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                                                                   EXHIBIT 10(g)

                                                  No. 2521-0031-E001

                                   ENDORSEMENT

Attached to and forming part of the PROPERTY PER RISK EXCESS OF LOSS REINSURANCE
AGREEMENT No. 2521-0031 between MERCHANTS MUTUAL INSURANCE COMPANY, Buffalo, New
York and MERCHANTS INSURANCE COMPANY OF NEW HAMPSHIRE, INC., Concord, New
Hampshire (hereinafter collectively referred to as "Company") and AMERICAN
RE-INSURANCE COMPANY, a Delaware Corporation with Administrative Offices in
Princeton, New Jersey (hereinafter referred to as the "Reinsurer").

It is mutually understood and agreed by the parties hereto that effective
January 1, 2003, as respects the Company's in-force, new and renewal policies,
as respects losses occurring on or after said date, this Agreement is amended to
read as follows:

I.       Paragraph B. of ARTICLE III, RETENTION AND LIMIT, is amended to reflect
         the addition of an annual aggregate limit for "NBCR" Terrorist Activity
         and the Paragraph reads as follows:

         B.       Notwithstanding the aforementioned, the following limits shall
                  apply as respects all loss, cost or expense arising from or
                  related to, either directly or indirectly, any Terrorist
                  Activity, as defined in the DEFINITIONS Article:

                  $3,000,000 Ultimate Net Loss each Loss Occurrence, and
                  $6,000,000 Ultimate Net Loss in the aggregate as respects all
                  such Loss Occurrences for each Agreement Year. However, the
                  Reinsurer's liability shall be limited to $3,000,000 in the
                  aggregate as respects all such Occurrences arising from loss
                  as defined in Paragraph G.,3.,c, of the DEFINITIONS Article
                  for each Agreement Year.

II.      Exclusion B., 22., of ARTICLE V, EXCLUSIONS, is amended to include
Property Target Classes and the Exclusion reads in its entirety as follows:

         22.      A.       Any loss, cost or expense arising out of or related
                           to, either directly or indirectly, any Terrorist
                           Activity, as defined in the DEFINITIONS Article, with
                           respect to Risks with a Total Insured Value at the
                           time of loss greater than or equal to $50,000,000 and
                           the following risks, classes of business, or accounts
                           applicable to Policies reinsured hereunder:

                           (1)      Airports and Aircraft

                           (2)      Apartments/Condos/Co-Ops > 25 stories

                           (3)      Automobile Mfrs.

                           (4)      Bridges

                           (5)      Casinos and Casino Hotels

                           (6)      Chemical Mfg. and Distribution Cos.

                           (7)      Convention/Exhibition Centers

Revised: September 24, 2003

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                                                     No. 2521-0031-E001

                           (8)      Cruise Lines

                           (9)      Dams

                           (10)     Defense/Aerospace Industries

                           (11)     Financial Institutions with more than 10
                                    branch locations

                           (12)     Government Buildings (Fed/State) and
                                    National Landmarks

                           (13)     High Tech Mfg. Cos.

                           (14)     Hospitals

                           (15)     Hotels > 25 stories

                           (16)     Internet Cos.

                           (17)     Major Media Cos.

                           (18)     Nuclear Facility exposures

                           (19)     Office Buildings > 25 stories

                           (20)     Petrochemical/Oil and Gas Cos.

                           (21)     Pipelines (oil and gas)

                           (22)     Port/Transit Authorities

                           (23)     Property Management Cos - High Rise exposure
                                    > 25 stories

                           (24)     Railroads

                           (25)     Enclosed Shopping Malls - property owner
                                    only

                           (26)     Stadiums

                           (27)     Tunnels

                           (28)     Universities

                           (29)     Utility Cos. - electric, gas, water and
                                    sewer

                  B.       This exclusion applies regardless of any other cause
                           or event that in any way contributes concurrently or
                           in any sequence to loss, cost, or expense.


III.     Paragraph G., Terrorist Activity, of ARTICLE VI, DEFINITIONS, is
amended to add the definition of "chemical" and the definition reads as follows:

         The term "chemical" as used herein shall mean any substance obtained by
         a chemical process or used for producing a chemical effect for the
         purposes of Terrorist Activity.

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                                                     No. 2521-0031-E001

IV.      ARTICLE XIII, REINSURANCE PREMIUM, is amended to reflect the change in
the Commercial Property Rate to xx.xx% and the Article reads in its entirety as
follows:

                                  ARTICLE XIII

         REINSURANCE PREMIUM

         With respect to business in force and business becoming effective at
         and after the effective time and date of this Agreement, the rates for
         the reinsurance provided hereunder shall be as follows:

         1.       x.xx% of the Company's unearned premium on Homeowners Multiple
                  Peril (Section I) after deducting that portion, if any, paid
                  for share reinsurance, calculated on the monthly pro rata
                  basis as of the effective time and date of this Agreement; and

         2.       xx.xx% of the Company's unearned premium on all other classes
                  of business reinsured hereunder (except Automobile Physical
                  Damage), after deducting that portion, if any, paid for share
                  reinsurance, calculated on the monthly pro rata basis as of
                  the effective time and date of this Agreement.

Nothing herein contained shall alter, vary or extend any provision or condition
of the Agreement other than as above stated.

IN WITNESS WHEREOF the parties hereto have caused this Endorsement to be
executed in duplicate this            day of                     ,2003;

ACCEPTED:
MERCHANTS MUTUAL INSURANCE COMPANY
MERCHANTS INSURANCE COMPANY OF NEW HAMPSHIRE, INC.

-----------------------
and in Princeton, New Jersey this             day of            , 2003.

                                                AMERICAN RE-INSURANCE COMPANY

                                                -----------------------
                                                Vice President

DATED: February 27, 2003

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