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Exhibit 10.45

        [Swiss Re Logo]

ADDENDUM NO. 3

to the

CASUALTY EXCESS OF LOSS
REINSURANCE AGREEMENT
NO. POR327454
(hereinafter referred to as the "Agreement")

between

SAFETY INSURANCE COMPANY
SAFETY INDEMNITY INSURANCE COMPANY
both of Boston, Massachusetts
(hereinafter collectively referred to as the "Company")

and

SWISS REINSURANCE AMERICA CORPORATION
Armonk, New York
(hereinafter and thereinafter referred to as the "Reinsurer")

I.It is understood and agreed that effective as of inception Article
III—Territory, is amended as follows:

ARTICLE III—TERRITORY

This Agreement applies to Policies issued by the Company within the United
States of America, its territories and possessions, and Canada and shall apply
tb losses covered hereunder wherever
occurring.

II.It is also understood and agreed that as respects policies in force at
12:01 a.m., Eastern Standard Time, September 1, 2007, and new and renewal
policies becoming effective on and after said date, Safety Property and Casualty
Company is added as a party to this Agreement and in consideration thereof the
respective section of the Preamble is revised to read:

SAFETY INSURANCE COMPANY
SAFETY INDEMNITY INSURANCE COMPANY
SAFETY PROPERTY AND CASUALTY INSURANCE COMPANY
all of Boston, Massachusetts
(hereinafter collectively referred to as the "Company")

ALL OTHER TERMS AND CONDITIONS REMAIN UNCHANGED.

1. No. POR327454
    Addendum No. 3

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IN WITNESS WHEREOF, the parties hereto have caused this Addendum to be executed
in duplicate, by their duly authorized representatives as of the following
dates:

In Boston, Massachusetts, this 12 day of DEC, 2007.

ATTEST:   SAFETY INSURANCE COMPANY
SAFETY INDEMNITY INSURANCE COMPANY
SAFETY PROPERTY AND CASUALTY INSURANCE
COMPANY
/s/ Glenn Hiltpold, FCAS

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/s/ Edward N. Patrick, Jr.

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

Glenn Hiltpold, FCAS

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Name
 
Edward N. Patrick, Jr.

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

Name
Director of Actuarial Services

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

Title
 
Vice President, Underwriting

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Title
And in Armonk, New York, this 17th day of October, 2007.
ATTEST:
 
SWISS REINSURANCE AMERICA CORPORATION
/s/ Jeffrey Isaacson

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

 
/s/ Matthew Fay

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

Jeffrey Isaacson

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

Name
 
Matthew Fay

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

Name
Vice President
Member of Management

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

Title
 
Senior Vice President
Member of Senior Management

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

Title

ds
Safety POR327454 add#3

2. No. POR327454
    Addendum No. 3

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Exhibit 10.45