UNDERWRITING AGREEMENT

Exhibit 1.1

2,010,487

ASPEN INSURANCE HOLDINGS LIMITED

Ordinary Shares

UNDERWRITING AGREEMENT

May 13, 2008

Credit Suisse Securities (USA) LLC  

As Representative of the several
Underwriters named in Schedule 2
11 Madison Avenue
New York, NY 10010

Dear Sirs:

1.     Introductory.     The shareholders listed in Schedule 1 hereto (the ‘‘ Selling Shareholders ’’) propose severally to sell an aggregate of 2,010,487 outstanding shares of the ordinary shares, par value $.0015144558 per share (the ‘‘ Ordinary Shares ’’), of Aspen Insurance Holdings Limited, a Bermuda company (the ‘‘ Company ’’). The Selling Shareholders shall sell 2,010,487 Ordinary Shares (the ‘‘ Offered Securities ’’) subject to the terms and conditions set forth herein. The Selling Shareholders hereby agree pursuant to this agreement (the ‘‘ Agreement ’’) with the Company and with the several Underwriters named in Schedule 2 hereto (the ‘‘ Underwriters ’’) as follows:

2.     Representations and Warranties of the Company and the Selling Shareholders .

(a)    The Company represents and warrants to, and agrees with, the several Underwriters that:

(i)    A registration statement (No. 333-148245) relating to the Offered Securities, including a prospectus (the ‘‘ initial registration statement ’’) has been filed with the Securities and Exchange Commission (the ‘‘ Commission ’’) and has been declared effective under the Securities Act of 1933, as amended (the ‘‘ Act ’’) and either (A) is not proposed to be amended or (B) is proposed to be amended by amendment or post-effective amendment. Either (A) an additional registration statement (the ‘‘ additional registration statement ’’) relating to the Offered Securities may have been filed with the Commission pursuant to Rule 462(b) (‘‘ Rule 462(b) ’’) under the Act (if available) and, if so filed, has become effective upon filing pursuant to such Rule and the Offered Securities have been duly registered under the Act pursuant to the initial registration statement and, if applicable, the additional registration statement or (B) such an additional registration statement is proposed to be filed with the Commission pursuant to Rule 462(b) (if available) and will become effective upon filing pursuant to such Rule, and upon such filing, the Offered Securities will all have been duly registered under the Act pursuant to the initial registration statement and such additional registration statement. If the Company does not propose to amend the initial registration statement or if an additional registration statement has been filed and the Company does not propose to amend it, and if any post-effective amendment to either such registration statement has been filed with the Commission prior to the execution and delivery of this Agreement, the most recent amendment (if any) to each such registration statement has been declared effective by the Commission or has become effective upon filing pursuant to Rule 462(c) (‘‘ Rule 462(c) ’’) under the Act or, in the case of the additional registration statement, Rule 462(b). For purposes of this Agreement, ‘‘ Effective Time ’’ with respect to the initial registration statement or, if filed prior to the execution and delivery of this Agreement, the additional registration statement means (A) if the Company has advised the Representative that it does not propose to amend such registration statement, the date and time as of which such registration statement, or the most recent post-effective amendment thereto (if any) filed prior to the

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execution and delivery of this Agreement, was declared effective by the Commission or has become effective upon filing pursuant to Rule 462(c), or (B) if the Company has advised the Representative that it proposes to file an amendment or post-effective amendment to such registration statement, the date and time as of which such registration statement, as amended by such amendment or post-effective amendment, as the case may be, is declared effective by the Commission. If an additional registration statement has not been filed prior to the execution and delivery of this Agreement but the Company has advised the Representative that it proposes to file one, ‘‘ Effective Time ’’ with respect to such additional registration statement means the date and time as of which such registration statement is filed and becomes effective pursuant to Rule 462(b). ‘‘ Effective Date ’’ with respect to the initial registration statement or the additional registration statement (if any) means the date of the Effective Time thereof. The initial registration statement, as amended at its Effective Time, including all material incorporated by reference therein and including all information contained in the additional registration statement (if any) and deemed to be a part of the initial registration statement as of the Effective Time of the additional registration statement (if any) pursuant to the General Instructions of the Form on which it is filed, is hereinafter referred to as the ‘‘ Initial Registration Statement ’’. The additional registration statement (if any), as amended at its Effective Time, including the contents of the initial registration statement incorporated by reference therein, is hereinafter referred to as the ‘‘ Additional Registration Statement ’’.

‘‘ Registration Statement ’’ as of any time means the Initial Registration Statement and any Additional Registration Statement in the form then filed with the Commission, including any amendment thereto, any document incorporated by reference therein and any prospectus deemed or retroactively deemed to be a part thereof that has not been superseded or modified. ‘‘ Registration Statement ’’ without reference to a time means the Registration Statement as of the time of the first contract of sale for the Offered Securities, which time shall be considered the ‘‘effective time’’ of the Registration Statement. For purposes of this definition, information contained in a form of prospectus or prospectus supplement that is deemed retroactively to be a part of the Registration Statement pursuant to Rule 430B shall be considered to be included in the Registration Statement as of the time specified in Rule 430B.

‘‘ Statutory Prospectus ’’ as of any time means the prospectus relating to the Offered Securities included in the Registration Statement immediately prior to that time, including any document incorporated by reference therein and any basic prospectus deemed to be a part thereof that has not been superseded or modified. For purposes of this definition, information contained in a form of prospectus (including a prospectus supplement) that is deemed retroactively to be a part of the Registration Statement pursuant to Rule 430B shall be considered to be included in the Statutory Prospectus as of the actual time that form of prospectus (including a prospectus supplement) is filed with the Commission pursuant to Rule 424(b) (‘‘ Rule 424(b) ’’) under the Act.

‘‘ Prospectus ’’ means the Statutory Prospectus that discloses the public offering price and other final terms of the Offered Securities and otherwise satisfies Section 10(a) of the Act.

‘‘ Issuer Free Writing Prospectus ’’ means any ‘‘issuer free writing prospectus,’’ as defined in Rule 433, relating to the Offered Securities in the form filed or required to be filed with the Commission or, if not required to be filed, in the form retained in the Company’s records pursuant to Rule 433(g).

‘‘ General Use Issuer Free Writing Prospectus ’’ means any Issuer Free Writing Prospectus that is intended for general distribution to prospective investors, as evidenced by its being specified in a schedule to this Agreement.

‘‘ Limited Use Issuer Free Writing Prospectus ’’ means any Issuer Free Writing Prospectus that is not a General Use Issuer Free Writing Prospectus.

‘‘ Applicable Time ’’ means 8:00 A.M. (New York City time) on the day after the date of this Agreement.

(ii)    On the Effective Date of the Initial Registration Statement, the Initial Registration Statement conformed in all material respects to the requirements of the Act and the rules and

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regulations of the Commission (‘‘ Rules and Regulations ’’) and did not include any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein not misleading. On the Effective Date of the Additional Registration Statement (if any), each Registration Statement conformed, or will conform, in all material respects to the requirements of the Act and the Rules and Regulations and did not include, or will not include, any untrue statement of a material fact and did not omit, or will not omit, to state any material fact required to be stated therein or necessary to make the statements therein not misleading. On the date of this Agreement, the Initial Registration Statement and, if the Effective Time of the Additional Registration Statement is prior to the execution and delivery of this Agreement, the Additional Registration Statement each conforms, and at the time of filing of the Prospectus pursuant to Rule 424(b), each Registration Statement and the Prospectus will conform, in all material respects to the requirements of the Act and the Rules and Regulations, and neither of such documents includes, or will include, any untrue statement of a material fact or omits, or will omit, to state any material fact required to be stated therein or necessary to make the statements therein not misleading. The four preceding sentences do not apply to statements in or omissions from a Registration Statement or the Prospectus based upon written information furnished to the Company by any Underwriter through the Representative specifically for use therein, it being understood and agreed that the only such information is that described as such in Section 8(b) hereof.

(iii)    (A) At the time of filing of the Registration Statement, (B) at time of the most recent amendment of the Registration Statement for the purposes of complying with Section 10(a)(3) of the Act (whether such amendment was by post-effective amendment, incorporated report filed pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended (the ‘‘ Exchange Act ’’), or form of prospectus), and (C) at the time the Company or any person acting on its behalf (within the meaning, for this clause only, of Rule 163(c)) made any offer relating to the Offered Securities in reliance on the exemption of Rule 163, the Company was a ‘‘well-known seasoned issuer’’ as defined in Rule 405, including not having been an ‘‘ineligible issuer’’ as defined in Rule 405.

(iv)    As of the Applicable Time, neither (a) the General Use Issuer Free Writing Prospectus(es) issued at or prior to the Applicable Time, the Statutory Prospectus, the information on Schedule 3 hereto, all considered together (collectively, the ‘‘ General Disclosure Package ’’), nor (b) any individual Limited Use Issuer Free Writing Prospectus, when considered together with the General Disclosure Package, included any untrue statement of a material fact or omitted to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from any prospectus included in the Registration Statement or any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representative specifically for use therein, it being understood and agreed that the only such information is that described as such in Section 8(c) hereof.

(v)    Each Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Offered Securities or until any earlier date that the Company notified or notifies the Representative as described in the next sentence, did not, does not and will not include any information that conflicted, conflicts or will conflict with the information then contained in the Registration Statement. If at any time following issuance of an Issuer Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer Free Writing Prospectus conflicted or would conflict with the information then contained in the Registration Statement or included or would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances prevailing at that subsequent time, not misleading, (a) the Company has promptly notified or will promptly notify the Representative and (b) the Company has promptly amended or will promptly amend or supplement such Issuer Free Writing Prospectus to eliminate or correct such conflict, untrue

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statement or omission. The foregoing two sentences do not apply to statements in or omissions from any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representative specifically for use therein, it being understood and agreed that the only such information is that described as such in Section 8(b) hereof.

(vi)    Neither the Company nor any of its subsidiaries has sustained since the date of the latest audited financial statements included or incorporated by reference in the Prospectus any material loss or interference with its business (exclusive of reinsurance treaties and insurance policies covering third-party risks) from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as set forth or contemplated in the Prospectus; and, since the respective dates as of which information is given in any Registration Statement and the Prospectus, there has not been any material adverse change in the capital stock, the capital or surplus or long-term debt of the Company or any of its subsidiaries or any material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, financial position, shareholders’ equity or results of operations of the Company and its subsidiaries, otherwise than as set forth or contemplated in the Prospectus.

(vii)    Neither the Company nor any of Aspen Insurance UK Limited (‘‘ Aspen U.K .’’) nor Aspen Insurance Limited (‘‘ Aspen Bermuda ’’) (together with Aspen U.K., the ‘‘ Designated Subsidiaries ’’) hold title to any real property; all of the leases, subleases and licenses under which the Company or any of its Designated Subsidiaries holds real properties described in the Prospectus are in full force and effect, and neither the Company nor any Designated Subsidiary has any notice of any claim of any sort that has been asserted by anyone adverse to the rights of the Company or any Designated Subsidiary under any of the leases, subleases or licenses mentioned above, or affecting or questioning the rights of the Company or such Designated Subsidiary to the continued possession of the leased, subleased or licensed premises under any such lease or sublease, except where the failure to have such leases in full force and effect or the failure to have any such notice of any such claim would not, individually or in the aggregate, result in a material adverse change in the condition, financial or otherwise, or in the earnings, results of operations, business affairs, shareholders’ equity or business prospects of the Company and its subsidiaries, taken as a whole (a ‘‘ Material Adverse Effect ’’).

(viii)    The Company has been duly incorporated and is validly existing as an exempted company in good standing under the laws of Bermuda, with power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus, and has been duly qualified as a foreign corporation for the transaction of business and is in good standing under the laws of each other jurisdiction in which it owns or leases properties or conducts any business so as to require such qualification, except where the failure to so qualify would not result in a Material Adverse Effect; each of the Designated Subsidiaries has been duly organized or incorporated and is validly existing as a company or corporation in good standing (including, in the case of Aspen Insurance Limited, as an exempted company) under the laws of its jurisdiction of organization or incorporation, with power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus, and has been duly qualified as a foreign company or corporation for the transaction of business and is in good standing under the laws of each other jurisdiction in which it owns or leases properties or conducts any business so as to require such qualification, except where the failure to so qualify would not result in a Material Adverse Effect; and except for Aspen Specialty Insurance Company (‘‘ Aspen U.S .’’), Aspen (UK) Holdings Limited (‘‘ Aspen U.K. Holdings ’’), Aspen Insurance UK Services Limited (‘‘ Aspen U.K. Services ’’), Aspen U.S. Holdings, Inc. (‘‘ Aspen U.S. Holdings ’’), Aspen Specialty Insurance Management Inc. (‘‘ Aspen Specialty ’’), Aspen Insurance U.S. Services Inc. (‘‘ Aspen U.S. Services ’’), AIUK Trustees Limited, Aspen Re America, Inc. (‘‘ Aspen Re America ’’), Aspen Management Agency Limited and Aspen Underwriting Limited (‘‘ Aspen Lloyd’s ’’), none of which, other than Aspen U.K. Holdings, is a ‘‘significant subsidiary’’ of the Company as that term

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is defined in Rule 1-02(w) of Regulation S-X of the Rules and Regulations, the Designated Subsidiaries are the only subsidiaries of the Company.

(ix)    The Company has an authorized capitalization as set forth in the Prospectus, and all of the issued shares of capital stock of the Company, including the Offered Securities, have been duly and validly authorized and issued, are fully paid and non-assessable and conform to the description of share capital contained in the Prospectus; and all of the currently issued and outstanding shares of capital stock of each subsidiary of the Company have been duly and validly authorized and issued, are fully paid and non-assessable and, except as set forth in the Prospectus, are owned directly or indirectly by the Company, free and clear of all liens, encumbrances, equities or claims; the holders of outstanding shares of capital stock of the Company are not entitled to preemptive or other rights which have not been complied with; other than the Offered Securities, there are no outstanding securities convertible into or exchangeable for, or warrants, rights or options to purchase Ordinary Shares from the Company, or obligations of the Company to issue, Ordinary Shares or any other class of capital stock of the Company (except for (V) up to 870,000 Ordinary Shares provided to eligible employees of the Company and its designated subsidiaries under the Employee Share Purchase Plan and 2008 Sharesave Scheme, as approved by shareholders at the annual general meeting held on April 30, 2008, (W) the options to purchase Ordinary Shares issued to the Appleby Trust (Bermuda) Limited, as trustee, which holds the securities for certain members of Syndicate 2020, (X) the options to purchase Ordinary Shares issued pursuant to the Company’s 2003 Share Incentive Plan, (Y) the options to purchase Ordinary Shares issued pursuant to the Company’s 2006 Stock Option Plan for Non-Employee Directors, and (Z) the conversion rights associated with the Company’s 5.625% Perpetual Preferred Income Equity Replacement Securities); except as disclosed in the Prospectus, there are no restrictions on subsequent transfers of the Offered Securities under the laws of Bermuda, as long as the Ordinary Shares are listed on the New York Stock Exchange (the ‘‘ NYSE ’’), and of the United States; and except as disclosed in the Prospectus, no party has the right to require the Company to register securities.

(x)    This Agreement has been duly authorized, executed and delivered by the Company.

(xi)    There are no currency exchange control laws or withholding taxes, in each case of Bermuda or the United Kingdom (or any political subdivision or taxing authority thereof) that would be applicable to the payment of dividends (A) on the Offered Securities by the Company (other than as may apply to residents of Bermuda for Bermuda exchange control purposes) or (B) by any of the Company’s subsidiaries to the Company; the Bermuda Monetary Authority (the ‘‘ BMA ’’) has designated the Company and Aspen Bermuda as non-resident for exchange control purposes and has granted permission for the issue and free transferability of the Offered Securities pursuant to the Registration Statement, as long as the Ordinary Shares are listed on the NYSE, to and among persons who are non-residents of Bermuda for exchange control purposes (including permission for the issue and free transferability of up to 20% of the Offered Securities to and among persons who are residents of Bermuda for exchange control purposes); such permission has not been revoked and is in full force and effect, and the Company has no knowledge of any proceedings planned or threatened for the revocation of such permission; the Company and Aspen Bermuda are ‘‘exempted companies’’ under Bermuda law and have not (V) acquired and do not hold any land for their respective business in Bermuda, other than that held by way of lease or tenancy for terms of not more than 50 years, without the express authorization of the Bermuda Minister of Finance, (W) acquired and do not hold land by way of lease or tenancy for terms of not more than 21 years in order to provide accommodation or recreational facilities for their officers and employees, without the express authority of the Bermuda Minister of Finance, (X) taken mortgages on land in Bermuda to secure an amount in excess of $50,000, without the consent of the Bermuda Minister of Finance, (Y) acquired any bonds or debentures secured by any land in Bermuda, except bonds or debentures issued by the government of Bermuda or a public authority of Bermuda, or (Z) conducted their business in a manner that is prohibited for ‘‘exempted companies’’ under Bermuda law; neither the Company nor Aspen Bermuda has received notification from the BMA or any other Bermuda governmental authority

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of proceedings relating to the modification or revocation of its designation as non-resident for exchange control purposes, its permission to issue and transfer the Ordinary Shares or its status as an ‘‘exempted company’’.

(xii)    The execution, delivery and performance of this Agreement, the compliance by the Company with all of the provisions hereof and the consummation of the transactions contemplated hereby will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, (A) the certificate of incorporation, memorandum of association, articles of association, bye-laws, by-laws or other organizational document, as amended (any such document, a ‘‘ Constitutional Document ’’), as the case may be, of the Company or any of its subsidiaries, (B) any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, or (C) any statute or any order, rule or regulation of any court or governmental agency or body, any stock exchange authority or any other regulatory authority (hereinafter referred to as a ‘‘ Governmental Agency ’’) having jurisdiction over the Company or any of its subsidiaries or any of their properties, except, in the case of clause (C), as would not, individually or in the aggregate, result in a Material Adverse Effect.

(xiii)    No consent, approval, authorization, order, registration or qualification of or with any Governmental Agency (hereinafter referred to as the ‘‘ Governmental Authorizations ’’) is required for the sale of the Offered Securities or the consummation by the Company of the transactions contemplated hereby, except (A) the registration under the Act of the Offered Securities, (B) such Governmental Authorizations as have been duly obtained and are in full force and effect and copies of which have been furnished to the Representative, (C) such Governmental Authorizations as may be required under state securities laws, Blue Sky laws, insurance securities laws or any laws of jurisdictions outside the United States in connection with the purchase and distribution of the Offered Securities by or for the respective accounts of the Underwriters, (D) such consents, approvals or authorizations required by the NYSE in connection with the listing of the Offered Securities, (E) the filing of the Prospectus with the Registrar of Companies in Bermuda in accordance with Bermuda law and (F) such consents, approvals, authorizations, registrations or qualifications as may be required and have been obtained from the BMA.

(xiv)    Neither the Company nor any of the Designated Subsidiaries is (A) in violation of any of its Constitutional Documents or (B) in default in the performance or observance of any obligation, agreement, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement, lease or other agreement, or instrument to which it is a party or by which it or any of its properties may be bound, except, in the case of clause (B), for any such defaults or violations that would not, individually or in the aggregate, result in a Material Adverse Effect or as otherwise waived or consented to by the parties or shareholders to which the Company or the Designated Subsidiaries owes any obligations under such agreements or documents.

(xv)    No stamp or other issuance or transfer taxes or duties and no capital gains, income, withholding or other taxes are payable by or on behalf of any Underwriter to Bermuda or any political subdivision or taxing authority thereof or therein in connection with (A) the sale and delivery of the Offered Securities to or for the respective accounts of the Underwriters or (B) the sale and delivery outside Bermuda by the Underwriters of the Offered Securities to the initial purchasers thereof.

(xvi)    Except as disclosed in the Prospectus, the Company has no knowledge of any threatened or pending downgrading of the rating accorded the debt securities or preferred shares of the Company or the financial strength or claims-paying ability of the Company or any of the Designated Subsidiaries by A.M. Best Company, Inc., Standard & Poor’s Ratings Service, a Division of The McGraw-Hill Companies, Inc. (‘‘ S&P ’’), or Moody’s Investors Services, Inc. (collectively, the ‘‘ Ratings Agencies ’’ and, individually, a ‘‘ Rating Agency ’’), with the exception of

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S&P, which has reviewed and provisionally affirmed the ratings of the Company’s preferred shares, which affirmation is subject to the satisfaction of certain conditions. The Ratings Agencies are the only ‘‘nationally recognized statistical rating organizations,’’ as that term is defined by the Commission for purposes of Rule 463(g)(2) under the Act, which currently rate the debt securities or preferred shares of the Company or the financial strength or claims-paying ability of the Company or any of the Designated Subsidiaries. None of the Ratings Agencies and no other nationally recognized statistical rating organization currently rates any other securities of the Company or any securities of its subsidiaries.

(xvii)    There are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or any of its subsidiaries is the subject which, if determined adversely to the Company or any of its subsidiaries, would, individually or in the aggregate, result in a Material Adverse Effect; and, to the best of the Company’s knowledge, no such proceedings are threatened or contemplated by any Governmental Agency or threatened by others.

(xviii)    The Company is not and, after giving effect to the offering and sale of the Offered Securities, will not be an ‘‘investment company’’ as defined in the Investment Company Act of 1940, as amended.

(xix)    Each of the Designated Subsidiaries and Aspen Specialty is duly licensed as an insurance brokerage company, insurer or reinsurer, as the case may be, under the insurance laws and the rules, regulations and interpretations of the insurance regulatory authorities thereunder (collectively, ‘‘ Insurance Laws ’’) of each jurisdiction in which the conduct of its existing business as described in the Prospectus requires such licensing, except for such jurisdictions in which the failure to be so licensed would not, individually or in the aggregate, result in a Material Adverse Effect; each of the Company, the Designated Subsidiaries and Aspen Specialty has made all required filings under applicable holding company statutes or other Insurance Laws in each jurisdiction where such filings are required, except for such jurisdictions in which the failure to make such filings would not, individually or in the aggregate, result in a Material Adverse Effect; except as described in the Prospectus, each of the Company, the Designated Subsidiaries and Aspen Specialty has all other necessary authorizations, approvals, orders, consents, certificates, licenses, permits, registrations and qualifications of and from all insurance regulatory authorities necessary to conduct their respective existing businesses as described in the Prospectus and all of the foregoing are in full force and effect, except where the failure to have such authorizations, approvals, orders, consents, certificates, permits, registrations or qualifications or their failure to be in full force and effect would not, individually or in the aggregate, result in a Material Adverse Effect; none of the Company, the Designated Subsidiaries or Aspen Specialty has received any notification from any insurance regulatory authority or other governmental authority in the United States, Bermuda, the United Kingdom or elsewhere to the effect that any additional authorization, approval, order, consent, certificate, permit, registration or qualification is needed to be obtained by either the Company, the Designated Subsidiaries or Aspen Specialty to conduct its existing business as described in the Prospectus; and except as otherwise described in the Prospectus, no insurance regulatory authority has issued any order or decree impairing, restricting or prohibiting the payment of dividends by the Company or any of the Designated Subsidiaries.

(xx)    Each of the Company and the Designated Subsidiaries maintains a system of internal accounting controls sufficient to provide reasonable assurance that (A) transactions are executed in accordance with management’s general or specific authorizations; (B) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset accountability; (C) access to assets is permitted only in accordance with management’s general or specific authorization; and (D) assets as recorded are compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences.

(xxi)    Each of the Company and the Designated Subsidiaries has filed all statutory financial returns, reports, documents and other information required to be filed pursuant to the applicable

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Insurance Laws of the United States and the various states thereof, Bermuda, the United Kingdom and each other jurisdiction applicable thereto, except where the failure, individually or in the aggregate, to file such return, report, document or information would not result in a Material Adverse Effect; and each of the Company and the Designated Subsidiaries maintains its books and records in accordance with, and is otherwise in compliance with, the applicable Insurance Laws of the United States and the various states thereof, Bermuda, the United Kingdom and each other jurisdiction applicable thereto, except where the failure to so maintain its books and records or be in compliance would not, individually or in the aggregate, result in a Material Adverse Effect.

(xxii)    (A) Any tax returns required to be filed by the Company or any of its subsidiaries, other than Aspen U.S., Aspen U.K. and Aspen U.K. Services, in any jurisdiction have been accurately prepared and timely filed and any taxes, including any withholding taxes, excise taxes, franchise taxes and similar fees, sales taxes, use taxes, penalties and interest, assessments and fees and other charges due or claimed to be due from such entities have been paid, other than any of those being contested in good faith and for which adequate reserves have been provided or any of those currently payable without penalty or interest and (B) to the Company’s knowledge, any tax returns required to be filed by Aspen U.S., Aspen U.K. and Aspen U.K. Services in any jurisdiction have been accurately prepared and timely filed and any taxes, including any withholding taxes, excise taxes, franchise taxes and similar fees, sales taxes, use taxes, penalties and interest, assessments and fees and other charges due or claimed to be due from Aspen U.S. have been paid, other than any of those being contested in good faith and for which adequate reserves have been provided or any of those currently payable without penalty or interest, in either case (1) except to the extent that the failure to so file or pay would not result in a Material Adverse Effect and (2) other than those tax returns that would be required to be filed or taxes that would be payable by the Company or any of its subsidiaries if (a) any of them was characterized as a ‘‘personal holding company’’ as defined in Section 542 of the Internal Revenue Code of 1986, as amended (the ‘‘ Code ’’), (b) any of them other than Aspen Specialty, Aspen U.S., Aspen U.S. Holdings, Aspen U.S. Services and Aspen Re America (collectively, the ‘‘ U.S. Subsidiaries ’’) was characterized as engaged in a U.S. trade or business, and (c) any of them other than Aspen U.K., Aspen U.K. Holdings and Aspen U.K. Services (collectively, the ‘‘ U.K. Subsidiaries ’’) was characterized as resident, managed and controlled or carrying on a trade through a branch or agency in the United Kingdom; no deficiency assessment with respect to a proposed adjustment of the Company’s or any of its subsidiaries’ taxes is pending or, to the best of the Company’s knowledge, threatened; and there is no tax lien, whether imposed by any federal, state, or other taxing authority, outstanding against the assets, properties or business of the Company or any of its subsidiaries, in either case, which would have a Material Adverse Effect.

(xxiii)    Each of the Company and Aspen Bermuda have received from the Bermuda Minister of Finance an assurance under the Exempted Undertakings Tax Protection Act 1966, as amended, of Bermuda to the effect set forth in the Prospectus under the caption ‘‘Material Tax Considerations — Taxation of Aspen Holdings and Subsidiaries — Bermuda,’’ and the Company has not received any notification to the effect (and is not otherwise aware) that such assurance may be revoked or otherwise not honored by the Bermuda government.

(xxiv)    Based upon and subject to the assumptions and qualifications set forth in the Prospectus under the caption ‘‘Material Tax Considerations,’’ the Company does not believe (A) that either the Company or any of its subsidiaries currently should be, or upon the sale of the Offered Securities contemplated hereby should be, (1) treated as a ‘‘passive foreign investment company’’ as defined in Section 1297(a) of the Code, (2) characterized as a ‘‘personal holding company’’ as defined in Section 542 of the Code, (3) except for the U.S. Subsidiaries, considered to be engaged in a trade or business within the United States for purposes of Section 864(b) of the Code (although the Internal Revenue Service may be able to successfully assert that Aspen U.K. has a U.S. trade or business and a U.S. permanent establishment as a result of the binding authorities previously granted to Aspen Re America, Aspen Specialty, Aspen Re America

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California, LLC, and Aspen Specialty Insurance Solutions LLC by Aspen U.K. and likely will be able to successfully assert that Aspen U.K. has a U.S. trade or business and a permanent establishment as a result of the binding authorities granted to Aspen Re America by Aspen U.K.), or (4) except for the U.K. Subsidiaries, characterized as resident, managed or controlled or carrying on a trade through a branch or agency in the United Kingdom or (B) that any U.S. person who owns shares of capital of the Company directly or indirectly through foreign entities should be treated as owning (directly, indirectly through foreign entities or by attribution pursuant to Section 958(b) of the Code) 10% or more of the total voting power of the Company or any of its foreign subsidiaries; and to the best of the Company’s knowledge, in the event that the Internal Revenue Service were to be successful in asserting that Aspen U.K. has a U.S. trade or business as a result of the binding authorities previously granted to Aspen Re America, Aspen Specialty, Aspen Re America California, LLC, and Aspen Specialty Insurance Solutions LLC by Aspen U.K., it would not result in a Material Adverse Effect.

(xxv)    Aspen U.K. and Aspen Bermuda intend to operate in a manner that is intended to ensure that the ‘‘related person insurance income’’ (as defined in Section 953(c)(2) of the Code) of either of Aspen U.K. or Aspen Bermuda does not equal or exceed 20% of each such company’s gross insurance income for any taxable year in the foreseeable future.

(xxvi)    The audited consolidated financial statements included or incorporated by reference in the Registration Statement and the Prospectus, together with the related schedules and notes, present fairly, in all material respects, the financial position of the Company and its consolidated subsidiaries at the dates indicated and the statement of operations, shareholders’ equity and cash flows of the Company and its consolidated subsidiaries for the periods specified; except as otherwise disclosed in the Registration Statement and Prospectus, said consolidated financial statements have been prepared in conformity with generally accepted accounting principles in the United States (‘‘ U.S. GAAP ’’) applied on a consistent basis throughout the periods involved; the supporting schedules included or incorporated by reference in the Registration Statement present fairly, in all material respects, in accordance with U.S. GAAP, the information required to be stated therein; and the selected financial data and the summary financial information included or incorporated by reference in the Registration Statement and Prospectus present fairly, in all material respects, the information shown therein and have been compiled on a basis consistent with that of the audited financial statements included or incorporated by reference in the Registration Statement.

(xxvii)    KPMG Audit plc, who has certified certain financial statements of the Company and its subsidiaries, is an independent public accountant as required by the Act and the Rules and Regulations.

The Company is subject to the reporting requirements of either Section 13 or Section 15(d) of the Exchange Act and files reports with the Commission on the Electronic Data Gathering, Analysis, and Retrieval (EDGAR) system. Any documents filed with or furnished to the Commission under the Exchange Act, when they were or are filed with or furnished to the Commission, (A) conformed or will conform in all material respects to the applicable requirements of the Exchange Act and the applicable rules and regulations of the Commission thereunder and (B) did not or will not, as of their respective dates, contain an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading;

(xxviii)     The Company and, to the knowledge of the Company, the Company’s directors and officers, in their capacities as such, are in compliance with the currently applicable provisions of the Sarbanes-Oxley Act of 2002.

(xxix)    The Ordinary Shares have been registered pursuant to Section 12 of the Exchange Act and the outstanding Ordinary Shares, including the Offered Securities, have been listed on the NYSE. The Company has taken no action designed to, or likely to have the effect of, terminating the registration of the Ordinary Shares under the Exchange Act or delisting the

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Ordinary Shares from the NYSE, nor has the Company received any notification that the Commission or the NYSE is contemplating terminating such registration or listing.

(xxxi) No action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency is pending or, to the knowledge of the Company, threatened.

(b)    Each Selling Shareholder, severally and not jointly, represents and warrants to, and agrees with the several Underwriters and the Company as to itself and not as to any other Selling Shareholder that:

(i)    This Agreement has been duly authorized, executed and delivered by or on behalf of such Selling Shareholder;

(ii)    Neither such Selling Shareholder nor any person acting on behalf of such Selling Shareholder (other than, if applicable, the Company and the Underwriters) has used or referred to any ‘‘free writing prospectus’’ (as defined in Rule 405), relating to the Ordinary Shares;

(iii)    Such Selling Shareholder has, or the general partner of such Selling Shareholder, as applicable, has, one or more or all of the general partners of such Selling Shareholder, as the case may be, has, and immediately prior to any Closing Date (as defined in Section 3(e) herein) on which such Selling Shareholder is selling Offered Securities, such Selling Stockholder will have, good and valid title to, or a valid ‘‘security entitlement’’ within the meaning of Section 8-501 of the Uniform Commercial Code the (‘‘ UCC ’’) in respect of, the Ordinary Shares to be sold by such Selling Shareholder hereunder on such Delivery Date, free and clear of all liens, encumbrances, equities or claims.

(iv)    On or about the date hereof, the custody agreement (each, a ‘‘ Custody Agreement ’’ and, together with the custody agreements of each other Selling Shareholder, the ‘‘ Custody Agreements ’’) and, on the date hereof, the power of attorney (a ‘‘ Power of Attorney ’’) of such Selling Shareholder have been duly authorized, executed and delivered by such Selling Shareholder and constitute valid and legally binding obligations of each such Selling Shareholder enforceable in accordance with their terms, except as to rights to indemnification thereunder, which may be limited by public policy, and subject to bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of