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                                                                   EXHIBIT 10.55

                                     FORM OF
                          SAFETY INSURANCE GROUP, INC.
                     2002 MANAGEMENT OMNIBUS INCENTIVE PLAN

                        NOTICE OF RESTRICTED STOCK GRANT
                      FOR RESTRICTED STOCK WITH NO VESTING

     You (the "Grantee") have been granted the following shares of Restricted
Stock of Safety Insurance Group, Inc. (the "Company"), par value $0.01 per share
("Share"), pursuant to the Safety Insurance Group, Inc. 2002 Management Omnibus
Incentive Plan (the "Plan"):

<Table>
<S>                                             <C>
Name of Grantee:                                [               ]

Number of Shares of Restricted Stock Granted:   [        ]

Per Share Value of Common Stock at Grant:       [        ]

Date of Grant:                                  [        ]

Periods of Restriction:                         Subject to the terms of the Plan and the
                                                Restricted Stock Award Agreement attached
                                                hereto, the Period of Restriction with
                                                respect to the Restricted Stock shall
                                                lapse, and the Shares shall become free of
                                                the forfeiture and transfer restrictions
                                                contained in the Restricted Stock Award
                                                Agreement at the time the Grantee is no
                                                longer a member of the Board of Directors.
</Table>

By your signature and the signature of the Company's representative below, you
and the Company agree that the Restricted Stock evidenced hereby is granted
under and governed by the terms and conditions of the Plan and the Restricted
Stock Award Agreement, both of which are attached to and made a part of this
document.

   GRANTEE:                                   SAFETY INSURANCE GROUP, INC.:

                                              By:
   ----------------------------------            -------------------------------
   Date:                                      Title:
        -----------------------------               ----------------------------
   Address:                                   Date:
           --------------------------              -----------------------------

           --------------------------

           --------------------------

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                                     FORM OF
                          SAFETY INSURANCE GROUP, INC.
                        RESTRICTED STOCK AWARD AGREEMENT
                      FOR RESTRICTED STOCK WITH NO VESTING

SECTION 1. GRANT OF RESTRICTED STOCK

     (a)   RESTRICTED STOCK. On the terms and conditions set forth in the Notice
of Restricted Stock Grant and this Restricted Stock Agreement (the "Agreement"),
the Company grants to the Grantee on the Date of Grant the Restricted Stock set
forth in the Notice of Restricted Stock Grant. The Restricted Stock Award is
granted in respect of past services and services to be performed. It has been
determined that the value of the past services performed by the Grantee equals
or exceeds the par value of the Shares subject to this Agreement.

     (b)   PLAN AND DEFINED TERMS. The Restricted Stock is granted pursuant to
the Plan, a copy of which the Grantee acknowledges having received. All terms,
provisions, and conditions applicable to the Restricted Stock set forth in the
Plan and not set forth herein are hereby incorporated by reference herein. To
the extent any provision hereof is inconsistent with a provision of the Plan,
the provisions of the Plan will govern. All capitalized terms that are used in
the Notice of Restricted Stock Grant or this Agreement and not otherwise defined
therein or herein shall have the meanings ascribed to them in the Plan.

SECTION 2. FORFEITURE AND TRANSFER RESTRICTIONS

     (a)   FORFEITURE RESTRICTIONS. Article 9 of the Plan shall not be
applicable to the Restricted Stock granted pursuant to the Notice of Restricted
Stock Grant and this Agreement; provided, however, any attempt to transfer the
Restricted Stock in violation of Section 2(b) shall cause the Restricted Stock
granted hereunder to be forfeited.

     (b)   TRANSFER RESTRICTIONS. The Restricted Stock may not be sold,
assigned, pledged, exchanged, hypothecated or otherwise transferred, encumbered
or disposed of to the extent such Shares are subject to a Period of Restriction.

     (c)   LAPSE OF RESTRICTIONS. The Period of Restriction shall lapse as to
the Restricted Stock in accordance with the provisions of the Notice of
Restricted Stock Grant. Subject to the terms of the Plan and Section 4(a)
hereof, upon lapse of the Period of Restriction, the Grantee shall own the
Shares that are subject to this Agreement free of all restrictions otherwise
imposed by this Agreement.

SECTION 3. DIVIDENDS, VOTING RIGHTS AND CUSTODY

     The Grantee shall be entitled to vote and receive dividends on the Shares
subject to this Agreement; provided, however, that no dividends shall be payable
to the Grantee, and the Grantee will not be entitled to vote Shares of
Restricted Stock, with respect to record dates occurring prior to the Date of
Grant. The Shares subject to this Agreement shall be registered in the name of
the Grantee and held in custody by the Company.

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SECTION 4. MISCELLANEOUS PROVISIONS

     (a)   RATIFICATION OF ACTIONS. By accepting this Agreement, the Grantee and
each person claiming under or through the Grantee shall be conclusively deemed
to have indicated the Grantee's acceptance and ratification of, and consent to,
any action taken under the Plan or this Agreement and Notice of Restricted Stock
Grant by the Company, the Board, or the Committee.

     (b)   NOTICE. Any notice required by the terms of this Agreement shall be
given in writing and shall be deemed effective upon personal delivery or upon
deposit with the United States Postal Service, by registered or certified mail,
with postage and fees prepaid. Notice shall be addressed to the Company at its
principal executive office and to the Grantee at the address that he or she most
recently provided in writing to the Company.

     (c)   CHOICE OF LAW. This Agreement and the Notice of Restricted Stock
Grant shall be governed by, and construed in accordance with, the laws of New
York, as such laws are applied to contracts entered into and performed in such
state.

     (d)   COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

     (e)   MODIFICATION OR AMENDMENT. This Agreement may only be modified or
amended by written agreement executed by the parties hereto; provided, however,
that the adjustments permitted pursuant to Section 4.2 of the Plan may be made
without such written agreement.

     (f)   SEVERABILITY. In the event any provision of this Agreement shall be
held illegal or invalid for any reason, the illegality or invalidity shall not
affect the remaining provisions of this Agreement, and this Agreement shall be
construed and enforced as if such illegal or invalid provision had not been
included.

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