General Development of Business

ACE Limited (ACE) is a Bermuda-based holding company incorporated with limited liability under the Cayman Islands Companies Law. ACE and its direct and indirect subsidiaries (collectively, the ACE Group of Companies, the Company, we, us or our) are a global property and casualty insurance and reinsurance organization, servicing the insurance needs of commercial and individual customers in more than 140 countries and jurisdictions.

During the third quarter of 2006, we completed the sale of three of our run-off reinsurance subsidiaries—ACE American Reinsurance Company, Brandywine Reinsurance Co. (UK) Ltd. and Brandywine Reinsurance Company S.A.-N.V. to Randall & Quilter Investment Holdings Limited (R & Q), an international insurance firm. Refer to Note 3 to our Consolidated Financial Statements, under Item 8.

During the second quarter of 2004, we completed the sale of 65.3 percent of our financial and mortgage guaranty reinsurance and insurance businesses through the initial public offering (IPO) of 49 million common shares of Assured Guaranty Ltd. (Assured Guaranty). Pursuant to the completion of the IPO, we received proceeds, net of offering costs, of approximately $835 million and a return of capital of $200 million from Assured Guaranty, which were used to support our P&C business and strengthen our balance sheet capital position. During the fourth quarter of 2006, Assured Guaranty bought back 5.7 million of its own shares from us for proceeds of approximately $150 million. Also during the fourth quarter of 2006, we sold a further 1.2 million Assured Guaranty shares to Banc of America Securities LLC. These transactions reduced our ownership of Assured Guaranty to approximately 28 percent of outstanding shares.

Employees

At December 31, 2006, there were approximately 10,000 employees in the ACE Group of Companies. We believe that employee relations are satisfactory.

Customers

For most of the commercial lines of business that we offer, insureds typically use the services of an insurance broker. An insurance broker acts as an agent for the insureds, offering advice on the types and amount of insurance to purchase and also assisting in the negotiation of price and terms and conditions. We obtain business from all of the major international insurance brokers and typically pay a commission to brokers for any business accepted and bound. Loss of all or a substantial portion of the business provided by one or more of these brokers could have a material adverse effect on our business. In our opinion, no material part of our business is dependent upon a single insured or group of insureds. We do not believe that the loss of any one insured would have a material adverse effect on our financial condition or results of operations and no one insured or group of affiliated insureds account for as much as ten percent of our consolidated revenues.

Competition

Competition in the domestic and international insurance and reinsurance marketplace is substantial. Competition varies by type of business and geographic area. We compete for business not only on the basis of price, but also on the basis of availability of coverage desired by customers and quality of service. Our ability to compete is dependent on a number of factors, particularly our ability to maintain the appropriate financial strength ratings as assigned by independent rating agencies. Our strong capital position and global platform affords us opportunities for growth not available to smaller insurance companies. Competitive information by segment is included in each of the segment discussions.

Trademarks and Trade Names

We use various trademarks and trade names in our business. These trademarks and trade names protect names of certain of the products and services we offer and are important to the extent they provide goodwill and name recognition in the insurance industry. We use commercially reasonable efforts to protect these proprietary rights, including various trade secret and trademark laws. One or more of the trademarks and trade names could be material to our ability to sell our products and services. We have taken appropriate steps to protect our ownership of key names and

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we believe it is unlikely that anyone would be able to prevent us from using names in places or circumstances material to our operations.

Web Site Information

We make available free of charge through our Internet site (www.acelimited.com, under Investor Information / Financial Reports or Investor Information / SEC – Section 16 Filings) our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13 (a) or 15 (d) of the Exchange Act (15 U.S.C. 78m (a) or 78o(d)) as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC.

We also make available free of charge through our Internet site (under Investor Information / Corporate Governance) our Corporate Governance Guidelines, our Code of Conduct and Charters for our Board Committees. These documents are also available in print to any shareholder who requests them from our Investor Relations Department by:

Telephone: (441) 299-9283

Facsimile: (441) 292-8675

E-mail: investorrelations@ace.bm

Nothing on our Internet site should be considered incorporated by reference into this report.

Segment Information

We operate through the following business segments:

• Insurance – North American;

• Insurance – Overseas General;

• Global Reinsurance; and

• Life Insurance and Reinsurance.

Prior to the fourth quarter of 2006 we presented a Financial Services segment; however, since this segment no longer represents a significant part of our operations, we no longer report it separately. We classify the financial solutions business of ACE Financial Solutions and ACE Financial Solutions International (previously included in the Financial Services segment) with the Insurance – North American segment. The financial results of our financial guaranty business through April 28, 2004 (the date of the Assured Guaranty IPO) and our share of the earnings of Assured Guaranty were previously included in the Financial Services segment and have been classified into our corporate results. These segment changes were based primarily on the manner in which we manage the business and accountability for results. All prior periods presented have been amended to conform to this new presentation.

The following table sets forth an analysis of net premiums earned by segment for the years ended December 31, 2006, 2005 and 2004. Additional financial information about our segments, including revenues by geographic area, is included in Note 5 to the Consolidated Financial Statements, under Item 8.

Insurance – North American

Background

The Insurance – North American segment comprises our P&C operations in the U.S., Canada and Bermuda. This segment includes the operations of ACE USA (including ACE Canada), ACE Westchester Specialty, ACE Bermuda and various run-off operations.

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ACE USA, our retail business, operates through several insurance companies using a network of offices throughout the U.S. and Canada. These operations provide a broad range of P&C insurance and reinsurance products to a diverse group of commercial and non-commercial enterprises and consumers.

ACE Westchester Specialty focuses on the wholesale distribution of excess, surplus and specialty P&C products, as well as the retail and wholesale distribution of specialty inland marine products. ACE Bermuda, the original company of the ACE Group of Companies, provides commercial insurance products on an excess basis to a global client base, covering risks that are generally low in frequency and high in severity.

As part of the 1999 acquisition of the P&C business of CIGNA, we acquired Brandywine Holdings Corporation (Brandywine) and its various subsidiaries. The run-off operations include Brandywine, Commercial Insurance Services (CIS), residual market workers’ compensation business, pools and syndicates not attributable to a single business group, and other exited lines of business. Run-off operations do not actively sell insurance products, but are responsible for the management of existing policies and related claims. During the third quarter of 2006, we completed the sale of three of our run-off reinsurance subsidiaries.

As previously discussed, during the fourth quarter of 2006, we began to classify the financial solutions business of ACE Financial Solutions and ACE Financial Solutions International, which was previously presented as part of the Financial Services segment, as part of the Insurance – North American segment. Due to the nature of financial solutions business, premium volume can vary significantly from period to period and therefore premiums written in any one period are not indicative of premiums to be written in future periods. Financial solutions products which do not meet established criteria for insurance or reinsurance accounting under GAAP are recorded using the deposit method of accounting.

Products and Distribution

ACE USA primarily distributes its insurance products through a limited number of retail and wholesale brokers. In addition to using brokers, certain products are also distributed through channels such as general agents, independent agents, managing general agents, managing general underwriters and direct marketing operations. These products include general liability, excess liability, property, workers’ compensation, commercial marine, automobile liability, professional lines (D&O and E&O), medical liability, aerospace, accident and health (A&H) coverages as well as claims and risk management products and services. ACE USA has also established Internet distribution channels for some of its products.

ACE USA’s on-going operations are organized into distinct business units, each offering specialized products and services targeted at specific niche markets.

• ACE Risk Management (ARM) offers custom coverage solutions for large companies and national accounts, irrespective of industry sector. These programs are designed to help large insureds effectively handle the significant costs of financing and managing risk. Products offered include workers’ compensation, general and auto liability coverage and stand-alone excess workers’ compensation catastrophe protection. In addition, ARM offers flexible alternative risk-taking financing structures. ACE Financial Solutions, a division of ARM, provides non-traditional insurance and risk financing solutions for companies with unique risk financing needs.

• ACE Professional Risk (Professional Risk) offers management and professional liability products and surety coverage through a variety of distribution channels, including brokers, agents and direct marketing.

• ACE Canada (ACE USA’s Canadian operations) offers a broad range of P&C products as well as Life and A&H coverage. ACE Canada specializes in providing customized P&C and A&H products to commercial and industrial clients as well as to groups and associations, operating nationally or internationally.

• ACE Medical Risk offers a wide range of liability products for clients throughout the healthcare industry. These include professional liability and general liability for selected types of medical facilities, products liability for biotechnology and pharmaceutical companies and liability insurance for human clinical trials.

• ACE Global Underwriting provides worldwide risk protection by offering global programs and specialty coverages for a broad range of small to large-sized U.S.-based companies. The group’s key products include commercial property, commercial marine, aerospace and foreign casualty lines. ACE Global Underwriting also offers products to meet the insurance needs of North American domiciled energy companies which may have worldwide exposures by providing onshore property, construction and excess casualty coverages as well as offshore property coverage. In addition, this group also provides specialty personal lines coverage for recreational marine, which is distributed through a network of specialty agents.

• ACE Accident & Health works with employers, travel agencies and affinity groups to offer a variety of personal accident, health and travel insurance coverage to their employees, customers and group members. ACE Accident & Health

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also provides specialty personal lines products, including credit card enhancement programs and disaster mortgage protection distributed through alliances and affinity groups.

• ACE Casualty Risk offers a variety of commercial casualty products. This operation provides excess and umbrella liability coverages. ACE Casualty Risk also provides a range of environmental liability insurance products for commercial and industrial risks. ACE Casualty Risk also offers wrap-up programs, which protect contractors and project sponsors with multi-risk coverage on large single- and multi-location construction projects. Small businesses can purchase workers’ compensation coverage through this unit’s Internet-based ACE Complete ^sm product.

• ESIS Inc. (ESIS), ACE USA’s in-house third-party claims administrator, performs claims management and risk control services for organizations that self-insure P&C exposures. These services include comprehensive medical managed care, integrated disability services and pre-loss control and risk management services. Additional insurance-related services are offered by ESIS’s Recovery Services International, which provides salvage and subrogation and health care recovery services.

ACE Westchester Specialty specializes in the wholesale distribution of property, inland marine, and casualty products. ACE Westchester Specialty also provides coverage for agriculture business and specialty programs through its Program division, writing a variety of commercial coverages through program agents, including sports/leisure activities, farm and crop/hail insurance.

ACE Bermuda targets low-frequency, high-severity business on an excess of loss basis. Its principal lines of business are excess liability, professional lines, excess property and political risk, the latter being written on a subscription basis by Sovereign Risk Insurance Ltd. (Sovereign), a wholly owned managing agent. ACE Bermuda also includes ACE Financial Solutions International, offering structured products and loss portfolio transfers. ACE Bermuda accesses its clients primarily through the Bermuda offices of major, internationally recognized insurance brokers.

Underwriting

Operating in a market in which capacity and price adequacy for products can change dramatically, the underwriting strategy for ACE USA and ACE Westchester Specialty is to employ consistent, disciplined pricing and risk selection in order to maintain a profitable book of business. Our priority is to ensure adherence to criteria for risk selection by maintaining high levels of experience and expertise in our underwriting staff. In addition, we have established a business review structure that ensures control of risk quality and conservative use of policy limits, terms and conditions. We also employ sophisticated catastrophe loss and risk modeling techniques to ensure that risks are well distributed and that loss potentials are contained within our financial capacity. In this regard, ACE USA and ACE Westchester Specialty also purchase reinsurance, which provides the means for greater diversification of risk and serves to further limit the net loss potential of catastrophes and large or unusually hazardous risks.

ACE USA and ACE Westchester Specialty have the ability to write business on an admitted basis using forms and rates as filed with state insurance regulators and on a non-admitted, or surplus lines basis, using flexible forms and rates not filed with state insurance regulators. Having access to non-admitted carriers provides the pricing flexibility needed to write non-standard coverage.

An integral part of our operating strategy is to maximize the efficiency and effectiveness of our operations while reducing operating costs. As part of this strategy, ACE USA and ACE Westchester Specialty continue to invest in technology.

ACE Bermuda and its subsidiaries emphasize quality of underwriting rather than volume of business to obtain a suitable spread of risk. All policy applications (both for renewals and new policies) to ACE Bermuda are subject to underwriting and acceptance by underwriters in its Bermuda, Dublin and London offices. A substantial number of policyholders meet with ACE Bermuda outside of the U.S. each year to discuss their insurance coverage.

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Competitive Environment

Traditionally, the markets in which ACE USA and ACE Westchester Specialty compete are subject to significant cycles of fluctuating capacity and wide disparities in price adequacy. We strive to offer superior service, which we believe has differentiated us from our competitors. The ACE USA and ACE Westchester Specialty operations pursue a specialist strategy and focus on market opportunities where we can compete effectively based on service levels and product design, while still achieving an adequate level of profitability. ACE USA and ACE Westchester Specialty offer experienced claims-handling, loss control and risk management staff with proven expertise in specialty fields, including large and midsize-risk P&C, recreational and ocean marine, primary and excess casualty, inland marine, aviation, professional risk and workers’ compensation. A competitive advantage is also achieved through ACE USA’s innovative product offerings and our ability to provide multiple products or many products to a single client due to our national presence allowing us to provide them on a local basis. An additional competitive strength of all our domestic commercial units is the ability to deliver global products and coverage to customers in concert with our Overseas General segment. ACE USA has grown, in part, from the leveraging of cross-marketing opportunities with our other operations to take advantage of our organization’s global presence.

Insurance – Overseas General

Background

The Insurance – Overseas General segment consists of ACE International, which comprises our network of indigenous retail insurance operations, and the wholesale insurance operations of ACE Global Markets, our London market underwriting unit including Lloyd’s Syndicate 2488. This segment has four regions of operations: the ACE European Group which is comprised of ACE Europe and ACE Global Markets branded business, ACE Asia Pacific, ACE Far East and ACE Latin America. The ACE European Group represented approximately 65 percent of this segment’s net premiums written in 2006. The Insurance – Overseas General segment writes a variety of insurance products including, but not limited to, property, casualty, professional lines (D&O and E&O), marine, energy, aviation, political risk, consumer-oriented products and A&H (principally accident and supplemental health).

ACE International comprises our international operations, providing insurance coverage on a worldwide basis. ACE Global Markets comprises our international wholesale insurance operations located within ACE European Group Limited (AEGL) and at Lloyd’s via Syndicate 2488. ACE provides funds at Lloyd’s to support underwriting by Syndicate 2488, which is managed by ACE Underwriting Agencies Limited and has an underwriting capacity of £400 million in 2007. AEGL, our London-based, FSA-U.K. regulated company, underwrites U.K. and Continental Europe insurance and reinsurance business. At December 31, 2006, AEGL held cross-border permissions in 27 European Economic Area countries and branch establishments in 16 European countries, and was also eligible to underwrite excess and surplus (E&S) business in 41 U.S. states.

In line with the increasing acceptance of AEGL as an alternative London-based ACE operation, we have continued to write a greater proportion of ACE Global Markets’ business through AEGL. Syndicate 2488 will continue to retain a diverse book of business, with an emphasis on specialty lines most suited to Lloyd’s.

Products and Distribution

ACE International maintains a presence in every major insurance market in the world. Its P&C business is generally written, on both a direct and assumed basis, through major international, regional and local brokers. A&H and other consumer lines products are distributed through brokers, agents, direct marketing programs and sponsor relationships.

ACE International’s P&C operations are organized geographically along product lines that provide dedicated underwriting focus to customers. Its international organization offers capacity and technical expertise in underwriting and servicing clients from large and complex risks to general market customer segments as well as individual coverages in selected markets for medium to large clients. Property insurance products include traditional commercial fire coverage as well as energy industry-related and other technical coverages. Principal casualty products are commercial primary and excess casualty and general liability. ACE International provides D&O and professional indemnity coverages. Marine cargo and hull coverages are written in the London market as well as in marine markets throughout the world. The A&H insurance operations provide products that are designed to meet the insurance needs of individuals and groups outside of U.S. insurance markets. A&H products have been representing an increasing portion of ACE International’s business in recent years and include, but are not limited to, accidental death, medical, and hospital

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indemnity and income protection coverages. ACE International’s personal lines operations provides specialty products and services designed to meet the needs of specific target markets and include, but are not limited to, property damage, auto, homeowners and personal liability.

Following is a discussion of Insurance – Overseas General’s four regions of operations: ACE European Group, ACE Asia Pacific, ACE Far East and ACE Latin America.

• ACE European Group is headquartered in London and offers a broad range of P&C and specialty coverages principally directed at large and mid-sized corporations, as well as individual consumers. ACE European Group operates in every major market in the European Union. Commercial products are principally distributed through brokers while consumer products (mainly A&H) are distributed through brokers as well as through direct marketing programs. ACE European Group also has operations in Central and Eastern Europe, the Commonwealth of Independent States (the CIS), and the Middle East and North Africa. Central and Eastern Europe and the CIS markets are serviced through our Warsaw and Moscow offices which were opened in 2005. The Middle East and North Africa region includes insurance subsidiaries and joint ventures in Egypt, Saudi Arabia and Pakistan. ACE Global Markets primarily underwrites P&C insurance through Lloyd’s Syndicate 2488 and AEGL. ACE Global Markets utilizes Syndicate 2488 primarily to underwrite P&C business on a global basis through Lloyd’s worldwide licenses. ACE Global Markets utilizes AEGL to underwrite similar classes of business through its network of U.K. and Continental Europe licenses, and in the U.S. where it is eligible to write E&S business. All business underwritten by ACE Global Markets is accessed through registered brokers. The main lines of business include aviation, property, energy, professional lines, marine, political risk and A&H. ACE Global Markets is an established lead underwriter on a significant portion of the risks underwritten, particularly within the aviation and marine lines of business, and hence is able to set the policy terms and conditions of many of the policies written.

• ACE Asia Pacific is headquartered in Singapore and has an extensive network of operations serving Australia, Hong Kong, India, Indonesia, Korea, Malaysia, New Zealand, Philippines, Singapore, Taiwan, Thailand and Vietnam. ACE Asia Pacific offers a broad range of P&C, A&H and specialty coverages principally directed at large and mid-sized corporations as well as individual consumers. This region also provides management, underwriting and administrative support to our equity investee Huatai Insurance Company of China, Limited.

• ACE Far East is based in Tokyo and offers a broad range of P&C, A&H and personal lines insurance products and services to businesses and consumers in Japan, principally delivered through an extensive agency network.

• ACE Latin America includes business operations throughout Latin America and the Caribbean, including offices in Argentina, Brazil, Chile, Colombia, Ecuador, Mexico, Puerto Rico and Venezuela. ACE Latin America focuses on providing P&C, A&H and specialty personal lines insurance products and services to both large and small commercial clients as well as individual consumers. ACE Latin America distributes its products through brokers (for its commercial business) and direct marketing and sponsored programs (for its consumer business). In December 2006, we entered the Peruvian market with the purchase of Altas Cumbres Life Insurance Company, an insurer that sells credit life and A&H insurance.

Underwriting

Insurance — Overseas General’s operations are diversified by line of business and the geographic spread of risk. A global approach to risk management allows each local operation to underwrite and provided significant capacity. A global approach such as this requires substantial control over each process to ensure best practices and standards are maintained around the world. To do this, the regions are managed as one integrated team.

Clearly defined underwriting authorities, standards, and guidelines are in place in each of the local operations. Global profit centers and product boards ensure consistency of approach and the establishment of best practices throughout the world. A formal underwriting review process is in place to periodically test compliance against standards and guidelines. Experienced underwriting teams maintain underwriting discipline through the use of pricing models, sophisticated catastrophe and risk management methodologies and strict risk selection criteria. Qualified actuaries in each region work closely with the underwriting teams to provide additional expertise in the underwriting process. Centrally-coordinated reinsurance management facilitates appropriate risk transfer and efficient cost-effective use of external reinsurance markets. Insurance — Overseas General’s global claims management team ensures there is a consistent approach to reserving practices and the settlement of claims. The oversight process includes regular operational claims reviews throughout the world to ensure adherence to established guidelines.

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Competitive Environment

ACE International’s primary competitors include U.S.-based companies with global operations, as well as non-U.S. global carriers and indigenous companies in regional and local markets. For the A&H lines of business, locally-based competitors include financial institutions and bank-owned insurance subsidiaries.

Our international operations have the distinct advantage of being part of one of the few international insurance groups with a global network of licensed companies able to write policies on a locally admitted basis. The principal competitive factors that affect the international operations are underwriting expertise and pricing, relative operating efficiency, product differentiation, producer relations and the quality of policyholder services. A competitive strength of our international operations is our global network and breadth of insurance programs, which assist individuals and business organizations to meet their risk management objectives. Insurance operations in over 50 countries also represent a competitive advantage in terms of depth of local technical expertise, accomplishing a spread of risk and offering a global network to service multi-national accounts.

ACE Global Markets is one of the preeminent London market specialty insurers. All lines of business face competition, depending on the business class, from Lloyd’s syndicates, the London market and other major international insurers and reinsurers. Competition for international risks is also seen from domestic insurers in the country of origin of the insured. AGM differentiates itself from competitors through long standing experience in its product lines; its multiple insurance entities (Lloyd’s and AEGL); and the quality of its underwriting and claims service.

Global Reinsurance

Background

The Global Reinsurance segment represents ACE’s reinsurance operations comprising ACE Tempest Re Bermuda, ACE Tempest Re USA, ACE Tempest Re Europe and ACE Tempest Re Canada, which was established in 2006. Global Reinsurance markets its reinsurance products worldwide under the ACE Tempest Re brand name and provides a broad range of coverages to a diverse array of primary P&C companies.

Over the course of the last five years, Global Reinsurance has expanded its portfolio of coverage offerings beyond property catastrophe lines with the aim of building a leading global multi-line reinsurance business within ACE. This expansion has reduced the volatility of ACE’s reinsurance operations by diversifying Global Reinsurance’s business to offer a comprehensive range of products to satisfy client demand. We consider an expanded product offering vital to competing effectively in the reinsurance market, but not at the expense of profitability.

Products and Distribution

Global Reinsurance services clients globally through its three major units: ACE Tempest Re Bermuda, ACE Tempest Re USA and ACE Tempest Re Europe. Through these three operations, we are able to provide a complete portfolio of products on a global basis to clients. Major international brokers submit business to one or more of these units’ underwriting teams who have built strong relationships with both key brokers and clients by explaining their approach and demonstrating consistently open, responsive and dependable service.

Through reinsurance intermediaries, ACE Tempest Re Bermuda principally provides property catastrophe reinsurance globally to insurers of commercial and personal property. Property catastrophe reinsurance on an occurrence basis protects a ceding company against an accumulation of losses covered by its issued insurance policies, arising from a common event or occurrence. ACE Tempest Re Bermuda underwrites reinsurance principally on an excess of loss basis, meaning that its exposure only arises after the ceding company’s accumulated losses have exceeded the attachment point of the reinsurance policy. ACE Tempest Re Bermuda also writes other types of reinsurance on a limited basis for selected clients. Examples include proportional property (reinsurer shares a proportional part of the premiums and losses of the ceding company) and per risk excess of loss treaty reinsurance (coverage applies on a per risk basis rather than per event or aggregate basis), together with specialty lines (catastrophe workers’ compensation and terrorism).

ACE Tempest Re USA writes all lines of traditional and specialty P&C reinsurance for the North American market, with a focus on writing property per risk and casualty reinsurance, including medical malpractice, and surety, principally on a treaty basis, with a weighting towards casualty. This unit’s diversified portfolio is produced through reinsurance intermediaries.

ACE Tempest Re Europe provides treaty reinsurance of P&C business of insurance companies worldwide, with emphasis on non-U.S. and London market risks. ACE Tempest Re Europe writes all lines of traditional and specialty

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property, casualty, marine, aviation, and medical malpractice through our London and Zurich based divisions. The London-based divisions of ACE Tempest Re Europe focus on the development of business sourced through London market brokers and consequently write a diverse book of international business utilizing Lloyd’s global licensing and the Company market licensing. The Zurich-based division focuses on providing reinsurance to continental European insurers via continental European brokers.

ACE Tempest Re Canada commenced writing business during the first quarter of 2007, offering a full array of P&C reinsurance to the Canadian market. ACE Tempest Re Canada provides its coverage through its Canadian company platform and also offers its clients access to Lloyd’s Syndicate 2488.

Underwriting

Global Reinsurance is a disciplined underwriter and has built an underwriting environment, involving both underwriters and actuaries, to provide the necessary controls over the underwriting process. In addition to substantial management oversight, these controls include regular peer reviews, actuarial pricing and reserve support, and catastrophe exposure management using sophisticated modeling software. Global Reinsurance also establishes zonal and peril accumulation limits to avoid concentrations of risk from natural perils.

Rates, policy limits, retentions and other reinsurance terms and conditions are generally established in a worldwide competitive market that evaluates exposure and balances demand for property catastrophe coverage against the available supply. Global Reinsurance is considered a lead reinsurer and is typically involved in the negotiation and quotation of the terms and conditions of the majority of the contracts in which it participates. Deals are structured and priced by teams of underwriters and actuaries using a comprehensive suite of experience and exposure-based actuarial models. This process is designed to ensure that full consideration is given to a complete understanding of the underlying risk profile of the product and that the terms and conditions are appropriate. Each deal is peer-reviewed and approved by other underwriters and actuaries.

Because ACE Tempest Re Bermuda underwrites property catastrophe reinsurance and has large aggregate exposures to natural and man-made disasters, its claims experience generally will involve relatively infrequent events of considerable severity. ACE Tempest Re Bermuda seeks to diversify its property catastrophe reinsurance portfolio to moderate the impact of this severity. The principal means of diversification are by geographic coverage and by varying attachment points and imposing coverage limits per program. Furthermore, ACE Tempest Re Bermuda applies an underwriting process for property catastrophe risks based on models that use exposure data submitted by prospective reinsureds in accordance with requirements set by its underwriters. The data is analyzed using a suite of catastrophe analysis tools, including externally developed event based models licensed from credible vendors as well as proprietary models developed in-house. The output from these catastrophe analysis tools is fed into Global Reinsurance’s proprietary risk management platform (Heuron), enabling it to extensively simulate possible combinations of events affecting the portfolio and price coverages accordingly. Heuron measures the accumulation of exposures and assigns risk-based capital to each new risk that is being underwritten. The amount of risk-based capital required to support the new risk will vary according to the contribution that the new risk makes to existing portfolio accumulations. This unique analytical approach requires exposure data from each cedant within the portfolio. Heuron also provides decision support analysis for capital management, including the purchase of retrocessional coverages.

ACE Tempest Re Europe, ACE Tempest Re USA and ACE Tempest Re Canada write a diversified portfolio of P&C business produced through reinsurance intermediaries, utilizing an underwriting process based on the use of exposure and experience based models, with reliance on data provided by reinsureds. Business written includes a broad range of liability, property and specialty classes, including marine aviation and surety. Business is written on an excess-of-loss and pro-rata basis. Underwriters, actuaries and claims professionals collaborate in a team-oriented environment to develop appropriate loss cost, terms and conditions that fit an individual portfolio. Each transaction is assessed based on its individual merits. Exposure management is considered on both an account level and book of business basis within guidelines provided by senior management. Casualty business has maximum capacity commitments, by line of business, for types of business that can accumulate to any one event; property and specialty businesses establish maximum foreseeable loss by zone. Each deal written is assessed through a risk-based capital return on equity model that provides various scenarios to measure the appropriate pricing and expected returns on capital deployed.

Competitive Environment

The Global Reinsurance segment competes worldwide with major U.S. and non-U.S. reinsurers as well as reinsurance departments of numerous multi-line insurance organizations. Global Reinsurance competes effectively in P&C markets

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worldwide because of its strong capital position, the quality of service provided to customers, the leading role it plays in setting the terms, pricing and conditions in negotiating contracts, and its customized approach to risk selection. While consolidation and closures have reduced its number of competitors, there is still meaningful competition in the marketplace.

Life Insurance and Reinsurance

Background

Life Insurance and Reinsurance includes the operations of ACE Tempest Life Re (ACE Life Re) and ACE International Life (ACE Life).

ACE Life Re helps clients (ceding companies) manage mortality, morbidity, lapse and/or capital market risks embedded in their books of business. ACE Life Re comprises two companies. The first is a Bermuda-based niche player in the life reinsurance market that provides reinsurance coverage to other life insurance companies, focusing on guarantees included in certain fixed and variable annuity products. The second is a U.S.-based traditional life reinsurance company. In May 2006, we announced our expansion into the traditional U.S. life reinsurance marketplace with the acquisition of Hart Life Insurance Company (essentially a shell company) from the Hartford Financial Services Group. Licensed in 49 states and the District of Columbia, Hart Life has been inactive in recent years. Through this company, we are now marketing traditional life reinsurance products and services under our established life reinsurance brand name, ACE Tempest Life Re USA. Based in Stamford, Connecticut, ACE Tempest Life Re USA offers reinsurance capacity for the individual life business utilizing yearly renewable term and coinsurance structures.

ACE Life provides traditional life insurance protection, investment and savings products to individuals in several countries including Thailand, Vietnam, Taiwan, China and Egypt.

Products and Distribution

ACE Life Re markets its products directly to clients as well as through reinsurance intermediaries. The marketing plan seeks to capitalize on the relationships developed by our executive officers and underwriters with members of the actuarial profession and executives at client companies. ACE Life Re targets potential ceding insurers that it believes would benefit from its reinsurance products based on analysis of publicly available information and other industry data. In addition, reinsurance transactions are often placed by reinsurance intermediaries and consultants. ACE Life Re works with such third party marketers in an effort to maintain a high degree of visibility in the reinsurance marketplace. ACE Life Re’s strategy and business does not depend on a single client or a few clients. To date, we have entered into reinsurance agreements with over 30 clients. However, a significant percentage of total revenue and income derives from our core line of business, which is reinsurance of variable annuity guarantees. We anticipate that continued growth as well as expansion into the more traditional life reinsurance lines of business will provide ACE Life Re with more diversified sources of revenue by number of clients and by lines of business.

ACE Life offers a broad portfolio of products including whole life, endowment plans, universal life, personal accident, and term life policies. The policies written by ACE Life generally provide funds for dependents of insureds after death but can also be leveraged as savings vehicles. ACE Life sells to consumers through a variety of distribution channels including agents, direct marketing, sponsor products, telemarketing, work-site marketing and affinity groups.

Underwriting

ACE Life Re underwrites transactions on a qualitative and quantitative basis. The underwriters in this unit are individuals with specialized experience and expertise in the specific products we write. Underwriting guidelines have been developed with the objective of controlling the risks of the reinsurance policies written as well as to determine appropriate pricing levels. The guidelines are amended from time to time in response to changing industry conditions, market developments, changes in technology and other factors.

In implementing the underwriting guidelines, an experienced underwriting team is utilized to select opportunities with acceptable risk/return profiles. Reinsurance business is assumed only after considering many factors, including the type of risks to be covered, actuarial evaluations, historical performance data for the client and the industry as a whole, the client’s retention, the product to be reinsured, pricing assumptions, underwriting standards, reputation and financial strength of the client, the likelihood of establishing a long-term relationship with the client, and the market share of the client. Pricing of reinsurance products is based on ACE Life Re’s sophisticated stochastic modeling techniques and robust actuarial and investment models which incorporate a number of factors. These factors

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include assumptions for mortality, morbidity, expenses, demographics, persistency, investment returns, macroeconomic factors such as inflation and taxation and certain regulatory factors such as reserve and surplus requirements. All of ACE Life Re’s annuity reinsurance treaties, which are non-proportional in nature, incorporate some form of annual claim limit, and many include an aggregate claim limit as well as either an annual or aggregate claim deductible. ACE Life Re’s traditional reinsurance includes both proportional and non-proportional treaties. ACE Life Re also uses modeling software to monitor, measure, and manage the aggregate exposure which is bound by limits set by senior management.

ACE Life applies detailed underwriting procedures designed to assess and quantify insurance risks prior to issuing policies to individuals or groups. Medical examinations are required of applicants for certain products and for life insurance amounts exceeding prescribed limits. Underwriting requirements may vary according to the applicant’s age, policy type, product, or regulatory requirements. ACE Life policies are generally underwritten individually, although standardized underwriting procedures have been adopted for certain low face-amount life insurance coverages.

Competitive Environment

There is little competition for ACE Life Re in the variable annuity reinsurance marketplace. However, downward pressure on prices can result from our clients’ competitive requirements, new reinsurers entering the variable annuity marketplace and the availability of alternative means of managing the variable annuity risk (such as hedging). The life reinsurance market for traditional mortality risk is highly competitive as most of the reinsurance companies are well established, have significant operating histories, strong claims-paying ability ratings, and long-standing client relationships through existing treaties with ceding companies. ACE Life Re competes effectively by leveraging the strength of its client relationships, underwriting expertise and capacity, and our brand name and capital position.

ACE Life faces competition from local and international life insurance companies in each of its markets. ACE’s financial strength and reputation as an entrepreneurial organization with a global presence give ACE Life a strong base from which to compete.

Reinsurance Protection

As part of our risk management strategy, we purchase reinsurance protection to mitigate our exposure to losses, including catastrophes, at an acceptable level. Although reinsurance agreements contractually obligate our reinsurers to reimburse us for the agreed-upon portion of gross paid losses, they do not discharge our primary liability and thus we remain liable for the gross direct loss. In certain countries, reinsurer selection is limited by certain local laws or regulations. In those areas where there is more freedom of choice, the counter-party is selected based upon financial strength, financial strength ratings, management and line of business expertise. In support of this process, we maintain an ACE authorized reinsurer list that stratifies these authorized reinsurers by classes of business and acceptable limits. This list is maintained by our Reinsurance Security Committee, a committee comprised of senior management personnel, and a dedicated reinsurer security team. Changes to the list are authorized by ACE’s Chief Risk Officer. The reinsurers on the authorized list and potential new markets are regularly reviewed, and the list may be modified following these reviews. In addition to the authorized list, there is a formal exception process that allows reinsurance buyers to use reinsurers already on the authorized list for higher limits or different lines of business, for example, or other reinsurers not on the authorized list if their use is supported by compelling business reasons for a particular reinsurance program.

A separate policy and process exists for captive reinsurance companies. Generally, these reinsurance companies are established by our clients or our clients have an interest in them. It is generally our policy to obtain collateral equal to the expected losses that may be ceded to the captive. Where appropriate, exceptions to the collateral requirement are granted but only after senior management review. Specific collateral guidelines and an exception process are in place for ACE USA and Insurance - Overseas General, both of which have credit management units evaluating the captive’s credit quality and that of their parent company. The credit management units, working with actuarial, determine reasonable exposure estimates (collateral calculations), ensure receipt of collateral in a form acceptable to the Company and coordinate collateral adjustments as and when needed. Currently financial reviews and expected loss evaluations are performed annually for active captive accounts and as needed for run-off exposures. In addition to collateral, parental guarantees are often used to enhance the credit quality of the captive.

In general, we seek to place our reinsurance with highly rated companies with which we have a strong trading relationship. For more information refer to “Catastrophe Exposure Management” and “Natural Catastrophe Reinsurance Program”, under Item 7, and Note 8 to the Consolidated Financial Statements, under Item 8.

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Unpaid Losses and Loss Expenses

We establish reserves for unpaid losses and loss expenses, which are estimates of future payments of reported and unreported claims for losses and related expenses, with respect to insured events that have occurred. The process of establishing loss reserves for P&C claims can be complex and is subject to considerable variability as it requires the use of informed estimates and judgments based on circumstances known at the date of accrual. These estimates and judgments are based on numerous factors, and may be revised as additional experience and other data become available and are reviewed, as new or improved methodologies are developed or as current laws change. We have actuarial staff in each of our operating segments who analyze insurance reserves and regularly evaluate the levels of loss reserves, taking into consideration factors that may impact the ultimate settlement value of the unpaid losses and loss expenses. Any such revisions could result in future changes in estimates of losses or reinsurance recoverable and would be reflected in our results of operations in the period in which the estimates are changed. Losses and loss expenses are charged to income as incurred. The reserve for unpaid losses and loss expenses represents the estimated ultimate losses and loss expenses less paid losses and loss expenses, and comprises case reserves and incurred but not reported loss reserves (IBNR). With the exception of certain structured settlements, for which the timing and amount of future claim payments are reliably determinable, our loss reserves are not discounted for time value. In connection with these structured settlements, we carry reserves of $118 million, net of discount, at December 31, 2006.

We implicitly consider the impact of inflation in estimating the reserve for unpaid losses and loss expenses. There is no precise method for subsequently evaluating the adequacy of the consideration given to inflation, since claim settlements are affected by many factors.

During the loss settlement period, which can be many years in duration, additional facts regarding individual claims and trends often will become known. As these become apparent, case reserves may be adjusted by allocation from IBNR without any change in the overall reserve. In addition, application of statistical and actuarial methods may require the adjustment of the overall reserves upward or downward from time to time. Accordingly, the ultimate settlement of losses may be significantly greater than or less than reported loss and loss expense reserves.

We have considered asbestos and environmental (A&E) claims and claims expenses in establishing the liability for unpaid losses and loss expenses and have developed reserving methods which incorporate new sources of data with historical experience to estimate the ultimate losses arising from A&E exposures. The reserves for A&E claims and claims expenses represent management’s best estimate of future loss and loss expense payments and recoveries which are expected to develop over the next several decades. We continuously monitor evolving case law and its effect on environmental and latent injury claims and we monitor A&E claims activity quarterly and perform a full reserve review annually.

For each product line, management, in conjunction with internal actuaries, develop a “best estimate” of the ultimate settlement value of the unpaid losses and loss expenses which they believe provide a reasonable estimate of the required reserve. We evaluate our estimates of reserves quarterly in light of developing information and discussions and negotiations with our insureds. While we are unable at this time to determine whether additional reserves, which could have a material adverse effect upon our financial condition, results of operations and cash flows, may be necessary in the future, we believe that our reserves for unpaid losses and loss expenses are adequate as of December 31, 2006.

For more information refer to “Critical Accounting Estimates—Unpaid losses and loss expenses” under Item 7 and to Note 10 to our Consolidated Financial Statements, under Item 8.

The “Analysis of Losses and Loss Expenses Development” table shown below presents for each balance sheet date over the period 1996-2006, the gross and net loss and loss expense reserves recorded at the balance sheet date and subsequent payments from the net reserves. The reserves represent the amount required for the estimated future settlement value of liabilities incurred at or prior to the balance sheet date and those estimates may change subsequent to the balance sheet date as new information emerges regarding the ultimate settlement value of the liability. Accordingly, the table also presents through to December 31, 2006, for each balance sheet date, the cumulative impact of subsequent valuations of the liabilities incurred at the original balance sheet date. The data in the table is presented in accordance with reporting requirements of the Securities and Exchange Commission (SEC). This table should be interpreted with care by those not familiar with its format or those who are familiar with other triangulations arranged by origin year of loss such as accident or underwriting year rather than balance sheet date, as shown below. To clarify the interpretation of the table we use the reserves established at December 31, 1999, in the following example.

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• The top two lines of the table show for successive balance sheet dates the gross and net unpaid losses and loss expenses recorded as provision for liabilities incurred at or prior to each balance sheet date. It can be seen that at December 31, 1999, a reserve of $9.057 billion net of reinsurance had been established.

• The upper (paid) triangulation presents the net amounts paid as of periods subsequent to the balance sheet date. Hence in the 2000 financial year, $2.663 billion of payments were made from the December 31, 1999 reserve balance established for liabilities incurred prior to the 2000 financial year. At the end of the 2006 financial year this block of liabilities had resulted in cumulative net payments of $7.093 billion.

• The lower triangulation within the table shows the revised estimate of the net liability originally recorded at each balance sheet date as of the end of subsequent financial years. With the benefit of actual loss emergence and hindsight over the intervening period the net liabilities incurred as of December 31, 1999 are now estimated to be $10.521 billion, rather than the original estimate of $9.057 billion. One of the key drivers of this change has been adverse development on latent claims which we categorize as asbestos and environmental losses and other run-off liabilities covered under the NICO reinsurance treaties. Of the cumulative deficiency of $1.464 billion recognized in the seven years since December 31, 1999, $0.426 billion relates to non-latent claims and $1.038 billion relates to latent claims. The deficiency of $1.464 billion was identified and recorded as follows; $45 million redundant in 2000, $8 million deficient in 2001, $558 million deficient in 2002, $149 million deficient in 2003, $874 million deficient in 2004, $121 million favorable in 2005 and $41 million deficient in 2006.

• Importantly, the cumulative deficiency or redundancy for different balance sheet dates are not independent and therefore should not be added together. In the last year, we have revised our estimate of the December 31, 1999 liabilities from $10.480 billion to $10.521 billion. This adverse development of $41 million will also be included in each column to the right of the December 31, 1999 column to recognize that this additional amount was also required in the reserves established for each annual balance sheet date from December 31, 2000 to December 31, 2006.

The loss development table shows that our original estimate of the net unpaid loss and loss expense requirement at December 31, 2005 of $20.458 billion has, with the benefit of actual loss emergence and hindsight, been revised to $20.446 billion at December 31, 2006. This favorable movement of $12 million is referred to as prior period development and is the net result of a number of underlying movements both favorable and adverse. The key underlying movements are discussed in more detail within the “Segment Operating Results” section of Item 7.

The bottom lines of the table show the re-estimated amount of previously recorded gross liabilities at December 31, 2006, together with the change in reinsurance recoverable. Similar to the net liabilities, the cumulative redundancy or deficiency on the gross liability is the difference between the gross liability originally recorded and the re-estimated gross liability at December 31, 2006. For example, with respect to the gross unpaid loss and loss expenses of $16.713 billion for 1999, by December 31, 2006, this gross liability was re-estimated to be $22.808 billion, resulting in the cumulative deficiency on the gross liability originally recorded for the 1999 balance sheet year of $6.095 billion. This deficiency relates primarily to U.S. liabilities, including A&E liabilities for 1995 and prior. The gross deficiency results in a net deficiency of $1.464 billion as a result of substantial reinsurance coverage that reduces the gross loss; approximately $2.2 billion was covered by reinsurance placed when the risks were originally written and $1.25 billion of the remaining liability has been ceded to the National Indemnity Company (NICO).

We do not consider it appropriate to extrapolate future deficiencies or redundancies based upon the table, as conditions and trends that have affected development of the liability in the past may not necessarily recur in the future. We believe that our current estimates of net liabilities appropriately reflect our current knowledge of business profile and the prevailing market, social, legal and economic conditions while giving due consideration to historical trends and volatility evidenced in our markets over the longer term. The key issues and considerations involved in establishing our estimate of the net liabilities are discussed in more detail within the “Critical Accounting Estimates—Unpaid losses and loss expenses” section of Item 7.

On July 2, 1999, we changed our fiscal year-end from September 30 to December 31. As a result, the information provided for the 1999 year is actually for the 15-month period from October 1, 1998, through December 31, 1999. Prior to December 31, 1999, the net unpaid losses and loss expenses are in respect of annual periods ending on September 30 of each year. On November 1, 1993, we acquired CODA, on July 1, 1996, we acquired ACE Tempest Re, and on July 9, 1998, we acquired Tarquin. CODA, ACE Tempest Re and Tarquin’s loss experience have been included in the table as if each of these companies had been our wholly-owned subsidiaries from their inception. On January 2, 1998, we acquired ACE US Holdings, on April 1, 1998, we acquired CAT Limited, and on July 2, 1999, we acquired ACE INA (CIGNA’s P&C business). The unpaid loss information for ACE US Holdings, CAT Limited and ACE INA has been included in the table commencing in the year of acquisition. As a result, 1999 includes net reserves of $6.8 billion related to ACE

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INA at the date of acquisition and subsequent development thereon. On April 28, 2004, we completed the sale of 65.3 percent of Assured Guaranty. The historical loss information for Assured Guaranty has been removed from the table.

(1) The 1999 year is for the 15-month period ended December 31, 1999.

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Net losses and loss expenses incurred for the year ended December 31, 2006 were $7.1 billion, compared with $8.6 billion and $7.7 billion in 2005 and 2004, respectively. Net losses and loss expenses incurred for 2006 include $12 million of favorable prior period development, 2005 and 2004 include $86 million and $547 million, respectively, of adverse prior period development. In 2004, we increased our reserve for asbestos, environmental and other run-off claims by $465 million. The net additions comprised A&E reserve increases of $554 million including the provision for uncollectible reinsurance of $95 million and favorable prior period development of $89 million in other run-off reserves. More information regarding prior period development is included in the “Segment Operating Results” section of Item 7.

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Investments

Our principal investment objective is to ensure that funds will be available to meet our primary insurance and reinsurance obligations. Within this broad liquidity constraint, the investment portfolio’s structure seeks to maximize return subject to specifically-approved guidelines of overall asset classes, credit quality, liquidity and volatility of expected returns. As such, our investment portfolio is invested primarily in investment-grade fixed-income securities as measured by the major rating agencies.

The management of our investment portfolio is the responsibility of ACE Asset Management. ACE Asset Management operates principally to guide and direct our investment process. In this regard, ACE Asset Management:

• conducts formal asset allocation modeling for each of the ACE subsidiaries, providing formal recommendations for the portfolio’s structure;

•establishes recommended investment guidelines that are appropriate to the prescribed asset allocation targets;

• provides the analysis, evaluation, and selection of our external investment advisors;

• establishes and develops investment-related analytics to enhance portfolio engineering and risk control;

• monitors and aggregates the correlated risk of the overall investment portfolio; and

• provides governance over the investment process for each of our operating companies to ensure consistency of approach and adherence to investment guidelines.

For the portfolio, we determine allowable, targeted asset allocation and ranges for each of the operating segments. These asset allocation targets are derived from sophisticated asset and liability modeling that measures correlated histories of returns and volatility of returns. Allowable investment classes are further refined through analysis of our operating environment, including expected volatility of cash flows, overall capital position, regulatory and rating agency considerations.

The Finance and Investment Committee of the Board of Directors approves asset allocation targets and reviews our investment policy to ensure that it is consistent with our overall goals, strategies and objectives. Overall investment guidelines are approved by the Finance and Investment Committee to ensure that appropriate levels of portfolio liquidity, credit quality, diversification and volatility are maintained. In addition, the Finance and Investment Committee systematically reviews the portfolio’s exposures to capture any potential violations of investment guidelines.

Within the guidelines and asset allocation parameters established by the Finance and Investment Committee, individual investment committees of the operating segments determine tactical asset allocation. Additionally, these committees review all investment-related activity that affects their operating company, including the selection of outside investment advisors, proposed asset allocations changes, and the systematic review of investment guidelines.

For additional information regarding the investment portfolio, including breakdowns of the sector and maturity distributions, refer to Note 7 to the Consolidated Financial Statements, under Item 8.

Regulation

Bermuda Operations

In Bermuda, our insurance subsidiaries are principally regulated by the Insurance Act 1978 (as amended) and related regulations (the Act). The Act imposes solvency and liquidity standards as well as auditing and reporting requirements, and grants the Bermuda Monetary Authority (the Authority) powers to supervise, investigate and intervene in the affairs of insurance companies. Significant requirements include the appointment of an independent auditor, the appointment of a loss reserve specialist and the filing of the Annual Statutory Financial Return with the Supervisor of Insurance (the Supervisor). The Supervisor is the chief administrative officer under the Act. We must comply with provisions of the Companies Act 1981 regulating the payment of dividends and distributions. A Bermuda company may not declare or pay a dividend or make a distribution out of contributed surplus if there are reasonable grounds for believing that: (a) the company is, or would after the payment be, unable to pay its liabilities as they become due; or (b) the realizable value of the company’s assets would thereby be less than the aggregate of its liabilities and its issued share capital and share premium accounts. Further, an insurer may not declare or pay any dividends during any financial year if it would cause the insurer to fail to meet its relevant margins, and an insurer which fails to meet its relevant margins on the last day of any financial year may not, without the approval of the Minister, declare or pay any dividends during the next financial year. In addition, some of ACE’s Bermuda subsidiaries qualify as “Class 4” insurers

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and may not in any financial year pay dividends which would exceed 25 percent of their total statutory capital and surplus, as shown on their statutory balance sheet in relation to the previous financial year, unless they file a solvency affidavit at least seven days in advance.

The Supervisor may appoint an inspector with extensive powers to investigate the affairs of an insurer if he believes that an investigation is required in the interest of the insurer’s policyholders or persons who may become policyholders. In order to verify or supplement information otherwise provided to him, the Supervisor may direct an insurer to produce documents or information relating to matters connected with the insurer’s business. If it appears to the Supervisor that there is a risk of the insurer becoming insolvent, or that the insurer is in breach of the Act or any conditions of its registration under the Act, the Supervisor may direct the insurer not to take on any new insurance business, not to vary any insurance contract if the effect would be to increase the insurer’s liabilities, not to make certain investments, to realize certain investments, to maintain in, or transfer to the custody of a specified bank certain assets, not to declare or pay any dividends or other distributions, or to restrict the making of such payments and/or to limit its premium income.

The Act requires every insurer to appoint a principal representative resident in Bermuda and to maintain a principal office in Bermuda. The principal representative must be knowledgeable in insurance and is responsible for arranging the maintenance and custody of the statutory accounting records and for filing the annual Statutory Financial Return.

U.S. Operations

Our U.S. insurance subsidiaries are subject to extensive regulation and supervision by the states in which they do business. The laws of the various states establish departments of insurance with broad authority to regulate, among other things: the standards of solvency that must be met and maintained, the licensing of insurers and their producers, approval of policy forms and rates, the nature of and limitations on investments, restrictions on the size of the risks which may be insured under a single policy, deposits of securities for the benefit of policyholders, requirements for the acceptability of reinsurers, periodic examinations of the affairs of insurance companies, the form and content of reports of financial condition required to be filed and the adequacy of reserves for unearned premiums, losses and other purposes.

Our U.S. insurance subsidiaries are required to file detailed annual and quarterly reports with state insurance regulators in each of the states in which they do business. In addition, the U.S. insurance subsidiaries’ operations and accounts are subject to examination at regular intervals by state regulators.

All states have enacted legislation that regulates insurance holding companies. This legislation provides that each insurance company in the system is required to register with the insurance department of its state of domicile and furnish information concerning the operations of companies within the holding company system which may materially affect the operations, management or financial condition of the insurers within the system. All transactions within a holding company system must be fair and equitable. Notice to the insurance departments is required prior to the consummation of transactions affecting the ownership or control of an insurer and of certain material transactions between an insurer and an entity in its holding company system; in addition, certain transactions may not be consummated without the department’s prior approval.

Statutory surplus is an important measure utilized by the regulators and rating agencies to assess our U.S. insurance subsidiaries’ ability to support business operations and provide dividend capacity. Our U.S. insurance subsidiaries are subject to various state statutory and regulatory restrictions that limit the amount of dividends that may be paid without prior approval from regulatory authorities. These restrictions differ by state, but are generally based on calculations incorporating statutory surplus, statutory net income, and/or investment income.

The National Association of Insurance Commissioners (NAIC) has a risk-based capital requirement for P&C insurance companies. This risk-based capital formula is used by many state regulatory authorities to identify insurance companies which may be undercapitalized and which merit further regulatory attention. These requirements are designed to monitor capital adequacy using a formula which prescribes a series of risk measurements to determine a minimum capital amount for an insurance company, based on the profile of the individual company. The ratio of a company’s actual policyholder surplus to its minimum capital requirement will determine whether any state regulatory action is required. There are progressive risk-based capital failure levels which trigger more stringent regulatory action. If an insurer’s policyholders’ surplus falls below the Mandatory Control Level (70 percent of the Authorized Control Level, as defined by the NAIC), the relevant insurance commissioner is required to place the insurer under regulatory control. However, an insurance commissioner may allow a P&C company operating below the Mandatory

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Control Level that is writing no business and is running off its existing business to continue its run-off. Brandywine is running off its liabilities consistent with the terms of an order issued by the Insurance Commissioner of Pennsylvania. This includes periodic reporting obligations to the Pennsylvania Insurance Department.

In November 2002, the U.S. Congress passed the Terrorism Risk Insurance Act (TRIA), which was amended and restated in 2005. TRIA was enacted to ensure the availability of insurance coverage for certain types of terrorist acts in the U.S. and requires that qualifying insurers offer terrorism insurance coverage in all P&C insurance policies on terms not materially different than terms applicable to other losses. The U.S. federal government covers 90 percent (85 percent for acts of terrorism occurring in 2007) of the losses from covered certified acts of terrorism on commercial risks in the United States only, in excess of a specified deductible amount calculated as a percentage of an affiliated insurance group’s prior year premiums on commercial lines policies covering risks in the U.S. This specified deductible amount is 17.5 percent of such premiums for losses occurring in 2006, and 20 percent of such premiums for losses occurring in 2007. Further, to trigger coverage under TRIA, the aggregate industry P&C insurance losses resulting from an act of terrorism must exceed $5 million prior to April 2006, $50 million from April 2006 through December 2006, and $100 million for acts of terrorism occurring in 2007. TRIA applies only to losses resulting from attacks that have been committed by individuals on behalf of a foreign person or foreign interest, and does not cover acts of purely domestic terrorism. Further, any such attack must be certified as an “act of terrorism” by the U.S. federal government, and such decision is not subject to judicial review. TRIA will expire on December 31, 2007, and there can be no assurance that it will be extended beyond that date or as to the terms of any such extension.

Our U.S. subsidiaries are also subject to the general laws of the states in which they do business. ACE has received numerous subpoenas, interrogatories, and civil investigative demands in connection with the pending investigations of insurance industry practices. These inquiries have been issued by a number of attorneys general, state departments of insurance, and state and federal regulatory authorities, including the New York Attorney General (NYAG), the Pennsylvania Department of Insurance, the SEC, and the United States Attorney for the Southern District of New York. These inquiries seek information concerning underwriting practices and non-traditional or loss mitigation insurance products. On April 26, 2006, ACE reached a settlement with the Attorneys General of New York, Illinois and Connecticut and the New York Insurance Department pursuant to which ACE received from these authorities an Assurance of Discontinuance (AOD). Under the AOD, these regulators agreed not to file certain litigation against ACE relating to their investigation of certain business practices, and ACE agreed to pay $80 million ($66 million after tax) without admitting any liability, and to adopt certain business reforms. While the Attorneys General of New York, Illinois and Connecticut and the New York Department of Insurance have resolved investigations of ACE, other investigations and related civil litigation continue. ACE is cooperating and will continue to cooperate with such inquiries. Information on the insurance industry investigations and related matters is set forth in Note 12 to our Consolidated Financial Statements, under Item 8.

International Operations

The extent of insurance regulation varies significantly among the countries in which the non-U.S. ACE operations conduct business. While each country imposes licensing, solvency, auditing and financial reporting requirements, the type and extent of the requirements differ substantially. For example:

• in some countries, insurers are required to prepare and file quarterly financial reports, and in others, only annual reports;

• some regulators require intermediaries to be involved in the sale of insurance products, whereas other regulators permit direct sales contact between the insurer and the customer;

• the extent of restrictions imposed upon an insurer’s use of foreign reinsurance vary;

• policy form filing and rate regulation vary by country;

• the frequency of contact and periodic on-site examinations by insurance authorities differ by country; and

• regulatory requirements relating to insurer dividend policies vary by country.

Significant variations can also be found in the size, structure and resources of the local regulatory departments that oversee insurance activities. Certain regulators prefer close relationships with all subject insurers and others operate a risk-based approach.

ACE operates in some countries through our subsidiaries and in some countries through branches of those subsidiaries. Local capital requirements applicable to a subsidiary generally include its branches. Certain ACE companies are jointly owned with local companies to comply with legal requirements for local ownership. Other legal requirements include discretionary licensing procedures, compulsory cessions of reinsurance, local retention of funds and

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records, and foreign exchange controls. ACE’s international companies are also subject to multinational application of certain U.S. laws. The complex regulatory environments in which ACE operates are subject to change and are regularly monitored.

Tax Matters

Refer to “Risk Factors”, under Item 1A below, and Note 2 to the Consolidated Financial Statements, under Item 8.

Factors that could have a material impact on our results of operations or financial condition are outlined below. Additional risks not presently known to us or that we currently deem insignificant may also impair our business or results of operations as they become known facts or as facts and circumstances change. Any of the risks described below could result in a significant or material adverse effect on our results of operations or financial condition.

Business

Our financial condition could be adversely affected by the occurrence of natural and man-made disasters.

We have substantial exposure to losses resulting from natural disasters, man-made catastrophes and other catastrophic events. Catastrophes can be caused by various events, including hurricanes, typhoons, earthquakes, hailstorms, explosions, severe winter weather, fires, war, acts of terrorism, political instability and other natural or man-made disasters. The incidence and severity of catastrophes are inherently unpredictable and our losses from catastrophes could be substantial. The occurrence of claims from catastrophic events is likely to result in substantial volatility in our results of operations or financial condition for any fiscal quarter or year. Increases in the values and concentrations of insured property may increase the severity of these occurrences in the future. Although we attempt to manage our exposure to such events through the use of underwriting controls and purchase of third-party reinsurance, catastrophic events are inherently unpredictable and the actual nature of such events when they occur could be more frequent or severe than contemplated in our pricing and risk management expectations. As a result, the occurrence of one or more catastrophic events could have a material adverse effect on our results of operations or financial condition. Refer to “Catastrophe Exposure Management” under Item 7 for more information.

If actual claims exceed our loss reserves, our financial results could be adversely affected.

Our results of operations and financial condition depend upon our ability to assess accurately the potential losses associated with the risks that we insure and reinsure. We establish reserves for unpaid losses and loss expenses, which are estimates of future payments of reported and unreported claims for losses and related expenses, with respect to insured events that have occurred at or prior to the date of the balance sheet. The process of establishing reserves is highly complex and is subject to considerable variability as it requires the use of informed estimates and judgments. These estimates and judgments are based on numerous factors, and may be revised as additional experience and other data become available and are reviewed, as new or improved methodologies are developed or as current laws or interpretations thereof change.

We have actuarial staff in each of our operating segments who analyze insurance reserves and regularly evaluate the levels of loss reserves. Any such evaluations could result in future changes in estimates of losses or reinsurance recoverable and would be reflected in our results of operations in the period in which the estimates are changed. Losses and loss expenses are charged to income as incurred. Reserves for unpaid losses and loss expenses represent the estimated ultimate losses and loss expenses less paid losses and loss expenses, and is comprised of case reserves and IBNR. During the loss settlement period, which can be many years in duration for some of our lines of business, additional facts regarding individual claims and trends often will become known. As these become apparent, case reserves may be adjusted by allocation from IBNR without any change in overall reserves. In addition, application of statistical and actuarial methods may require the adjustment of overall reserves upward or downward from time to time.

Included in our liabilities for losses and loss expenses are liabilities for latent claims such as A&E. These claims are principally related to claims arising from remediation costs associated with hazardous waste sites and bodily-injury claims related to exposure to asbestos products and environmental hazards. The estimation of these liabilities is subject to many complex variables including: the current legal environment; specific settlements that may be used as

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precedents to settle future claims; assumptions regarding multiple recoveries by claimants against various defendants; the ability of a claimant to bring a claim in a state in which they have no residency or exposure; the ability of a policyholder to claim the right to non-products coverage; whether high-level excess policies have the potential to be accessed given the policyholder’s claim trends and liability situation; payments to unimpaired claimants; and the potential liability of peripheral defendants.

Accordingly, the ultimate settlement of losses may be significantly greater or less than the loss and loss expense reserves held at the date of the balance sheet. If our loss reserves are determined to be inadequate, we will be required to increase loss reserves at the time of such determination and our net income will be reduced. If the increase in loss reserves is large enough, we could incur an operating loss and a reduction of our capital. Refer to “Asbestos and Environmental and Other Run-Off Liabilities”, under Item 7 and Note 10 to our Consolidated Financial Statements, under Item 8.

The effects of emerging claim and coverage issues on our business are uncertain.

As industry practices and legal, judicial, social and other environmental conditions change, unexpected and unintended issues related to claims and coverage may emerge. These issues may adversely affect our business by either extending coverage beyond our underwriting intent or by increasing the frequency and severity of claims. In some instances, these changes may not become apparent until some time after we have issued insurance or reinsurance contracts that are affected by the changes. As a result, the full extent of liability under our insurance or reinsurance contracts may not be known for many years after a contract is issued.

The failure of any of the loss limitation methods we employ could have an adverse effect on our results of operations or financial condition.

We seek to limit our loss exposure by writing a number of our insurance and reinsurance contracts on an excess of loss basis. Excess of loss insurance and reinsurance indemnifies the insured against losses in excess of a specified amount. In addition, we limit program size for each client and purchase third-party reinsurance for our own account. In the case of our assumed proportional reinsurance treaties, we seek per occurrence limitations or loss and loss expense ratio caps to limit the impact of losses ceded by the client. In proportional reinsurance, the reinsurer shares a proportional part of the premiums and losses of the reinsured. We also seek to limit our loss exposure by geographic diversification. Geographic zone limitations involve significant underwriting judgments, including the determination of the area of the zones and the inclusion of a particular policy within a particular zone’s limits. Various provisions of our policies, such as limitations or exclusions from coverage or choice of forum negotiated to limit our risks, may not be enforceable in the manner we intend. As a result, one or more catastrophic or other events could result in claims that substantially exceed our expectations, which could have an adverse effect on our results of operations or financial condition.

We may be unable to purchase reinsurance, and if we successfully purchase reinsurance, we are subject to the possibility of non-payment.

We purchase reinsurance to protect certain ACE companies against catastrophes, to increase the amount of protection we can provide our clients and as part of our overall risk management strategy. Our reinsurance business also purchases some retrocessional protection. A retrocessional reinsurance agreement allows a reinsurer to cede to another company all or part of the reinsurance that was originally assumed by the reinsurer. A reinsurer’s or retrocessionaire’s insolvency, or inability or unwillingness to make timely payments under the terms of its reinsurance agreement with us, could have an adverse effect on us because we remain liable to the insured. From time to time, market conditions have limited, and in some cases have prevented, insurers and reinsurers from obtaining the types and amounts of reinsurance or retrocessional reinsurance that they consider adequate for their business needs.

There is no guarantee our desired amounts of reinsurance or retrocessional reinsurance will be available in the marketplace in the future. In addition to capacity risk, the remaining capacity may not be on terms we deem appropriate or acceptable or with companies with whom we want to do business. Finally, we face some degree of counter-party risk whenever we purchase reinsurance or retrocessional reinsurance. Consequently, the insolvency, inability or unwillingness of any of our present or future reinsurers to make timely payments to us under the terms of our reinsurance or retrocessional agreements could have an adverse effect on us. At December 31, 2006, we had $14.6 billion of reinsurance recoverables, net of reserves for uncollectible recoverables.

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As part of the restructuring of INA Financial Corporation and its subsidiaries that occurred in 1996, Insurance Company of North America (INA) was divided into two separate corporations: an active insurance company that retained the INA name and continued to write P&C business and an inactive run-off company, now called Century Indemnity Company (Century). The A&E exposures of substantially all of INA’s U.S. P&C companies, now our subsidiaries, were either allocated to Century (as a result of the restructuring) or reinsured to subsidiaries of Brandywine, primarily Century. Certain of our subsidiaries are primarily liable for A&E and other exposures they have reinsured to Century. As of December 31, 2006, the aggregate reinsurance balances ceded by our active subsidiaries to Century were $1.6 billion. Should Century experience adverse loss reserve development in the future and should Century be placed into rehabilitation or liquidation, the reinsurance recoverables due to Century’s affiliates would be payable only after the payment in full of certain expenses and liabilities, including administrative expenses and direct policy liabilities. Thus, the intercompany reinsurance recoverables would be at risk to the extent of the shortage of assets remaining to pay these recoverables. While we believe the intercompany reinsurance recoverables from Century are not impaired at this time, we cannot assure you that adverse development with respect to Century’s loss reserves will not result in Century’s insolvency, which could result in our recognizing a loss to the extent of any uncollectible reinsurance from Century. For further information regarding our reinsurance exposure to Century, refer to “Asbestos and Environmental and Other Run-Off Liabilities”, under Item 7.

Financial Strength Ratings

A decline in our ratings could affect our standing among brokers and customers and cause our premiums and earnings to decrease.

Ratings have become an increasingly important factor in establishing the competitive position of insurance and reinsurance companies. The objective of these rating systems is to provide an opinion of an insurer’s financial strength and ability to meet ongoing obligations to its policyholders. Our financial strength ratings reflect the rating agencies’ opinions of our financial strength, are not evaluations directed to investors in our securities and are not recommendations to buy, sell or hold our securities. If our financial strength ratings are reduced from their current levels by one or more of these agencies, our competitive position in the insurance industry could suffer and it would be more difficult for us to market our products. A downgrade, therefore, could result in a substantial loss of business as insureds, ceding companies and brokers move to other insurers and reinsurers with higher ratings. We cannot give any assurance regarding whether or to what extent any of the rating agencies may downgrade our ratings in the future.

Loss of Key Executives

We could be adversely affected by the loss of one or more key executives or by an inability to attract and retain qualified personnel.

Our success depends on our ability to retain the services of our existing key executives and to attract and retain additional qualified personnel in the future. The loss of the services of any of our key executives or the inability to hire and retain other highly qualified personnel in the future could adversely affect our ability to conduct our business. We do not maintain key person life insurance policies with respect to our employees.

Many of our senior executives working in Bermuda, including our President and Chief Executive Officer, our Chief Financial Officer, our Chief Accounting Officer, our Chief Actuary and our General Counsel, are not Bermudian. Under Bermuda law, non-Bermudians (other than spouses of Bermudians and holders of permanent resident’s certificates) may not engage in any gainful occupation in Bermuda without an appropriate governmental work permit. Our success may depend in part on the continued services of key employees in Bermuda. A work permit may be granted or renewed upon showing that, after proper public advertisement, no Bermudian (or spouse of a Bermudian or holder of a permanent resident’s certificate) is available who meets the minimum standards reasonably required by the employer. The Bermuda government’s policy places a six-year term limit on individuals with work permits, subject to certain exemptions for key employees. A work permit may be issued with an expiry date that is one to five years later and no assurances can be given that any work permit will be issued or, if issued, renewed upon the expiration of the relevant term.

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Reliance on Brokers

Since we depend on a few brokers for a large portion of our revenues, loss of business provided by any one of them could adversely affect us.

We market our insurance and reinsurance worldwide primarily through insurance and reinsurance brokers. Marsh, Inc. and its affiliates and Aon Corporation and its affiliates provided approximately 20 percent and 11 percent, respectively, of our gross premiums written in the year ended December 31, 2006. Loss of all or a substantial portion of the business provided by one or more of these brokers could have a material adverse effect on our business.

Our reliance on brokers subjects us to their credit risk.

In accordance with industry practice, we generally pay amounts owed on claims under our insurance and reinsurance contracts to brokers, and these brokers, in turn, pay these amounts over to the clients that have purchased insurance or reinsurance from us. Although the law is unsettled and depends upon the facts and circumstances of the particular case, in some jurisdictions, if a broker fails to make such a payment, we might remain liable to the insured or ceding insurer for the deficiency. Conversely, in certain jurisdictions, when the insured or ceding insurer pays premiums for these policies to brokers for payment over to us, these premiums might be considered to have been paid and the insured or ceding insurer will no longer be liable to us for those amounts, whether or not we have actually received the premiums from the broker. Consequently, we assume a degree of credit risk associated with brokers with whom we transact business. However, due to the unsettled and fact-specific nature of the law, we are unable to quantify our exposure to this risk. To date, we have not experienced any material losses related to these credit risks.

Liquidity

Our investment performance may affect our financial results and ability to conduct business.

Our funds are invested by professional investment management firms under the direction of our management team in accordance with investment guidelines approved by the Finance and Investment Committee of the Board of Directors. Although our investment guidelines stress diversification of risks and conservation of principal and liquidity, our investments are subject to market risks, as well as risks inherent to individual securities. The volatility of our loss claims may force us to liquidate securities, which may cause us to incur capital losses. Investment losses could significantly decrease our book value, thereby affecting our ability to conduct business.

We may be adversely affected by interest rate changes.

Our operating results are affected by the performance of our investment portfolio. Our investment portfolio contains fixed income investments and may be adversely affected by changes in interest rates. Volatility in interest rates could also have an adverse effect on our investment income and operating results. For example, if interest rates decline, funds reinvested will earn less than the maturing investment.

Interest rates are highly sensitive to many factors, including monetary and fiscal policies, and domestic and international political conditions. Although we take measures to manage the risks of investing in a changing interest rate environment, we may not be able to effectively mitigate interest rate sensitivity. Our mitigation efforts include maintaining a high quality portfolio with a relatively short duration to reduce the effect of interest rate changes on book value. A significant increase in interest rates could have an adverse effect on our book value. Refer to “Quantitative and Qualitative Disclosures about Market Risk – Interest rate risk”, under Item 7A.

We may require additional capital in the future, which may not be available or may only be available on unfavorable terms.

Our future capital requirements depend on many factors, including our ability to write new business successfully and to establish premium rates and reserves at levels sufficient to cover losses. We may need to raise additional funds through financings. Any equity or debt financing, if available at all, may be on terms that are not favorable to us. In the case of equity financings, dilution to our shareholders could result, and in any case such securities may have rights, preferences and privileges that are senior to those of our Ordinary Shares. If we cannot obtain adequate capital on favorable terms or at all, our business, operating results and financial condition could be adversely affected.

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Exchange Rates

Our operating results may be adversely affected by currency fluctuations.

Our functional currency is the U.S. dollar. Many of our non-U.S. companies maintain both assets and liabilities in local currencies. Therefore, foreign exchange risk is generally limited to net assets denominated in those foreign currencies. Foreign exchange risk is reviewed as part of our risk management process. Locally required capital levels are invested in home currencies in order to satisfy regulatory requirements, and to support local insurance operations. The principal currencies creating foreign exchange risk are the British pound sterling, the Euro dollar and the Canadian dollar. For the year ended December 31, 2006, approximately nine percent of our net assets were denominated in foreign currencies. We may experience losses resulting from fluctuations in the values of non-U.S. currencies, which could adversely impact our results of operations and financial condition. Refer to “Quantitative and Qualitative Disclosures about Market Risk – Foreign currency exchange rate risk”, under Item 7A.

Regulatory and Other Governmental Developments

The regulatory regimes under which we operate, and potential changes thereto, could have an adverse effect on our business.

Our insurance and reinsurance subsidiaries conduct business globally including in all 50 states of the United States. Our businesses in each of these jurisdictions are subject to varying degrees of regulation and supervision. The laws and regulations of the jurisdictions in which our insurance and reinsurance subsidiaries are domiciled require, among other things, that these subsidiaries maintain minimum levels of statutory capital, surplus and liquidity, meet solvency standards and submit to periodic examinations of their financial condition. These laws and regulations also sometimes restrict payments of dividends and reductions of capital. These statutes, regulations and policies may also restrict the ability of these subsidiaries to write insurance and reinsurance policies, to make certain investments and to distribute funds. The purpose of insurance laws and regulations generally is to protect insureds and ceding insurance companies, not our shareholders. We may not be able to comply fully with, or obtain appropriate exemptions from, these statutes and regulations. Failure to comply with or to obtain appropriate authorizations and/or exemptions under any applicable laws could result in restrictions on our ability to do business or undertake activities that are regulated in one or more of the jurisdictions in which we conduct business and could subject us to fines and other sanctions. In addition, changes in the laws or regulations to which our insurance and reinsurance subsidiaries are subject could have an adverse effect on our business.

Current legal and regulatory activities relating to insurance brokers and agents, contingent commissions and certain finite-risk insurance products could adversely affect our business, results of operations and financial condition.

As described in greater detail in Note 12 to our Consolidated Financial Statements, ACE has received numerous regulatory inquiries, subpoenas, interrogatories, and civil investigative demands from regulatory authorities in connection with pending investigations of insurance industry practices. ACE is cooperating and will continue to cooperate with such inquiries. We cannot assure you that we will not receive any additional requests for information or subpoenas or what actions, if any, any of these governmental agencies will take as a result of these investigations. Additionally, at this time, we are unable to predict the potential effects, if any, that these actions may have upon the insurance and reinsurance markets and industry business practices or what, if any, changes may be made to laws and regulations regarding the industry and financial reporting. Any of the foregoing could adversely affect our business, results of operations and financial condition.

Events may result in political, regulatory and industry initiatives, which could adversely affect our business.

Government intervention has occurred in the insurance and reinsurance markets in relation to terrorism coverage both in the U.S. and through industry initiatives in other countries. TRIA, which was enacted to ensure the availability of insurance coverage for certain types of terrorist acts in the U.S., will expire on December 31, 2007 and there can be no assurance that it will be extended beyond that date or as to the terms of any such extension. Refer to “Regulation – U.S. Operations” for more information.

Government intervention and the possibility of future interventions have created uncertainty in the insurance and reinsurance markets about the definition of terrorist acts and the extent to which future coverages will extend to terrorist acts. Government regulators are generally concerned with the protection of policyholders to the exclusion of

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other constituencies, including shareholders of insurers and reinsurers. While we cannot predict the exact nature, timing or scope of possible governmental initiatives, such proposals could adversely affect our business by:

• providing insurance and reinsurance capacity in markets and to consumers that we target;

• requiring our participation in industry pools and guaranty associations;

• expanding the scope of coverage under existing policies;

• regulating the terms of insurance and reinsurance policies; or

• disproportionately benefiting the companies of one country over those of another.

The insurance industry is also affected by political, judicial and legal developments that may create new and expanded theories of liability. Such changes may result in delays or cancellations of products and services by insurers and reinsurers, which could adversely affect our business.

Company Structure

Our ability to pay dividends and to make payments on indebtedness may be constrained by our holding company structure.

ACE Limited is a holding company and does not have any significant operations or assets other than its ownership of the shares of its operating insurance and reinsurance subsidiaries. Dividends and other permitted distributions from our insurance subsidiaries are our primary source of funds to meet ongoing cash requirements, including any future debt service payments and other expenses, and to pay dividends to our shareholders. Some of our insurance subsidiaries are subject to significant regulatory restrictions limiting their ability to declare and pay dividends. The inability of our insurance subsidiaries to pay dividends in an amount sufficient to enable us to meet our cash requirements at the holding company level could have an adverse effect on our operations and our ability to pay dividends to our shareholders and/or meet our debt service obligations.

ACE Limited is a Cayman Islands company with headquarters in Bermuda; it may be difficult for you to enforce judgments against it or its directors and executive officers.

ACE Limited is incorporated pursuant to the laws of the Cayman Islands and our principal executive offices are located in Bermuda. In addition, certain of our directors and officers reside outside the United States, and all or a substantial portion of our assets and the assets of such persons are located in jurisdictions outside the United States. As such, it may be difficult or impossible to affect service of process within the United States upon those persons or to recover against us or them on judgments of U.S. courts, including judgments predicated upon civil liability provisions of the U.S. federal securities laws.

ACE has been advised by Maples and Calder, its Cayman Islands counsel, that there is doubt as to whether the courts of the Cayman Islands would enforce:

• judgments of U.S. courts based upon the civil liability provisions of the U.S. Federal securities laws obtained in actions against ACE or its directors and officers, who reside outside the United States; or

• original actions brought in the Cayman Islands against these persons or ACE predicated solely upon U.S. Federal securities laws.

ACE has also been advised by Maples and Calder that there is no treaty in effect between the United States and the Cayman Islands providing for this enforcement, and there are grounds upon which Cayman Islands courts may not enforce judgments of United States courts. Some remedies available under the laws of United States jurisdictions, including some remedies available under the U.S. Federal securities laws, would not be allowed in Cayman Islands courts as these could be contrary to that nation’s public policy.

Insurance and Reinsurance Industry

Competition in the insurance industry could reduce our margins.

The insurance and reinsurance industry is highly competitive. We compete on an international and regional basis with major U.S., Bermuda, European and other international insurers and reinsurers and with underwriting syndicates, some of which have greater financial, marketing and management resources than we do. We also compete with new companies that continue to be formed to enter the insurance and reinsurance markets. In addition, capital market participants have recently created alternative products that are intended to compete with reinsurance products.

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Increased competition could result in fewer submissions, lower premium rates and less favorable policy terms and conditions, which could reduce our margins.

The insurance and reinsurance business is historically cyclical, and we expect to experience periods with excess underwriting capacity and unfavorable premium rates.

The insurance and reinsurance business historically has been a cyclical industry characterized by periods of intense price competition due to excessive underwriting capacity as well as periods when shortages of capacity permitted favorable premium levels. An increase in premium levels is often offset by an increasing supply of insurance and reinsurance capacity, either by capital provided by new entrants or by the commitment of additional capital by existing insurers or reinsurers, which may cause prices to decrease. Any of these factors could lead to a significant reduction in premium rates, less favorable policy terms and fewer submissions for our underwriting services. In addition to these considerations, changes in the frequency and severity of losses suffered by insureds and insurers may affect the cycles of the insurance and reinsurance business significantly.

Charter Documents and Applicable Law

There are provisions in our charter documents that may reduce or increase the voting rights of our Ordinary Shares.

Our Articles of Association generally provide that shareholders have one vote for each ordinary share held by them and are entitled to vote, on a non-cumulative basis, at all meetings of shareholders. However, the voting rights exercisable by a shareholder may be limited so that certain persons or groups are not deemed to hold 10 percent or more of the voting power conferred by our Ordinary Shares. Under these provisions, some shareholders may have the right to exercise their voting rights limited to less than one vote per share. Moreover, these provisions could have the effect of reducing the voting power of some shareholders who would not otherwise be subject to the limitation by virtue of their direct share ownership. In addition, our Board of Directors may limit a shareholder’s exercise of voting rights where it deems it necessary to do so to avoid adverse tax, legal or regulatory consequences.

We also have the authority under our Articles of Association to request information from any shareholder for the purpose of determining whether a shareholder’s voting rights are to be limited pursuant to our Articles of Association. If a shareholder fails to respond to our request for information or submits incomplete or inaccurate information in response to a request by us, we may, in our sole discretion, eliminate the shareholder’s voting rights.

There are provisions in our Articles of Association which may restrict the ability to transfer Ordinary Shares and which may require shareholders to sell their Ordinary Shares.

Our Board of Directors may decline to register a transfer of any Ordinary Shares under some circumstances, including if they have reason to believe that any non-de minimis adverse tax, regulatory or legal consequences to us, any of our subsidiaries or any of our shareholders may occur as a result of such transfer. Our Articles of Association also provide that if our Board of Directors determines that share ownership by a person may result in non-de minimis adverse tax, legal or regulatory consequences to us, any of our subsidiaries or any of our shareholders, then we have the option, but not the obligation, to require that shareholder to sell to us or to third parties to whom we assign the repurchase right for fair market value the minimum number of Ordinary Shares held by such person which is necessary to eliminate the non-de minimis adverse tax, legal or regulatory consequences.

Applicable laws may make it difficult to effect a change of control of our company.

Before a person can acquire control of a U.S. insurance company, prior written approval must be obtained from the insurance commissioner of the state where the domestic insurer is domiciled. Prior to granting approval of an application to acquire control of a domestic insurer, the state insurance commissioner will consider such factors as the financial strength of the applicant, the integrity and management of the applicant’s Board of Directors and executive officers, the acquiror’s plans for the future operations of the domestic insurer and any anti-competitive results that may arise from the consummation of the acquisition of control. Generally, state statutes provide that control over a domestic insurer is presumed to exist if any person, directly or indirectly, owns, controls, holds with the power to vote, or holds proxies representing, ten percent or more of the voting securities of the domestic insurer. Because a person acquiring ten percent or more of our Ordinary Shares would indirectly control the same percentage of the stock of our U.S. insurance subsidiaries, the insurance change of control laws of various U.S. jurisdictions would likely apply to such a transaction.

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We and certain of our U.K. subsidiaries are subject to the regulatory jurisdiction of the Council of Lloyd’s. Lloyd’s imposes an absolute prohibition on any person being a ten percent controller of a corporate member without first notifying Lloyd’s and receiving their consent. Because a person acquiring ten percent or more of our Ordinary Shares would indirectly control the same percentage of the stock of our subsidiary that is a Lloyd’s corporate member, the Lloyd’s restrictions on becoming a controller of a corporate member would likely apply to such a transaction.

Laws of other jurisdictions in which one or more of our existing subsidiaries are, or a future subsidiary may be, organized or domiciled may contain similar restrictions on the acquisition of control of ACE.

While our Articles of Association limit the voting power of any shareholder to less than ten percent, there can be no assurance that the applicable regulatory body would agree that a shareholder who owned ten percent or more of our Ordinary Shares did not, because of the limitation on the voting power of such shares, control the applicable insurance subsidiary.

These laws may discourage potential acquisition proposals and may delay, deter or prevent a change of control of the Company, including transactions that some or all of our shareholders might consider to be desirable.

U.S. persons who own our Ordinary Shares may have more difficulty in protecting their interests than U.S. persons who are shareholders of a U.S. corporation.

The Companies Law (2004 Revision), of the Cayman Islands which applies to us, differs in certain material respects from laws generally applicable to U.S. corporations and their shareholders. These differences include the manner in which directors must disclose transactions in which they have an interest, the rights of shareholders to bring class action and derivative lawsuits and the scope of indemnification available to directors and officers.

Anti-takeover provisions in our charter documents could impede an attempt to replace our directors or to effect a change of control, which could diminish the value of our Ordinary Shares.

Our Articles of Association contain provisions that may make it more difficult for shareholders to replace directors and could delay or prevent a change of control that a shareholder might consider favorable. These provisions include a staggered Board of Directors, limitations on the ability of shareholders to remove directors other than for cause, limitations on voting rights and restrictions on transfer of our Ordinary Shares. These provisions may prevent a shareholder from receiving the benefit from any premium over the market price of our Ordinary Shares offered by a bidder in a potential takeover. Even in the absence of an attempt to effect a change in management or a takeover attempt, these provisions may adversely affect the prevailing market price of our Ordinary Shares if they are viewed as discouraging takeover attempts in the future.

Taxation

We may become subject to taxes in Bermuda after March 28, 2016, which may have an adverse effect on our results of operations and your investment.

The Bermuda Minister of Finance, under the Exempted Undertakings Tax Protection Act 1966 of Bermuda, as amended, has given each of ACE Limited and its Bermuda insurance subsidiaries a written assurance that if any legislation is enacted in Bermuda that would impose tax computed on profits or income, or computed on any capital asset, gain or appreciation, or any tax in the nature of estate duty or inheritance tax, then the imposition of any such tax would not be applicable to those companies or any of their respective operations, shares, debentures or other obligations until March 28, 2016, except insofar as such tax would apply to persons ordinarily resident in Bermuda or is payable by us in respect of real property owned or leased by us in Bermuda. Given the limited duration of the Minister of Finance’s assurance, we cannot be certain that we will not be subject to any Bermuda tax after March 28, 2016.

We may become subject to taxes in the Cayman Islands after January 31, 2026, which may have an adverse effect on our results of operations and your investment.

Under current Cayman Islands law, we are not obligated to pay any taxes in the Cayman Islands on our income or gains. We have received an undertaking from the Governor in Cabinet of the Cayman Islands pursuant to the provisions of the Tax Concessions Law, as amended, that until January 31, 2026, (i) no subsequently enacted law imposing any tax on profits, income, gains or appreciation shall apply to us and (ii) no such tax and no tax in the nature of an estate duty or an inheritance tax shall be payable on any of our Ordinary Shares, debentures or other obligations. Under current law, no tax will be payable on the transfer or other disposition of our Ordinary Shares. The Cayman

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Islands currently impose stamp duties on certain categories of documents; however, our current operations do not involve the payment of stamp duties in any material amount. The Cayman Islands also currently impose an annual corporate fee upon all exempted companies incorporated in the Cayman Islands. Given the limited duration of the undertaking from the Governor in Cabinet of the Cayman Islands, we cannot be certain that we will not be subject to any Cayman Islands tax after January 31, 2026.

ACE Limited and our Bermuda-based subsidiaries may become subject to U.S. tax, which may have an adverse effect on our results of operations and your investment.

ACE Limited, ACE Bermuda Insurance Ltd., ACE Tempest Life Reinsurance Ltd. and our other Bermuda-based insurance subsidiaries operate in a manner so that none of these companies should be subject to U.S. tax (other than U.S. excise tax on insurance and reinsurance premium income attributable to insuring or reinsuring U.S. risks and U.S. withholding tax on some types of U.S. source investment income), because none of these companies should be treated as engaged in a trade or business within the United States. However, because there is considerable uncertainty as to the activities that constitute being engaged in a trade or business within the United States, we cannot be certain that the Internal Revenue Service (IRS) will not contend successfully that any of ACE Limited or its Bermuda-based subsidiaries is/are engaged in a trade or business in the United States. If ACE Limited or any of its Bermuda-based subsidiaries were considered to be engaged in a trade or business in the United States, such entity could be subject to U.S. corporate income and additional branch profits taxes on the portion of its earnings effectively connected to such U.S. business, in which case its results of operations and your investment could be adversely affected.

If you acquire ten percent or more of ACE Limited’s shares, you may be subject to taxation under the “controlled foreign corporation” (the CFC) rules.

Under certain circumstances, a U.S. person who owns ten percent or more of the voting power of a foreign corporation that is a CFC (a foreign corporation in which ten percent U.S. shareholders own more than 50 percent of the voting power of a foreign corporation or more than 25 percent of a foreign insurance company) for an uninterrupted period of 30 days or more during a taxable year must include in gross income for U.S. federal income tax purposes such “10 percent U.S. Shareholder’s” pro rata share of the CFC’s “subpart F income,” even if the subpart F income is not distributed to such 10 percent U.S. Shareholder if such 10 percent U.S. Shareholder owns (directly or indirectly through foreign entities) any of our shares on the last day of our fiscal year. “Subpart F income” of a foreign insurance corporation typically includes foreign personal holding company income (such as interest, dividends and other types of passive income), as well as insurance and reinsurance income (including underwriting and investment income) attributable to the insurance of risks situated outside the CFC’s country of incorporation.

We believe that because of the dispersion of our share ownership, provisions in our organizational documents that limit voting power and other factors, no U.S. person or U.S. Partnership who acquires shares of ACE Limited directly or indirectly through one or more foreign entities should be required to include our “subpart F income” in income under the CFC rules of the Code. It is possible, however, that the IRS could challenge the effectiveness of these provisions and that a court could sustain such a challenge, in which case your investment could be adversely affected if you own ten percent or more of ACE Limited’s stock.

U.S. persons who hold shares may be subject to U.S. federal income taxation at ordinary income rates on their proportionate share of our Related Person Insurance Income (RPII).

If the RPII of any of our non-U.S. insurance subsidiaries (each a “Non-U.S. Insurance Subsidiary”) were to equal or exceed 20 percent of that company’s gross insurance income in any taxable year and direct or indirect insureds (and persons related to those insureds) own directly or indirectly through foreign entities 20 percent or more of the voting power or value of ACE Limited, then a U.S. person who owns any shares of ACE Limited (directly or indirectly through foreign entities) on the last day of the taxable year would be required to include in its income for U.S. federal income tax purposes such person’s pro rata share of such company’s RPII for the entire taxable year, determined as if such RPII were distributed proportionately only to U.S. persons at that date regardless of whether such income is distributed. In addition, any RPII that is includible in the income of a U.S. tax-exempt organization may be treated as unrelated business taxable income. We believe that the gross RPII of each Non-U.S. Insurance Subsidiary did not in prior years of operation and is not expected in the foreseeable future to equal or exceed 20 percent of each such company’s gross insurance income, and we do not expect the direct or indirect insureds of each Non-U.S. Insurance Subsidiary (and persons related to such insureds) to directly or indirectly own 20 percent or more of either the voting power or value of

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our shares, but we cannot be certain that this will be the case because some of the factors which determine the extent of RPII may be beyond our control. If these thresholds are met or exceeded, and if you are an affected U.S. person, your investment could be adversely affected.

U.S. persons who hold shares will be subject to adverse tax consequences if we are considered to be a Passive Foreign Investment Company (PFIC) for U.S. federal income tax purposes.

If ACE Limited is considered a PFIC for U.S. federal income tax purposes, a U.S. person who owns any shares of ACE Limited will be subject to adverse tax consequences, including subjecting the investor to a greater tax liability than might otherwise apply and subjecting the investor to tax on amounts in advance of when tax would otherwise be imposed, in which case your investment could be adversely affected. In addition, if ACE Limited were considered a PFIC, upon the death of any U.S. individual owning shares, such individual’s heirs or estate would not be entitled to a “step-up” in the basis of the shares which might otherwise be available under U.S. federal income tax laws. We believe that we are not, have not been, and currently do not expect to become, a PFIC for U.S. federal income tax purposes. We cannot assure you, however, that we will not be deemed a PFIC by the IRS. If we were considered a PFIC, it could have adverse tax consequences for an investor that is subject to U.S. federal income taxation. There are currently no regulations regarding the application of the PFIC provisions to an insurance company. New regulations or pronouncements interpreting or clarifying these rules may be forthcoming. We cannot predict what impact, if any, such guidance would have on an investor that is subject to U.S. federal income taxation.

U.S. tax-exempt organizations who own our shares may recognize unrelated business taxable income.

A U.S. tax-exempt organization may recognize unrelated business taxable income if a portion of our insurance income is allocated to the organization, which generally would be the case if either we are a CFC and the tax-exempt shareholder is a ten percent U.S. Shareholder or there is RPII, certain exceptions do not apply and the tax-exempt organization, directly or indirectly through foreign entities, owns any shares of ACE Limited. Although we do not believe that any U.S. persons or U.S. Partnerships should be allocated such insurance income, we cannot be certain that this will be the case. Potential U.S. tax-exempt investors are advised to consult their tax advisors.

Changes in U.S. federal income tax law could adversely affect an investment in our shares.

Legislation is periodically introduced in the U.S. Congress intended to eliminate some perceived tax advantages of companies (including insurance companies) that have legal domiciles outside the United States but have certain U.S. connections. While there are no currently pending legislative proposals which, if enacted, would have a material adverse effect on us or our shareholders, it is possible that legislative proposals could emerge in the future that could have an adverse impact on us or our shareholders.

The Organization for Economic Cooperation and Development and the European Union are considering measures that might encourage countries to increase our taxes.

A number of multilateral organizations, including the European Union, the Organization for Economic Cooperation and Development (OECD), the Financial Action Task Force and the Financial Stability Forum (FSF) have, in recent years, identified some countries as not participating in adequate information exchange, engaging in harmful tax practices or not maintaining adequate controls to prevent corruption, such as money laundering activities. Recommendations to limit such harmful practices are under consideration by these organizations, and a report published on November 27, 2001 by the OECD at the behest of FSF titled “Behind the Corporate Veil: Using Corporate Entities for Illicit Purposes,” contains an extensive discussion of specific recommendations. The OECD has threatened non-member jurisdictions that do not agree to cooperate with the OECD with punitive sanctions by OECD member countries, though specific sanctions have yet to be adopted by OECD member countries. It is as yet unclear what these sanctions will be, who will adopt them and when or if they will be imposed. In an April 18, 2002 report, updated as of June 2004, Bermuda was not listed as an uncooperative tax haven jurisdiction by the OECD because it previously committed to eliminate harmful tax practices and to embrace international tax standards for transparency, exchange of information, and the elimination of regimes for financial and other services that attract businesses with no substantial domestic activity. We cannot assure you, however, that the action taken by Bermuda would be sufficient to preclude all effects of the measures or sanctions described above, which, if ultimately adopted, could adversely affect Bermuda companies such as us.

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There are currently no unresolved SEC staff comments regarding our periodic or current reports.