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                                                                  EXHIBIT 10.6

                                 FIFTH AMENDMENT
                                     TO THE
                 BROOKLINE SAVINGS BANK EMPLOYEE STOCK OWNERSHIP
                                      PLAN

         The Brookline Savings Bank Employee Stock Ownership Plan is hereby
         amended effective January 1, 2000, unless otherwise stated in
         accordance with the following:

         Section 2, Definitions, the definition of "Employer" is hereby amended
         as follows:

                  "Employer" means the Bank or any affiliate (within the purview
                  of section 414(b), (c) or (m) and 415(h) of the Code) which
                  adopts this Plan with the Bank's consent pursuant to Section
                  13.1 or any other corporation, Partnership, or proprietorship
                  which adopts this Plan with the Bank's consent pursuant to
                  section 13.1, and any entity which succeeds to the business of
                  the Employer and adopts the Plan pursuant to section 13.2.

         IN WITNESS THEREOF, this amendment has been adopted by the Bank as of
         the 21st of June, 2000 and executed by its duly authorized officers.

         ATTEST:                                    BROOKLINE SAVINGS BANK

         \s\ Charles H. Peck                        \s\ Richard P. Chapman, Jr.
         -------------------------------            ---------------------------
         Secretary                                  Executive Officer
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                                                                   EXHIBIT 10.6a

                                 LIGHTHOUSE BANK
                             STOCK OPTION AGREEMENT

         This Stock Option Agreement ("Option Agreement") entered into
effective as of this 3rd day of May, 2000, represents the understanding of
Thomas R. Venables ("Executive") and Lighthouse Bank (the "Bank") and
Brookline Bancorp, Inc. ("BBI"), with respect to options ("Options") to
acquire the common stock of the Bank in the amount and pursuant to the terms
described below.

                                    RECITALS:

         A. BBI has entered into an employment agreement ("Employment
Agreement") with Executive dated as of August 1, 1999, which Employment
Agreement has been assumed by the Bank;

         B. In partial consideration of Executive's entering into such
Employment Agreement, the Bank desires to grant Options to the Executive upon
the following terms and conditions:

         In consideration of their mutual covenants and other good and valued
consideration, the receipt of which is hereby acknowledged, the parties hereto
agree as follows:

         (1)      Executive is hereby granted Options to purchase four percent
                  (4%) of the common stock of the Bank (or 40,000 options),
                  which Options shall be treated as incentive stock options to
                  the extent permissible under federal law.

         (2)      The Options granted herein shall vest at the rate of forty
                  percent (40%) at the end of the first twelve months following
                  the date hereof (the "Anniversary Date") and thereafter shall
                  vest at the rate of twenty percent (20%) on each succeeding
                  Anniversary Date. Provided, however, that upon a Change in
                  Control (as defined in the Employment Agreement), each Option
                  granted hereunder shall automatically be deemed fully vested
                  for all purposes.

         (3)      In event the Bank issues any additional shares of common stock
                  in exchange for additional capital, the Executive shall be
                  granted additional Options equal to four percent (4%) of the
                  additional shares issued; provided, however, that new Options
                  shall not be granted with respect to any shares to be sold in
                  a public offering of the Bank's common stock for which a
                  registration statement is filed with the Securities and
                  Exchange Commission.

         (4)      The exercise price of each Option granted hereby shall be
                  Twenty-Five Dollars ($25.00), which is the per share price
                  paid by BBI at the time of initial capitalization of the Bank,
                  and is the fair market value of the shares on the date of
                  grant. The exercise price of any additional Options that may
                  be granted to Executive in connection with the issuance of
                  additional shares of common stock shall be the per share price
                  paid for the additional shares. It is contemplated that such
                  per share price shall be the same as the per share fair market
                  value of the additional shares on the date they are issued.

         (5)      In the event there is no public market for the common stock of
                  the Bank at the end of four (4) years from the date hereof,
                  Executive shall have the right to sell to BBI or, at the
                  election of BBI, to the Bank, shares of the Bank obtained
                  through the exercise of options which were exercised at least
                  six months prior to the date of sale. The maximum number of
                  shares that can be sold to BBI, or at the election of BBI, to
                  the Bank each year shall equal fifty percent (50%) of the
                  shares covered by the Options granted and the sales price per
                  share shall be the per share fair market value at the time of
                  sale. If no public market exists for the Bank's common stock,
                  at the request of Executive, which request shall not be made
                  more than once in any twelve (12) month period, or at the
                  election of BBI, BBI shall engage an independent appraisal
                  firm to determine the fair market value of the Bank's common
                  stock beginning at the end of the fourth year after formation
                  of the Bank. In the event of a sale to BBI in accordance with
                  this paragraph, BBI may elect to
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                  engage an independent appraisal firm to determine the fair
                  market value of the common stock of the Bank. If no new
                  appraisal is obtained, the fair market value of the Bank's
                  common stock shall be deemed to be the fair market value
                  determined at the last valuation.

         (6)      In the event of the occurrence of an Event of Termination (as
                  defined in the Employment Agreement), Executive shall have the
                  right to receive a cash payment equal to the difference
                  between the fair market value of the Executive's vested
                  Options and the exercise price of such Options. BBI shall
                  engage an independent appraisal firm to determine the fair
                  market value as of the Date of Termination (as defined in the
                  Employment Agreement).

ATTEST:                                         LIGHTHOUSE BANK

By: /s/ Linda Rosen                             By: /s/ Richard P. Chapman, Jr.
    -----------------------------                   ---------------------------
    Linda Rosen                                     Richard P. Chapman, Jr.

WITNESS:                                        EXECUTIVE

    /s/Thomas R. Venables                           /s/Claire S. Bean
    -----------------------------                   ---------------------------
    Thomas R. Venables                              Claire S. Bean

ATTEST:                                         BROOKLINE BANCORP, INC.

    /s/Linda Rosen                                  /s/Richard P. Chapman, Jr.
    -----------------------------                   ---------------------------
    Linda Rosen                                     Richard P. Chapman, Jr.<PAGE>
                                                                  EXHIBIT 10.6b

                                 LIGHTHOUSE BANK
                             STOCK OPTION AGREEMENT

         This Stock Option Agreement ("Option Agreement") entered into effective
as of this 3rd day of May, 2000, represents the understanding of Claire S. Bean
("Executive") and Lighthouse Bank (the "Bank") and Brookline Bancorp, Inc.
("BBI"), with respect to options ("Options") to acquire the common stock of the
Bank in the amount and pursuant to the terms described below.

                                    RECITALS:

         A. BBI has entered into an employment agreement ("Employment
Agreement") with Executive dated as of August 1, 1999, which Employment
Agreement has been assumed by the Bank;

         B. In partial consideration of Executive's entering into such
Employment Agreement, the Bank desires to grant Options to the Executive upon
the following terms and conditions:

         In consideration of their mutual covenants and other good and valued
consideration, the receipt of which is hereby acknowledged, the parties hereto
agree as follows:

         (1)      Executive is hereby granted Options to purchase four percent
                  (4%) of the common stock of the Bank (or 40,000 options),
                  which Options shall be treated as incentive stock options to
                  the extent permissible under federal law.

         (2)      The Options granted herein shall vest at the rate of forty
                  percent (40%) at the end of the first twelve months following
                  the date hereof (the "Anniversary Date") and thereafter shall
                  vest at the rate of twenty percent (20%) on each succeeding
                  Anniversary Date. Provided, however, that upon a Change in
                  Control (as defined in the Employment Agreement), each Option
                  granted hereunder shall automatically be deemed fully vested
                  for all purposes.

         (3)      In event the Bank issues any additional shares of common stock
                  in exchange for additional capital, the Executive shall be
                  granted additional Options equal to four percent (4%) of the
                  additional shares issued; provided, however, that new Options
                  shall not be granted with respect to any shares to be sold in
                  a public offering of the Bank's common stock for which a
                  registration statement is filed with the Securities and
                  Exchange Commission.

         (4)      The exercise price of each Option granted hereby shall be
                  Twenty-Five Dollars ($25.00), which is the per share price
                  paid by BBI at the time of initial capitalization of the Bank,
                  and is the fair market value of the shares on the date of
                  grant. The exercise price of any additional Options that may
                  be granted to Executive in connection with the issuance of
                  additional shares of common stock shall be the per share price
                  paid for the additional shares. It is contemplated that such
                  per share price shall be the same as the per share fair market
                  value of the additional shares on the date they are issued.

         (5)      In the event there is no public market for the common stock of
                  the Bank at the end of four (4) years from the date hereof,
                  Executive shall have the right to sell to BBI or, at the
                  election of BBI, to the Bank, shares of the Bank obtained
                  through the exercise of options which were exercised at least
                  six months prior to the date of sale. The maximum number of
                  shares that can be sold to BBI, or at the election of BBI, to
                  the Bank each year shall equal fifty percent (50%) of the
                  shares covered by the Options granted and the sales price per
                  share shall be the per share fair market value at the time of
                  sale. If no public market exists for the Bank's common stock,
                  at the request of Executive, which request shall not be made
                  more than once in any twelve (12) month period, or at the
                  election of BBI, BBI shall engage an independent appraisal
                  firm to determine the fair market value of the Bank's common
                  stock beginning at the end of the fourth year after formation

<PAGE>

                  of the Bank. In the event of a sale to BBI in accordance with
                  this paragraph, BBI may elect to engage an independent
                  appraisal firm to determine the fair market value of the
                  common stock of the Bank. If no new appraisal is obtained, the
                  fair market value of the Bank's common stock shall be deemed
                  to be the fair market value determined at the last valuation.

         (6)      In the event of the occurrence of an Event of Termination (as
                  defined in the Employment Agreement), Executive shall have the
                  right to receive a cash payment equal to the difference
                  between the fair market value of the Executive's vested
                  Options and the exercise price of such Options. BBI shall
                  engage an independent appraisal firm to determine the fair
                  market value as of the Date of Termination (as defined in the
                  Employment Agreement).

ATTEST:                                        LIGHTHOUSE BANK

By: /s/Linda Rosen                             By: /s/ Richard P. Chapman, Jr.
   --------------------------                     -----------------------------
   Linda Rosen                                    Richard P. Chapman, Jr.

WITNESS:                                       EXECUTIVE

/s/Thomas R. Venables                          /s/Claire S. Bean
-----------------------------                  ---------------------------------
Thomas R. Venables                             Claire S. Bean

ATTEST:                                        BROOKLINE BANCORP, INC.

/s/Linda Rosen                                 /s/Richard P. Chapman, Jr.
-----------------------------                  ---------------------------------
Linda Rosen                                    Richard P. Chapman, Jr.

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