ii) PURSUANT TO CLAUSE (D)
TO REQUIRE THAT THE TRANSFEROR DELIVER TO THE TRUST A LETTER FROM THE TRANSFEREE
SUBSTANTIALLY IN THE FORM OF ANNEX A TO THE OFFERING MEMORANDUM DATED AUGUST 7,
1998. SUCH HOLDER FURTHER AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM
THIS CAPITAL SECURITY IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF
THIS LEGEND.

          THE HOLDER OF THIS CAPITAL 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 CAPITAL SECURITIES OR ANY INTEREST THEREIN,
UNLESS SUCH PURCHASER OR HOLDER IS ELIGIBLE FOR THE 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 CAPITAL SECURITIES 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 CAPITAL SECURITIES OR ANY INTEREST THEREIN WILL BE DEEMED TO
HAVE REPRESENTED BY ITS PURCHASE AND HOLDING THEREOF THAT EITHER (i) IT IS

                                       2

 
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.

     THE CAPITAL SECURITIES WILL BE ISSUED AND MAY BE TRANSFERRED ONLY IN BLOCKS
HAVING A LIQUIDATION AMOUNT OF NOT LESS THAN $100,000 (100 CAPITAL SECURITIES)
AND MULTIPLES OF $1,000 IN EXCESS THEREOF. ANY ATTEMPTED TRANSFER OF CAPITAL
SECURITIES IN A BLOCK HAVING A LIQUIDATION AMOUNT OF LESS THAN $100,000 (100
CAPITAL SECURITIES) SHALL BE DEEMED TO BE VOID AND OF NO LEGAL EFFECT
WHATSOEVER. ANY SUCH PURPORTED TRANSFEREE SHALL BE DEEMED NOT TO BE THE HOLDER
OF SUCH CAPITAL SECURITIES FOR ANY PURPOSE, INCLUDING, BUT NOT LIMITED TO, THE
RECEIPT OF DISTRIBUTIONS ON SUCH CAPITAL SECURITIES, AND SUCH PURPORTED
TRANSFEREE SHALL BE DEEMED TO HAVE NO INTEREST WHATSOEVER IN SUCH CAPITAL
SECURITIES.

     THE HOLDER OF THIS CAPITAL SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO BE
BOUND BY THE REGISTRATION RIGHTS AGREEMENT DATED AS OF AUGUST 7, 1998, BY AND
AMONG THE TRUST, THE SPONSOR AND THE INITIAL PURCHASER NAMED THEREIN, AS AMENDED
FROM TIME TO TIME.

                                       3

 
Certificate Number:  S-001                              Aggregate Liquidation
                                                        Amount:  $26,500,000

CUSIP Number:  361470 AA5

                  Certificate Evidencing Capital Securities

                                     of

                               GBB CAPITAL II

                 Floating Rate Capital Securities, Series A
              (liquidation amount $1,000 per Capital Security)

          GBB Capital II, a statutory business trust created under the laws of
the State of Delaware (the "Trust"), hereby certifies that Cede & Co. (the
"Holder") is the registered owner of Twenty-Six Million Five Hundred Thousand
Dollars ($26,500,000) in aggregate liquidation amount of Capital Securities of
the Trust representing undivided preferred beneficial interests in the assets of
the Trust designated the Floating Rate Capital Securities, Series A (liquidation
amount $1,000 per Capital Security) (the "Capital Securities"). 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 and shall in all respects be subject to
the provisions of the Amended and Restated Trust Agreement of the Trust, dated
as of August 12, 1998, as the same may be amended from time to time (the "Trust
Agreement"), including the designation of the terms of the Capital Securities as
set forth in Annex I to the Trust Agreement. Capitalized terms used but not
defined herein shall have the meaning given them in the Trust Agreement. The
Sponsor will provide a copy of the Trust Agreement, the Capital Securities
Guarantee and the Indenture (including any supplemental indenture) to a Holder
without charge upon written request to the Trust at its principal place of
business.

          Upon receipt of this Certificate, the Holder is bound by the Trust
Agreement and is entitled to the benefits thereunder and to the benefits of the
Capital Securities Guarantee to the extent provided therein.

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

                                       4

 
          IN WITNESS WHEREOF, the Trust has executed this certificate this 12th
day of August, 1998.

                              GBB CAPITAL II



                              By: /s/ Steven C. Smith
                                 ---------------------------------
                                 Steven C. Smith
                                 Administrative Trustee



              PROPERTY TRUSTEE'S CERTIFICATE OF AUTHENTICATION

     This is one of the Floating Rate Capital Securities, Series A of GBB
CAPITAL II referred to in the within-mentioned Trust Agreement.

Dated:    August 12, 1998


                              WILMINGTON TRUST COMPANY,
                              not in its individual capacity but solely
                              as Property Trustee

                              By:/s/ Patricia A. Evans
                                 ---------------------------------
                                  Authorized Signatory

                                       5

 
          Distributions on each Capital Security will be payable at a rate per
annum, reset quarterly, equal to 3-month LIBOR (as defined in the Trust
Agreement) plus 150 basis points (the "Coupon Rate"), such rate being the rate
of interest payable on the Debentures to be held by the Property Trustee.
Distributions in arrears for more than one quarterly period will bear interest
thereon compounded quarterly at the Coupon Rate (to the extent permitted by
applicable law). Pursuant to the Registration Rights Agreement, in certain
limited circumstances the Debenture Issuer will be required to pay Liquidated
Damages (as defined in the Registration Rights Agreement) with respect to the
Debentures. The term "Distributions," as used herein, includes such cash
distributions and any and all such interest and Liquidated Damages, if any,
payable unless otherwise stated. A Distribution is payable only to the extent
that payments are made in respect of the Debentures held by the Property Trustee
and to the extent the Property Trustee has funds legally available therefor.

          Distributions on the Capital Securities will be cumulative, will
accumulate from the most recent date to which Distributions have been paid or,
if no Distributions have been paid, from August 12, 1998 and will be payable
quarterly in arrears, on March 15, June 15, September 15 and December 15 of each
year, commencing December 15, 1998, except as otherwise described below.
Distributions will be computed on the basis of the actual number of days elapsed
in such period and a 360-day year. As long as no Event of Default has occurred
and is continuing under the Indenture, the Debenture Issuer has the right under
the Indenture to defer payments of interest by extending the interest payment
period at any time and from time to time on the Debentures for a period not
exceeding 20 consecutive calendar quarterly periods, including the first such
quarterly period during such extension period (each an "Extension Period"),
provided that no Extension Period shall end on a date other than an Interest
- -------- ----                                                               
Payment Date for the Debentures or extend beyond the Maturity Date of the
Debentures. As a consequence of such deferral, Distributions (other than
Liquidated Damages, if any) will also be deferred. Notwithstanding such
deferral, quarterly Distributions will continue to accumulate with interest
thereon (to the extent permitted by applicable law, but not at a rate exceeding
the rate of interest then accruing on the Debentures) at the applicable periodic
Coupon Rate compounded quarterly during any such Extension Period. Prior to the
termination of any Extension Period, the Debenture Issuer may further defer
payments of interest by further extending such Extension Period; provided that
                                                                 -------- ----
such Extension Period, together with all such previous and further extensions
within such Extension Period, may not (i) exceed 20 consecutive quarterly
periods, including the first quarterly period during such Extension Period, (ii)
end on a date other than an Interest Payment Date for the Debentures or (iii)
extend beyond the Maturity Date of the Debentures. Payments of accumulated
Distributions will be payable to Holders as they appear on the books and records
of the Trust on the record date immediately preceding the end of the Extension
Period. Upon the termination of any Extension Period and the payment of all
amounts then due, the Debenture Issuer may commence a new Extension Period,
subject to the above requirements.

          Subject to receipt by the Sponsor of any and all required regulatory
approvals and to certain other conditions set forth in the Trust Agreement and
the Indenture, the Property Trustee may, at the direction of the Sponsor, at any
time dissolve the Trust and after satisfaction of liabilities 

                                       6

 
to creditors of the Trust as provided by applicable law, cause the Debentures
to be distributed to the Holders of the Securities in liquidation of the Trust
or, simultaneously with any redemption of the Debentures, cause a Like Amount
of the Securities to be redeemed by the Trust.

          The Capital Securities shall be redeemable as provided in the Trust
Agreement.

                                       7

 
                       ________________________________

                                 ASSIGNMENT

                       ________________________________


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

________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
           (Assignee's social security or tax identification number)

________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
                       (Address and zip code of assignee)

and irrevocably appoints
________________________________________________________________________________
________________________________________________________________________________
__________________________________________________________________________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:_____________________________________



_________________________ 

     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 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 Registrar in addition to, or in substitution for, STAMP,
     all in accordance with the Securities Exchange Act of 1934, as amended.

                                       8

 
In connection with any transfer of any of the Capital Securities evidenced by
this Certificate, the undersigned confirms that such Capital Securities are
being:

CHECK ONE BOX BELOW

     (1)  [_]    exchanged for the undersigned's own account without transfer; 
                 or

     (2)  [_]    transferred pursuant to and in compliance with Rule 144A under
                 the Securities Act of 1933, as amended; or

     (3)  [_]     transferred to an institutional "accredited investor" within
                  the meaning of subparagraph (a)(1), (2), (3) or (7) of Rule
                  501 under the Securities Act of 1933 that is acquiring the
                  Capital Securities 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 of 1933, as amended; or      
 
     (4)  [_]     transferred pursuant to another available exemption from the
                  registration requirements of the Securities Act of 1933, as
                  amended; or

     (5)  [_]     transferred pursuant to an effective registration statement.

Unless one of the boxes is checked, the Registrar will refuse to register any of
the Capital Securities evidenced by this Certificate in the name of any Person
other than the Holder hereof; provided, however, that if box (3) or (4) is
                              --------  -------                           
checked, the Registrar may require, prior to registering any such transfer of
the Capital Securities, such legal opinions, certifications and other
information as the Trust has reasonably requested to confirm that such transfer
is being made pursuant to an exemption from, or in a transaction not subject to,
the registration requirements of the Securities Act of 1933, as amended, such as
the exemption provided by Rule 144 under such Act; provided, further, that (i)
                                                   --------  -------          
if box (2) is checked, by acceptance of this Certificate, the transferee shall
be deemed to have certified that it is a "qualified institutional buyer" (as
defined in Rule 144A) ("QIB") acquiring the Capital Securities for its own
account or for the account of another QIB over which it exercises sole
investment discretion and that it is aware that the Holder is relying upon the
exemption from registration afforded by Rule 144A in respect of the Holder's
transfer of Capital Securities to it or (ii) if box (3) is checked, the
transferee must also provide to the Registrar a Transferee Letter of
Representation in the form attached to the Offering Memorandum of the Trust
dated August 7, 1998; provided, further, that after the date that a registration
                      --------  -------                                         
statement has been filed and so long as such Registration Statement continues to
be effective, only then may the Registrar permit transfers for which box (5) has
been checked.



                                       _______________________________________
                                                  Signature

                                       9