FORM 4 [ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).         
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES
                                                                                  
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
                      
1. Name and Address of Reporting Person * SRB Corp 2. Issuer Name and Ticker or Trading Symbol SAFETY INSURANCE GROUP INC [ SAFT ] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable)_____ Director                    __X__ 10% Owner
_____ Officer (give title below)    _____ Other (specify below)
(Last)         (First)         (Middle)
125 HIGH STREET
3. Date of Earliest Transaction (MM/DD/YYYY)
3/20/2020
(Street)
BOSTON, MA 02110
(City)       (State)       (Zip)
4. If Amendment, Date Original Filed (MM/DD/YYYY)
 
6. Individual or Joint/Group Filing (Check Applicable Line) ___ Form filed by One Reporting Person
_ X _ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Trans. Date 2A. Deemed Execution Date, if any 3. Trans. Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
Code V Amount (A) or (D) Price
Common Stock  3/20/2020    P    17590  A $71.32  1581233 (1)(2)(3)(4)(5) I  See (1)(2)(3)(4)(5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Trans. Date 3A. Deemed Execution Date, if any 4. Trans. Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
6. Date Exercisable and Expiration Date 7. Title and Amount of Securities Underlying Derivative Security
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Explanation of Responses:
(1)  This Form 4 is being jointly filed by SRB Corporation, a Massachusetts corporation ("SRB"), and The Plymouth Rock Company Incorporated, a Massachusetts corporation ("PRC"), and each shall be deemed a Reporting Person. SRB is a direct, wholly-owned subsidiary of PRC and acts as investment manager to PRC and, in such capacity, may be deemed to have voting and dispositive power over the shares of Common Stock reported on this Form 4. SRB disclaims beneficial ownership of the shares of Common Stock reported on this Form 4, and this report shall not be deemed an admission that SRB is a beneficial owner of such shares for purposes of Section 16 or for any other purpose. (Continued in Footnote 2)
(2)  The Reporting Persons are making this single joint filing because they may be deemed a "group" within the meaning of Section 13(d)(3) of the Securities Act of 1934, as amended. This joint filing shall not, however, be deemed an affirmation that a group exists among the Reporting Persons for the purposes of the Securities Exchange Act of 1934 or for any other purpose and each Reporting Person expressly disclaims beneficial ownership of any securities beneficially owned by any other person.
(3)  PRC holds 17,317 of the shares of Common Stock reported on this Form 4. The following subsidiaries of PRC hold in the aggregate 565,978 shares of the Common Stock reported on this Form 4: Plymouth Rock Security Corporation, a Massachusetts security corporation ("PRSC"); Plymouth Rock Assurance Corporation, a Massachusetts corporation ("PRAC"); Plymouth Rock Assurance Preferred Corporation, a New York corporation ("PRAPC"); Plymouth Rock Assurance Corporation of New York, a New York corporation ("PRACNY"); Pilgrim Insurance Company, a Massachusetts corporation; ("Pilgrim"); Bunker Hill Insurance Company, a Massachusetts corporation ("BHIC"); Bunker Hill Insurance Casualty Company, a Massachusetts corporation ("BHICC"); Bunker Hill Preferred Insurance Company, a Massachusetts corporation ("BHPREFIC"); Bunker Hill Property Insurance Company, a Massachusetts corporation ("BHPIC"); (Continued in Footnote 4)
(4)  and Bunker Hill Security Insurance Company, a Massachusetts corporation ("BHSIC"). PRSC, PRAC, and BHIC are direct wholly-owned subsidiaries of PRC. PRAPC and PRACNY are direct wholly-owned subsidiaries of PRAC. Pilgrim is a direct wholly-owned subsidiary of SRB. BHICC, BHPREFIC, BHPIC, and BHSIC are direct wholly-owned subsidiaries of BHIC. Palisades Safety and Assurance Association, a New Jersey reciprocal insurance exchange ("PSIA") , is managed by a subsidiary of PRC. PSIA and the following subsidiaries of PSIA hold in the aggregate 997,938 shares of the Common Stock reported on this Form 4: High Point Safety and Insurance Company, a New Jersey corporation ("HPSIC"); High Point Property and Casualty Insurance Company, a New Jersey corporation ("HPPCIC"); High Point Preferred Insurance Company, a New Jersey corporation ("HPPIC"); Palisades Insurance Company, a New Jersey corporation ("PICNJ"); (Continued in Footnote 5)
(5)  Twin Lights Insurance Company , a New Jersey corporation ("TLIC"); and Teachers Auto Insurance Company of New Jersey, a New Jersey corporation ("TAIC"). HPSIC, HPPIC, TLIC, and TAIC are direct wholly-owned subsidiaries of HPPCIC, which is a direct wholly-owned subsidiary of PSIA, as is PICNJ. PRC disclaims beneficial ownership of the shares of Common Stock reported on this Form 4 except to the extent of its pecuniary interest therein, and this report shall not be deemed an admission that PRC is a beneficial owner of such shares for purposes of Section 16 or for any other purposes.

Reporting Owners
Reporting Owner Name / Address
Relationships
Director 10% Owner Officer Other
SRB Corp
125 HIGH STREET
BOSTON, MA 02110

X

Plymouth Rock Co Inc
125 HIGH STREET
BOSTON, MA 02110

X


Signatures
/s/ F.C. Childs 3/20/2020
**Signature of Reporting Person Date