**Exhibit 10.2.3**

**INVESTMENTMANAGEMENT AGREEMENT**

**WHITEMOUNTAINS ADVISORS LLC**, a Delaware limited liability company (the “Advisor”),having an address at 370 Church Street, Guilford, Connecticut 06437, and                                                                           , a                      corporation (the “Client”), having an address at One Beacon Street,Boston, Massachusetts 02108, hereby enter into this Investment ManagementAgreement, dated as of November 14, 2006 (this “Agreement”), and herebyagree that the Advisor shall act as discretionary adviser with respect to theassets of the Client described below (the “Investment Account”) on thefollowing terms and conditions:

1.                                       Investment Account.  The Investment Account shall consist of cash andthe securities of the Client.

2.                                       Services of Advisor.  By execution of this Agreement, the Advisoraccepts appointment as adviser for the Investment Account with full discretionand agrees to supervise and direct the investments of the Investment Account inaccordance with the investment objectives, policies and restrictions describedin the investment guidelines to be furnished by the Client to the Advisor fromtime to time (the “Investment Guidelines”).  The Investment Guidelines are for the statedpurpose of assisting the Advisor in the performance of its investmentduties.  The Advisor will manage theInvestment Account in accordance with such Investment Guidelines as provided tothe Advisor from time to time.  Inaddition, the Advisor agrees to provide treasury management advisory servicesspecific to the Investment Account (“Treasury Management Services”), asdirected by the Client.  The TreasuryManagement Services include, without limitation, (i) executing investmenttransactions to support short-term treasury cash requirements, (ii) settlinginter-company and dividend treasury transactions with cash and securities,(iii) settling quarterly tax liability payments from the Investment Account,(iv) providing preliminary valuation for securities supporting treasurytransactions, (v) assisting the Client in evaluating securities lendingprograms administered by custodians designated by the Client and acceptable tothe Advisor, and (vi) collaborating with the Client to provide treasurytransaction support to custodians and accounting servicing providers designatedby the Client and acceptable to the Advisor.

3.                                       Discretionary Authority.  Advisor shall have full discretion andauthority, without obtaining any prior approval, as the Client’s agent andattorney-in-fact: (a) to make all investment decisions inrespect of the Investment Account on the Client’s behalf and at the Client’ssole risk; (b) to buy, sell, exchange, convert, liquidate or otherwisetrade in any stock, bond and other securities in respect of the InvestmentAccount; (c) to place orders with respect to, and to arrange for, any ofthe foregoing; and (d) in furtherance of the foregoing, to do anythingwhich the Advisor shall deem requisite, appropriate or advisable in connectiontherewith, including, without limitation, the selection of such brokers,dealers, and others as the Advisor shall determine in its absolutediscretion.  

4.                                       Liability.  In the performance of its services, theAdvisor will not be liable for any error in judgment or any acts or failures toact except those resulting from the Advisor’s gross negligence, willfulmisconduct or malfeasance.  Nothingherein shall in any way constitute a waiver or limitation of any right of anyperson under the federal securities laws. The Advisor shall have no

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responsibility whatsoever forthe management of any assets of the Client other than the Investment Account.

5.                                       Custody.  The assets of the Investment Account shall beheld in one or more separately identified accounts in the custody of one ormore banks, trust companies, brokerage firms or other entities designated bythe Client and acceptable to the Advisor. The Advisor will communicate its investment purchase, sale and deliveryinstructions directly with the Client’s custodian or other qualifieddepository.  The Client shall beresponsible for all custodial arrangements and the payment of all custodialcharges and fees, and the Advisor shall have no responsibility or liabilitywith respect to custody arrangements or the acts, omissions or other conduct ofthe custodians.

6.                                       Brokerage.  When placing orders for the execution oftransactions for the Investment Account, the Advisor may allocate alltransactions to such brokers or dealers, for execution on such markets, at suchprices and commission rates, as are selected by the Advisor in its solediscretion.  In selecting brokers ordealers to execute transactions, the Advisor need not solicit competitive bidsand does not have an obligation to seek the lowest available commissioncost.  It is not the Advisor’s practiceto negotiate “execution only” commission rates, and, in negotiating commissionrates, the Advisor shall take into account the financial stability andreputation of brokerage firms and brokerage and research services provided bysuch brokers.  The Client may be deemedto be paying for research provided or paid for by the broker which is includedin the commission rate although the Client may not, in any particular instance,be the direct or indirect beneficiary of the research services provided.  Research furnished by brokers may include,but is not limited to, written information and analyses concerning specificsecurities, companies or sectors; market, finance and economic studies and forecasts;financial publications; statistics and pricing services; discussions withresearch personnel; and software and data bases utilized in the investmentmanagement process.  The Clientacknowledges that since commission rates are generally negotiable, selectingbrokers on the basis of considerations which are not limited to applicablecommission rates may at times result in higher transaction costs than wouldotherwise be obtainable.  The Advisor ishereby authorized to, and the Client acknowledges that the Advisor may,aggregate orders on behalf of the Investment Account with orders on behalf ofother clients of the Advisor.  In suchevent, allocation of the securities purchased or sold, as well as expensesincurred in the transaction, shall be made in a manner which the Advisorconsiders to be the most fair and equitable to all of its clients, includingthe Client.

                                                7.                                       Representations and Warranties.

(a)          TheClient represents, warrants, covenants and agrees that:

(i)                             it has full legal power and authority to enter into this Agreement;

(ii)                          the appointment of the Advisor hereunder is permitted by the Client’sgoverning documents and has been duly authorized by all necessary corporate orother action, and

(iii)                       it will indemnify the Advisor and hold it harmless against any andall  losses, costs, claims andliabilities which the Advisor may suffer or

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incur arising out of any material breach of these representations andwarranties of the Client.

(b)         The Advisor represents, warrants, covenantsand agrees that:

(i)                             it has full legal power and authority toenter into this Agreement;

(ii)                          it is registered as an investment adviserwith the Securities and Exchange Commission pursuant to the Investment AdvisersAct of 1940, as amended (the “Advisers Act”);

(iii)                       entering into this Agreement has been duly authorizedby all necessary corporate or other action under the Advisor’s governingdocument, and

(iv)                      it will indemnify the Client and hold itharmless against any and all losses, costs, claims and liabilities which theClient may suffer or incur arising out of any material breach of anyrepresentations and warranties of the Advisor.

8.                                       Reports.  The Advisor shall provide the Client withreports containing the status of the Investment Account at least monthly, andwill provide written advisory report letters to the Client on a quarterlybasis.  The Advisor shall also providethe Client with preliminary valuation of the Investment Account on a monthlybasis.  The preliminary valuation will bedetermined in accordance with the Advisor’s valuation policies and procedures,a copy of which shall be provided to the Client at least annually.  All records maintained pursuant to thisAgreement shall be subject to examination by the Client and by personsauthorized by it, or by appropriate governmental authorities, at all times uponreasonable notice.  The Advisor shallprovide copies of trade tickets, custodial reports and other records the Clientreasonably requires for accounting or tax purposes.

9.                                       Management Fee,Treasury Management Fee and Expenses.

(a)   The Advisor will be paid a quarterlymanagement and treasury management fee (the “Management Fee”) for itsinvestment advisory and treasury management services provided hereunder,determined in accordance with Schedule A to this Agreement.  During the term of this Agreement, theManagement Fee shall be billed and payable in arrears on a quarterly basiswithin 10 days after the last day of each calendar quarter based upon the valueof the Investment Account as of the last day of the immediately precedingcalendar quarter.  The Management Feeshall be pro-rated for any partial quarter. Capital inflows and outflows result in an adjustment to the value ofassets under management that serves as the base of the Management Fee.  This adjustment has the effect of time-weightingcapital flows in the account resulting in the Management Fee being properlycharged for only the period of time such assets are actually managed by theAdvisor.  It is understood that, in theevent that the Management Fee is to be paid by the custodian out of theInvestment Account, the Client will provide written authorization to thecustodian to pay the Management Fee directly from the Investment Account.

(b)   The Client shall be responsible for allexpenses incurred directly in connection with transactions effected on behalfof the Client pursuant to this Agreement and shall include:  custodial fees; PAM accounting service fees,Charles River compliance service fees, investment expenses such as commissions;and other expenses reasonably related to the purchase, sale or 

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transmittal of InvestmentAccount assets (other than research fees and expenses with respect to theInvestment Account).

10.                                 ConfidentialRelationship.  All information and advicefurnished by either party to the other party pursuant to this Agreement shallbe treated by the receiving party as confidential and shall not be disclosed tothird parties except as required by law.

11.                                 Assignment.  This agreement may not beassigned (within the meaning of the Advisers Act) by either party without thewritten consent of the other party, and any assignment without such consentshall automatically cause the termination hereof.

12.                                 Directions to theAdvisor.  All directions by or on behalf of the Clientto the Advisor shall be in writing signed by or on behalf of the Client.  The Advisor shall be fully protected inrelying upon any such writing which the Advisor believes to be genuine andsigned or presented by the proper person or persons, shall be under no duty tomake any investigation or inquiry as to any statement contained therein and mayaccept the same as conclusive evidence of the truth and accuracy of thestatements therein contained.

13.                                 Services to OtherClients.  It is understood that the Advisor acts asinvestment adviser to other clients and may give advice and take action withrespect to such clients that differs from the advice given or the action takenwith respect to the Investment Account. Nothing in this Agreement shall restrict the right of the Advisor, itsmembers, managers, officers, employees or affiliates to perform investmentmanagement or advisory services for any other person or entity, and theperformance of such service for others shall not be deemed to violate or giverise to any duty or obligation to the Client.

14.                                 Investment by theAdvisor for Its Own Account.  Nothing in thisAgreement shall limit or restrict the Advisor or any of its members, managers,officers, employees or affiliates from buying, selling or trading anysecurities for its or their own account or accounts.  The Client acknowledges that the Advisor andits members, managers, officers, employees, affiliates and other clients may atany time have, acquire, increase, decrease or dispose of securities which areat or about the same time acquired or disposed of for the account of theClient.  The Advisor shall have noobligation to purchase or sell for the Investment Account or to recommend forpurchase or sale by the Investment Account any security that the Advisor or itsmembers, managers, officers, employees or affiliates may purchase or sell foritself or themselves or for any other client.

15.                                 Proxies.  Subject to any other written instructions ofthe Client, the Advisor is hereby appointed as the Client’s agent andattorney-in-fact in its discretion to vote, convert or tender in an exchange ortender offer any securities in the Investment Account, to execute proxies,waivers, consents and other instruments with respect to such securities, toendorse, transfer or deliver such securities and to participate in or consentto any plan of reorganization, merger, combination, consolidation, liquidationor similar plan with reference to such securities, and the Advisor shall notincur any liability to the Client by reason of any exercise of, or failure to exercise,any such discretion.

16.                                 Notices.  All notices and instructions with respect tosecurities transactions or any other matters contemplated by this Agreementshall be deemed duly given when delivered in writing, via electroniccommunications or deposited by first-class mail to the following addresses:

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(a) if to the Advisor, at itsaddress set forth above, Attention: Chief Financial Officer, or (b) if to theClient, at its address set forth above, Attention: Chief FinancialOfficer.  The Advisor or the Client maychange its address or specify a different manner of addressing itself by givingnotice of such change in writing to the other party.

17.                                 Entire Agreement;Amendment.  This Agreement sets forth the entireagreement of the parties with respect to management of the Investment Account,supersedes any previous Investment Management Agreement between the Advisor andthe Client and shall not be amended except by an instrument in writing signedby the parties hereto.

18.                                 Arbitration.  Any controversy or claim arising out of orrelating to this Agreement, or the breach of the same, shall be settled byarbitration in accordance with the rules of the American ArbitrationAssociation, and judgment upon the award rendered by the arbitrators may beentered in any court having jurisdiction. All arbitration expenses shall be borne equally by the Advisor and theClient.

19.                                 Termination.  This Agreement shall continue in force inaccordance with paragraph 21, Effective Date and Term of thisAgreement.  During such term, thisAgreement may be terminated by the Client upon written notice to the Advisor atleast sixty (60) days prior to the date upon which such termination is tobecome effective only (i) for cause (including material non-performance by theAdvisor), (ii) if there is a change in control of the Advisor (for thispurpose, a change in control represents 50% or more of voting interest of theAdvisor) or (iii) if White Mountains Insurance Group, Ltd.’s voting interest inClient falls below 50%.  Following theend of the initial fixed term and any extensions, as provided by paragraph 21, EffectiveDate and Term of this Agreement, the Agreement may be terminated by eitherparty without penalty by written notice to the other party at least sixty (60)days prior to the date upon which such termination is to become effective,provided that the Client shall honor any trades executed but not settled beforethe date of any such termination.  Upontermination of this Agreement, any accrued and unpaid Management Fee andTreasury Management Fee hereunder shall be paid by the Client to the Advisor.

20.                                 Governing Law.  Tothe extent that the interpretation or effect of this Agreement shall depend onstate law, this Agreement shall be governedby and construed in accordance with the laws of the State of New York.

21.                                 Effective Date andTerm.  This Agreement shall become effective on thefirst date written above for an initial fixed term of three years, which willbe extendible by the Client for an additional one year (a fourth year) at/priorto the end of the second year of the term, and if so extended, for a secondadditional year (a fifth year) at/prior to the end of the third year of theterm.

22.                                 Receipt of DisclosureStatement.  The Client acknowledges receipt of a copy ofPart II of the Advisor’s Form ADV in compliance with Rule 204-3(b) under theInvestment Advisers Act of 1940, as amended, more than 48 hours prior to thedate of execution of this Agreement.  TheAdvisor shall annually and without charge, upon request by the Client, deliverto the Client the current version of such form or a written document containingat least the information then required to be contained in such form.

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23.                                 Counterparts.  This Agreement may be executed in twocounterparts, each one of which shall be deemed to be an original.

IN WITNESS WHEREOF, theparties hereto have caused this Agreement to be executed by their respectiveduly authorized representatives as of the date first written above.
| **ADVISOR:**                      |                            | **CLIENT:**               |       |                                          |
|-----------------------------------|---------------------------------|---------------------------|------------|-----------------------------------------------|
|                              |                            |                      |       |                                          |   |   |
| **WHITE MOUNTAINS ADVISORS, LLC** |                            | **[see client schedule]** | ** ** | ** **                                    |
|                              |                            |                      |       |                                          |   |   |
|                              |                            |                      |       |                                          |   |   |
| By:                               | /s/ Mark K. Dorcus              |                      | By:        | /s/ Frederick J. Turcotte                     |   |   |
|                              |                            |                      |       |                                          |   |   |
|                              |                            |                      |       |                                          |   |   |
| Print:                            | Mark K. Dorcus                  |                      | Print:     | Frederick J. Turcotte                         |   |   |
|                              |                            |                      |       |                                          |   |   |
| Title:                            | President and Managing Director |                      | Title:     | Vice President, Investor Relations, Treasurer |
|                              |                            |                      |       | and Tax Director                              |
|                                   |                                 |                           |            |                                               |  |  |  |  |

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**SCHEDULE A**

**FEE SCHEDULE**

1.                                       Investment Account.
| Assets Under Management                                               | ** ** | **Value** | ** ** | **Annual Fee**                | ** ** | **Quarterly Fee**                | ** ** |
|---------------------------------------------------------------------------------|------------|-----------|------------|------------------------------------|------------|---------------------------------------|------------|
| Investment Grade Fixed  Income:                                                 |       |      |       |                               |       |                                  |       |
| — Up to $999  million                                                      |       | Market    |       | 10.0  basis points (0.1% or 0.001) |       | 2.5  basis points (0.025% or 0.00025) |       |
| — Next $1 -  $1.999 billion                                                |       | Market    |       | 8.5  basis points                  |       | 2.125  basis points                   |       |
| — Amounts over  $2 billion                                                 |       | Market    |       | 7.5  basis points                  |       | 1.875  basis points                   |       |
| High Yield Debt                                                                 |       | Market    |       | 25.0  basis points                 |       | 6.25  basis points                    |       |
| Fully Funded Hedge  Funds, Limited Partnerships and Limited Liability Companies |       | Market    |       | 100.0  basis points                |       | 25.0  basis points                    |       |
| Private Equities and  Other Deferred Fundings:                                  |       |      | ** ** | ** **                         | ** ** | ** **                            | ** ** |
| — First 2 Years  of Fund’s Life                                       |       | Committed |       | 100.0  basis points                |       | 25.0  basis points                    |       |
| — Thereafter                                                               |       | Market    |       | 100.0 basis points                 |       | 25.0 basis points                     |       |

 

For purposes of calculatingthe fee for Investment Grade Fixed Income investments as provided above, theassets under management of OneBeacon Insurance Group, Ltd. and all of itsdirect and indirect subsidiaries will be aggregated.

2.                     Treasury Management Services.  TheAdvisor will be paid a quarterly fee for the Treasury Management Servicescomputed at the annual rate of 1.75 basis points (0.0175%) of the aggregatevalue of the net assets of the Client’s Investment Account on an annual basisutilizing the methodologies described in Paragraph 1 of Exhibit A.  In the first year of the Agreement, theTreasury Management Services fee shall not exceed $500,000 on an annual basis.

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| Client Schedule:                       |
|----------------------------------------|
|                                   |
|                                   |
| Pennsylvania General Insurance Company |
|                                   |
| OneBeacon Insurance Group, Ltd.        |
|                                   |
| Potomac Insurance Company              |

 

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