Exhibit 10.7

AMENDED AND RESTATED TAX SHARING AGREEMENT
(AS OF DECEMBER 19, 2006)

This Amended and Restated Tax Sharing Agreement (the "Agreement") is made as of this 19th day of December 2006 by and among Zenith National
Insurance Corp.("Zenith National") and its subsidiaries, Zenith Insurance Company, ZNAT Insurance Company, Zenith Development Corp., Zenith of Nevada, Inc., Zenith Insurance Management
Services, Inc. and 1390 Main Street, LLC (the "Existing Subsidiaries").

WHEREAS,
Zenith National is the common parent of an affiliated group of corporations, as defined in section 1504 (a) of the Internal Revenue Code of 1986, as amended (the
"Code"), of which the Existing Subsidiaries are members;

WHEREAS,
Zenith National, on behalf of its affiliated group, has filed for previous taxable years consolidated federal income tax returns in accordance with section 1501 of the
Code and is required to file consolidated federal income tax returns for subsequent taxable years;

WHEREAS,
Zenith National and the Existing Subsidiaries had entered into an Amended and Restated Tax Sharing Agreement as of January 1, 1991, which has been subsequently amended
from time to time (as so amended, the "Existing Agreement"), and which provides for the allocation of the consolidated federal income tax among the parties and certain related matters;

WHEREAS,
Zenith National, on behalf of its affiliated group or any sub-group of the affiliated group has filed, or may elect to file in the future, combined or consolidated
State Income Tax Returns (as hereinafter defined) with those states that require or allow such combined or consolidated returns;

WHEREAS,
the parties now wish to provide for the allocation among them of consolidated or combined state income tax liability and certain related matters; and

WHEREAS,
Zenith National and the Existing Subsidiaries now desire to amend and restate the Existing Agreement to consolidate the documents that constitute the Existing Agreement into a
single document and also to provide for the allocation among them of consolidated or combined state income tax liability.

NOW,
THEREFORE, in consideration of the foregoing premises and of the mutual covenants and agreements contained herein, the parties agree that the Existing Agreement is hereby amended
and restated in its entirety, as follows:



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(Signature
on following page)

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IN
WITNESS WHEREOF, the parties hereto have entered into this Agreement effective as of the date first above written.

| |  | ZENITH NATIONAL INSURANCE CORP.           
| |  | ------------------------------------------
| |  | By:                                       
| |  | ZENITH INSURANCE COMPANY                  
| |  | By:                                       
| |  | ZNAT INSURANCE COMPANY                    
| |  | By:                                       
| |  | ZENITH DEVELOPMENT CORP.                  
| |  | By:                                       
| |  | ZENITH OF NEVADA, INC.                    
| |  | By:                                       
| |  | ZENITH INSURANCE MANAGEMENT
SERVICES, INC.
| |  | By:                                       
| |  | 1390 MAIN STREET, LLC                     
| |  | By:                                       
| |  | By:                                       

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EXHIBIT A        CONSENT OF NEW SUBSIDIARY

The undersigned hereby agrees, subject to the agreement or approval of the appropriate regulatory authorities (as required by law), to be bound as a Subsidiary by
the attached Amended and Restated Tax Sharing Agreement (as of December 19, 2006) (the "Agreement"). By signing this Consent, the undersigned will have all rights and obligations of a
Subsidiary under the Agreement as of the date the undersigned became a Member (as defined in the Agreement).

| |  | By:
| |  | ---

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