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                                                                     Exhibit 4.2



                                                                  EXECUTION COPY




                        ASPEN INSURANCE HOLDINGS LIMITED




                  --------------------------------------------
                  AMENDED AND RESTATED INSTRUMENT CONSTITUTING
                       OPTIONS TO SUBSCRIBE FOR SHARES IN
                        ASPEN INSURANCE HOLDINGS LIMITED
                  --------------------------------------------

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                                                                               2


                                    CONTENTS

CLAUSE                                                                      PAGE

1.     Interpretation.........................................................1
2.     Constitution And Form Of Options......................................12
3.     Register And Option Certificates......................................12
4.     Subscription Rights And Mechanics Of Exercise.........................13
5.     Adjustment And Anti-Dilution..........................................18
6.     Undertakings Of The Company...........................................22
7.     Winding Up Of The Company.............................................23
8.     Transfer Of Options...................................................24
9.     Repurchase............................................................24
10.    Variation Of Rights...................................................24
11.    Confidentiality.......................................................24
12.    Replacement Of Option Certificates....................................25
13.    Notices...............................................................25
14.    Information Rights Of Optionholders...................................25
15.    Effect Of Amended Instrument..........................................25
16.    Third Party Rights....................................................25
17.    Governing Law.........................................................25

SCHEDULE 1           FORM OF OPTION CERTIFICATE..............................27

SCHEDULE 2           REGISTER, TRANSFERS AND NOTICES.........................33

SCHEDULE 3           MEETINGS................................................36

SCHEDULE 4           EXTRAORDINARY RESOLUTION................................40

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THIS AMENDED INSTRUMENT is entered into by way of deed poll on 2 December 2003

BY

ASPEN INSURANCE HOLDINGS LIMITED (formerly Exali Reinsurance Holdings Limited) a
company incorporated in Bermuda (registered number EC32164), whose registered
office is at Cannon's Court, 22 Victoria Street, Hamilton, HM12, Bermuda (the
"COMPANY").

INTRODUCTION:

The Company has, by resolutions of its board of directors passed on 28 May 2002
and 21 June 2002, determined to create and issue options to subscribe for
non-voting ordinary shares in the capital of the Company on the terms and
subject to the conditions set out in the Instrument Constituting an Option to
Subscribe for Shares in Exali Reinsurance Holdings Limited dated 21 June 2002
(the "ORIGINAL INSTRUMENT").

The Company having obtained the prior sanction of an Extraordinary Resolution,
an executed version of which is attached hereto as Schedule 4, pursuant to
clause 10.1 of the Original Instrument, wishes to amend, supplement and restate
the Original Instrument by way of this deed poll (the "INSTRUMENT") as of the
date hereof.

In connection with a proposed Listing as notified to the Optionholders in the
2003 Listing Notice, the Company has effected an Adjustment Event in accordance
with clause 5.2 whereby the Subscription Rights exercisable in respect of
Options have been increased by a multiple of 10 and the Subscription Price for
each Option Share upon the exercise of such adjusted Subscription Rights has
been reduced by a multiple of 10. In connection with this Instrument, the
Optionholders shall be deemed to have received a notice of the Adjustment Event
with respect to this Adjustment.

THIS INSTRUMENT WITNESSES as follows:

1.     INTERPRETATION

1.1    In this Instrument:

       "2003 LISTING NOTICE"           has the meaning set out in clause 4.4.

       "ACT"                           means the Bermudan Companies Act 1981;

       "ADJUSTMENT EVENT"              has the meaning set out in clause 5.3;

       "ADJUSTMENT"                    has the meaning set out in clause 5.3;

       "AFFILIATE"                     means in relation to any person, any
                                       undertaking which from time to time
                                       Controls, is Controlled by or is under
                                       the same Control as such party;

       "ANTICIPATED COMPLETION DATE"   has the meaning set out in clause 4.4;

       "APPLICABLE CONSENT"            has the meaning set out in clause 4.7;

       "ASSET SALE"                    means a sale by the Company or any of its
                                       subsidiaries for the time being of all or


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                                       substantially all the business, assets or
                                       undertakings of the Group;

       "AUTHORISED OPTIONHOLDERS"      has the meaning set out in clause 5.7;

       "BOARD"                         means the board of directors of the
                                       Company from time to time;

       "BUSINESS DAY"                  means a day other than a Saturday or
                                       Sunday on which banks generally are open
                                       for the transaction of normal banking
                                       business in London or New York, or both,
                                       as the context requires;

       "BYE-LAWS"                      means the bye-laws of the Company at the
                                       date of the Original Instrument and as
                                       amended from time to time;

       "CASH-LESS EXERCISE"            means the exercise of an Option pursuant
                                       to clause 4.9;

       "CLAIM OF WELLINGTON BREACH"    has the meaning set out in clause 4.2;

       "CONTROL"                       means, in relation to an undertaking, the
                                       ability for the time being, whether
                                       directly or indirectly, to control:

                                       (i)   50% or more of the voting rights
                                             exercisable at general meetings of
                                             the members of that undertaking on
                                             all, or substantially all, matters;

                                       (ii)  the right to appoint or remove
                                             directors having 50% or more of the
                                             voting rights exercisable at
                                             meetings of the board of directors
                                             of that undertaking on all, or
                                             substantially all, matters;

                                       (iii) all, or substantially all business
                                             decisions of that undertaking; and

                                       (iv)  any undertaking which is controlled
                                             by another undertaking shall be
                                             deemed to be controlled by further
                                             undertakings which control the
                                             controlling undertaking;

                                       and "Controls" and other cognate
                                       expressions shall be construed
                                       accordingly;

       "DOLLAR RATE"                   has the meaning set out in clause 4.9;


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       "EVENT NOTICE"                  has the meaning set out in clause 4.4;

       "EXIT EVENT"                    means a Sale, an Asset Sale or a Listing;

       "EXIT VALUE"                    (i) means: on or after a Listing,

                                       (a)   where Options are exercised
                                             pursuant to clause 4.1(ii), the
                                             price per share at which an
                                             Ordinary Share is sold or offered
                                             in connection with the Listing (in
                                             the case of (x) the first
                                             registered public offering of
                                             Ordinary Shares under the United
                                             States securities laws, the initial
                                             offering price to the public, or
                                             (y) an offer for sale, being the
                                             underwritten price or, if an offer
                                             for sale by tender, the striking
                                             price under such offer or, in the
                                             case of a placing, the price at
                                             which a share is sold under the
                                             placing);or

                                       (b)   where Options are exercised
                                             pursuant to clause 4.1(iii), the
                                             higher of the par value of each
                                             Ordinary Share and the average of
                                             the per share Post-Listing Market
                                             Price of the Ordinary Shares for
                                             the five (5) Trading Days
                                             immediately prior to (but not
                                             including) the fifth Trading Day
                                             preceding the date of exercise; or

                                       (c)   in the case of the Names' Option
                                             pursuant to clause 4.1(iv), where
                                             Subscription Rights are exercised
                                             in connection with the First
                                             Underwritten Secondary Offering,
                                             the price per share at which
                                             Ordinary Shares are sold or offered
                                             in connection with the First
                                             Underwritten Secondary Offering;

                                       (d)   in the case of the Names' Option
                                             pursuant to clause 4.1(iv), where
                                             Subscription Rights are exercised
                                             in connection with the Harrington
                                             Trust Demand, the average of the
                                             per share Post-Listing Market Price
                                             of the Ordinary Shares for the five
                                             (5) Trading Days immediately prior
                                             to (but not including) the fifth
                                             Trading Day preceding the date of
                                             exercise;


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                                       (ii)  in the case of a Sale:

                                       (a)   if the Ordinary Shares are being
                                             sold by private treaty (as distinct
                                             from a public offer) and the
                                             consideration per Ordinary Share is
                                             a fixed cash sum payable, such cash
                                             sum per Ordinary Share;

                                       (b)   if the Ordinary Shares are being
                                             sold pursuant to a public cash
                                             offer (or public offer of
                                             securities accompanied by a cash
                                             alternative), the cash
                                             consideration or cash alternative
                                             price per Ordinary Share;

                                       (c)   if the Sale is by private treaty or
                                             public offer and the consideration
                                             is the issue of securities (not
                                             accompanied by a cash alternative):

                                             if the securities rank pari passu
                                             with a class of securities that is
                                             listed on the London Stock Exchange
                                             or publicly traded on a securities
                                             exchange in the United States (in
                                             the case of a private treaty) the
                                             value attributed to such
                                             consideration in the related sale
                                             agreement containing the terms of
                                             such offer, or, in the case of a
                                             sale following a public offer or
                                             failing any such attribution in the
                                             related sale agreement, by
                                             reference to the value of such
                                             consideration determined by
                                             reference to the average middle
                                             market quotation of such securities
                                             over the five trading days in
                                             London or New York (as the case may
                                             be) prior to the day on which the
                                             offer for or intention to acquire
                                             the Ordinary Shares is first
                                             announced by the proposed
                                             purchaser; or

                                             if the securities are not of such a
                                             class, the value of such securities
                                             as determined in good faith by the
                                             Board and as confirmed or adjusted
                                             by the Independent Advisers (if so
                                             required by the Authorised
                                             Optionholders) in accordance with
                                             clause 5.7; and

                                       (iii) in the case of an Asset Sale:


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                                       (a)   the cash sum payable as
                                             consideration on completion of the
                                             acquisition by a purchaser of the
                                             undertakings and assets of the
                                             Group divided by the total number
                                             of Ordinary Shares in issue or
                                             capable of being issued, which will
                                             constitute the fully diluted share
                                             capital of the Company, at the date
                                             of such sale ("ASSET
                                             CONSIDERATION"); or

                                       (b)   if the Asset Consideration is the
                                             issue of securities, the value of
                                             such securities determined in the
                                             same manner as for a Sale;

       "EXPIRATION TIME"               means 3pm London time on the fifth
                                       Business Day following the later of (i)
                                       the last day of the Term and (ii) if
                                       applicable, the last day of the Extended
                                       Term (in each case counting as the first
                                       of such Business Days the first Business
                                       Day after such last day of the Term or
                                       the Extended Term), as the case may be;

       "EXTENDED ANTICIPATED
        COMPLETION DATE"               has the meaning set out in clause 4.4;

       "EXTENDED NOTICE OF EXERCISE"   has the meaning set out in clause 4.6;

       "EXTENSION DATE"                has the meaning set out in clause 4.5;

       "EXTRAORDINARY RESOLUTION"      means a written resolution passed in
                                       accordance with paragraph 17 of Schedule
                                       3 or a resolution passed at a duly
                                       convened meeting of the Optionholders in
                                       accordance with Schedule 3 by
                                       Optionholders holding Options entitling
                                       them to subscribe for not less than 75%
                                       of the total number of Option Shares for
                                       which the Optionholders who vote at such
                                       meeting are entitled to subscribe;

       "FAIR MARKET VALUE"             means the fair market value as determined
                                       in good faith by the Board and as
                                       confirmed or adjusted by the Independent
                                       Advisers (if so required by the
                                       Authorised Optionholders) in accordance
                                       with clause 5.7;

       "FIRST UNDERWRITTEN SECONDARY
        OFFERING"                      means, following a Listing, the first
                                       underwritten secondary offering initiated
                                       by a shareholder party to the
                                       Registration Rights Agreement


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                                       pursuant to its demand registration
                                       rights thereunder;

       "FRAMEWORK AGREEMENT"           means a framework agreement made between
                                       Wellington Underwriting Agencies Limited,
                                       Wellington Underwriting Services Limited,
                                       Wellington, Aspen Services Limited and
                                       the Company, dated 28 May 2002, as may be
                                       amended from time to time;

       "GROUP"                         means the Company and its subsidiaries
                                       from time to time and "MEMBER OF THE
                                       GROUP" shall be construed accordingly;

       "HARRINGTON TRUST DEMAND"       means the right of the Names Trustee
                                       under the Registration Rights Agreement
                                       to request that Aspen register Option
                                       Shares held by the Names Trustee for a
                                       non-underwritten direct resale between
                                       the 240th and the 285th day following the
                                       Company's Listing, in the event that the
                                       First Underwritten Secondary Offering
                                       does not take place prior to the 240th
                                       following the Company's Listing (and
                                       subject to other restrictions set out in
                                       the Registration Rights Agreement);

       "INDEPENDENT ADVISERS"          means, for the purpose of this
                                       Instrument, the independent accountant or
                                       a reputable independent financial
                                       institution agreed and appointed jointly
                                       by the Authorised Optionholders and by
                                       the Board or failing agreement on such
                                       appointment within five Business Days,
                                       the President for the time being of the
                                       Institute of Chartered Accountants in
                                       England and Wales (or his duly appointed
                                       deputy) on the application of either the
                                       Authorised Optionholders or the Board;

       "LISTING"                       means (i) the first admission to trading
                                       on the London Stock Exchange of Ordinary
                                       Shares or any shares for which the
                                       Ordinary Shares have been exchanged or
                                       into which the Ordinary Shares have been
                                       converted or any shares in a company of
                                       which the Company is a subsidiary, (ii)
                                       the first registered public offering of
                                       the Ordinary Shares under the United
                                       States securities laws or (iii) any
                                       amalgamation, scheme of arrangement,
                                       consolidation or other business
                                       combination transaction as a result of
                                       which the


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                                       shareholders of the Company receive as
                                       consideration equity securities of a
                                       class that is admitted to trading on the
                                       London Stock Exchange or publicly traded
                                       on a securities exchange in the United
                                       States;

       "MANAGEMENT INCENTIVE SCHEME"   means the schemes, plans or arrangements
                                       pursuant to which employees and/or
                                       non-employee directors of the Group are
                                       granted and hold either shares or options
                                       to acquire shares in the Company or any
                                       of its subsidiaries as such scheme may be
                                       amended from time to time and any
                                       successor or replacement share purchase
                                       or option schemes from time to time
                                       adopted by the Group for the benefit of
                                       its employees and/or non-employee
                                       directors;

       "MEMORANDUM"                    means the memorandum of association of
                                       the Company on the date of this
                                       Instrument as amended from time to time;

       "NAMES' OPTION"                 means the Option held by the Names
                                       Trustee entitling the Names Trustee to
                                       subscribe for 3,006,760 Non-Voting
                                       Ordinary Shares (subject to adjustment in
                                       accordance with Clause 5);

       "NAMES TRUST"                   means a trust constituted by a
                                       declaration of trust dated on around 28
                                       May 2002 as amended from time to time,
                                       which holds the Names' Option on trust on
                                       behalf of the Names or such other trust
                                       on behalf of the Names as may be
                                       substituted therefore or to which it may
                                       transfer the Names' Option as
                                       contemplated by the Shareholders
                                       Agreement;

       "NAMES TRUSTEE"                 means Names' Trustees Limited, the
                                       initial trustee of the Names Trust, or
                                       Harrington Trust Limited, the successor
                                       trustee of the Names Trust, and any other
                                       trustee of the Names Trust, as
                                       applicable;

       "NAMES"                         means the underwriting members of Lloyd's
                                       who participated in Syndicate 2020 for
                                       the 2002 year of account (or in respect
                                       of those individuals who have died, part
                                       of the 2002 year of account), other than
                                       the Wellington corporate members;

       "NON-VOTING ORDINARY SHARES"    means non-voting ordinary shares of the
                                       Company having the rights set out in the
                                       Bye-Laws and in the event of a
                                       sub-division or


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                                       consolidation or reclassification of such
                                       non-voting ordinary shares, the shares
                                       resulting therefrom;

       "NOTICE OF EXERCISE"            means a notice in the form or
                                       substantially in the form set out in the
                                       first schedule to the Option Certificate;

       "OPTION CERTIFICATE"            means a certificate in the form, or
                                       substantially in the form, set out in
                                       schedule 1;

       "OPTION SHARES"                 means 6,787,880 Non-Voting Ordinary
                                       Shares but upon a Listing such Non-Voting
                                       Ordinary Shares shall automatically
                                       convert into Ordinary Shares, when
                                       issued, on a one-to-one ratio (adjusted
                                       as appropriate under clause 5 or in the
                                       event of a Cash-Less Exercise pursuant to
                                       clause 4.9);

       "OPTIONHOLDER"                  means the person to whom an Option has
                                       been granted or transferred and whose
                                       name is registered in the Register;

       "OPTIONS"                       the Options constituted by this
                                       Instrument to subscribe in cash or,
                                       subject to the requirements of clause
                                       4.9, by Cash-Less Exercise, at the
                                       Subscription Price for Option Shares on
                                       the terms and subject to the conditions
                                       of this Instrument;

       "ORDINARY SHARES"               means the ordinary shares of the Company,
                                       having the rights set out in the
                                       Bye-Laws;

       "ORGANISATIONAL DOCUMENTS"      means the Bye-Laws and the Memorandum;

       "ORIGINAL SHAREHOLDERS
        AGREEMENT"                     means the subscription and shareholders
                                       agreement dated 28 May 2002 made between
                                       (1)the Company, (2) Blackstone F12
                                       Capital Partners (Cayman) L.P. and
                                       others, (3) Paul Myners, (4) Chris O'Kane
                                       and Others and (5) Wellington as amended
                                       on 21 June 2002, 17 September 2002, 03
                                       October 2002, 22 November 2002, 27
                                       November 2002 and 11 February 2003;

       "POST-LISTING  EXERCISE"        has the meaning set out in clause 4.1;

       "POST-LISTING MARKET PRICE"     means, on any particular date, the
                                       closing bid price per Ordinary Share on
                                       such date on the primary securities
                                       exchange or automated quotation system on
                                       which Ordinary Shares are


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                                       then traded;

       "PRIMARY EXCHANGE"              has the meaning set out in clause 4.9;

       "REGISTER"                      means the register of persons entitled to
                                       the benefit of the Options required to be
                                       maintained pursuant to this Instrument;

       "REGISTERED OFFICE"             means the registered office of the
                                       Company from time to time;

       "REGISTRATION RIGHTS AGREEMENT" means the Third Amended and Restated
                                       Registration Rights Agreement, by and
                                       among the Company, BCP Excalibur Holdco
                                       (Cayman) Limited and others, Wellington,
                                       and the Names Trustee, dated as of 14
                                       November 2003, as may be amended,
                                       restated, supplemented or otherwise
                                       modified from time to time;

       "RELEVANT VALUE"                means:

                                       (i)   if the Option is exercised pursuant
                                             to clause 4.1(v), the current book
                                             value of an Ordinary Share
                                             determined in good faith by the
                                             Board and as confirmed or adjusted
                                             by the Independent Advisers (if so
                                             required by the Authorised
                                             Optionholders) in accordance with
                                             clause 5.7; or

                                       (ii)  if the Option is exercised on an
                                             Exit Event or after a Listing, the
                                             Exit Value;

       "REPURCHASE"                    has the meaning set out in clause 9;

       "RETURNS"                       means the amount per Ordinary Share of
                                       any distribution or payment of cash,
                                       marketable securities (valued at the
                                       average of the closing prices for the 5
                                       most recent trading days for such
                                       marketable securities prior to the date
                                       of distribution or payment) or any other
                                       asset or property (valued at Fair Market
                                       Value) made by the Company to any of its
                                       shareholders in their capacity as
                                       shareholders at any time from the date of
                                       the Original Instrument (i.e., 21 June
                                       2002) to the date of issue of an Option
                                       Share, it being acknowledged that, from
                                       21 June 2002 through 2 December 2003,
                                       there have been no returns;

       "REVOCATION NOTICE"             has the meaning set out in clause 4.6;


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       "SALE"                          means the transfer (whether through a
                                       single transaction or a series of
                                       transactions) of 50% or more of the
                                       Ordinary Shares in issue taken together
                                       to a person and its Affiliates or to any
                                       group of persons acting together, other
                                       than (x) prior to a Listing, a transfer
                                       to a Permitted Transferee (as defined in
                                       the Bye-Laws) or (y) on or following a
                                       Listing, a transfer to a Permitted
                                       Transferee (as defined in the
                                       Shareholders Agreement, as applicable);

       "SHARE"                         means an issued share of any class in the
                                       capital of the Company;

       "SHAREHOLDERS AGREEMENT"        means the Original Shareholders Agreement
                                       as further amended by an amended and
                                       restated Shareholders' Agreement dated as
                                       of 30 September 2003 and as may be
                                       amended further from time to time;

       "STERLING RATE"                 has the meaning set out in clause 4.9;

       "STERLING"                      means the lawful currency of the United
                                       Kingdom for the time being;

       "SUBSCRIPTION PRICE"            means the price payable (or notionally
                                       payable in respect of a Cash-Less
                                       Exercise) per Option Share (rounded to
                                       the nearest two decimal places with 0.005
                                       being rounded upwards) upon exercise of
                                       the Options, being(pound)10 together with
                                       interest on such amount at a rate of 5%
                                       per annum calculated rateably on the
                                       basis of a 365 day year from the date of
                                       the Original Instrument (i.e., 21 June
                                       2002) to the date of exercise less any
                                       Returns, as adjusted pursuant to clause
                                       5;

       "SUBSCRIPTION RIGHTS"           means the number of Option Shares in
                                       respect of which an Optionholder may
                                       subscribe pursuant to the exercise of an
                                       Option held by such Optionholder
                                       (adjusted as appropriate under clause 5
                                       or in the event of a Cash-Less Exercise
                                       pursuant to clause 4.9);

       "SYNDICATE 2020"                has the meaning given to it in the
                                       Original Shareholders Agreement or the
                                       Shareholders Agreement, as applicable;

       "TERM"                          means, subject to clause 4.2, a period of
                                       five years from the date of the Original
                                       Instrument


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                                       (i.e., 21 June 2002), save that if a
                                       Listing has occurred within five years
                                       from the date of the Original Instrument
                                       (i.e., by 21 June 2007), the term shall
                                       be automatically extended to a period of
                                       ten years from the date of the Original
                                       Instrument (i.e., until 21 June 2012) and
                                       such period from the date of such a
                                       Listing to the tenth anniversary of the
                                       Original Instrument shall be referred to
                                       as the "EXTENDED Term";

       "TRADING DAY"                   means with respect to the primary
                                       securities exchange or automated
                                       quotation system on which Ordinary Shares
                                       are traded, a day on which such primary
                                       securities exchange or automated
                                       quotation system is open for trading;

       "UNCLEARED FUNDS EXERCISE
        REQUEST"                       has the meaning set forth in clause 4.5;

       "U.S. DOLLAR"                   means the lawful currency of the United
                                       States of America;

       "UPDATED NOTICE EVENT"          has the meaning set out in clause 4.4;

       "WELLINGTON OPTION"             means the Option held by Wellington
                                       entitling Wellington to subscribe for
                                       3,781,120 Non-Voting Ordinary Shares
                                       (subject to adjustment in accordance with
                                       clause 5);

       "WELLINGTON SHAREHOLDER'S
        AGREEMENT"                     means the Shareholder's Agreement between
                                       Wellington and the Company, dated as of 6
                                       November 2003, as amended, restated,
                                       supplemented or otherwise modified from
                                       time to time;

       "WELLINGTON"                    means Wellington Underwriting PLC;

       "WINDOW PERIOD"                 has the meaning set out in clause 4.10;
                                       and


1.2    Words and expressions defined in the Bye-Laws shall, unless otherwise
       defined in this Instrument, have the same meaning when used in this
       Instrument.

1.3    The headings in this Instrument do not affect its interpretation.

1.4    In this Instrument:

       1.4.1  a clause, paragraph or schedule, unless specifically provided
              otherwise, is a reference to a clause or paragraph of, or schedule
              to, this Instrument;


                                      -11-
<PAGE>

       1.4.2  a "PERSON" includes a reference to a corporation, body corporate,
              association or partnership, individual, and to that person's legal
              personal representatives, successors and assigns;

       1.4.3  a statutory provision includes a reference to the statutory
              provision as modified or re-enacted or both from time to time
              before the date of this Instrument and any subordinate legislation
              made or other thing done under the statutory provision before the
              date of this Instrument;

       1.4.4  the singular includes the plural and vice versa (unless the
              context otherwise requires); and

       1.4.5  a company is a "SUBSIDIARY" of another company, its "HOLDING
              COMPANY", if such other company owns either directly or indirectly
              through its subsidiaries shares or stock or other ownership
              interests having a majority of the voting power in electing the
              board of directors thereof or other persons performing a similar
              function.

1.5    The schedules to this Instrument form part of this Instrument and shall
       have the same force and effect as if expressly set out in the body of
       this Instrument.

1.6    An Option is "OUTSTANDING" unless all of the Subscription Rights in
       respect of such Option have been exercised in full or have lapsed in
       accordance with the provisions of this Instrument.

2.     CONSTITUTION AND FORM OF OPTIONS

2.1    The Company hereby creates and issues the Options subject to the
       conditions set out in this Instrument. The Company shall comply with the
       provisions of this Instrument.

3.     REGISTER AND OPTION CERTIFICATES

3.1    The Company shall maintain the Register in accordance with the provisions
       of paragraph 1 of schedule 2.

3.2    Within 7 days following the grant of an Option to an Optionholder, the
       Company shall issue to the Optionholder an Option Certificate setting out
       the total number of Subscription Rights in respect of such Option, and in
       the case of the Wellington Option, the minimum number of Subscription
       Rights that may be exercised at any one time, as recorded in the Option
       Certificate. The Names' Option will not be subject to an exercise of a
       minimum number of Subscription Rights. If an adjustment to such numbers
       of Subscription Rights is required pursuant to clause 5.1 below, the
       Company shall require the Optionholders to return their Option
       Certificates and on receipt of such certificates, new Option Certificates
       shall be delivered to the Optionholders in accordance with the terms of
       clause 5.2.

3.3    Within 7 days following the exercise of an Option in part, the Company
       shall issue to the Optionholder a new Option Certificate setting out the
       remaining Subscription Rights in respect of such Option.


                                      -12-
<PAGE>

4.     SUBSCRIPTION RIGHTS AND MECHANICS OF EXERCISE

4.1    Subject to this clause 4, an Optionholder may, but shall not be obliged
       to, exercise its Option, in whole or in part, at the following times (and
       at no other times):

       (i)    following receipt of an Event Notice in connection with an Exit
              Event which is not a Listing, in accordance with the provisions of
              clauses 4.4, 4.5 and 4.6;

       (ii)   following receipt of an Event Notice in connection with an Exit
              Event which is a Listing, in accordance with the provisions of
              clauses 4.4, 4.5 and 4.6;

       (iii)  if a Listing has occurred within five years from the date of the
              Original Instrument, in respect of any and all remaining
              Subscription Rights which are not exercised contemporaneously on
              the completion of a Listing (a "POST-LISTING EXERCISE"), in
              accordance with the provisions of clause 4.10 applicable to such
              Optionholder;

       (iv)   only with respect to the Names' Option, if a Listing has occurred
              within five years from the date of the Original Instrument, a
              Post-Listing Exercise at the time of the First Underwritten
              Secondary Offering or the Harrington Trust Demand, as applicable,
              in accordance with the provisions of clause 4.10; and

       (v)    if an Exit Event has not occurred on or prior to the last day of
              the Term, on or at any time prior to the Expiration Time, in
              accordance with clause 4.5 (except that the lodging of such Notice
              of Exercise shall be not less than 5 Business Days prior to the
              Expiration Time).

4.2    The Options shall immediately lapse:

       (i)    only with respect to the Wellington Option, in respect of all
              unexercised Subscription Rights thereunder and all exercised
              Subscription Rights thereunder in connection with which Option
              Shares have not been issued, in the event of any material breach
              by Wellington (x) prior to a Listing, of any of its obligations
              under clauses 9.2 or 9.4 of the Original Shareholders Agreement
              which have been notified to Wellington by the Investors and which
              have not been remedied within 30 days of such notification or (y)
              on or following a Listing, under clauses 2.2 or 2.4 of the
              Wellington Shareholder's Agreement or clauses 13 or 15 of the
              Framework Agreement, in each case, which have been notified to
              Wellington by the Company and which have not been remedied within
              30 days of such notification (each, a "CLAIM OF WELLINGTON
              BREACH"), or

       (ii)   in respect of all unexercised Subscription Rights of all
              Optionholders forthwith at the Expiration Time, or

       (iii)  in respect of all unexercised Subscription Rights of all
              Optionholders forthwith on liquidation of the Company (subject to
              compliance with clause 7.1), or

       (iv)   at such time when all Subscription Rights have been exercised and
              no further Options are outstanding; or


                                      -13-
<PAGE>

       (v)    in respect of all unexercised Subscription Rights which are not
              exercised in connection with an Asset Sale or a Sale.

4.3    Pending resolution of a Claim of Wellington Breach, any:

       (i)    Option Shares in respect of unexercised Subscription Rights under
              the Wellington Option; and

       (ii)   Option Shares in respect of all exercised Subscription Rights
              under the Wellington Option which have not been issued,

        shall not be capable of being issued unless and until such Claim of
        Wellington Breach has been resolved in accordance with clause 4.2(i).

4.4    The Company shall give at least 30 Business Days prior written notice of
       the proposed date of completion of an Exit Event (the "EVENT NOTICE"),
       specifying the anticipated date of completion of such Exit Event (the
       "ANTICIPATED COMPLETION DATE"), together with details of the number of
       Subscription Rights each Optionholder is entitled to exercise and the
       aggregate Subscription Price payable in respect thereof. If the Company
       is unable under certain circumstances to give the Event Notice at least
       30 Business Days prior to the Anticipated Completion Date of the relevant
       Exit Event, then the Company will use its best efforts to provide an
       Event Notice as soon as practicable. The content of any Event Notice
       shall be subject to all applicable laws and regulations, including
       applicable laws and regulations relating to the use and dissemination of
       material, non-public information. If the completion date of an Exit Event
       does not occur within 30 days after the Anticipated Completion Date, the
       Company shall give the Optionholders an updated Event Notice (the
       "UPDATED EVENT NOTICE") specifying the new anticipated date of completion
       of such Exit Event (the "EXTENDED ANTICIPATED COMPLETION DATE") and shall
       give a further Updated Event Notice if the completion date does not occur
       within 30 days of the latter date.

       The Optionholders acknowledge that an Event Notice has already been
       provided to them in connection with a proposed Listing (the "2003 LISTING
       NOTICE") and the 2003 Listing Notice shall be deemed effective
       notwithstanding that a Listing may occur prior to the 30th Business Day
       after the date of the 2003 Listing Notice.

4.5    If an Option has become exercisable in accordance with clause 4.1 (except
       for clauses 4.1(iii) and (iv)), the relevant Optionholder may exercise
       its Option, in whole or in part (though, if in part, for the Wellington
       Option, subject to the minimum number of Subscription Rights exercisable
       thereunder as set forth in the Option Certificate issued to Wellington,
       as adjusted in accordance with clause 5 below) by lodging its Option
       Certificate and a duly completed Notice of Exercise at the Registered
       Office (and in respect of an exercise, (x) following receipt of an Event
       Notice or Updated Event Notice pursuant to clause 4.1(i) or (ii), not
       less than 10 Business Days before the Anticipated Completion Date or the
       Extended Anticipated Completion Date, as applicable (but in relation to
       the Names' Option, such later time as the Company in its discretion may
       agree with the Names Trustee but in any event no later than 5 Business
       Days prior to the actual completion date) or, (y) pursuant to clause
       4.1(v) not less than 5 Business Days prior to the Expiration Time) and
       save in relation to a Cash-Less Exercise, together with


                                      -14-
<PAGE>

       remittance in cleared funds for the aggregate Subscription Price payable
       for the Option Shares in respect of which the Subscription Rights are
       being exercised.

       Notwithstanding the above, only with respect to the exercise of the Name
       Options by the Names Trustee pursuant to clause 4.1(ii), the Names
       Trustee may deliver the Notice of Exercise for the number of Subscription
       Rights to be exercised on a cash basis notwithstanding that a specified
       portion of the funds provided to the Names Trustee have not been cleared
       at the time of lodging the Notice of Exercise (the "UNCLEARED FUNDS
       EXERCISE REQUEST"), so long as the Names Trustee shall certify to the
       Company that a cheque, money order or other instrument representing funds
       for the payment of the Subscription Price for such Option Shares has been
       received by the Names Trustee from the beneficiaries of the Names Trust
       before or at the time of the Notice of Exercise, and such certificate
       shall specify the portion of the Subscription Rights which constitute the
       Uncleared Funds Exercise Request. In such instance, the Names Trustee
       shall have 5 Business Days after the actual completion date (the
       "EXTENSION DATE") to deliver the cleared funds to the Company in an
       amount equal to the Uncleared Funds Exercise Request provided that in
       respect of the Uncleared Funds Exercise Request the Names Trustee shall
       only deliver cleared funds to the Company on or prior to the Extension
       Date in respect of payment of the Subscription Price for any Option
       Shares to the extent that the Names Trustee has received cleared funds
       from the relevant beneficiary on whose behalf the Names Trustee would
       hold such Option Shares. In any event, the Company shall issue Option
       Shares only to the extent that funds for the payment of the Subscription
       Price for Option Shares to which the Uncleared Funds Exercise Request
       relate have been received by the Company in cleared funds on or prior to
       the Extension Date. The Names Trustee shall notify the Company on the
       Extension Date of the amount of funds referred to in its Uncleared Funds
       Exercise Request which have not been cleared on or prior to the Extension
       Date, and the Notice of Exercise of the Names Trustee shall be deemed not
       to have been exercised validly to the extent that funds for the payment
       of the Subscription Price have not been received by the Company by the
       Extension Date.

4.6    A Notice of Exercise lodged in connection with an Event Notice or Updated
       Event Notice in accordance with clause 4.5 shall be irrevocable (except
       with the Board's consent) save only that subject to the provisions of
       this clause 4.6, (i) a Notice of Exercise shall be deemed to be
       conditional upon completion of the Exit Event occurring within no more
       than 90 days after the date of the Event Notice or Updated Event Notice,
       as the case maybe, and if the Exit Event does not occur within this
       period, or (ii) if the Company has determined that the Exit Event has
       been terminated, the Notice of Exercise will be deemed revoked. In such
       event:

       4.6.1  the Company shall forthwith give written notice to each
              Optionholder of such revocation (the "REVOCATION NOTICE");

       4.6.2  the Company shall deliver to each Optionholder, together with the
              Revocation Notice, any Option Certificate delivered pursuant to
              clause 4.5 and any banker's draft for the same amount as any
              banker's draft delivered pursuant to clause 4.5; and


                                      -15-
<PAGE>

       4.6.3  the Subscription Rights that were remaining immediately prior to
              delivery of the Notice of Exercise in respect of then outstanding
              Options shall be reinstated.

       Notwithstanding the foregoing provisions of this clause 4.6, in respect
       of any Notice of Exercise lodged in connection with an Exit Event, the
       Company may, no less than 10 Business Days prior to the expiration of 90
       days after the related Event Notice or Updated Event Notice, as the case
       may be (unless such Exit Event has been terminated), by written notice to
       the Optionholder who lodged such Notice of Exercise, extend the
       effectiveness of such Notice of Exercise for an additional 90 days (the
       "EXTENDED NOTICE OF EXERCISE") at the end of which such Extended Notice
       of Exercise will be deemed revoked if the related Exit Event has not
       occurred and the terms of clauses 4.6.1 to 4.6.3 shall apply, provided
       that, at any time after the expiration of 90 days from the related Event
       Notice, the Optionholder who lodged such Notice of Exercise may revoke,
       in whole or in part, such Notice of Exercise, by 10 Business Days'
       written notice to the Company, provided further that, if such Exit Event
       occurs during such 10 Business Day period in which the Optionholder has
       revoked its Notice of Exercise, such revocation shall not be effective.

4.7    The Company shall following receipt of a Notice of Exercise apply for any
       applicable consent for the issue of the Option Shares from the Bermudan
       Monetary Authority or any successor body (the "APPLICABLE CONSENT") on
       behalf of the Optionholders and procure that, subject to the provisions
       of the Organisational Documents and to compliance with any applicable
       law, regulatory requirement, judgement, order or decree, any Option
       Shares to be issued upon the exercise of an Option shall be allotted and
       issued to the relevant Optionholders or as they may direct together with
       share certificates in respect thereof and that such persons are entered
       in the register of members of the Company as the holders of the Option
       Shares allotted and issued to them, no later than 7 days thereafter
       subject to receipt of the Applicable Consent.

4.8    Option Shares issued pursuant to clause 4.7:

       4.8.1  shall be credited as fully paid;

       4.8.2  shall have the rights and be subject to the restrictions set out
              in the Bye-Laws and the Original Shareholders Agreement or
              Shareholders Agreement, as applicable, relating to Non-Voting
              Ordinary Shares prior to a Listing, and Ordinary Shares after a
              Listing, and will be issued with such restrictive legends as are
              required under the Bye-Laws and/or the Original Shareholders
              Agreement or the Shareholders Agreement, as applicable; and

       4.8.3  shall be entitled to receive any dividend or other distribution
              which has previously been announced or declared (but not yet
              paid), provided that the date by which the holder of Non-Voting
              Ordinary Shares prior to a Listing, or Ordinary Shares after a
              Listing, must be registered to participate in such dividend or
              other distribution is on or after the date on which the Notice of
              Exercise in respect of such Option Shares was lodged with the
              Company.

4.9    In connection with the valid exercise of an Option pursuant to the
       applicable provisions in this clause 4, each Optionholder may elect to
       have all or part of its Subscription Rights


                                      -16-
<PAGE>

       exercised as a Cash-Less Exercise and if the Company has sufficient share
       premium account out of which to effect a bonus issue of the said number
       of its Option Shares to be issued (as calculated below) to enable the
       relevant number of Option Shares to be allotted fully-paid, then the
       number of Option Shares to be issued as a Cash-Less Exercise shall be
       calculated as:

       Number of Option Shares to be issued on a Cash-Less basis = A x (C-B)/C

       Where A = the number of Option Shares which would be issued on a cash
       payment basis in respect of the Subscription Rights requested to be
       exercised on a Cash-Less basis

       B = Subscription Price (on a cash payment basis); and

       C = the Relevant Value of an Option Share;

       provided, however, if the foregoing calculation results in a negative
       number, then no Option Shares shall be issued.

       If the primary securities exchange on which the Ordinary Shares are
       traded at the time of a Cash-Less Exercise (other than if pursuant to
       clause 4.1(i) the Relevant Value thereof is denominated in a currency
       other than U.S. Dollars) is in the United States of America (the "PRIMARY
       EXCHANGE"), the Subscription Price for purposes of this clause 4.9 will
       be converted from Sterling into U.S. Dollars at the average spot rate of
       exchange as quoted by the New York branch of Citibank N.A. at 11:00 AM
       (New York time) for the five New York Business Days prior to the fifth
       Business Day preceding the exercise date (the "DOLLAR RATE"). In the case
       of any exercise pursuant to clause 4.1(i) in which the Relevant Value is
       denominated in a currency other than U.S. Dollars but the Primary
       Exchange is in the United States, the Relevant Value (if not denominated
       in Sterling) for purposes of this clause 4.9 shall be converted into
       Sterling at the average spot rate of exchange as quoted by the London
       branch of Citibank N.A. at 11:00 AM (London time) for the five London
       Business Days prior to the fifth Business Day preceding the exercise date
       (the "STERLING RATE"). If the Primary Exchange is not in the United
       States or there has been no prior Listing, then the Relevant Value (if
       not denominated in Sterling) for purposes of this clause 4.9 will be
       converted into Sterling at the Sterling Rate in the case of any Cash-Less
       Exercise (other than an exercise pursuant to Clause 4.1(v), in which case
       the Subscription Price shall be converted into US Dollars at the Dollar
       Rate). The product of the currency calculations in this paragraph shall
       be rounded to the nearest two decimal places with 0.005 being rounded
       upwards.

       In calculating the number of Option Shares to be issued pursuant to this
       clause 4.9, fractions shall be rounded down to the nearest whole Option
       Share.

4.10   If an Option has become exercisable in accordance with clause 4.1(iii),
       the relevant Optionholder may exercise its Option in whole or in part by
       (i) lodging its Option Certificate and a duly completed Notice of
       Exercise at the Registered Office as soon as practicable but no later
       than 10 Business Days, in the case of the Names' Option, and 8 Trading
       Days, in the case of the Wellington Option, prior to the requested
       exercise date (which exercise date shall be no later than the Expiration
       Time) and (ii) save in relation to a Cash-Less Exercise, together with
       remittance in cleared funds for the aggregate


                                      -17-
<PAGE>

       Subscription Price payable for the Option Shares in respect of which such
       Option is being exercised. Once lodged a Notice of Exercise shall be
       irrevocable.

       The Names' Option that is exercisable in accordance with clause 4.1 (iii)
       may be exercised in whole or in part no more than once per calendar year,
       but in any event prior to the Expiration Time, pursuant to a 45-day
       window period prior to or during which the Names Trustee will send a form
       of election to the Names to elect whether they wish to exercise into
       Ordinary Shares at the Subscription Price or as a Cash-Less Exercise (the
       "WINDOW PERIOD"). The Window Period shall commence in each calendar year
       beginning in 2005 on the next Business Day following the day on which the
       Company has published or released its annual report and accounts in such
       year (and the Company shall promptly notify the Names Trustee of any such
       date of publication and promptly, on request, provide to the Names
       Trustee sufficient copies of any such publication for distribution to the
       beneficiaries of the Names Trust), provided that if the Company does not
       publish or release its annual report and account by 30 June in any
       calendar year, the Window Period shall commence on such later date as the
       Names Trustee shall determine and accordingly shall notify the Company at
       least 5 Business Days prior to such date. At the end of the Window
       Period, the Names Trustee will lodge the Notice of Exercise and remit any
       applicable funds for payment of the Subscription Price as described in
       the preceding paragraph.

       The Wellington Option that is exercisable in accordance with clause
       4.1(iii) may be exercised at any time (i.e. Wellington is not limited to
       an annual exercise window period) in whole or in part (subject to the
       minimum number of Subscription Rights exercisable thereunder as set forth
       in the Option Certificate issued to Wellington, as adjusted in accordance
       with clause 5 below), but in any event prior to the Expiration Time.
       Notwithstanding the irrevocability of a Notice of Exercise once lodged,
       in the event that, after Wellington having lodged its Notice of Exercise
       with respect to the Wellington Option, a calamity or crisis shall have
       occurred that causes a suspension in trading in securities generally on
       the Primary Exchange or a suspension in trading in the Ordinary Shares on
       the Primary Exchange during the period in which the Exit Value is
       calculated in accordance with clause 4.9, then upon the request of
       Wellington, such Notice of Exercise shall be revoked.

       If the Names' Option has become exercisable in accordance with Clause
       4.1(iv), then the Names Trustee may exercise the Names' Option in whole
       or in part by (i) lodging its Option Certificate and a duly completed
       irrevocable Notice of Exercise and (ii) save in relation to a Cash-Less
       Exercise, together with remittance of cleared funds for the aggregate
       Subscription Price payable for the Option Shares, no later than 5
       Business Days prior to the completion of the First Underwritten Secondary
       Offering or the date of effectiveness of the registration statement in
       connection with the Harrington Trust Demand, as the case may be.

5.     ADJUSTMENT AND ANTI-DILUTION

5.1    Save where it has obtained the prior sanction of an Extraordinary
       Resolution, the Company shall not, whilst any Options are outstanding,
       create any further Options under this Instrument or supplemental thereto.


                                      -18-
<PAGE>

5.2    Save where it has obtained the prior sanction of an Extraordinary
       Resolution, if the Company whilst any Options are outstanding, effects
       any:

       5.2.1  allotment or issue of any Shares (whether for cash, by way of
              capitalisation of profits or reserves (including share premium
              account and any capital redemption reserve fund) or for non-cash
              consideration or otherwise howsoever) other than:

              (a)    the issue of Shares to the Optionholders; or

              (b)    the issue of Shares to employees under the Management
                     Incentive Scheme;

       5.2.2  grant, or permits the grant of, any options, warrants or other
              rights to subscribe for, or calls for, the allotment or issue of
              any Shares other than pursuant to this Instrument or the
              Management Incentive Scheme;

       5.2.3  allotment or issue of any securities convertible or exchangeable
              into Shares of the Company;

       5.2.4  sub-division or consolidation or reclassification of Shares;

       5.2.5  issue of any loan stock or similar debt instruments to holders of
              Shares or to any Affiliate of any holder of Shares;

       5.2.6  issue, grant or distribution or takes any other action if its
              effect would be that on the exercise of any of the Subscription
              Rights it would be required to issue Option Shares at a discount;
              or

       5.2.7  a sale or other disposal of all or a substantial part of the
              business, assets, or undertaking to any shareholder in the Company
              or to any holding company of a shareholder in the Company or to
              any subsidiary of such holding company,

       which is in any case below or deemed to be below Fair Market Value or is
       a sub-division, consolidation or reclassification of Shares then it shall
       adjust the Subscription Rights (including any applicable minimum number
       of Subscription Rights that may be exercised) and/or the Subscription
       Price so as to maintain the real value of the Subscription Rights as
       nearly as possible at the same level as prior to such action both by
       taking into account any dilution of the Subscription Rights and any
       change in the value of the Company as a whole created by such action, but
       so that in the event of any capitalisation of profits or reserves the
       aggregate Subscription Price shall not be increased and in any event the
       Subscription Price shall not be less than the par value of (i) the
       Non-Voting Ordinary Shares prior to a Listing, or (ii) the Ordinary
       Shares after a Listing.

5.3    The Company shall send to each of the Optionholders as soon as reasonably
       practicable after any of the actions set out in clauses 5.2.1 to 5.2.7
       (inclusive) (an "ADJUSTMENT EVENT") has occurred any adjustments to the
       Subscription Rights and the Subscription Price in accordance with clause
       5.2 (an "ADJUSTMENT") together with a notice setting out the details of
       the Adjustment Event and the Adjustments made, and a replacement


                                      -19-
<PAGE>

       Option Certificate, evidencing each Optionholder's adjusted Subscription
       Rights. If the Optionholders are not satisfied with the decision of the
       Board and any adjustment to be made, then they may on the authorisation
       of an Extraordinary Resolution provided such notification is made within
       40 Business Days following any notification made by the Board regarding
       any Adjustment Event (whether or not any Adjustments have been made by
       the Board) refer the matter to the Independent Advisers in accordance
       with clause 5.4.

5.4

       (a)    If so requested by the Optionholders in accordance with clause
              5.3, the Independent Advisers shall deliver to the Optionholders
              and the Company within 30 days a certificate setting out in their
              reasonable opinion the effect of any Adjustment Event on the value
              of the Subscription Rights and the Adjustments which in their
              opinion are fair and reasonable in all the circumstances. Such
              adjustments shall include insofar as appropriate, any adjustments
              required pursuant to the proviso to clause 5.2.

       (b)    The Company shall issue within 7 days such substituted and/or
              additional Options (if any) and/or any adjustment to the
              Subscription Price as the Independent Advisers shall certify as
              expert in their reasonable opinion shall be necessary to reflect
              the adjustments contemplated by the Independent Advisers'
              certificate delivered to the Optionholders in accordance with
              paragraph (a) above to the extent that these adjustments vary from
              the Adjustments proposed by the Board.

       (c)    The costs incurred by the Independent Advisers under this
              paragraph (c) shall be for the account of the Company unless the
              conclusions of the Independent Advisers appointed under this
              paragraph (c) as to any adjustments which in their opinion are
              necessary are the same in all material respects as the conclusions
              of the Board set out in the Adjustment referred to in clause 5.3
              above, in which case such costs shall be for the account of the
              Optionholders.

       (d)    The provisos in paragraphs (a), (b) and (c) above do not apply to
              the negative covenants in clauses 5.2.4 (to the extent necessary
              to preserve the minimum share premium for the purposes set out in
              clause 6.1(e)) (save where the Company has requested and obtained
              the prior consent of the Optionholders by Extraordinary
              Resolution).

       (e)    In the event that the Subscription Rights and/or the Subscription
              Price are adjusted pursuant to this clause 5.4, the Optionholders
              shall deliver their Option Certificates to the Company, on the
              condition that the Company undertakes on receipt to issue new
              Option Certificates reflecting such adjustments.

       (f)    The decision of the Independent Advisers is, in the absence of
              fraud or manifest error, final and binding on the parties.

5.5    In calculating any adjustments to the Subscription Rights pursuant to
       clause 5.2, fractions shall be rounded down to the nearest whole Option
       Share.


                                      -20-
<PAGE>

5.6    Except in connection with an Exit Event, in case the Company after the
       date hereof shall:

       (i)    consolidate or amalgamate with or into any other person and shall
              not be the continuing corporation of such consolidation or
              amalgamation;

       (ii)   permit any other person to consolidate or amalgamate with or into
              the Company and the Company shall be the continuing person but, in
              connection with such consolidation or amalgamation, the Non-Voting
              Ordinary Shares shall be changed into or exchanged for stock or
              other securities of any other person or cash or any other
              property;

       (iii)  enter into a scheme of arrangement with any other person;

       (iv)   effect a capital reorganisation or reclassification of the
              Non-Voting Ordinary Shares (other than a capital reorganisation or
              reclassification resulting in an adjustment to the Subscription
              Price and Subscription Rights as provided in clause 5.2); or

       (v)    effect any other transaction in which the Non-Voting Ordinary
              Shares are changed into or exchanged for stock or other securities
              of any other person, in each case, except in respect of a Listing,

       then, provision shall be made so that, upon the basis and the terms and
       in the manner provided in this Instrument, upon the exercise by an
       Optionholder of all remaining Subscription Rights in respect of its
       Option at any time after the consummation of such transaction, such
       Optionholder shall immediately exercise all remaining Subscription Rights
       and shall be entitled to receive (at the aggregate Subscription Price in
       effect at the time of such consummation for all Non-Voting Ordinary
       Shares issuable upon such exercise immediately prior to such
       consummation), in lieu of the Non-Voting Ordinary Shares issuable upon
       such exercise prior to such consummation, the amount of securities, cash
       or other property to which such Optionholder would actually have been
       entitled as a holder of Non-Voting Ordinary Shares upon such consummation
       if such Optionholder had exercised all such remaining Subscription Rights
       immediately prior thereto. Adjustments for events subsequent to the
       consummation of such a consolidation, amalgamation, scheme of
       arrangement, or sale of assets shall be as nearly equivalent as may be
       practicable to the adjustments provided for in this Instrument. In any
       such event, effective provisions will be included in the certificate or
       articles of incorporation of the resulting or surviving corporation, in
       any contract of sale, conveyance, transfer or otherwise so that the
       provisions set forth herein for the protection of the rights of the
       Optionholders shall thereafter continue to be applicable, and any such
       resulting or surviving corporation or transferee shall expressly assume
       the obligation to deliver, upon exercise, such securities, cash and
       property. The provisions of this clause shall similarly apply to
       successive consolidations, amalgamations, and schemes of arrangement or
       sales.

5.7    Subject to clause 5.8, if the Optionholders, on the authorisation of an
       Extraordinary Resolution ("AUTHORISED Optionholders") are not satisfied
       with the determination of the Board, as to the Exit Value (except for the
       Exit Value in connection with a Listing), the Relevant Value or the Fair
       Market Value (as appropriate) then the Authorised Optionholders may
       require the Independent Advisers to review the Board's determination


                                      -21-
<PAGE>

       and to deliver an opinion by delivering a certificate to the
       Optionholders and the Company, and the Company shall irrevocably agree to
       make such adjustments (if any) to the Exit Value, the Fair Market Value
       or the Relevant Value (as applicable) prior to an Exit Event or
       Repurchase as the Independent Advisers shall certify in their reasonable
       opinion, to be necessary. For the purpose of any Sale or Asset Sale to
       Wellington or one of its Affiliates, notwithstanding the other provisions
       of this Instrument, such adjustment may take into account as part of the
       Exit Value determined any collateral benefits arising from related
       transactions which they consider should properly be regarded as forming
       part of the consideration of the relevant Sale or Asset Sale. The
       provisions regarding costs in clause 5.4(c) shall apply mutatis mutandis
       to this clause.

5.8    If an Extraordinary Resolution is put to Optionholders in accordance with
       clause 5.7 in circumstances where a sale confers benefits principally
       upon Wellington or one of its Affiliates, then in these circumstances
       none of Wellington or any of its Affiliates shall be entitled to vote on
       any resolution passed to authorise such appointment.

6.     UNDERTAKINGS OF THE COMPANY

6.1    Subject to clause 6.2, the Company represents and warrants to the
       Optionholders and undertakes to procure that whilst any Options are
       outstanding (except with the prior sanction of an Extraordinary
       Resolution) it will:

       (a)    keep available for issue sufficient authorised but unissued share
              capital free from pre-emptive rights to satisfy in full the
              exercise of all outstanding Options;

       (b)    forthwith upon becoming aware of any offer being made or required
              to be made (i) prior to a Listing, under Bye-law 41 (Tag-along
              rights) in effect prior to a Listing or (ii) on or following a
              Listing, under Section 3 of the Shareholders Agreement (Tag-along
              rights) in effect upon a Listing, give notice of the offer to all
              Optionholders and shall use all reasonable endeavours to ensure
              that an equal offer is made to the Optionholders as if they had
              exercised their Subscription Rights, but adjusted to deduct the
              Subscription Price;

       (c)    ensure that the Board at all times has all power and authority
              (or, before a Listing, call all meetings of shareholders of Aspen
              to seek all requisite consents and authorities) necessary to give
              effect to any bonus issue of (i) Non-Voting Ordinary Shares prior
              to a Listing or (ii) Ordinary Shares, on or following a Listing,
              for the Cash Less Exercise required by clause 4.9;

       (d)    ensure that the Company maintains at all times prior to the
              exercise of the last Option sufficient share premium account to
              allot the (i) Non-Voting Ordinary Shares prior to a Listing or
              (ii) Ordinary Shares, on or following a Listing, to the
              Optionholders as required by clause 4.9;

       (e)    not reduce the share capital of the Company, any share premium
              account (except upon a Cash-Less Exercise) or capital redemption
              reserve fund or otherwise repay, redeem or repurchase capital of
              the Company; and

       (f)    not alter the Bye-Laws or modify any of the rights attaching to
              any Shares of the Company in such a way which could reasonably be
              expected to have,


                                      -22-
<PAGE>

              whether at the relevant time or after that, a non de minimis
              adverse effect on the value of the Subscription Rights or on the
              timing of their exercise.

6.2    The Company will not require the prior sanction of an Extraordinary
       Resolution to undertake any of the actions contemplated by clauses 6.1(e)
       and 6.1(f) inclusive if it has first obtained an opinion from the
       Independent Advisers that:

       6.2.1  such actions would not be materially prejudicial to the
              Optionholders taken as a whole in a manner which would not affect
              all holders of Shares in the same manner and for these purposes
              holders of Shares shall include holders of Options; or

       6.2.2  such actions have created an Adjustment Event.

6.3    The Company will not purchase, and will procure that its subsidiaries
       will not purchase, Options unless an offer to purchase is made pro rata
       to all Optionholders based on, for any given Optionholder, the ratio that
       the number of remaining Subscription Rights held by such Optionholder
       bears to the total number of remaining Subscription Rights held by all
       Optionholders, save that this clause shall not apply to a purchase made
       by the Company pursuant to clause 9.

7.     WINDING UP OF THE COMPANY

7.1    If at any time while any Options are outstanding an order is made or an
       effective resolution is passed for the winding up or dissolution of the
       Company or if any other dissolution of the Company by operation of law is
       to be effected:

       7.1.1  if the winding up or dissolution is for the purpose of
              implementing a reconstruction, amalgamation or scheme of
              arrangement on terms previously sanctioned by an Extraordinary
              Resolution, such terms shall be binding on the Optionholders; and

       7.1.2  in any other case, the Company shall as soon as reasonably
              practicable send to the Optionholders a written notice stating
              that such an order has been made or resolution has been passed or
              other dissolution is to be effected. An Optionholder may at any
              time within three months after the date of such notice elect, by
              written notice to the Company, to be treated as if he had,
              immediately before the date of the making of the order or passing
              of the resolution or other dissolution, exercised all or part of
              his Subscription Rights. On giving such notice, the Optionholder
              is entitled to receive out of the assets which would otherwise be
              available in the liquidation to the shareholders of the Company,
              such a sum, if any, as he would have received had he been the
              holder of and paid for the Option Shares to which he would have
              become entitled by virtue of that exercise, after deducting from
              that sum an amount equal to the aggregate Subscription Price which
              would have been payable by him upon such exercise. Nothing
              contained in this clause has the effect of requiring an
              Optionholder to make any actual payment to the Company.


                                      -23-
<PAGE>

8.     TRANSFER OF OPTIONS

       The Options are only transferable in accordance with the provisions of
       paragraph 2 of schedule 2. The Company shall issue a replacement Option
       Certificate to each of Wellington and the Names Trustee upon execution of
       this Instrument in the form of Schedule 1.

9.     REPURCHASE

9.1    The Company shall have the right (but not the obligation) to purchase the
       Options held by an Optionholder at the Fair Market Value of the Options
       (the "REPURCHASE"), within 15 Business Days of it becoming aware of the
       occurrence of any of the following events:

       9.1.1  the passing by the Optionholder of a resolution for its winding up
              or the making by a court of competent jurisdiction of an order for
              the winding up of the Optionholder or the dissolution of the
              Optionholder otherwise than, in each case, for the purposes of a
              bona-fide reorganisation;

       9.1.2  the making of an administration order in relation to the
              Optionholder or the appointment of a receiver over, or the taking
              possession of or sale by an encumbrancer of, any of the
              Optionholder's assets or, in relation to the Optionholder
              incorporated outside England and Wales, analogous proceedings
              taking place in the relevant jurisdiction;

       9.1.3  the making by the Optionholder of an arrangement or composition
              with its creditors generally or the making by the Optionholder of
              an application to a court of competent jurisdiction for protection
              from its creditors generally; or

       9.1.4  in respect of an Optionholder who is an individual, that
              individual is adjudged bankrupt, or makes any arrangement or
              composition with his or her creditors.

10.    VARIATION OF RIGHTS

10.1   All or any of the rights for the time being attached to the Options
       (including the Subscription Rights) may from time to time (whether or not
       the Company is being wound up) only be altered or abrogated with the
       prior sanction of an Extraordinary Resolution and shall be effected by an
       instrument by way of deed poll executed by the Company and expressed to
       be supplemental to this Instrument.

10.2   A memorandum of every such supplemental deed as is referred to in clause
       10.1 shall be endorsed on the Option Certificate and notice of such
       alteration or abrogation or modification shall be given by the Company to
       the Optionholders within five Business Days of it occurring.

11.    CONFIDENTIALITY

       The Optionholders shall keep confidential information relating to an Exit
       Event unless such information is required to be disclosed by law, by a
       rule of a securities exchange on which its shares are traded or by a
       governmental authority or other authority with relevant powers to which,
       in each case, the Optionholder is subject or submits, provided that such
       disclosure shall so far as is practicable be made after consultation with
       the


                                      -24-
<PAGE>

       Company and after taking into account, so far as practicable, the
       Company's reasonable requirements as to its timing, content and manner of
       making or despatch.

12.    REPLACEMENT OF OPTION CERTIFICATES

       If an Option Certificate is mutilated, defaced, lost, stolen or destroyed
       it will be replaced by the Company upon payment by the Optionholder of
       the Company's reasonable costs in connection with the issue of the
       replacement and on such terms as to evidence and indemnification as the
       Company may reasonably require. Mutilated or defaced Option Certificates
       in respect of which replacements are being sought must be surrendered
       before replacements will be issued.

13.    NOTICES

       Any notice to be given to or by the Optionholders shall be given in
       accordance with the provisions of paragraph 3 of schedule 2.

14.    INFORMATION RIGHTS OF OPTIONHOLDERS

14.1   The Company shall send to each Optionholder a copy of its Annual Report
       and all documents required by law to be annexed to it and copies of each
       statement, notice or circular issued to the members of the Company
       concurrently with the issue of the Annual Report to its members.

14.2   Optionholders shall be entitled to attend and speak at all meetings of
       the Company's shareholders but shall not be entitled to vote in their
       capacity as Optionholders.

14.3   The Company shall procure that each Optionholder (being the Names Trust
       for the Names who shall be sent such number of copies as it shall
       require) is sent copies of quarterly consolidated group accounts
       comprising a balance sheet, a profit and loss account and cash flow at
       the same time as they are sent to shareholders or, following a Listing,
       quarterly financial statements, if any, published in accordance with
       applicable laws.

15.    EFFECT OF AMENDED INSTRUMENT

       This Amended Instrument amends, supplements and restates the Original
       Instrument. Except as amended and supplemented hereby, the terms of the
       Original Instrument continue and remain in full force and effect and are
       restated herein for convenience.

16.    THIRD PARTY RIGHTS

       A person who is not a party to this Instrument has no right under the
       Contract (Rights of Third Parties) Act 1999 to enforce any term of this
       Instrument but this does not affect any right or remedy of a third party
       which exists or is available apart from that Act (including, without
       limitation, the rights of the Optionholders pursuant to this Instrument).

17.    GOVERNING LAW

17.1   This Instrument and the Options shall be governed by English Law.


                                      -25-
<PAGE>

17.2   The courts of England shall have exclusive jurisdiction to settle any
       dispute arising from or connected with this Instrument or the Options.

IN WITNESS WHEREOF this Instrument has been executed by the Company as a deed
and is intended to be and is hereby delivered on the date first above written.


Executed as a deed by        )
ASPEN INSURANCE              )
HOLDINGS LIMITED             )




/s/ Christopher O'Kane              Signature of Director
-----------------------



CHRISTOPHER O'KANE................  Name of Director



/s/ Julian Cusack                   Signature of Director
-----------------------



JULIAN CUSACK.....................  Name of Director


                                      -26-
<PAGE>


                                   SCHEDULE 1

                           FORM OF OPTION CERTIFICATE


                        ASPEN INSURANCE HOLDINGS LIMITED

                                (THE "COMPANY")

            (Incorporated in Bermuda with registered number EC32164)


                               OPTION CERTIFICATE

Certificate No:..........................


Date of Issue:...........................


Name and Address of Optionholder:


...........................................................                ,


.................................................................................


..................


Number of Subscription Rights:


...........................................................


Minimum Number of Subscription Rights Exercisable: 1,000,000, without regard to
the form of exercise whether in cash or on a Cash-Less basis (or all of the
remaining Subscription Rights if, following a proposed exercise of Subscription
Rights, fewer than the stated minimum would be remaining) *



THIS IS TO CERTIFY that the Optionholder named above is the registered holder of
an Option which entitles the holder (inter alia) to subscribe for the number of
Option Shares in the capital of the Company specified above, in accordance with
and subject to the provisions of the instrument entered into by way of deed poll
constituting Options to subscribe for certain Non-Voting Ordinary Shares in the
capital of the Company dated 21 June 2002, as amended, supplemented and restated
by an amended and restated instrument dated 2 December 2003 (the "INSTRUMENT")
and subject to the Organisational Documents. Terms defined in the Instrument
have the same meaning when used in this Certificate. The Optionholder is
entitled to the benefit of, is bound by, and is deemed to have knowledge of, all
of the provisions of the Instrument. [The Wellington Option shall only be
transferable to a wholly-owned subsidiary of Wellington


--------------------------------------------------------------------------------
* NOT APPLICABLE TO NAMES' OPTION


                                      -27-
<PAGE>

save that the Company acknowledges that Wellington may grant a charge over the
Wellington Option and assign the Wellington Option and that it may assign its
rights arising under this Instrument by way of security provided that, before
the grant of the charge and security assignments, the chargee shall have
executed an undertaking in the form of a deed (in terms reasonably satisfactory
to the Company) for the benefit of the Company and the other parties to the
Registration Rights Agreement and the Shareholders' Agreement that the chargee
(or any other person nominated by the chargee as the person to whom the
Wellington Option, the Options Shares and/or rights under this Instrument are to
be transferred) shall execute a deed of adherence to the Shareholders' Agreement
substantially in the form attached thereto and a written agreement to be bound
by the terms and conditions of the Registration Rights Agreement in the form set
out in a schedule to the undertaking of the chargee referred to above prior to,
or at the time, of being registered as the holder of such Wellington Option or
Option Shares whereupon the chargee (or such person) shall be bound by, and have
the benefit of the Shareholders' Agreement and the Registration Rights
Agreement.]

The Options represented by the Option Certificate are subject to certain
transfer restrictions contained in the Instrument. The Options represented by
the Option Certificate have not been registered under the Securities Act of
1933, as amended (the "Securities Act"), or any United States state securities
laws and may not be transferred, sold or otherwise disposed of unless (i)(a) a
registration statement is in effect under the Securities Act with respect to
such options or the underlying shares once such options are exercised, or (b) an
exemption from the registration requirements under the Securities Act is
available or the Securities Act does not apply (and, in such case, an opinion of
counsel reasonably satisfactory to the Company shall have been delivered to the
Company to such effect), and (ii) if required by law, the transferee is approved
by applicable Bermuda regulatory authorities.

The Option Shares when issued would also contain a similar restrictive legend.


                                      -28-
<PAGE>

Executed as a deed by                     )
ASPEN INSURANCE                           )
HOLDINGS LIMITED                          )


_____________________________________     Signature of Director

......................................     Name of Director


_____________________________________     Signature of Director/Secretary

......................................     Name of Director/Secretary


                                      -29-
<PAGE>

                    FIRST SCHEDULE TO THE OPTION CERTIFICATE
                               NOTICE OF EXERCISE



To:    The Directors

       Aspen Insurance Holdings Limited

       Cannon's Court, 22 Victoria Street, Hamilton, HM12, Bermuda

                                                                          [Date]




We hereby exercise Subscription Rights over ............ of the Option Shares
represented by the enclosed Option Certificate [and enclose a bankers
draft/confirm other method of payment agreed by the Company] for (pound)
[ ], being the aggregate Subscription Price payable in respect thereof/by way
of a Cash-Less Exercise]*.



We direct the Company to allot and issue the Option Shares in the following
numbers to the following allottees:


NUMBER                                                  ALLOTTEE





We request that the share certificate(s) for the Option Shares to be issued by
the Company following receipt of this Notice be sent by registered post to us at
the first address shown above, marked for the attention of [o], or to the agent
lodging the Option Certificate as mentioned below. We agree that the Option
Shares are issued to us subject to the Organisational Documents of the Company
and acknowledge that we are required to sign a deed of adherence to the Original
Shareholders Agreement or the Shareholders Agreement, as applicable, and an
agreement to be bound by the terms of the Registration Rights Agreement prior to
the issue of the Option Shares to us, unless we are already a party thereto.]*


Signed  by                                  )

[                         ]                 )

For and on behalf of [o] Limited            )


........................................     Director/Secretary


--------------------------------------------------------------------------------
* Delete as appropriate for a Cash-Less Exercise


                                      -30-
<PAGE>

Lodged by: (agent to whom share certificate(s) should be sent)




Name of Agent ..................................

Address ........................................

.................................................

.................................................

For the attention of............................



                                      -31-
<PAGE>

                    SECOND SCHEDULE TO THE OPTION CERTIFICATE
                                FORM OF TRANSFER

                      [ON HEADED NOTEPAPER OF OPTIONHOLDER]

To:    The Directors

       Aspen Insurance Holdings Limited

       Cannon's Court, 22 Victoria Street, Hamilton, HM12, Bermuda

                                                                          [Date]

Dear Sirs

INSTRUMENT ENTERED INTO BY WAY OF DEED POLL RELATING TO OPTIONS TO SUBSCRIBE FOR
CERTAIN NON-VOTING ORDINARY SHARES IN THE CAPITAL OF ASPEN INSURANCE HOLDINGS
LIMITED DATED 21 JUNE 2002 AS AMENDED, SUPPLEMENTED AND RESTATED BY AN AMENDED
AND RESTATED INSTRUMENT DATED [ ] 2003 (THE "INSTRUMENT").

We hereby give notice that we have today transferred Options to subscribe for
[ ] Option Shares issued pursuant to the Instrument to [Name of transferee] (the
"TRANSFEREE").

We enclose our Option Certificate for cancellation by you. Please would you
issue a new Option Certificate to the Transferee in respect of the Options so
transferred [and a new Option Certificate to us in respect of the balance of the
Options retained by us].

Yours faithfully



.........................................

for and on behalf of

[NAME OF OPTIONHOLDER]


                                      -32-
<PAGE>

                                   SCHEDULE 2

                         REGISTER, TRANSFERS AND NOTICES

1.     REGISTER

1.1    The Company shall keep the Register together with the statutory books of
       the Company at the Registered Office and shall enter in the Register:

       1.1.1  the names and addresses of the Optionholders;

       1.1.2  the number of Subscription Rights held by each Optionholder; and

       1.1.3  the date on which the name of each Optionholder is entered in the
              Register in respect of the Options registered in his name.

1.2    Any change in the name or address of any Optionholder shall be notified
       as soon as reasonably practicable following such change to the Company,
       following which the Company shall update the Register accordingly. The
       Optionholders or any of them or any person authorised by a Optionholder
       shall be entitled at all reasonable times during office hours upon one
       Business Days notice to inspect the Register and to take copies of or
       extracts from the Register.

1.3    The Company shall be entitled to treat the person whose name is shown in
       the Register as an Optionholder as the absolute owner of an Option and,
       accordingly, shall not be bound (except as ordered by a court of
       competent jurisdiction or as required by law) to recognise any equitable
       or other claim to, or interest in, such Option on the part of any other
       person whether or not it has express or other notice of such claim or
       interest.

1.4    An Optionholder may require its total holdings to be designated in the
       register by one or more entries.

2.     PERMITTED TRANSFERS

2.1    Subject to paragraph 2.2 (in the case of a Wellington Business Entity),
       the Options are only transferable by each Optionholder in whole or in
       part in accordance with the Option Certificate.

2.2    If an Optionholder, being a Wellington Business Entity (as defined in the
       Original Shareholders Agreement or the Shareholders Agreement, as
       applicable), ceases to be a wholly-owned subsidiary of Wellington then it
       shall (immediately prior to such cessation) transfer the Options
       registered in its name to Wellington or another wholly owned subsidiary
       of Wellington.

2.3    Every transfer of an Option shall be made by an instrument of transfer in
       the form set out in the second schedule to the Option Certificate or in
       any other form which may be approved from time to time by the Board.

2.4    The instrument of transfer of an Option shall be signed by or on behalf
       of the transferor but need not be signed by or on behalf of the
       transferee. The transferor shall be deemed


                                      -33-
<PAGE>

      to remain the holder of the Option until the name of the transferee is
       entered in the Register in respect of the Option.

2.5    The Board may decline to recognise any instrument of transfer of an
       Option unless such instrument is deposited at the Registered Office
       accompanied by the Option Certificate to which it relates and such other
       evidence as the Board may reasonably require to show the right of the
       transferor to make the transfer. The Board may waive production of any
       Option Certificate upon production to them of satisfactory evidence of
       the loss or destruction of such instrument together with such indemnity
       as it may reasonably require. Subject to the foregoing provisions of this
       paragraph, the Board may not decline to recognise any instrument of
       transfer and must register the transfer of the Option(s) in accordance
       with this schedule 2.

2.6    The registration of a transfer shall be conclusive evidence of the
       approval by the Board of the transfer.

3.     NOTICES

3.1    Every Optionholder shall register with the Company an address and
       facsimile number to which notices can be sent and if any Optionholder
       fails so to do, notice may be given to the Optionholder by sending the
       same by any of the methods referred to in paragraph 3.2 of this schedule
       to his last known place of business or residence or, if none, by
       exhibiting the same for three Business Days at the Registered Office.

3.2    Notices and other communications to Optionholders and/or to the Company
       shall be in writing and shall be delivered personally, sent by pre-paid
       recorded delivery (or by air mail if overseas), by email or by facsimile.
       In proving service of a notice or other communication sent by facsimile
       it shall be sufficient to prove that the sender's facsimile machine
       received a confirmation of transmission report and that the facsimile
       message was properly addressed.

3.3    A notice or other communication given pursuant to the provisions of
       paragraph 3.2 of this schedule shall be deemed to have been served:

       3.3.1  at the time of delivery (or where such time is outside the normal
              business hours of the recipient, on the opening of the next
              following Business Day), if delivered personally or sent by
              pre-paid recorded delivery to the registered address of the
              Optionholder or the registered office for the time being of the
              Company, as applicable;

       3.3.2  if sent by air mail, two Business Days after posting it; or

       3.3.3  if sent by email on a Business Day between the hours of 9 a.m. and
              5 p.m. (local time at recipient's address), one hour after
              transmission, and if sent at any other time, at 9 a.m. on the next
              succeeding Business Day, unless, in either case, the sender
              receives a return message within three hours after transmission
              indicating that the email has not been delivered to the intended
              recipient (including any message that the intended recipient is
              "out of the office" or otherwise unavailable), unless the sender
              confirms by telephone directly with the intended recipient his or
              her receipt of the email.


                                      -34-
<PAGE>

       3.3.4  when the sender's facsimile machine receives a confirmation of
              transmission report if delivered by facsimile.

3.4    All notices and other communications with respect to Options registered
       in the names of joint registered holders shall be given to whichever of
       such persons is named first in the Register and any notice so given shall
       be sufficient notice to all the joint registered holders of such Options.

3.5    Any person who, whether by operation of law, transfer or other means
       whatsoever, becomes entitled to any Option shall be bound by every notice
       properly given to the person from whom he derives his title to such
       Option.

3.6    When a given number of days notice is required to be given, the day of
       service shall be included but the day upon which such notice will expire
       shall not be included in calculating the number of days. The signature to
       any notice to be given by the Company may be written or printed.


                                      -35-
<PAGE>

                                   SCHEDULE 3

                                    MEETINGS

1.     EXTRAORDINARY RESOLUTIONS BINDING ON OPTIONHOLDERS

       An Extraordinary Resolution shall be binding upon all the Optionholders,
       whether present or not present at the meeting at which the resolution was
       passed so long as notice of such meeting was given to all of the
       Optionholders, and each of the Optionholders shall be bound to give
       effect to the Extraordinary Resolution. The passing of any Extraordinary
       Resolution shall be conclusive evidence that the circumstances of such
       resolution justified the passing of it. Any such resolution may be
       contained in one document or in several documents in like form each
       signed by one or more of the Optionholders.

2.     CALLING OF MEETINGS

       The Company may at any time, and upon a request in writing of
       Optionholders holding Options entitling them to subscribe for not less
       than 25 per cent. of the Option Shares convene a meeting of Optionholders
       (in default of which such Optionholders may convene a meeting
       themselves). Every such meeting shall be held at such reasonably
       convenient and appropriate place in the United Kingdom or overseas as the
       Board may approve (such approval not to be unreasonably withheld or
       delayed).

3.     NOTICE OF MEETINGS

       At least 21 days notice of the meeting shall be given to Optionholders
       provided that if it is so agreed by a majority in number of Optionholders
       having a right to attend and vote at the meeting, a meeting shall be
       deemed to have been duly called notwithstanding that it has been called
       by less than 21 days notice. The notice shall specify the date, time and
       place of the meeting and the terms of the resolutions to be proposed. The
       accidental omission to give notice to, or the non-receipt of any such
       notice by, any of the Optionholders shall not invalidate the proceedings
       at any meeting.

4.     CHAIRMAN

       The Optionholders present at any meeting shall choose one of their number
       to be chairman.

5.     QUORUM

       At any such meeting two or more persons holding Options and/or being
       proxies and being or representing in the aggregate Optionholder(s)
       registered as the holder(s) of Options entitling them to subscribe for
       not less than 25 per cent. of the Option Shares shall form a quorum for
       the transaction of business. No business other than the choosing of a
       chairman shall be transacted at any meeting unless the requisite quorum
       is present at the commencement of the meeting.

                                      -36-

<PAGE>

6.     ABSENCE OF QUORUM

       If, within half an hour after the time appointed for any meeting, a
       quorum is not present, the meeting shall, if convened upon the
       requisition of Optionholders, be dissolved. In any other case, it shall
       stand adjourned for such period, not being less than seven days nor more
       than 28 days, and to such time and place, as may be appointed by the
       chairman. At such adjourned meeting one or more persons present in person
       holding Options and/or being proxies (whatever the number of Options so
       held or represented) shall for all purposes form a quorum and shall have
       the power to pass any resolution (including an Extraordinary Resolution)
       and to decide upon all matters which could properly have been dealt with
       at the meeting from which the adjournment took place had a quorum been
       present at such meeting.

7.     ADJOURNMENTS

       The chairman may with the consent of (and shall if directed by) any
       meeting adjourn the same from time to time and from place to place but no
       business shall be transacted at any adjourned meeting except business
       which might lawfully have been transacted at the meeting from which the
       adjournment took place.

8.     NOTICE OF ADJOURNMENTS

       At least three days notice of any meeting adjourned due to lack of a
       quorum shall be given to Optionholders in the same manner as for an
       original meeting, and such notice shall state the quorum required at such
       adjourned meeting. Subject to that requirement, it shall not be necessary
       to give any notice of an adjourned meeting.

9.     RESOLUTIONS

       Every question submitted to a meeting shall be decided on a poll.

10.    PERSONS ENTITLED TO SPEAK AND VOTE

       The Company (through its representatives and/or legal and/or financial
       advisers) shall be entitled to attend and speak (but not vote) at any
       meeting of Optionholders. No person may attend or vote at any meeting of
       Optionholders or join with others in requesting the convening of such a
       meeting unless he is a Optionholder or the duly appointed proxy of a
       Optionholder.

11.    VOTES

       At any meeting on a poll every Optionholder who is present in person or
       by proxy shall have one vote in respect of each Option Share in respect
       of which he then holds Subscription Rights.

12.    Any person entitled to more than one vote need not use all his votes or
       cast all the votes to which he is entitled in the same way.


                                      -37-
<PAGE>

13.    INSTRUMENT APPOINTING A PROXY

       Each instrument appointing a proxy must be in writing signed by a duly
       authorised officer of the Optionholder and shall be in such form as the
       Board may approve. The instrument of proxy shall, unless the contrary is
       stated in it, be valid for the meeting to which it relates and need not
       be witnessed. A person appointed to act as a proxy need not be a
       Optionholder. The Names Trust may appoint more than one proxy, each
       representing a specified number of Options.

14.    DEPOSIT OF INSTRUMENT APPOINTING A PROXY

       The instrument appointing a proxy and the power of attorney or other
       authority (if any) under which it is signed or a notarially certified or
       office copy of the power or authority shall be deposited at such place or
       places as the Company (or the Optionholders in default of the Company
       convening the meeting) may in the notice of meeting direct (or if no such
       place is specified then at the Company's registered office) not less than
       48 hours before the time appointed for holding the meeting or adjourned
       meeting or the taking of a poll at which the person named in that
       instrument proposes to vote. The instrument of proxy is invalid if not
       deposited in accordance with this paragraph. A vote given in accordance
       with the terms of an instrument appointing a proxy is valid
       notwithstanding the previous revocation of the instrument of proxy or of
       the authority under which the instrument of proxy is given or transfer of
       the Options in respect of which it is given unless previous notice in
       writing of that revocation or transfer has been received at the Company's
       registered office no later than the Business Day prior to the relevant
       meeting. No instrument to appoint a proxy is valid after the expiration
       of 12 months from the date stated in it as the date of its execution.

15.    POWERS OF MEETINGS OF OPTIONHOLDERS

       A meeting of Optionholders shall (without prejudice to any powers
       conferred on any other person by this Instrument) have the following
       powers exercisable by Extraordinary Resolution:

15.1   power to sanction any compromise or arrangement proposed to be made
       between the Company and the Optionholders or any of them;

15.2   power to sanction any proposal by the Company for the modification,
       abrogation, variation or compromise of, or arrangement in respect of, the
       rights of the Optionholders against the Company whether such rights shall
       arise under this Instrument or otherwise;

15.3   power to sanction any proposal by the Company for the exchange or
       substitution for the Options of, or the conversion of the Options into,
       shares, stock, bonds, debentures, debenture stock or other obligations or
       securities of the Company, or any other body corporate formed or to be
       formed;

15.4   power to assent to any modification of the provisions contained in this
       Instrument which shall be proposed by the Company;


                                      -38-
<PAGE>

15.5   power to authorise any person to concur in and execute all such documents
       and do all such acts and things as may be necessary to carry out and give
       effect to any Extraordinary Resolution;

15.6   power to discharge or exonerate any person from any liability in respect
       of any act or omission for which such person may have become responsible
       under this Instrument;

15.7   power to give any authority, direction or sanction which under the
       provisions of this Instrument is required to be given by Extraordinary
       Resolution; and

15.8   power to appoint any person (whether a Optionholder or not) as an agent
       or to a committee or committees to represent the interests of the
       Optionholders and to confer upon such agent or committee any powers or
       discretions which the Optionholders could themselves exercise by
       Extraordinary Resolution.

16.    EXTRAORDINARY RESOLUTIONS BINDING ON OPTIONHOLDERS

       An Extraordinary Resolution shall be binding upon all the Optionholders,
       whether present or not present at the meeting at which the resolution was
       passed, and each of the Optionholders shall be bound to give effect to
       the Extraordinary Resolution. The passing of any Extraordinary Resolution
       shall be conclusive evidence that the circumstances of such resolution
       justified the passing of it.

17.    WRITTEN RESOLUTION

       A resolution in writing signed by Optionholders in respect of Options
       entitling them to subscribe for not less than 75 per cent. of the Option
       Shares who are for the time being entitled to receive notice of meetings
       in accordance with the provisions of this Instrument shall for all
       purposes be as valid and effective as an Extraordinary Resolution passed
       at a meeting duly convened and held in accordance with the provisions of
       this schedule. Any such resolution may be contained in one document or in
       several documents in like form each signed by one or more of the
       Optionholders.

18.    MINUTES OF MEETINGS

       Minutes of all resolutions and proceedings at every meeting of the
       Optionholders shall be made and duly entered in books provided for that
       purpose from time to time by the Company. Minutes signed by the chairman
       of the meeting at which such resolutions were passed or proceedings
       transacted or by the chairman of the next succeeding meeting of the
       Optionholders, shall be conclusive evidence of the matters contained in
       those minutes. Until the contrary is proved, every meeting in respect of
       the proceedings of which minutes have been made and signed in this way
       shall be deemed to have been duly convened and held and all resolutions
       passed or proceedings transacted at the meeting to have been duly passed
       and transacted.


                                      -39-
<PAGE>

                                   SCHEDULE 4

                            EXTRAORDINARY RESOLUTION

                            WRITTEN RESOLUTION OF THE

                                OPTIONHOLDERS OF

                        ASPEN INSURANCE HOLDINGS LIMITED



                                                 (THE "COMPANY")

In accordance with the terms of the Instrument Constituting an Option to
Subscribe for Shares in the Company dated 21 June 2002 (the "Original
Instrument") we, the undersigned, being all of the Optionholders (as defined
therein) HEREBY RESOLVE as follows:

THAT the amendments to the Option Instrument set out in the Amended and Restated
Instrument Constituting Options to Subscribe for Shares in Aspen Insurance
Holdings Limited attached hereto be and hereby are approved (the "Instrument").

THAT for the purposes of Clause 10 of the Option Instrument this written
resolution of the Optionholders shall constitute the prior sanction of an
Extraordinary Resolution.

Capitalised terms used in this resolution and not otherwise defined herein shall
have the meanings ascribed to them in the Instrument.

This resolution may be executed by the parties listed below in several
counterparts (whether original or facsimile counterparts) and upon the execution
of all such counterparts by one or more parties, each such counterpart shall be
deemed to be an original thereof.



This resolution is dated 2 December 2003.





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ON BEHALF OF WELLINGTON UNDERWRITING PLC




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ON BEHALF OF HARRINGTON TRUST LIMITED



                                      -40-