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                      SUPERIOR NATIONAL INSURANCE GROUP, INC.
                                     AS ISSUER
                                          
                                          
                              WILMINGTON TRUST COMPANY
                                     AS TRUSTEE
                                          
                                          
                                          
                                          
                                          
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                            FIRST SUPPLEMENTAL INDENTURE

                            Dated as of November 17, 1998


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                                      To

       The Senior Subordinated Indenture Dated as of December 3, 1997
       Between Superior National Insurance Group, Inc., as Issuer, and
              Wilmington Trust Company, as Trustee, Relating to
                   $108,325,000 Aggregate Principal Amount
                of 10 3/4% Senior Subordinated Notes due 2017


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     FIRST SUPPLEMENTAL INDENTURE, dated as of November 17, 1998 (this 
"Supplemental Indenture"), between Superior National Insurance Group, Inc., a 
corporation organized under the law of the State of Delaware (the "Company"), 
and Wilmington Trust Company, a Delaware banking corporation (the "Trustee"), 
as Trustee under the Indenture (as defined below).  Capitalized terms used 
and not defined herein shall have the same meanings given to them in the 
Indenture unless otherwise indicated.

     WHEREAS, the Company and the Trustee are parties to that certain Senior 
Subordinated Indenture, dated as of December 3, 1997 (the "Indenture"), 
pursuant to which the Company issued its 10 3/4% Senior Subordinated Notes due 
2017;

     WHEREAS, pursuant to Section 9.2 of the Indenture, the Company and the 
Trustee, with the consent of the Holders of not less than a majority in 
aggregate principal amount of the Outstanding Securities affected thereby, 
may modify the Indenture to, among other things, modify the rights of the 
Holders under the Indenture in the manner set forth herein;

     WHEREAS, pursuant to Section 9.2 of the Indenture, no such modification 
to the Indenture may be made without the additional prior consent of the 
holders of at least a majority of the outstanding aggregate liquidation 
preference of the 10 3/4% Trust Preferred Securities (the "Preferred 
Securities") of Superior National Capital Trust I (the "Trust");

     WHEREAS, pursuant to a Consent Solicitation Statement, dated October 30, 
1998, of the Company and the Trust, the requisite prior consent of the 
holders of the Preferred Securities has been obtained to effect the 
modification of the Indenture in the manner described herein (the "Waiver") 
by way of this Supplemental Indenture;

     WHEREAS, Holders of not less than a majority in outstanding aggregate 
principal amount of the Outstanding Securities have consented to the Waiver; 
and

     WHEREAS, by entering into this Supplemental Indenture, the Company and 
the Trustee have consented to modify the Indenture in accordance with the 
terms and conditions set forth herein;

     NOW, THEREFORE, in consideration of the foregoing and for other good and 
valuable consideration, the receipt and sufficiency of which is hereby 
acknowledged, the Company and the Trustee hereby agree for the benefit of 
each other and the equal and ratable benefit of the holders of the Securities 
as follows:

     1.   MODIFICATION TO THE INDENTURE.  On the Effective Date (as 
hereinafter defined) the Indenture is modified as follows:

          (a)  Section 10.8(a) of the Indenture is hereby waived to the extent
required to permit the Company to Incur, for purposes of the Company's
acquisition of Business Insurance Group, Inc., 

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up to $110,000,000 in aggregate principal amount of Senior Indebtedness 
through a public or private offering of senior notes or through a credit 
facility or other borrowing arrangement with a lender or lenders, or a 
combination thereof (the "Senior Debt Financing").

          (b)  After giving effect to the Incurrence of the Indebtedness 
pursuant to the Senior Debt Financing, the Company will be deemed, for all 
purposes of the Indenture, as having Incurred such Indebtedness pursuant to 
Section 10.8(a) of the Indenture.

     2.   COMPLIANCE WITH AND FULFILLMENT OF CONDITIONS PRECEDENT.  All 
conditions precedent to the execution and delivery of this Supplemental 
Indenture have been met, including, but not limited to (a) an Opinion of 
Counsel and/or an Officers' Certificate (i) as to the due authorization, 
execution and delivery of the Supplemental Indenture by the Company, (ii) as 
to the enforceability of the Supplemental Indenture, (iii) as to the due 
authorization of the Supplemental Indenture by the Indenture, and (iv) as to 
the satisfaction of all conditions precedent to the execution, delivery and 
performance of the Supplemental Indenture; (b) that Holders of not less than 
a majority in principal amount of the Outstanding Securities affected by this 
Supplemental Indenture have consented (in accordance with the terms of the 
Indenture) and that such consent has been delivered to the Company and the 
Trustees; and (c) the adoption of a Board Resolution of the Company 
authorizing this Supplemental Indenture.

     3.   EFFECTIVE DATE.  This Supplemental Indenture shall become effective 
on the date (the "Effective Date") on which the Company and the Trustee 
execute and deliver this Supplemental Indenture.

     4.   CONSTRUCTION.  For all purposes of this Supplemental Indenture, 
except as otherwise herein expressly provided or unless the context otherwise 
requires: (i) the terms and expressions used herein shall have the same 
meanings as corresponding terms and expressions used in the Indenture; and 
(ii) the words "herein," "hereof" and "hereby" and other words of similar 
import used in this Supplemental Indenture refer to this Supplemental 
Indenture as a whole and not to any particular Section hereof.

     5.   TRUSTEE ACCEPTANCE.  The Trustee accepts the modification of the 
Indenture effected by this Supplemental Indenture, but only upon the terms 
and conditions set forth in the Indenture, as hereby amended, including the 
terms and provisions defining and limiting the liabilities and 
responsibilities of the Trustee in the performance of its duties and 
obligations under the Indenture, as hereby amended.  Without limiting the 
generality of the foregoing, the Trustee has no responsibility for the 
correctness of the recitals of fact herein contained which shall be taken as 
the statements of the Company, and makes no representations as to the 
validity or enforceability against the Company.

     6.   INDENTURE RATIFIED.  Except as expressly amended hereby, the Indenture
is in all respects ratified and confirmed and all the terms, conditions and
provisions thereof shall remain in 

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full force and effect.  All protection afforded the Trustee by the Indenture 
shall also be afforded to the Trustee in connection with its execution, 
delivery and performance of this Supplemental Indenture.

     7.   HOLDERS BOUND.  This Supplemental Indenture shall form a part of 
the Indenture for all purposes, and every Holder of the Securities heretofore 
or hereafter authenticated and delivered shall be bound hereby.

     8.   CONFLICT WITH TRUST INDENTURE ACT.  If any provision hereof limits, 
qualifies or conflicts with a provision of the Trust Indenture Act that is 
required or deemed under the Trust Indenture Act to be part of and govern 
this Supplemental Indenture, the latter provision shall control.  If any 
provision of this Supplemental Indenture modifies or excludes any provision 
of the Trust Indenture Act that may be so modified or excluded, the latter 
provision shall be deemed to apply to this Supplemental Indenture as so 
modified or to be excluded, as the case may be.

     9.   HEADINGS.  The Section headings herein are for convenience only and 
shall not affect the construction hereof.

     10.  SUCCESSORS AND ASSIGNS.  All covenants and agreements in this 
Supplemental Indenture by the Company shall bind its respective successors 
and assigns, whether so expressed or not.

     11.  SEPARABILITY CLAUSE.  In case any provision in this Supplemental 
Indenture shall be invalid, illegal or unenforceable, the validity, legality 
and enforceability of the remaining provisions shall not in any way be 
affected or impaired thereby. 

     12.  GOVERNING LAW.  THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY 
AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

     13.  DUPLICATE ORIGINALS.  The parties may sign any number of copies of 
this Supplemental Indenture.  Each signed copy shall be an original, but all 
of them together represent the same agreement.

     14.  NO RECOURSE AGAINST OTHERS.  A Director, officer, employee, 
stockholder or incorporator as such, of the Company shall not have any 
liability for any obligations of the Company under this Supplemental 
Indenture for any claims based on, in respect of or by reason of such 
obligations or their creation.

     15.  COUNTERPARTS.  This Supplemental Indenture may be executed in any 
number of counterparts, each of which when so executed shall be deemed to be 
an original, and all of such counterparts shall together constitute one and 
the same instrument.

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     IN WITNESS WHEREOF, the Company and the Trustee have caused this 
Supplemental Indenture to be duly executed as of the date first above written.

                                   COMPANY:

                                   SUPERIOR NATIONAL INSURANCE GROUP, INC.,
                                   a Delaware corporation

                                   By    /s/  J. CHRIS SEAMAN
                                     ----------------------------------------
                                       Name:  J. Chris Seaman
                                       Title:  Executive Vice President and
                                           Chief Financial Officer



                                   TRUSTEE:

                                   WILMINGTON TRUST COMPANY,
                                   a Delaware banking corporation, as Trustee 

                                   By    /s/   ANNE ROBERTS
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                                       Name:   Anne Roberts
                                       Title:  Sr. Financial Svc. Officer


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