ITEM 1.    BUSINESS

         We refer you to Item 1A "Risk Factors" for a discussion of risk factors relating to our business.

OUR COMPANY

General

        Arch Capital Group Ltd. ("ACGL" and, together with its subsidiaries, the "Company," "we," or "us") is a Bermuda public limited liability company with over $3.8 billion in capital at December 31, 2008 and, through operations in Bermuda, the United States, Europe and Canada, writes insurance and reinsurance on a worldwide basis. While we are positioned to provide a full range of property and casualty insurance and reinsurance lines, we focus on writing specialty lines of insurance and reinsurance.

        We launched an underwriting initiative in October 2001 to meet current and future demand in the global insurance and reinsurance markets. Since that time, we have attracted a proven management team with extensive industry experience and enhanced our existing global underwriting platform for our insurance and reinsurance businesses. It is our belief that our underwriting platform, our experienced management team and our strong capital base that is unencumbered by significant pre-2002 risks have enabled us to establish a strong presence in the insurance and reinsurance markets. For 2008, our seventh full year of operation, we wrote $2.8 billion of net premiums, reported net income available to common shareholders of $265.1 million and earned a return on average equity of 7.8%. Diluted book value per share was $51.36 at December 31, 2008, compared to $55.12 per share at December 31, 2007.

        ACGL's registered office is located at Clarendon House, 2 Church Street, Hamilton HM 11, Bermuda (telephone number: (441) 295-1422), and its principal executive offices are located at Wessex House, 45 Reid Street, Hamilton HM 12, Bermuda (telephone number: (441) 278-9250). ACGL makes available free of charge through its website, located at http://www.archcapgroup.bm , its annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and all amendments to those reports as soon as reasonably practicable after such material is electronically filed with, or furnished to, the SEC. The public may read and copy any materials ACGL files with the SEC at the SEC's Public Reference Room at 100 F Street, NE, Washington, D.C. 20549. The public may obtain information on the operation of the Public Reference Room by calling 1-800-SEC-0330. The SEC also maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC (such as ACGL) and the address of that site is http://www.sec.gov .

Our History

        ACGL was formed in September 2000 and became the sole shareholder of Arch Capital Group (U.S.) Inc. ("Arch-U.S.") pursuant to an internal reorganization transaction completed in November 2000, as described below. Arch-U.S. is a Delaware company formed in March 1995 under the original name of "Risk Capital Holdings, Inc.," which commenced operations in September 1995 following the completion of an initial public offering. From that time until May 2000, Arch-U.S. provided reinsurance and other forms of capital for insurance companies through its wholly owned subsidiary, Arch Reinsurance Company ("Arch Re U.S."), a Nebraska corporation formed in 1995 under the original name of "Risk Capital Reinsurance Company."

        On May 5, 2000, Arch-U.S. sold the prior reinsurance operations of Arch Re U.S. to White Mountains Reinsurance Company of America ("WTM Re"), formerly known as Folksamerica Reinsurance Company, in an asset sale, but retained its surplus and U.S.-licensed reinsurance platform. The sale was precipitated by, among other things, losses on the reinsurance business of Arch Re U.S.

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and increasing competition, which had been adversely affecting the results of operations and financial condition of Arch Re U.S. The WTM Re transaction, which resulted from extensive arm's length negotiation, was structured as a transfer and assumption agreement (and not as reinsurance) and, accordingly, the loss reserves (and any related reinsurance recoverables) related to the transferred business are not included in the balance sheet of Arch Re U.S. However, in the event that WTM Re refuses or is unable to make payment of claims on the reinsurance business assumed by it in the May 2000 sale and the notice given to reinsureds is found not to be an effective release by such reinsureds, Arch Re U.S. would be liable for such claims. In addition, Arch Re U.S. retained all liabilities not assumed by WTM Re, including all liabilities not arising under reinsurance agreements transferred to WTM Re in the asset sale. On November 8, 2000, following the approval by Arch-U.S.'s shareholders, Arch-U.S. completed an internal reorganization that resulted in Arch-U.S. becoming a wholly owned subsidiary of ACGL.

        During the period from May 2000 through the announcement of our underwriting initiative in October 2001, we built and acquired insurance businesses that were intended to enable us to generate both fee-based revenue (e.g., commissions and advisory and management fees) and risk-based revenue (i.e., insurance premium). As part of this strategy, we built an underwriting platform that was intended to enable us to maximize risk-based revenue during periods in the underwriting cycle when we believed it was more favorable to assume underwriting risk. In October 2001, we concluded that underwriting conditions favored dedicating our attention exclusively to building our insurance and reinsurance businesses.

        The development of our underwriting platform included the following steps: (1) after the completion of the WTM Re asset sale, we retained our U.S.-licensed reinsurer, Arch Re U.S., and Arch Excess & Surplus Insurance Company ("Arch E&S"), currently an approved excess and surplus lines insurer in 47 states and the District of Columbia and an admitted insurer in one state; (2) in May 2001, we formed Arch Reinsurance Ltd. ("Arch Re Bermuda"), our Bermuda-based reinsurance and insurance subsidiary; (3) in June 2001, we acquired Arch Risk Transfer Services Ltd., which included Arch Insurance Company ("Arch Insurance"), currently an admitted insurer in 50 states, the District of Columbia, Puerto Rico, the U.S. Virgin Islands and Guam with a branch office in Canada, and rent-a-captive and other facilities that provide insurance and alternative risk transfer services; (4) in February 2002, we acquired Arch Specialty Insurance Company ("Arch Specialty"), currently an approved excess and surplus lines insurer in 49 states, the District of Columbia, Puerto Rico and the U.S. Virgin Islands and an admitted insurer in one state; (5) in June 2003, we acquired Arch Indemnity Insurance Company (formerly known as Western Diversified Casualty Insurance Company) ("Arch Indemnity"), an admitted insurer in 49 states and the District of Columbia; (6) in May 2004, our London-based subsidiary, Arch Insurance Company (Europe) Limited ("Arch Insurance Europe"), was approved by the Financial Services Authority in the U.K. to commence insurance underwriting activities and began writing a range of specialty commercial lines in Europe and the U.K. during the 2004 third quarter; (7) in January 2005, Arch Insurance received its federal license to commence underwriting in Canada and began writing business in the first quarter of 2005; and (8) in November 2006, Arch Reinsurance Ltd., Hamilton (Bermuda), European Branch Zurich ("Arch Re Bermuda Swiss Branch"), the Swiss branch of Arch Re Bermuda, was registered with the commercial register of the Canton of Zurich to commence reinsurance underwriting activities in Switzerland. All liabilities arising out of the business of Arch Specialty and Arch Indemnity prior to the closing of our acquisitions of such companies were reinsured and guaranteed by the respective sellers, Sentry Insurance a Mutual Company ("Sentry") and Protective Life Corporation and certain of its affiliates.

        In 2007, we (1) formed Arch Re Accident & Health ApS ("Arch Re Denmark"), a Danish underwriting agency which conducts accident and health underwriting as a branch office of Arch Reinsurance Europe Underwriting Limited ("Arch Re Europe"), which was formed in 2008 and is described below; (2) acquired the assets of Wexford Underwriting Managers, Inc. ("Wexford"), a

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managing general agent, to write excess workers' compensation and employers' liability insurance, a new line of business for us at the time; and (3) launched our property facultative reinsurance underwriting operations which are headquartered in Farmington, Connecticut. On January 22, 2008, Arch Re Bermuda and Gulf Investment Corporation GSC ("GIC") entered into a joint venture agreement for the purpose of forming a reinsurance company in the Dubai International Financial Centre. GIC is owned equally by the six member states of the Gulf Cooperation Council ("GCC"), which include Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates. In May 2008, we provided $100.0 million of funding to Gulf Reinsurance Limited ("Gulf Re"), a newly formed reinsurer based in the Dubai International Financial Centre, pursuant to the joint venture agreement with GIC. Gulf Re provides property and casualty reinsurance primarily in those member states of the GCC.

        In 2008, we expanded our underwriting platform through the formation of Arch Re Europe, an Irish company based in Dublin which was authorized by the Irish Financial Services Regulatory Authority in October 2008 to underwrite reinsurance. The operations of Arch Re Bermuda Swiss Branch were transferred to the newly formed Swiss branch of Arch Re Europe called Arch Reinsurance Europe Underwriting Limited, Dublin (Ireland), Zurich Branch ("Arch Re Europe Swiss Branch"). Arch Re Europe Swiss Branch commenced underwriting from the date of transfer. Arch Re Bermuda Swiss Branch was de-registered as a branch in early 2009. In addition, in the first quarter of 2009, we received approval in principle from the Lloyd's Franchise Board and the Financial Services Authority in the United Kingdom to establish a managing agent and syndicate at Lloyd's. The newly formed Syndicate 2012 is expected to commence underwriting in the second quarter of 2009.

        The growth of our insurance and reinsurance platforms was supported through the net proceeds of: (1) an equity capital infusion of $763.2 million led by funds affiliated with Warburg Pincus LLC ("Warburg Pincus funds") and Hellman & Friedman LLC ("Hellman & Friedman funds") in late 2001; (2) a public offering of 7,475,000 of our common shares with net proceeds of $179.2 million in April 2002; (3) the exercise of class A warrants by our principal shareholders and other investors in September 2002, which provided net proceeds of $74.3 million; (4) a March 2004 public offering of 4,688,750 of our common shares with net proceeds of $179.3 million; (5) a May 2004 public offering of $300.0 million principal amount of our 7.35% senior notes due May 2034 with net proceeds of $296.4 million, of which $200.0 million was used to repay all amounts outstanding under our existing credit facility; (6) a February 2006 public offering of $200.0 million of our 8.00% series A non-cumulative preferred shares with a liquidation preference of $25.00 per share with net proceeds of $193.5 million; and (7) a May 2006 public offering $125.0 million of our 7.875% series B non-cumulative preferred shares with a liquidation preference of $25.00 per share with net proceeds of $120.9 million.

        The board of directors of ACGL authorized the investment of up to $1.5 billion in ACGL's common shares through a share repurchase program. Such amount consisted of a $1.0 billion authorization in February 2007 and a $500.0 million authorization in May 2008. Repurchases under the program may be effected from time to time in open market or privately negotiated transactions through February 2010. Since the inception of the share repurchase program, ACGL has repurchased approximately 15.3 million common shares for an aggregate purchase price of $1.05 billion. The timing and amount of the repurchase transactions under this program will depend on a variety of factors, including market conditions and corporate and regulatory considerations. In connection with the repurchase program, the Warburg Pincus funds waived their rights relating to share repurchases under their shareholders agreement with ACGL for all repurchases of common shares by ACGL under the repurchase program in open market transactions and certain privately negotiated transactions. In May 2007, the Hellman & Friedman funds ceased to own shares of ACGL and their rights under the shareholders agreement with ACGL terminated.

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Operations

        We classify our businesses into two underwriting segments, insurance and reinsurance. For an analysis of our underwriting results by segment, see note 3, "Segment Information," of the notes accompanying our consolidated financial statements and "Management's Discussion and Analysis of Financial Condition and Results of Operations—Results of Operations."

Our Insurance Operations

        Our insurance operations are conducted in Bermuda, the United States, Europe and Canada. Our insurance operations in Bermuda are conducted through Arch Insurance (Bermuda), a division of Arch Re Bermuda, which has an office in Hamilton, Bermuda. In the U.S., our insurance group's principal insurance subsidiaries are Arch Insurance, Arch E&S, Arch Specialty and Arch Indemnity. The headquarters for our insurance group's U.S. support operations (excluding underwriting units) relocated from New York City to Jersey City, New Jersey during the first quarter of 2009. The insurance group has additional offices throughout the U.S., including four regional offices located in: Alpharetta, Georgia; Chicago, Illinois; New York, New York; and San Francisco, California. In addition, Arch Insurance has a branch office in Toronto, Canada. Our insurance group's European operations are conducted through Arch Insurance Europe, based in London, which also has branches in Germany, Italy, Spain, Denmark and Sweden. In the first quarter of 2009, we received approval in principle from the Lloyd's Franchise Board and the Financial Services Authority in the United Kingdom to establish a managing agent and syndicate at Lloyd's. The syndicate will enhance our underwriting platform by providing us with access to Lloyd's extensive distribution network and worldwide licenses. The newly formed Syndicate 2012 is expected to commence underwriting in the second quarter of 2009. Syndicate 2012 will be managed by its managing agent, Arch Underwriting Lloyd's Ltd, based in the London office of Arch Insurance Europe. As of February 15, 2009, our insurance group had approximately 990 employees.

        Strategy.     Our insurance group's strategy is to operate in lines of business in which underwriting expertise can make a meaningful difference in operating results. The insurance group focuses on talent-intensive rather than labor-intensive business and seeks to operate profitably (on both a gross and net basis) across all of its product lines. To achieve these objectives, our insurance group's operating principles are to:

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Capitalize on Profitable Underwriting Opportunities.   Our insurance group believes that its experienced management and underwriting teams are positioned to locate and identify business with attractive risk/reward characteristics. As profitable underwriting opportunities are identified, our insurance group will continue to seek to make additions to their product portfolio in order to take advantage of market trends. This may include adding underwriting and other professionals with specific expertise in specialty lines of insurance.



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Centralize Responsibility for Underwriting.   Our insurance group consists of a range of product lines. The underwriting executive in charge of each product line oversees all aspects of the underwriting product development process within such product line. Our insurance group believes that centralizing the control of such product line with the respective underwriting executive allows for close management of underwriting and creates clear accountability for results. Our U.S. insurance group has four regional offices, and the executive in charge of each region is primarily responsible for all aspects of the marketing and distribution of our insurance group's products, including the management of broker and other producer relationships in such executive's respective region. In our non-U.S. offices, a similar philosophy is observed, with responsibility for the management of each product line residing with the senior underwriting executive in charge of such product line.

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Maintain a Disciplined Underwriting Philosophy.   Our insurance group's underwriting philosophy is to generate an underwriting profit through prudent risk selection and proper pricing. Our insurance group believes that the key to this approach is adherence to uniform underwriting standards across all types of business. Our insurance group's senior management closely monitors the underwriting process.



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Focus on Providing Superior Claims Management.   Our insurance group believes that claims handling is an integral component of credibility in the market for insurance products. Therefore, our insurance group believes that its ability to handle claims expeditiously and satisfactorily is a key to its success. Our insurance group employs experienced claims professionals and also utilizes experienced external claims managers (third party administrators) where appropriate.



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Utilize a Brokerage Distribution System.   Our insurance group believes that by utilizing a brokerage distribution system, consisting of select international, national and regional brokers, both wholesale and retail, it can efficiently access a broad customer base while maintaining underwriting control and discipline.

        Our insurance group writes business on both an admitted and non-admitted basis. Our insurance group focuses on the following areas:

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Casualty.   Our insurance group's casualty unit writes primary and excess casualty insurance coverages, including railroad and middle market energy business.



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Construction and National Accounts.   Our insurance group's construction unit provides primary and excess casualty coverages to middle and large accounts in the construction industry. The construction unit also provides coverage for environmental and design professionals, including policies for architectural and engineering firms and construction projects, pollution legal liability coverage for fixed sites, and alternative markets business, including captive insurance programs. Our insurance group's national accounts casualty unit provides a wide range of products for middle and large accounts and specializes in loss sensitive primary casualty insurance programs, including large deductible, self-insured retention and retrospectively rated programs.



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Executive Assurance.   Our insurance group's executive assurance unit focuses on directors' and officers' liability insurance coverages for corporate and financial institution clients. This unit also writes financial institution errors and omissions coverages, employment practices liability insurance, pension trust errors and omissions/fiduciary liability insurance and fidelity bonds.



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Healthcare.   Our insurance group's healthcare unit provides medical professional and general liability insurance coverages for the healthcare industry, including excess professional liability programs for large, integrated hospital systems, outpatient facilities, clinics and long-term care facilities.



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Professional Liability.   Our insurance group's professional liability unit has the following principal areas of focus: (i) large law firms and accounting firms and professional programs; and (ii) miscellaneous professional liability, including coverages for consultants, network security, securities broker-dealers, wholesalers, captive agents and managing general agents.



•

Programs.   Our insurance group's programs unit targets program managers with unique expertise and niche products offering general liability, commercial automobile, inland marine and non-catastrophe-exposed property business. This unit offers primarily package policies, underwriting workers' compensation and umbrella liability business in support of desirable package programs.



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Property, Marine and Aviation (including Special Risks).   Our insurance group's property unit provides primary and excess general property insurance coverages, including catastrophe-exposed property coverage, for commercial clients. The special risks unit provides onshore and offshore

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property insurance coverages for commercial clients primarily in the energy industry. The special risks unit also provides contractors all risk, erection all risk, aerospace (consisting of aviation and satellite risks) and stand alone terrorism insurance coverage for commercial clients.

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Surety.   Our insurance group's surety unit provides contract surety coverages, including contract bonds (payment and performance bonds) for mid-size and large contractors and specialty contract bonds for homebuilders and developers.



•

Other.   Our insurance group also includes the following units: (i) excess workers compensation, which provides excess workers compensation and employers' liability insurance coverages for qualified self-insured groups, associations and trusts in a wide range of businesses; (ii) lender products, which provides collateral protection insurance coverages for financial institutions and specialty insurance coverage for automotive dealers; and (iii) travel and accident, which provides specialty travel and accident and related insurance products for individual and group travelers, as well as travel agents and suppliers.

        Underwriting Philosophy.     Our insurance group's underwriting philosophy is to generate an underwriting profit (on both a gross and net basis) through prudent risk selection and proper pricing across all types of business. One key to this philosophy is the adherence to uniform underwriting standards across each product line that focuses on the following:

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risk selection;



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desired attachment point;



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limits and retention management;



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due diligence, including financial condition, claims history, management, and product, class and territorial exposure;



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underwriting authority and appropriate approvals; and



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collaborative decision-making.

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        Premiums Written and Geographic Distribution.     Set forth below is summary information regarding net premiums written for our insurance group:

(1)

Includes excess workers' compensation and employers' liability business, lender products and travel and accident business.

        Marketing.     Our insurance group's products are marketed principally through a group of licensed independent retail and wholesale brokers. Clients (insureds) are referred to our insurance group through a large number of international, national and regional brokers and captive managers who receive from the insured or insurer a set fee or brokerage commission usually equal to a percentage of gross premiums. In the past, our insurance group also entered into contingent commission arrangements with some brokers that provide for the payment of additional commissions based on volume or profitability of business. In general, our insurance group has no implied or explicit commitments to accept business from any particular broker and, neither brokers nor any other third parties have the authority to bind our insurance group, except in the case where underwriting authority may be delegated contractually to selected program administrators. Such administrators are subject to a due diligence financial and operational review prior to any such delegation of authority and ongoing reviews and audits are carried out as deemed necessary by our insurance group to assure the continuing integrity of underwriting and related business operations. See "Risk Factors—Risks Relating to Our Company—We could be materially adversely affected to the extent that managing general agents, general agents and other producers in our program business exceed their underwriting authorities or

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otherwise breach obligations owed to us." For information on major brokers, see note 11, "Commitments and Contingencies—Concentrations of Credit Risk," of the notes accompanying our consolidated financial statements.

        Risk Management and Reinsurance.     In the normal course of business, our insurance group may cede a portion of its premium through quota share, surplus share, excess of loss and facultative reinsurance agreements. Reinsurance arrangements do not relieve our insurance group from its obligations to insureds. Reinsurance recoverables are recorded as assets, predicated on the reinsurers' ability to meet their obligations under the reinsurance agreements. If the reinsurers are unable to satisfy their obligations under the agreements, our insurance subsidiaries would be liable for such defaulted amounts. Our insurance subsidiaries, through their respective reinsurance security committees ("RSC"), are selective with regard to reinsurers, seeking to place reinsurance with only those reinsurers which meet and maintain specific standards of established criteria for financial strength. Each RSC evaluates the financial viability of its reinsurers through financial analysis, research and review of rating agencies' reports and also monitors reinsurance recoverables and letters of credit with unauthorized reinsurers. The financial analysis includes ongoing assessments of reinsurers, including a review of the financial stability, appropriate licensing, reputation, claims paying ability and underwriting philosophy of each reinsurer. Our insurance group will continue to evaluate its reinsurance requirements. See note 4, "Reinsurance," of the notes accompanying our consolidated financial statements.

        For catastrophe-exposed insurance business, our insurance group seeks to limit the amount of exposure to catastrophic losses it assumes through a combination of managing aggregate limits, underwriting guidelines and reinsurance. For a discussion of our risk management policies, see "Management's Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies, Estimates and Recent Accounting Pronouncements—Ceded Reinsurance" and "Risk Factors—Risks Relating to Our Industry—The failure of any of the loss limitation methods we employ could have a material adverse effect on our financial condition or results of operations."

        Claims Management.     Our insurance group's claims management function is performed by claims professionals, as well as experienced external claims managers (third party administrators), where appropriate. In addition to investigating, evaluating and resolving claims, members of our insurance group's claims departments work with underwriting professionals as functional teams in order to develop products and services desired by the group's customers.

Our Reinsurance Operations

        Our reinsurance operations are conducted on a worldwide basis through our reinsurance subsidiaries, Arch Re Bermuda, Arch Re U.S. and Arch Re Europe. Arch Re Bermuda has offices in Bermuda. Arch Re Bermuda's branch office in Switzerland transferred its operations to Arch Re Europe in the fourth quarter of 2008. However, Arch Re Bermuda retained the reinsurance business written by Arch Re Bermuda Swiss Branch from its opening in 2006 until the time its operations were transferred to Arch Re Europe Swiss Branch. In the first quarter of 2009, Arch Re Bermuda Swiss Branch was formally de-registered from the commercial register of the Canton of Zurich. Our newly-formed reinsurance company, Arch Re Europe, is headquartered in Dublin with a branch office in Zurich. Arch Re Europe commenced underwriting in the fourth quarter of 2008 to complement the existing property and casualty treaty capabilities within our reinsurance group. Arch Re U.S. operates out of its office in Morristown, New Jersey. Our property facultative reinsurance operations are primarily conducted through Arch Re U.S. with certain executive functions conducted through Arch Re Facultative Underwriters Inc. located in Farmington, Connecticut. Arch Re Denmark is a subsidiary of Arch Re Bermuda which underwrote travel and accident reinsurance on behalf of Arch Insurance Europe until the end of 2008. Commencing January 1, 2009, Arch Re Denmark started underwriting travel and accident reinsurance on behalf of Arch Re Europe. As of February 15, 2009, our reinsurance group had approximately 160 employees.

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        Strategy.     Our reinsurance group's strategy is to capitalize on our financial capacity, experienced management and operational flexibility to offer multiple products through our operations. The reinsurance group's operating principles are to:

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Actively Select and Manage Risks.   Our reinsurance group only underwrites business that meets certain profitability criteria, and it emphasizes disciplined underwriting over premium growth. To this end, our reinsurance group maintains centralized control over reinsurance underwriting guidelines and authorities.



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Maintain Flexibility and Respond to Changing Market Conditions.   Our reinsurance group's organizational structure and philosophy allows it to take advantage of increases or changes in demand or favorable pricing trends. Our reinsurance group believes that its existing Bermuda-, U.S.- and European-based platform, broad underwriting expertise and substantial capital facilitates adjustments to its mix of business geographically and by line and type of coverage. Our reinsurance group believes that this flexibility allows it to participate in those market opportunities that provide the greatest potential for underwriting profitability.



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Maintain a Low Cost Structure.   Our reinsurance group believes that maintaining tight control over its staffing level and operating primarily as a broker market reinsurer permits it to maintain low operating costs relative to its capital and premiums.

        Our reinsurance group writes business on both a proportional and non-proportional basis and writes both treaty and facultative business. In a proportional reinsurance arrangement (also known as pro rata reinsurance, quota share reinsurance or participating reinsurance), the reinsurer shares a proportional part of the original premiums and losses of the reinsured. The reinsurer pays the cedent a commission which is generally based on the cedent's cost of acquiring the business being reinsured (including commissions, premium taxes, assessments and miscellaneous administrative expenses) and may also include a profit factor. Non-proportional (or excess of loss) reinsurance indemnifies the reinsured against all or a specified portion of losses on underlying insurance policies in excess of a specified amount, which is called a "retention." Non-proportional business is written in layers and a reinsurer or group of reinsurers accepts a band of coverage up to a specified amount. The total coverage purchased by the cedent is referred to as a "program." Any liability exceeding the upper limit of the program reverts to the cedent.

        Our reinsurance group generally seeks to write significant lines on less commoditized classes of coverage, such as specialty property and casualty reinsurance treaties. However, with respect to other classes of coverage, such as property catastrophe and casualty clash, our reinsurance group participates in a relatively large number of treaties and assumes smaller lines where it believes that it can underwrite and process the business efficiently.

        Our reinsurance group focuses on the following areas:

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Casualty.   Our reinsurance group reinsures third party liability and workers' compensation exposures from ceding company clients primarily on a treaty basis. The exposures that it reinsures include, among others, directors' and officers' liability, professional liability, automobile liability, workers' compensation and excess and umbrella liability. Our reinsurance group writes this business on a proportional and non-proportional basis. On proportional and non-proportional "working casualty business," which is treated separately from casualty clash business, our reinsurance group prefers to write treaties where there is a meaningful amount of actuarial data and where loss activity is more predictable.



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Property Excluding Property Catastrophe.   Our treaty reinsurance group reinsures individual property risks of a ceding company. Property per risk treaty and pro rata reinsurance contracts written by our treaty reinsurance group cover claims from individual insurance policies issued by reinsureds and include both personal lines and commercial property exposures (principally

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covering buildings, structures, equipment and contents). The primary perils in this business include fire, explosion, collapse, riot, vandalism, wind, tornado, flood and earthquake.

Through our property facultative reinsurance group, we also write reinsurance on a facultative basis whereby the reinsurer assumes part of the risk under a single insurance contract. Facultative reinsurance is typically purchased by ceding companies for individual risks not covered by their reinsurance treaties, for unusual risks or for amounts in excess of the limits on their reinsurance treaties. Our property facultative reinsurance group focuses on commercial property risks on an excess of loss basis.

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Other Specialty.   Our reinsurance group writes other specialty lines, including non-standard automobile, surety, accident and health, workers' compensation catastrophe, trade credit and political risk.



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Property Catastrophe.   Our reinsurance group reinsures catastrophic perils for our reinsureds on a treaty basis. Treaties in this type of business provide protection for most catastrophic losses that are covered in the underlying policies written by our reinsureds. The primary perils in our reinsurance group's portfolio include hurricane, earthquake, flood, tornado, hail and fire. Our reinsurance group may also provide coverage for other perils on a case-by-case basis. Property catastrophe reinsurance provides coverage on an excess of loss basis when aggregate losses and loss adjustment expense from a single occurrence of a covered peril exceed the retention specified in the contract. The multiple claimant nature of property catastrophe reinsurance requires careful monitoring and control of cumulative aggregate exposure.



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Marine and Aviation.   Our reinsurance group writes marine business, which includes coverages for hull, cargo, transit and offshore oil and gas operations, and aviation business, which includes coverages for airline and general aviation risks. Business written may also include space business, which includes coverages for satellite assembly, launch and operation for commercial space programs.



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Other.   Our reinsurance group also writes non-traditional business, which is intended to provide insurers with risk management solutions that complement traditional reinsurance.

        Underwriting Philosophy.     Our reinsurance group employs a disciplined, analytical approach to underwriting reinsurance risks that is designed to specify an adequate premium for a given exposure commensurate with the amount of capital it anticipates placing at risk. A number of our reinsurance group's underwriters are also actuaries. It is our reinsurance group's belief that employing actuaries on the front-end of the underwriting process gives it an advantage in evaluating risks and constructing a high quality book of business.

        As part of the underwriting process, our reinsurance group typically assesses a variety of factors, including:

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adequacy of underlying rates for a specific class of business and territory;



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the reputation of the proposed cedent and the likelihood of establishing a long-term relationship with the cedent, the geographic area in which the cedent does business, together with its catastrophe exposures, and our aggregate exposures in that area;



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historical loss data for the cedent and, where available, for the industry as a whole in the relevant regions, in order to compare the cedent's historical loss experience to industry averages;



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projections of future loss frequency and severity; and



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the perceived financial strength of the cedent.

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        Premiums Written and Geographic Distribution.     Set forth below is summary information regarding net premiums written for our reinsurance group:

(1)

Includes professional liability, executive assurance and healthcare business.

(2)

Includes facultative business.

        Marketing.     Our reinsurance group markets its reinsurance products through brokers, except our property facultative reinsurance group, which generally deals directly with the ceding companies. Brokers do not have the authority to bind our reinsurance group with respect to reinsurance agreements, nor does our reinsurance group commit in advance to accept any portion of the business that brokers submit to them. Our reinsurance group generally pays brokerage fees to brokers based on negotiated percentages of the premiums written through such brokers. For information on major brokers, see note 11, "Commitments and Contingencies—Concentrations of Credit Risk," of the notes accompanying our consolidated financial statements.

        Risk Management and Retrocession.     Our reinsurance group currently purchases "common account" retrocessional arrangements for certain treaties. Such arrangements reduce the effect of individual or aggregate losses to all companies participating in such treaties, including the reinsurers. Our reinsurance group will continue to evaluate its retrocessional requirements. See note 4, "Reinsurance," of the notes accompanying our consolidated financial statements.

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        For catastrophe exposed reinsurance business, our reinsurance group seeks to limit the amount of exposure it assumes from any one reinsured and the amount of the aggregate exposure to catastrophe losses from a single event in any one geographic zone. For a discussion of our risk management policies, see "Management's Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies, Estimates and Recent Accounting Pronouncements—Ceded Reinsurance" and "Risk Factors—Risks Relating to Our Industry—The failure of any of the loss limitation methods we employ could have a material adverse effect on our financial condition or results of operations."

        Claims Management.     Claims management includes the receipt of initial loss reports, creation of claim files, determination of whether further investigation is required, establishment and adjustment of case reserves and payment of claims. Additionally, audits are conducted for both specific claims and overall claims procedures at the offices of selected ceding companies. Our reinsurance group makes use of outside consultants for claims work from time to time.

Employees

        As of February 15, 2009, ACGL and its subsidiaries employed approximately 1,200 full-time employees.

Reserves

        Reserve estimates are derived after extensive consultation with individual underwriters, actuarial analysis of the loss reserve development and comparison with industry benchmarks. Our reserves are established and reviewed by highly professional internal actuaries. Generally, reserves are established without regard to whether we may subsequently contest the claim. We do not currently discount our loss reserves except for excess workers' compensation and employers' liability loss reserves produced by Wexford, a new line of business for us in 2007.

        Loss reserves represent estimates of what the insurer or reinsurer ultimately expects to pay on claims at a given time, based on facts and circumstances then known, and it is probable that the ultimate liability may exceed or be less than such estimates. Even actuarially sound methods can lead to subsequent adjustments to reserves that are both significant and irregular due to the nature of the risks written. Loss reserves are inherently subject to uncertainty. In establishing the reserves for losses and loss adjustment expenses, we have made various assumptions relating to the pricing of our reinsurance contracts and insurance policies and have also considered available historical industry experience and current industry conditions. The timing and amounts of actual claim payments related to recorded reserves vary based on many factors including large individual losses, changes in the legal environment, as well as general market conditions. The ultimate amount of the claim payments could differ materially from our estimated amounts. Certain lines of business written by us, such as excess casualty, have loss experience characterized as low frequency and high severity. This may result in significant variability in loss payment patterns and, therefore, may impact the related asset/liability investment management process in order to be in a position, if necessary, to make these payments. See "Management's Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies, Estimates and Recent Accounting Pronouncements—Reserves for Losses and Loss Adjustment Expenses."

        The following table represents the development of loss reserves as determined under accounting principles generally accepted in the United States of America ("GAAP") for 1998 through 2008. This table does not present accident or policy year development data and, instead, presents an analysis of the claim development of gross and net balance sheet reserves existing at each calendar year-end in subsequent calendar years. The top line of the table shows the reserves, net of reinsurance recoverables, at the balance sheet date for each of the indicated years. This represents the estimated

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amounts of net losses and loss adjustment expenses arising in all prior years that are unpaid at the balance sheet date, including incurred but not reported ("IBNR") reserves. The table also shows the re-estimated amount of the previously recorded reserves based on experience as of the end of each succeeding year. The estimate changes as more information becomes known about the frequency and severity of claims for individual years. The "cumulative redundancy (deficiency)" represents the aggregate change in the estimates over all prior years. The table also shows the cumulative amounts paid as of successive years with respect to that reserve liability. In addition, the table reflects the claim development of the gross balance sheet reserves for ending reserves at December 31, 1998 through December 31, 2007. With respect to the information in the table, it should be noted that each amount includes the effects of all changes in amounts for prior periods.

        Results for 1998 to 2000 relate to our prior reinsurance operations, which were sold on May 5, 2000 to WTM Re. With respect to 2000, no reserves are reported in the table below because all reserves for business written through May 5, 2000 were assumed by WTM Re in the May 5, 2000 asset sale, and we did not write or assume any business during 2000 subsequent to the asset sale. Activity subsequent to 2000 relates to acquisitions made by us and our underwriting initiatives that commenced in October 2001.

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        The following table represents an analysis of losses and loss adjustment expenses and a reconciliation of the beginning and ending reserve for losses and loss adjustment expenses.

        Our reserving method to date has to a large extent been the expected loss method, which is commonly applied when limited loss experience exists. We select the initial expected loss and loss adjustment expense ratios based on information derived by our underwriters and actuaries during the initial pricing of the business, supplemented by industry data where appropriate. These ratios consider, among other things, rate changes and changes in terms and conditions that have been observed in the market. Any estimates and assumptions made as part of the reserving process could prove to be inaccurate due to several factors, including the fact that relatively limited historical information has been reported to us through December 31, 2008. As actual loss information is reported to us and we develop our own loss experience, we will give more emphasis to other actuarial techniques.

        During 2008, on a gross basis, we recorded a redundancy on reserves recorded in prior years of approximately $317.7 million while, on a net basis, we recorded a redundancy on reserves recorded in prior years of approximately $310.2 million. The net favorable development consisted of $231.2 million from the reinsurance segment and $79.0 million from the insurance segment. Of the net favorable development in the reinsurance segment, $126.1 million came from short-tail lines, and $105.1 million came from casualty and marine and aviation business. The development resulted from better than anticipated loss emergence. The net favorable development was partially offset by an increase in acquisition expenses of $11.1 million. In addition, in its reserving process in 2002 and 2003, the reinsurance segment recognized that there is a possibility that the assumptions made could prove to be inaccurate due to several factors primarily related to the start up nature of its operations. Due to the availability of additional data, and based on reserve analyses, it was determined that it was no longer necessary to continue to include such factors in 2004 or subsequent periods. Based on the level of claims activity reported to date, the reinsurance segment reduced the amount of reserves it had recorded in 2002 and 2003 by $2.7 million in 2008. Except as discussed above, the estimated favorable development in the reinsurance segment's prior year reserves did not reflect any significant changes in

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the key assumptions it made to estimate these reserves at December 31, 2007. As a result of applying a small amount of weight to its own experience, the insurance segment reduced loss selections for some lines, in particular those written on a claims-made basis and for which it now believes it has a reasonable level of credible data. The insurance segment's net favorable development of $79.0 million was primarily due to reductions in reserves in medium-tailed and long-tailed lines of business resulting from such changes. The net favorable development was partially offset by an increase in acquisition expenses of $15.9 million, primarily due to sliding scale arrangements on certain policies.

        During 2007, on a gross basis, we recorded a redundancy on reserves recorded in prior years of approximately $253.7 million while, on a net basis, we recorded a redundancy on reserves recorded in prior years of approximately $185.4 million. The net favorable development consisted of $172.7 million from the reinsurance segment and $12.7 million from the insurance segment. Of the net favorable development in the reinsurance segment, $110.6 million came from short-tail lines, and $62.1 million came from casualty and marine and aviation business. The development resulted from better than anticipated loss emergence. The net favorable development was partially offset by an increase in acquisition expenses of $18.5 million. In addition, in its reserving process in 2002 and 2003, the reinsurance segment recognized that there is a possibility that the assumptions made could prove to be inaccurate due to several factors primarily related to the start up nature of its operations. Due to the availability of additional data, and based on reserve analyses, it was determined that it was no longer necessary to continue to include such factors in 2004 or subsequent periods. Based on the level of claims activity reported to date, the reinsurance segment reduced the amount of reserves it had recorded in 2002 and 2003 by $10.6 million in 2007. Except as discussed above, the estimated favorable development in the reinsurance segment's prior year reserves did not reflect any significant changes in the key assumptions it made to estimate these reserves at December 31, 2006. As a result of applying a small amount of weight to its own experience, the insurance segment reduced loss selections for some lines, in particular those written on a claims-made basis and for which it now believes it has a reasonable level of credible data. The insurance segment's net favorable development of $12.7 million was primarily due to reductions in reserves in medium-tailed and long-tailed lines of business resulting from such changes, partially offset by adverse development of $33.3 million from short-tail lines which primarily resulted from higher than expected claims development. The net favorable development was partially offset by an increase in acquisition expenses of $9.5 million, primarily due to sliding scale arrangements on certain policies.

        During 2006, on a gross basis, we recorded a deficiency on reserves recorded in prior years of approximately $28.3 million while, on a net basis, we recorded a redundancy on reserves recorded in prior years of approximately $76.8 million. The gross deficiency primarily resulted from adverse development on the 2005 catastrophic events while, on a net basis, a significant portion of the adverse development was covered by reinsurance. The net favorable development consisted of $68.5 million from the reinsurance segment and $8.3 million from the insurance segment. Of the net favorable development in the reinsurance segment, $37.1 million came from short-tail lines, and $31.4 million came from longer-tail lines. The development resulted from better than anticipated loss emergence and was net of $38.1 million of adverse development on the 2005 catastrophic events, primarily in short-tail lines. The net favorable development was partially offset by an increase in acquisition expenses of $7.8 million. As noted above, in its reserving process in 2002 and 2003, the reinsurance segment recognized that there is a possibility that the assumptions made could prove to be inaccurate due to several factors primarily related to the start up nature of its operations. Due to the availability of additional data, and based on reserve analyses, it was determined that it was no longer necessary to continue to include such factors. Following reserve reviews, and based on the level of claims activity reported to date, the reinsurance segment reduced the amount of reserves it had recorded in 2002 and 2003 by $7.7 million in 2006. Except as discussed above, the estimated favorable development in the reinsurance segment's prior year reserves did not reflect any significant changes in the key assumptions it made to estimate these reserves at December 31, 2005. The insurance segment's net favorable development of $8.3 million was primarily due to reductions in reserves in certain medium-tailed and

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long-tailed lines of business, in particular for those lines of business written on a claims-made basis and for which it now believes it has a reasonable level of credible data, partially offset by adverse development of $44.0 million from short-tail lines which included $30.8 million of adverse development on the 2005 catastrophic events.

        We are subject to credit risk with respect to our reinsurance and retrocessions because the ceding of risk to reinsurers and retrocessionaires does not relieve us of our liability to the clients or companies we insure or reinsure. Our failure to establish adequate reinsurance or retrocessional arrangements or the failure of our existing reinsurance or retrocessional arrangements to protect us from overly concentrated risk exposure could adversely affect our financial condition and results of operations. Although we monitor the financial condition of our reinsurers and retrocessionaires and attempt to place coverages only with substantial, financially sound carriers, we may not be successful in doing so. See "Management's Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies, Estimates and Recent Accounting Pronouncements—Collection of Insurance-Related Balances and Provision for Doubtful Accounts."

Investments

        At December 31, 2008, consolidated cash and invested assets totaled approximately $10.0 billion, consisting of $832.9 million of cash and short-term investments, $8.75 billion of fixed maturities and fixed maturities pledged under securities lending agreements, $301.0 million of investment funds accounted for using the equity method and $109.6 million of other investments. See "Management's Discussion and Analysis of Financial Condition and Results of Operations—Financial Condition, Liquidity and Capital Resources—Financial Condition—Investable Assets" and note 7, "Investment Information," of the notes accompanying our financial statements.

        The following table summarizes the market value of our cash and invested assets at December 31, 2008 and 2007:

(1)

In our securities lending transactions, we receive collateral in excess of the market value of the fixed maturities and short-term investments pledged under securities lending agreements. For purposes of this table, we have excluded $730.2 million and $1.5 billion, respectively, of collateral received which is reflected as "investment of funds received under securities lending agreements, at market value" and included $728.1 million and $1.46 billion, respectively, of "fixed maturities and

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short-term investments pledged under securities lending agreements, at market value" at December 31, 2008 and 2007.

(2)

Includes certain securities transactions entered into but not settled at the balance sheet date. Net of such amounts, total cash and investments were approximately $9.97 billion at December 31, 2008 and $10.12 billion at December 31, 2007.

        Our current investment guidelines and approach stress preservation of capital, market liquidity and diversification of risk. Our investments are subject to market-wide risks and fluctuations, as well as to risks inherent in particular securities. At December 31, 2008, approximately 97% of our fixed maturities and fixed maturities pledged under securities lending agreements were rated investment grade by the major rating agencies, primarily Standard & Poor's Rating Services ("Standard & Poor's"), compared to 98% at December 31, 2007. At December 31, 2008 and 2007, our fixed maturities, fixed maturities pledged under securities lending agreements and short-term investments had an average credit quality rating of "AA+" and an average effective duration of approximately 3.62 years and 3.29 years, respectively.

        We participate in a securities lending program under which certain of our fixed income portfolio securities are loaned to third parties, primarily major brokerage firms, for short periods of time through a lending agent. Such securities have been reclassified as "Fixed maturities and short-term investments pledged under securities lending agreements, at market value." We maintain legal control over the securities we lend, retain the earnings and cash flows associated with the loaned securities and receive a fee from the borrower for the temporary use of the securities. Collateral received, primarily in the form of cash, is required at a rate of 102% of the market value of the loaned securities (or 105% of the market value of the loaned securities when the collateral and loaned securities are denominated in non-U.S. currencies) including accrued investment income and is monitored and maintained by the lending agent. Such collateral is reinvested and is reflected as "investment of funds received under securities lending agreements, at market value." At December 31, 2008, the market value and amortized cost of fixed maturities and short-term investments pledged under securities lending agreements were $728.1 million and $717.2 million, respectively, while collateral received totaled $753.5 million at market value and amortized cost. The market value of the reinvested collateral totaled $730.2 million at December 31, 2008. At December 31, 2007, the market value and amortized cost of fixed maturities and short-term investments pledged under securities lending agreements were $1.46 billion and $1.44 billion, respectively, while collateral received totaled $1.5 billion at market value and amortized cost.

        The credit quality distribution of our fixed maturities and fixed maturities pledged under securities lending agreements at December 31, 2008 and 2007 are shown below:

(1)

Ratings as assigned by the major rating agencies.

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        For 2008 and 2007, set forth below is the pre-tax total return (before investment expenses) of our investment portfolio (including fixed maturities, short-term investments and fixed maturities and short-term investments pledged under securities lending agreements) compared to the benchmark return against which we measured our portfolio during the year. Our investment expenses were approximately 0.14% of average invested assets in 2008, compared to 0.15% in 2007.

(1)

The benchmark return is a weighted average of the benchmarks assigned to each of our investment managers. The benchmarks used vary based on the nature of the portfolios under management. In all but a few instances, the benchmarks used are Lehman indices.

Ratings

        Our ability to underwrite business is dependent upon the quality of its claims paying ability and financial strength ratings as evaluated by independent agencies. Such ratings from third party internationally recognized statistical rating organizations or agencies are instrumental in establishing the competitive positions of companies in our industry. We believe that the primary users of such ratings include commercial and investment banks, policyholders, brokers, ceding companies and investors. Insurance ratings are also used by insurance and reinsurance intermediaries as an important means of assessing the financial strength and quality of insurers and reinsurers, and have become an increasingly important factor in establishing the competitive position of insurance and reinsurance companies. These ratings are often an important factor in the decision by an insured or intermediary of whether to place business with a particular insurance or reinsurance provider. Periodically, rating agencies evaluate us to confirm that we continue to meet their criteria for the ratings assigned to us by them. A.M. Best Company ("A.M. Best") maintains a letter scale rating system ranging from "A++" (Superior) to "F" (In Liquidation). Moody's Investors Service ("Moody's") maintains a letter scale rating from "Aaa" (Exceptional) to "NP" (Not Prime). Standard & Poor's maintains a letter scale rating system ranging from "AAA" (Extremely Strong) to "R" (Under Regulatory Supervision). Our reinsurance subsidiaries, Arch Re U.S., Arch Re Bermuda and Arch Re Europe (Standard & Poor's rating only), and our principal insurance subsidiaries, Arch Insurance, Arch E&S, Arch Specialty, Arch Indemnity (A.M. Best and Standard & Poor's rating only), and Arch Insurance Europe, each currently has a financial strength rating of "A" (Excellent, the third highest out of fifteen rating levels) with a stable outlook from A.M. Best, "A2" (Good, the sixth highest out of 21 rating levels) with a stable outlook from Moody's and "A" (Strong, the sixth highest out of 21 rating levels) with a stable outlook from Standard & Poor's. Fitch Ratings ("Fitch") has assigned a financial strength rating of "A+" (Strong, the fifth highest out of 24 rating levels) with a stable outlook to Arch Re Bermuda.

        ACGL has received counterparty (issuer) credit ratings of "BBB+" (eighth highest out of 22 rating levels) with a positive outlook from Standard & Poor's, "Baa1" (eighth highest out of 21 rating levels) with a stable outlook from Moody's and "A" long term issuer rating (sixth highest out of 23 rating levels) with a stable outlook from Fitch. A counterparty credit rating provides an opinion on an issuer's overall capacity and willingness to meet its financial commitments as they become due, but is not specific to a particular financial obligation. ACGL's senior debt was assigned a rating of "BBB+" from Standard & Poor's, "Baa1" from Moody's and "A-" from Fitch. ACGL's series A non-cumulative preferred shares and series B non-cumulative preferred shares were both assigned a "BBB-" rating by Standard & Poor's, a "Baa3" by Moody's and a "BBB+" rating by Fitch.

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        The financial strength ratings assigned by rating agencies to insurance and reinsurance companies represent independent opinions of financial strength and ability to meet policyholder obligations and are not directed toward the protection of investors, nor are they recommendations to buy, hold or sell any securities. We can offer no assurances that our ratings will remain at their current levels, or that our security will be accepted by brokers and our insureds and reinsureds. A ratings downgrade or the potential for such a downgrade, or failure to obtain a necessary rating, could adversely affect both our relationships with agents, brokers, wholesalers and other distributors of our existing products and services and new sales of our products and services. In addition, under certain of the reinsurance agreements assumed by our reinsurance operations, upon the occurrence of a ratings downgrade or other specified triggering event with respect to our reinsurance operations, such as a reduction in surplus by specified amounts during specified periods, our ceding company clients may be provided with certain rights, including, among other things, the right to terminate the subject reinsurance agreement and/or to require that our reinsurance operations post additional collateral. In the event of a ratings downgrade or other triggering event, the exercise of such contract rights by our clients could have a material adverse effect on our financial condition and results of operations, as well as our ongoing business and operations. See "Management's Discussion and Analysis of Financial Condition and Results of Operations—Financial Condition, Liquidity and Capital Resources—Liquidity and Capital Resources."

Competition

        The worldwide reinsurance and insurance businesses are highly competitive. We compete, and will continue to compete, with major U.S. and non-U.S. insurers and reinsurers, some of which have greater financial, marketing and management resources than we have and have had longer-term relationships with insureds and brokers than us. We compete with other insurers and reinsurers primarily on the basis of overall financial strength, ratings assigned by independent rating agencies, geographic scope of business, strength of client relationships, premiums charged, contract terms and conditions, products and services offered, speed of claims payment, reputation, employee experience, and qualifications and local presence. We also compete with new companies that continue to be formed to enter the insurance and reinsurance markets.

        In our insurance business, we compete with insurers that provide specialty property and casualty lines of insurance, including: ACE Limited, Allied World Assurance Company, Ltd., American International Group, Inc., AXIS Capital Holdings Limited, Berkshire Hathaway, Inc., Chubb Corporation, Endurance Specialty Holdings Ltd., The Hartford Financial Services Group, Inc., HCC Insurance Holdings, Inc., Lloyd's of London, The Travelers Companies, W.R. Berkley Corp., XL Capital Ltd. and Zurich Insurance Group. In our reinsurance business, we compete with reinsurers that provide property and casualty lines of reinsurance, including ACE Limited, AXIS Capital Holdings Limited, Berkshire Hathaway, Inc., Endurance Specialty Holdings Ltd., Everest Re Group Ltd., Hannover Rückversicherung AG, Lloyd's of London, Montpelier Re Holdings Ltd., Munich Re Group, PartnerRe Ltd., Platinum Underwriters Holdings, Ltd., RenaissanceRe Holdings Ltd., Swiss Reinsurance Company, Transatlantic Holdings, Inc. and XL Capital Ltd. We do not believe that we have a significant market share in any of our markets.

Regulation

U.S. Insurance Regulation

        General.     In common with other insurers, our U.S.-based subsidiaries are subject to extensive governmental regulation and supervision in the various states and jurisdictions in which they are domiciled and licensed and/or approved to conduct business. The laws and regulations of the state of domicile have the most significant impact on operations. This regulation and supervision is designed to protect policyholders rather than investors. Generally, regulatory authorities have broad regulatory

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powers over such matters as licenses, standards of solvency, premium rates, policy forms, marketing practices, claims practices, investments, security deposits, methods of accounting, form and content of financial statements, reserves and provisions for unearned premiums, unpaid losses and loss adjustment expenses, reinsurance, minimum capital and surplus requirements, dividends and other distributions to shareholders, periodic examinations and annual and other report filings. In addition, transactions among affiliates, including reinsurance agreements or arrangements, as well as certain third party transactions, require prior regulatory approval from, or prior notice to, the applicable regulator under certain circumstances. Certain insurance regulatory requirements are highlighted below. In addition, regulatory authorities conduct periodic financial, claims and market conduct examinations. Arch Insurance Europe is also subject to certain governmental regulation and supervision in the various states where it has been approved as an excess and surplus lines insurer.

        The New York Attorney General, various state insurance regulatory authorities and others continue to prosecute actions arising out of contingent commission payments to brokers (and the disclosures relating to such payments), "bid-rigging," "steering," and other practices in the insurance industry. Although certain brokers have announced new fee structures in response to the industry investigations and, as part of these new initiatives, have requested that our insurance subsidiaries enter into standardized payment arrangements, we have determined to negotiate payment arrangements with our brokers on a case by case basis. However, this has not affected certain agreements between our insurance subsidiaries and managing general agents providing for the payment to such agents of additional commissions based upon the profitability of the business produced by those agents. We cannot predict the effect that these prosecutions, any related investigations and/or resulting changes in insurance practices (including future legislation and/or regulations that may become applicable to our business) will have on the insurance industry, the regulatory framework or our business. See "Risk Factors—Risks Relating to Our Industry—Our reliance on brokers subjects us to their credit risk."

        Credit for Reinsurance.     Arch Re U.S. is subject to insurance regulation and supervision that is similar to the regulation of licensed primary insurers. However, except for certain mandated provisions that must be included in order for a ceding company to obtain credit for reinsurance ceded, the terms and conditions of reinsurance agreements generally are not subject to regulation by any governmental authority. This contrasts with admitted primary insurance policies and agreements, the rates and terms of which generally are regulated by state insurance regulators. As a practical matter, however, the rates charged by primary insurers do have an effect on the rates that can be charged by reinsurers.

        A primary insurer ordinarily will enter into a reinsurance agreement only if it can obtain credit for the reinsurance ceded on its U.S. statutory-basis financial statements. In general, credit for reinsurance is allowed in the following circumstances:

•

if the reinsurer is licensed in the state in which the primary insurer is domiciled or, in some instances, in certain states in which the primary insurer is licensed;



•

if the reinsurer is an "accredited" or otherwise approved reinsurer in the state in which the primary insurer is domiciled or, in some instances, in certain states in which the primary insurer is licensed;



•

in some instances, if the reinsurer (a) is domiciled in a state that is deemed to have substantially similar credit for reinsurance standards as the state in which the primary insurer is domiciled and (b) meets certain financial requirements; or



•

if none of the above apply, to the extent that the reinsurance obligations of the reinsurer are collateralized appropriately, typically through the posting of a letter of credit for the benefit of the primary insurer or the deposit of assets into a trust fund established for the benefit of the primary insurer.

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        As a result of the requirements relating to the provision of credit for reinsurance, Arch Re U.S. and Arch Re Bermuda are indirectly subject to certain regulatory requirements imposed by jurisdictions in which ceding companies are licensed.

        As of February 15, 2009: (1) Arch Re U.S. is licensed or is an accredited or otherwise approved reinsurer in 50 states and the District of Columbia; (2) Arch Insurance is licensed as an insurer in 50 states, the District of Columbia, Puerto Rico, the U.S. Virgin Islands and Guam with a branch office in Canada; (3) Arch Specialty is licensed in one state and approved as an excess and surplus lines insurer in 49 states, the District of Columbia, Puerto Rico and the U.S. Virgin Islands; (4) Arch E&S is licensed in one state and approved as an excess and surplus lines insurer in 47 states and the District of Columbia; (5) Arch Indemnity is licensed as an insurer in 49 states and the District of Columbia; and (6) Arch Insurance Europe is approved as an excess and surplus lines insurer in 16 states and the District of Columbia. Neither Arch Re Bermuda nor Arch Re Europe expects to become licensed, accredited or so approved in any U.S. jurisdiction.

        Holding Company Acts.     All states have enacted legislation that regulates insurance holding company systems. These regulations generally provide 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 affecting insurers must be fair and reasonable. 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 any entity in its holding company system. In addition, certain of such transactions cannot be consummated without the applicable insurance department's prior approval.

        Regulation of Dividends and Other Payments from Insurance Subsidiaries.     The ability of an insurer to pay dividends or make other distributions is subject to insurance regulatory limitations of the insurance company's state of domicile. Generally, such laws limit the payment of dividends or other distributions above a specified level. Dividends or other distributions in excess of such thresholds are "extraordinary" and are subject to prior regulatory approval. Such dividends or distributions may be subject to applicable withholding or other taxes. See "Management's Discussion and Analysis of Financial Condition and Results of Operations—Financial Condition, Liquidity and Capital Resources—Liquidity and Capital Resources" and note 15, "Statutory Information," of the notes accompanying our financial statements.

        Insurance Regulatory Information System Ratios.     The National Association of Insurance Commissioners ("NAIC") Insurance Regulatory Information System ("IRIS") was developed by a committee of state insurance regulators and is intended primarily to assist state insurance departments in executing their statutory mandates to oversee the financial condition of insurance companies operating in their respective states. IRIS identifies 13 industry ratios (referred to as "IRIS ratios") and specifies "usual values" for each ratio. Departure from the usual values of the IRIS ratios can lead to inquiries from individual state insurance commissioners as to certain aspects of an insurer's business. For 2008, certain of our U.S.-based subsidiaries generated IRIS ratios that were outside of the usual values. To date, none of these subsidiaries has received any notice of regulatory review but there is no assurance that we may not be notified in the future.

        Accreditation.     The NAIC has instituted its Financial Regulatory Accreditation Standards Program ("FRASP") in response to federal initiatives to regulate the business of insurance. FRASP provides a set of standards designed to establish effective state regulation of the financial condition of insurance companies. Under FRASP, a state must adopt certain laws and regulations, institute required regulatory practices and procedures, and have adequate personnel to enforce such items in order to become an "accredited" state. If a state is not accredited, other states may not accept certain financial examination

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reports of insurers prepared solely by the regulatory agency in such unaccredited state. The respective states in which Arch Re U.S., Arch Insurance, Arch E&S, Arch Specialty and Arch Indemnity are domiciled are accredited states.

        Risk-Based Capital Requirements.     In order to enhance the regulation of insurer solvency, the NAIC adopted in December 1993 a formula and model law to implement risk-based capital requirements for property and casualty insurance companies. These risk-based capital requirements are designed to assess capital adequacy and to raise the level of protection that statutory surplus provides for policyholder obligations. The risk-based capital model for property and casualty insurance companies measures three major areas of risk facing property and casualty insurers:

•

underwriting, which encompasses the risk of adverse loss developments and inadequate pricing;



•

declines in asset values arising from credit risk; and



•

declines in asset values arising from investment risks.

        An insurer will be subject to varying degrees of regulatory action depending on how its statutory surplus compares to its risk-based capital calculation. Equity investments in common stock typically are valued at 85% of their market value under the risk-based capital guidelines. For equity investments in an insurance company affiliate, the risk-based capital requirements for the equity securities of such affiliate would generally be our U.S.-based subsidiaries' proportionate share of the affiliate's risk-based capital requirement.

        Under the approved formula, an insurer's total adjusted capital is compared to its authorized control level risk-based capital. If this ratio is above a minimum threshold, no company or regulatory action is necessary. Below this threshold are four distinct action levels at which a regulator can intervene with increasing degrees of authority over an insurer as the ratio of surplus to risk-based capital requirement decreases. The four action levels include:

•

insurer is required to submit a plan for corrective action;



•

insurer is subject to examination, analysis and specific corrective action;



•

regulators may place insurer under regulatory control; and



•

regulators are required to place insurer under regulatory control.

        Each of our U.S. subsidiaries' surplus (as calculated for statutory purposes) is above the risk-based capital thresholds that would require either company or regulatory action.

        Guaranty Funds and Assigned Risk Plans.     Most states require all admitted insurance companies to participate in their respective guaranty funds which cover certain claims against insolvent insurers. Solvent insurers licensed in these states are required to cover the losses paid on behalf of insolvent insurers by the guaranty funds and are generally subject to annual assessments in the states by the guaranty funds to cover these losses. Participation in state-assigned risk plans may take the form of reinsuring a portion of a pool of policies or the direct issuance of policies to insureds. The calculation of an insurer's participation in these plans is usually based on the amount of premium for that type of coverage that was written by the insurer on a voluntary basis in a prior year. Assigned risk pools tend to produce losses which result in assessments to insurers writing the same lines on a voluntary basis.

        Federal Regulation.     Although state regulation is the dominant form of regulation for insurance and reinsurance business, the federal government has shown increasing concern over the adequacy of state regulation. It is not possible to predict the future impact of any potential federal regulations or other possible laws or regulations on our U.S.-based subsidiaries' capital and operations, and such laws or regulations could materially adversely affect their business.

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        Terrorism Risk Insurance Program Reauthorization Act of 2007.     On November 26, 2002, President Bush signed into law the Terrorism Risk Insurance Act of 2002, which was amended and extended by the Terrorism Risk Insurance Extension Act of 2005 and amended and extended again by the Terrorism Risk Insurance Program Reauthorization Act of 2007 ("TRIPRA") through December 31, 2014. TRIPRA provides a federal backstop for insurance-related losses resulting from any act of terrorism on U.S. soil or against certain U.S. air carriers, vessels or foreign missions. Under TRIPRA, all U.S.-based property and casualty insurers are required to make terrorism insurance coverage available in specified commercial property and casualty insurance lines. Under TRIPRA, the federal government will pay 85% of covered losses after an insurer's losses exceed a deductible determined by a statutorily prescribed formula, up to a combined annual aggregate limit for the federal government and all insurers of $100 billion. If an act (or acts) of terrorism result in covered losses exceeding the $100 billion annual limit, insurers with losses exceeding their deductibles will not be responsible for additional losses. The deductible for each year is based on the insurer's direct commercial earned premiums for property and casualty insurance, excluding certain lines of business such as commercial auto, surety, professional liability and earthquake lines of business, for the prior calendar year multiplied by 20%. The specified percentages for prior periods were 10% for 2004, 15% for 2005, 17.5% for 2006, 20% for 2007 and 20% for 2008, which extends through 2014.

        Our U.S.-based property and casualty insurers, Arch Insurance, Arch Specialty, Arch E&S and Arch Indemnity, are subject to TRIPRA. TRIPRA specifically excludes reinsurance business and, accordingly, does not apply to our reinsurance operations. Our U.S. insurance group's deductible for 2008 was approximately $261.7 million (i.e., 20.0% of earned premiums). Based on 2008 direct commercial earned premiums, our U.S. insurance group's deductible for 2009 is approximately $244.1 million (i.e., 20.0% of such earned premiums).

        The Gramm-Leach-Bliley Act.     The Gramm-Leach-Bliley Act of 1999 ("GLBA"), which implements fundamental changes in the regulation of the financial services industry in the United States, was enacted on November 12, 1999. The GLBA permits the transformation of the already converging banking, insurance and securities industries by permitting mergers that combine commercial banks, insurers and securities firms under one holding company, a "financial holding company." Bank holding companies and other entities that qualify and elect to be treated as financial holding companies may engage in activities, and acquire companies engaged in activities, that are "financial" in nature or "incidental" or "complementary" to such financial activities. Such financial activities include acting as principal, agent or broker in the underwriting and sale of life, property, casualty and other forms of insurance and annuities.

        Until the passage of the GLBA, the Glass-Steagall Act of 1933 had limited the ability of banks to engage in securities-related businesses, and the Bank Holding Company Act of 1956 had restricted banks from being affiliated with insurers. With the passage of the GLBA, among other things, bank holding companies may acquire insurers, and insurance holding companies may acquire banks. The ability of banks to affiliate with insurers may affect our U.S. subsidiaries' product lines by substantially increasing the number, size and financial strength of potential competitors.

        Legislative and Regulatory Proposals.     From time to time various regulatory and legislative changes have been proposed in the insurance and reinsurance industry. Among the proposals that have in the past been or are at present being considered are the possible introduction of federal regulation in addition to, or in lieu of, the current system of state regulation of insurers. In addition, there are a variety of proposals being considered by various state legislatures. In December 2008, the NAIC adopted its Reinsurance Regulatory Modernization Framework Proposal (the "Reinsurance Proposal"), which aims to eliminate the universal 100 percent collateral requirement presently imposed on foreign reinsurers, such as Arch Re Bermuda, and establishes instead a sliding scale percentage rating system for assessing collateral obligations. To this end, the Reinsurance Proposal creates two new classes of reinsurers in the United States: "national" reinsurers and "port of entry" ("POE") reinsurers. A national reinsurer is licensed and domiciled in a U.S. home state and approved by such state to