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                                                                   Exhibit 10 BB

                        MERCANTILE BANKSHARES CORPORATION
                                OPTION AGREEMENT

         This Option Agreement is entered into this 7th day of May, 2002, by and
between Mercantile Bankshares Corporation ("MBC"), a Maryland corporation, and
J. Marshall Reid ("Grantee").

                                    ARTICLE 1
                                   DEFINITIONS

         For purposes of this Agreement, the definitions set forth in Sections
1.1 through 1.18 shall be applicable.

         Section 1.1 Affiliate.  "Affiliate" shall mean: (i) any corporation in
which MBC owns, directly or indirectly, within the meaning of (S)424(f) of the
Code, fifty percent (50%) or more of the total combined voting power of all
classes of stock of such corporation on a Grant Date; and (ii) any parent
corporation of MBC, within the meaning of (S)424(e) of the Code.

         Section 1.2 Agreement. "Agreement" shall mean this Option Agreement and
shall include the Plan, which is hereby incorporated into and made a part of the
Agreement.

         Section 1.3 Anniversary Date. "Anniversary Date" shall mean March 12 of
each of the first three years after the Grant Date.

         Section 1.4 Board. "Board" shall mean the Board of Directors of MBC.

         Section 1.5 Code. "Code" shall mean the Internal Revenue Code of 1986,
as amended, and any regulations issued thereunder.

         Section 1.6 Committee. "Committee" shall mean the Committee appointed
pursuant to Section 3.3 of the Plan.

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         Section 1.7 Disability. "Disability" shall mean Grantee's inability to
engage in any substantial gainful activity, by reason of any medically
determined physical or mental impairment that may be expected to result in death
or that has lasted or may be expected to last for a continuous period of not
less than twelve (12) months, as determined by the Committee based on proof of
the existence of such disability in such form and manner and at such times as
the Committee may require.

         Section 1.8 Exercise Date. "Exercise Date" shall mean the date on which
the Committee receives the written notice required under Section 3.2 of this
Agreement that Grantee has exercised the Option.

         Section 1.9 Fair Market Value. "Fair Market Value" of a share of Stock
on the Grant Date or Exercise Date, as the case may be, shall be calculated in
accordance with the Plan, in good faith in accordance with the Code.

         Section 1.10 Grant Date. "Grant Date" shall mean March 12, 2002.

         Section 1.11 Incentive Stock Option. "Incentive Stock Option" shall
mean an option as defined in (S)422(b) of the Code.

         Section 1.12 Normal Retirement Date. "Normal Retirement Date" shall
mean the first day of the month coincident with or next following the date on
which Grantee attains age sixty-five (65).

         Section 1.13 Option. "Option" shall mean an option to acquire Stock
and, to the fullest extent permitted by the Code and other applicable law, shall
mean an Incentive Stock Option.

         Section 1.14 Option Amount. "Option Amount" shall mean 15,000 shares of
Stock.

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         Section 1.15 Option Price. "Option Price" shall mean the price per
share of Stock at which the Option may be exercised.

         Section 1.16 Plan. "Plan" shall mean the Mercantile Bankshares
Corporation 1999 Omnibus Stock Plan.

         Section 1.17 Retirement. "Retirement" shall mean early or normal
retirement in accordance with the terms of The Cash Balance Plan for Employees
of Mercantile Bankshares Corporation and Participating Affiliates, as it may
exist from time to time, or any successor plan.

         Section 1.18 Stock. "Stock" shall mean shares of MBC's authorized but
unissued common stock.

                                    ARTICLE 2

                                 GRANT OF OPTION

         Section 2.1 Grant of Option. On the Grant Date, MBC, pursuant to the
Plan, granted to Grantee an Option to purchase shares of Stock, not to exceed
the Option Amount, at an Option Price of $44.99 per share. To the fullest extent
permitted by the Code and other applicable law, the Option shall be an Incentive
Stock Option.

         Section 2.2 Term of Option. The Option granted pursuant to Section 2.1
shall expire on March 11, 2012, unless and to the extent that the Option
terminates earlier pursuant to other provisions of this Agreement.

                                    ARTICLE 3

                               EXERCISE OF OPTION

         Section 3.1 Exercisability of Option. The Option shall become
exercisable in three equal or substantially equal annual installments (with such
adjustments as MBC shall deem appropriate to avoid fractional share amounts)
commencing on the first

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Anniversary Date, unless and to the extent the Option has earlier terminated
pursuant to the provisions of this Agreement.

         Section 3.2 Manner of Exercise. The Option may be exercised, in whole
or in part, by delivering written notice to the Committee in such form as the
Committee may require from time to time. Such notice shall specify the number of
shares of Stock subject to the Option as to which the Option is being exercised,
and shall be accompanied by full payment of the Option Price of the shares of
Stock as to which the Option is being exercised. Payment of the Option Price may
be made either in cash or shares of Stock (including shares of Stock acquired
upon the exercise of an option) having a total Fair Market Value on the Exercise
Date equal to the Option Price multiplied by the number of shares of Stock as to
which the Option is being exercised. The Option may be exercised only in
multiples of whole shares and no partial shares shall be issued. The minimum
number of shares of Stock for which the Option may be exercised shall be the
lesser of one hundred (100) shares or the entire number of shares for which the
Option is exercisable on the Exercise Date. If, as of the third Anniversary
Date, the total number of shares as to which the Option is exercisable includes
a partial share, the Option for such partial share, whether or not previously
designated by the Committee as an Incentive Stock Option, shall be deemed to be
a non-Incentive Stock Option. On the first date, on or after the third
Anniversary Date, that the Fair Market Value of a share of Stock equals or
exceeds the Option Price, Grantee shall be deemed to have simultaneously
exercised the Option for such partial share and to have sold same to MBC for
such Fair Market Value. MBC shall remit to Grantee, in payment of the purchase
price for such partial share, the excess, if any, of the Fair Market Value of
such partial share over the Option Price.

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         Section 3.3 Issuance of Shares and Payment of Cash upon Exercise. Upon
exercise of the Option, in whole or in part, in accordance with the terms of
this Agreement, and upon payment of the Option Price for the shares of Stock as
to which the Option is exercised, MBC shall issue to Grantee the number of
shares of Stock so paid for, in the form of fully paid and non-assessable Stock.

         Section 3.4 Loan or Guaranty. Solely at the discretion of the
Committee, and upon Grantee's written request, MBC may, but shall not be
required to, assist Grantee in the exercise of the Option by making a loan to
Grantee or by guaranteeing a third-party loan to Grantee. Such a loan or
guaranty shall be conditioned upon prior receipt by the Committee of
satisfactory assurances of Grantee's net worth and repayment ability. Subject to
Regulation U of the Federal Reserve Board, any such loan or guaranty may be in
an amount up to one hundred percent (100%) of the Option Price of the shares of
Stock as to which the Option is being exercised. All loans shall bear interest
at a rate determined by the Committee based upon loans of similar maturity, but
in no event shall the interest rate be less than the rate necessary to avoid the
imputation of interest or original issue discount under the provisions of the
Code. All other terms of any loan or guaranty (including terms of repayment)
shall be established by the Committee, subject to Regulation U of the Federal
Reserve Board and all other applicable federal and state laws and regulations.

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                                    ARTICLE 4

                            TERMINATION OF EMPLOYMENT

         Section 4.1 Termination of Employment For Reason Other Than Death,
Disability or Retirement. The Option granted to Grantee shall terminate with
respect to any shares of Stock as to which the Option has not been exercised as
of the date Grantee is no longer employed by either MBC or an Affiliate for any
reason other than Grantee's death, disability or retirement, whether or not the
Option was exercisable on such date.

         Section 4.2 Upon Grantee's Death. In the event that upon Grantee's date
of death any portion of the Option is exercisable, then Grantee's executor,
personal representative or the person to whom the Option shall have been
transferred by will or the laws of descent and distribution, as the case may be,
may exercise all or any part of the portion of the Option exercisable as of the
date of death, provided such exercise occurs within twelve (12) months after the
date Grantee dies, but not later than the end of the stated term of the Option.
Upon Grantee's death, the portion of the Option, if any, that has not become
exercisable as of the date of Grantee's death shall terminate on the date of
Grantee's death.

         Section 4.3 Termination of Employment By Reason of Disability. In the
event that Grantee ceases to be an employee of MBC or an Affiliate by reason of
Disability, the portion of the Option, if any, that has become exercisable as of
the date of Disability may be exercised in whole or in part at any time on or
after the date of Disability, but not later than the end of the stated term of
the Option or as otherwise provided by the

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provisions of Section 4.2 of this Agreement. Upon Grantee's termination of
employment by reason of Disability, the portion of the Option, if any, that has
not become exercisable as of the date of Disability shall terminate on the date
of Disability.

         Section 4.4  Termination of Employment By Reason of Retirement.

                  (a) Early Retirement.

                      (i)   Exercisable Portion of Option. In the event that
Grantee ceases to be an employee of MBC or an Affiliate by reason of Retirement
at any time prior to Grantee's Normal Retirement Date, the portion of the
Option, if any, that has become exercisable as of the date of Retirement may be
exercised in whole or in part at any time on or after the date of Retirement,
but not later than the end of the stated term of the Option or as otherwise
provided by the provisions of Section 4.2 of this Agreement.

                      (ii)  Non-exercisable Portion of Option. In the event that
Grantee ceases to be an employee of MBC or an Affiliate by reason of Retirement
at any time prior to Grantee's Normal Retirement Date, the portion of the
Option, if any, that has not become exercisable as of the date of Retirement
shall terminate on the date of Retirement.

                  (b) Normal Retirement.

                      (i)   Exercisable Portion of Option. In the event that
Grantee ceases to be an employee of MBC or an Affiliate by reason of Retirement
on or after Grantee's Normal Retirement Date, the portion of the Option, if any,
that has become exercisable as of the date of Retirement may be exercised in
whole or in part at any time on or after the date of Retirement, but not later
than the end of the stated term of the

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Option or as otherwise provided by the provisions of Section 4.2 of this
Agreement.

                      (ii)  Non-exercisable Portion of Option. In the event that
upon the occurrence of Grantee's Retirement on or after Grantee's Normal
Retirement Date all or a portion of the Option has not become exercisable solely
because one (1) or more of the first three (3) Anniversary Dates have not
occurred (hereinafter referred to as the "Remaining Portion"), then such
Remaining Portion shall become exercisable upon the date of Retirement. In all
cases, the Remaining Portion shall not include any portion of the Option that
has terminated pursuant to other provisions of this Agreement. The Remaining
Portion of the Option that becomes exercisable on such Retirement date may be
exercised in whole or in part at any time thereafter, but not later than the end
of the stated term of the Option or as otherwise provided by the provisions of
Section 4.2 of this Agreement.

                                    ARTICLE 5

                                  MISCELLANEOUS

         Section 5.1 Non-Guarantee of Employment. Nothing in the Plan or this
Agreement shall be construed as a contract of employment between MBC (or an
Affiliate) and Grantee, or as a contractual right of Grantee to continue in the
employ of MBC or an Affiliate, or as a limitation of the right of MBC or an
Affiliate to discharge Grantee at any time.

         Section 5.2 No Rights of Stockholder. Grantee shall not have any of the
rights of a stockholder with respect to the shares of Stock that may be issued
upon the exercise of the Option until such shares of Stock have been issued to
him upon the due exercise of the Option.

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         Section 5.3 Notice of Disqualifying Disposition. If Grantee makes a
disposition (as that term is defined in (S)424(c) of the Code) of any shares of
Stock acquired pursuant to the exercise of an Incentive Stock Option within two
(2) years of the Grant Date or within one (1) year after the shares of Stock are
transferred to Grantee, Grantee shall notify the Committee of such disposition
in writing.

         Section 5.4 Withholding Taxes. MBC or any Affiliate shall have the
right to deduct from any compensation or any other payment of any kind
(including withholding the issuance of shares of Stock) due Grantee the amount
of any federal, state or local taxes required by law to be withheld as the
result of the exercise of the Option or the disposition (as that term is defined
in (S)424(c) of the Code) of shares of Stock acquired pursuant to the exercise
of the Option. In lieu of such deduction, MBC may require Grantee to make a cash
payment to MBC or an Affiliate equal to the amount required to be withheld. If
Grantee does not make such payment when requested, MBC may refuse to issue any
Stock certificate under the Plan until arrangements satisfactory to the
Committee for such payment have been made.

         Section 5.5 Nontransferability of Option. Except as otherwise
determined by the Committee, the Option shall be nontransferable otherwise than
by will or the laws of descent and distribution, and during the lifetime of
Grantee, the Option may be exercised only by Grantee or, during the period
Grantee is under a legal disability, by Grantee's guardian or legal
representative.

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         Section 5.6 Agreement Subject to Charter and By-Laws. This Agreement is
subject to the Charter and By-Laws of MBC, and any applicable federal or state
laws, rules or regulations.

         Section 5.7 Gender. As used herein the masculine shall include the
feminine as the circumstances may require.

         Section 5.8 Headings. The headings in this Agreement are for reference
purposes only and shall not affect the meaning or interpretation of the
Agreement.

         Section 5.9 Notices. All notices and other communications made or given
pursuant to this Agreement shall be in writing and shall be sufficiently made or
given if hand delivered or mailed by certified mail, addressed to Grantee at the
address contained in the records of MBC or an Affiliate, or to MBC for the
attention of its Secretary at its principal office.

                                    ARTICLE 6

                               SCOPE OF AGREEMENT

         Section 6.1 Entire Agreement; Modification. This Agreement contains the
entire agreement between the parties with respect to the subject matter
contained herein and shall be binding upon MBC, its successors and assigns and
upon Grantee and Grantee's heirs, personal representatives and assigns. This
Agreement may be modified by the Committee as permitted by the Plan, including
modification under Section 9.3 thereof and any modification to comply with the
Code or to cure any ambiguity or to correct or supplement any provision which
may be inconsistent with any other provision or which may be otherwise
defective.

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         Section 6.2 Counterparts. This Agreement may be executed simultaneously
in one or more counterparts, each of which shall be deemed to be an original and
all of which together shall constitute one and the same instrument. Signatures
evidencing execution of this Agreement on behalf of the Corporation may be in
facsimile or photocopy form.

         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.

ATTEST:                            MERCANTILE BANKSHARES CORPORATION

 /s/ Alan D. Yarbro                By: /s/ Edward J. Kelley, III
----------------------------          ------------------------------------------
Alan D. Yarbro                             Edward J. Kelly, III
Secretary                                  President and Chief Executive Officer



WITNESS:                           GRANTEE


 /s/ Deborah Stamper                 /s/ J. Marshall Reid
----------------------------       ---------------------------------------------
                                   Signature

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