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Exhibit 10.2.4

FORM OF INVESTMENT MANAGEMENT AGREEMENT

        WHITE MOUNTAINS ADVISORS LLC, a Delaware limited liability company (the
"Advisor"), having an address at 2614 Boston Post Road, Suite 34A, Guilford,
Connecticut 06437, and [        ], a [        ] company (the "Client"), having
an address at [        ], hereby enter into this Investment Management
Agreement, dated as of [        ] (this "Agreement"), and hereby agree that the
Advisor shall act as discretionary adviser with respect to the assets of the
Client described below (the "Investment Account") on the following terms and
conditions:

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

        2.    Services of Advisor.    By execution of this Agreement the Advisor
accepts appointment as adviser for the Investment Account with full discretion
and agrees to supervise and direct the investments of the Investment Account in
accordance with the investment objectives, policies and restrictions described
in the investment guidelines to be furnished by the Client to the Advisor from
time to time (the "Investment Guidelines"). The Investment Guidelines are for
the stated purpose of assisting the Advisor in the performance of its investment
duties. The Advisor will manage the Investment Account in accordance with such
Investment Guidelines as provided to the Advisor from time to time. In addition,
the Advisor agrees to provide treasury management advisory services specific to
the Investment Account ("Treasury Management Services"), as directed by the
Client. The Treasury Management Services include, without limitation,
(i) executing investment transactions to support short-term treasury cash
requirements, (ii) settling inter-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 treasury transactions, (v) assisting the Client in evaluating
securities lending programs administered by custodians designated by the Client
and acceptable to the Advisor, and (vi) collaborating with the Client to provide
treasury transaction support to custodians and accounting servicing providers
designated by the Client and acceptable to the Advisor.

        3.    Discretionary Authority.    Advisor shall have full discretion and
authority, without obtaining any prior approval, as the Client's agent and
attorney-in-fact: (a) to make all investment decisions in respect of the
Investment Account on the Client's behalf and at the Client's sole risk; (b) to
buy, sell, exchange, convert, liquidate or otherwise trade in any stock, bond
and other securities in respect of the Investment Account; (c) to place orders
with respect to, and to arrange for, any of the foregoing; and (d) in
furtherance of the foregoing, to do anything which the Advisor shall deem
requisite, appropriate or advisable in connection therewith, including, without
limitation, the selection of such brokers, dealers, and others as the Advisor
shall determine in its absolute discretion.

        4.    Liability.    In the performance of its services, the Advisor will
not be liable for any error in judgment or any acts or failures to act except
those resulting from the Advisor's gross negligence, willful misconduct or
malfeasance. Nothing herein shall in any way constitute a waiver or limitation
of any right of any person under the federal securities laws. The Advisor shall
have no responsibility whatsoever for the management of any assets of the Client
other than the Investment Account.

        5.    Custody.    The assets of the Investment Account shall be held in
one or more separately identified accounts in the custody of one or more banks,
trust companies, brokerage firms or other entities designated by the Client and
acceptable to the Advisor. The Advisor will communicate its investment purchase,
sale and delivery instructions directly with the Client's custodian or other
qualified depository. The Client shall be responsible for all custodial
arrangements and the payment of all

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custodial charges and fees, and the Advisor shall have no responsibility or
liability with respect to custody arrangements or the acts, omissions or other
conduct of the custodians.

        6.    Brokerage.    When placing orders for the execution of
transactions for the Investment Account, the Advisor may allocate all
transactions to such brokers or dealers, for execution on such markets, at such
prices and commission rates, as are selected by the Advisor in its sole
discretion. In selecting brokers or dealers to execute transactions, the Advisor
need not solicit competitive bids and does not have an obligation to seek the
lowest available commission cost. It is not the Advisor's practice to negotiate
"execution only" commission rates, and, in negotiating commission rates, the
Advisor shall take into account the financial stability and reputation of
brokerage firms and brokerage and research services provided by such brokers.
The Client may be deemed to be paying for research provided or paid for by the
broker which is included in 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 specific securities, companies
or sectors; market, finance and economic studies and forecasts; financial
publications; statistics and pricing services; discussions with research
personnel; and software and data bases utilized in the investment management
process. The Client acknowledges that since commission rates are generally
negotiable, selecting brokers on the basis of considerations which are not
limited to applicable commission rates may at times result in higher transaction
costs than would otherwise be obtainable. The Advisor is hereby authorized to,
and the Client acknowledges that the Advisor may, aggregate orders on behalf of
the Investment Account with orders on behalf of other clients of the Advisor. In
such event, allocation of the securities purchased or sold, as well as expenses
incurred in the transaction, shall be made in a manner which the Advisor
considers to be the most fair and equitable to all of its clients, including the
Client.

        7.    Representations and Warranties.    

        a)    The Client represents, warrants 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's
governing documents and has been duly authorized by all necessary corporate or
other action; and

(iii)it will indemnify the Advisor and hold it harmless against any and all
losses, costs, claims and liabilities which the Advisor may suffer or incur
arising out of any material breach of these representations and warranties of
the Client.

        b)    The Advisor represents, warrants and agrees that:

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

(ii)it is registered as an investment adviser with the Securities and Exchange
Commission pursuant to the Investment Advisers Act of 1940, as amended (the
"Advisers Act");

(iii)entering into this Agreement has been duly authorized by all necessary
corporate or other action under the Advisor's governing document; and

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

        8.    Reports.    The Advisor shall provide the Client with reports
containing the status of the Investment Account at least monthly, and will
provide written advisory report letters to the Client on a quarterly basis. The
Advisor shall also provide the Client with preliminary valuation of the
Investment

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Account on a monthly basis. The preliminary valuation will be determined in
accordance with the Advisor's valuation policies and procedures, a copy of which
shall be provided to the Client as least annually. All records maintained
pursuant to this Agreement shall be subject to examination by the Client and by
persons authorized by it, or by appropriate governmental authorities, at all
times upon reasonable notice. The Advisor shall provide copies of trade tickets,
custodial reports and other records the Client reasonably requires for
accounting or tax purposes.

        9.    Management Fee, Treasury Management Fee and Expenses.    

        (a)   The Advisor will be paid a quarterly management and treasury
management fee (the "Management Fee") for its investment advisory and treasury
management services provided hereunder, determined in accordance with Schedule A
to this Agreement. During the term of this Agreement, the Management Fee shall
be billed and payable in arrears on a quarterly basis within 10 days after the
last day of each calendar quarter based upon the value of the Investment Account
as of the last day of the immediately preceding calendar quarter. The Management
Fee shall be pro-rated for any partial quarter. Capital inflows and outflows
result in an adjustment to the value of assets under management that serves as
the base of the Management Fee. This adjustment has the effect of time-weighting
capital flows in the account resulting in the Management Fee being properly
charged for only the period of time such assets are actually managed by the
Advisor. It is understood that, in the event that the Management Fee is to be
paid by the custodian out of the Investment Account, the Client will provide
written authorization to the custodian to pay the Management Fee directly from
the Investment Account.

        (b)   The Client shall be responsible for all expenses incurred directly
in connection with transactions effected on behalf of 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 transmittal of
Investment Account assets (other than research fees and expenses with respect to
the Investment Account).

        10.    Confidential Relationship.    All information and advice
furnished by either party to the other party pursuant to this Agreement shall be
treated by the receiving party as confidential and shall not be disclosed to
third parties except as required by law.

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

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

        13.    Services to Other Clients.    It is understood that the Advisor
acts as investment adviser to other clients and may give advice and take action
with respect to such clients that differs from the advice given or the action
taken with respect to the Investment Account. Nothing in this Agreement shall
restrict the right of the Advisor, its members, managers, officers, employees or
affiliates to perform investment management or advisory services for any other
person or entity, and the performance of such service for others shall not be
deemed to violate or give rise to any duty or obligation to the Client.

        14.    Investment by the Advisor for Its Own Account.    Nothing in this
Agreement shall limit or restrict the Advisor or any of its members, managers,
officers, employees or affiliates from buying,

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selling or trading any securities for its or their own account or accounts. The
Client acknowledges that the Advisor and its members, managers, officers,
employees, affiliates and other clients may at any time have, acquire, increase,
decrease or dispose of securities which are at or about the same time acquired
or disposed of for the account of the Client. The Advisor shall have no
obligation to purchase or sell for the Investment Account or to recommend for
purchase or sale by the Investment Account any security that the Advisor or its
members, managers, officers, employees or affiliates may purchase or sell for
itself or themselves or for any other client.

        15.    Proxies.    Subject to any other written instructions of the
Client, the Advisor is hereby appointed as the Client's agent and
attorney-in-fact in its discretion to vote, convert or tender in an exchange or
tender offer any securities in the Investment Account, to execute proxies,
waivers, consents and other instruments with respect to such securities, to
endorse, transfer or deliver such securities and to participate in or consent to
any plan of reorganization, merger, combination, consolidation, liquidation or
similar plan with reference to such securities, and the Advisor shall not incur
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 to
securities transactions or any other matters contemplated by this Agreement
shall be deemed duly given when delivered in writing, via electronic
communications or deposited by first-class mail to the following addresses:
(a) if to the Advisor, at its address set forth above, Attention: Chief
Financial Officer, or (b) if to the Client, at its address set forth above,
Attention: Chief Financial Officer. The Advisor or the Client may change its
address or specify a different manner of addressing itself by giving notice of
such change in writing to the other party.

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

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

        19.    Termination.    This Agreement shall continue in force in
accordance with paragraph 21, Effective Date and Term of this Agreement. During
such term, this Agreement may be terminated by the Client upon written notice to
the Advisor at least sixty (60) days prior to the date upon which such
termination is to become effectively only (i) for cause (including material
non-performance by the Advisor), (ii) if there is a change in control of the
Advisor (for this purpose, a change in control represents 50% or more of voting
interest of the Advisor) or (iii) if White Mountains Insurance Group, Ltd.'s
voting interest in Client falls below 50%. Following the end of the initial
fixed term and any extensions, as provided by paragraph 21, Effective Date and
Term of this Agreement, the Agreement may be terminated by either party 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 before the date of any
such termination. Upon termination of this Agreement, any accrued and unpaid
Management Fee and Treasury Management Fee hereunder shall be paid by the Client
to the Advisor.

        20.    Governing Law.    To the extent that the interpretation or effect
of this Agreement shall depend on state law, this Agreement shall be governed by
and construed in accordance with the laws of the State of New York.

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

        22.    Receipt of Disclosure Statement.    The Client acknowledges
receipt of a copy of Part II of the Advisor's Form ADV in compliance with
Rule 204-3(b) under the Investment Advisers Act of 1940, as amended, more than
48 hours prior to the date of execution of this Agreement. The Advisor shall
annually and without charge, upon request by the Client, deliver to the Client
the current version of such form or a written document containing at least the
information then required to be contained in such form.

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

        IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed by their respective duly authorized representatives as of the date
first written above.

ADVISER:
   
WHITE MOUNTAINS ADVISORS LLC
   
  CLIENT
   
[        ]
   
By:  

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  By:  

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Print: Mark J. Plourde

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  Print:  

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Title: Chief Financial Officer and Treasurer

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  Title:  

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SCHEDULE B

FEE SCHEDULE

1.Investment Account.

Assets Under Management

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  Value

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  Annual Fee

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  Quarterly Fee

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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—$1.1999 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 calculating the fee for Investment Grade Fixed Income
investments as provided above, the assets under management of OneBeacon
Insurance Group, Ltd. and all of its direct and indirect subsidiaries will be
aggregated.

2.Treasury Management Services.    The Advisor will be paid a quarterly fee for
the Treasury Management Services computed at the annual rate of 1.75 basis
points (0.0175%) of the aggregate value of the net assets of the Client's
Investment Account on an annual basis utilizing the methodologies described in
Paragraph 1 of Exhibit A. In the first year of the Agreement, the Treasury
Management Services fee shall not exceed $500,000 on an annual basis.

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Exhibit 10.2.4