CB 2010 10-K

Chubb Corp (CB) SEC Annual Report (10-K) for 2011

CB Q3 2012 10-Q
CB 2010 10-K CB Q3 2012 10-Q
Table of Contents

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D. C. 20549

FORM 10-K

x ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, 2011
OR
o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO
Commission File No. 1-8661

The Chubb Corporation

(Exact name of registrant as specified in its charter)

New Jersey 13-2595722
(State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.)
15 Mountain View Road
Warren, New Jersey

07059
(Address of principal executive offices) (Zip Code)
(908) 903-2000
(Registrant's telephone number, including area code)
Securities registered pursuant to Section 12(b) of the Act:
(Title of each class) (Name of each exchange on which registered)
Common Stock, par value $1 per share New York Stock Exchange
Series B Participating Cumulative New York Stock Exchange
Preferred Stock Purchase Rights
Securities registered pursuant to Section 12(g) of the Act:
None
(Title of class)

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes [ ü ] No [  ]

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act. Yes [  ] No [ ü ]

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes [ ü ] No [  ]

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes [ ü ] No [  ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of the registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. [ ü ]

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act. (Check one):

Large accelerated filer [ ü ] Accelerated filer [  ]
Non-accelerated filer [  ]
(Do not check if a smaller reporting company)
Smaller reporting company [  ]

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes [  ] No [ ü ]

The aggregate market value of common stock held by non-affiliates of the registrant was $17,852,043,816 as of June 30, 2011, computed on the basis of the closing sale price of the common stock on that date.

271,126,567

Number of shares of common stock outstanding as of February 10, 2012

Documents Incorporated by Reference

Portions of the definitive Proxy Statement for the 2012 Annual Meeting of Shareholders are incorporated by reference in Part III of this Form 10-K.

CONTENTS

ITEM DESCRIPTION PAGE

PART I

1

Business

3
1A

Risk Factors

12
1B

Unresolved Staff Comments

21
2

Properties

21
3

Legal Proceedings

21

PART II

5
Market for the Registrant's Common Equity,
Related Stockholder Matters and Issuer Purchases of Equity Securities
23
6

Selected Financial Data

25
7

Management's Discussion and Analysis of Financial Condition and Results of Operations

26
7A

Quantitative and Qualitative Disclosures About Market Risk

66
8

Consolidated Financial Statements and Supplementary Data

70
9
Changes in and Disagreements with Accountants
on Accounting and Financial Disclosure
70
9A

Controls and Procedures

70
9B

Other Information

71

PART III

10

Directors, Executive Officers and Corporate Governance

73
11

Executive Compensation

73
12
Security Ownership of Certain Beneficial Owners and Management
and Related Stockholder Matters
73
13

Certain Relationships and Related Transactions, and Director Independence

73
14

Principal Accountant Fees and Services

73

PART IV

15

Exhibits, Financial Statements and Schedules

73

Signatures

74

Index to Financial Statements and Financial Statement Schedules

F-1

Exhibits Index

E-1
EX-12.1
EX-21.1
EX-23.1
EX-31.1
EX-31.2
EX-32.1
EX-32.2
EX-101 INSTANCE DOCUMENT
EX-101 SCHEMA DOCUMENT
EX-101 CALCULATION LINKBASE DOCUMENT
EX-101 LABELS LINKBASE DOCUMENT
EX-101 PRESENTATION LINKBASE DOCUMENT
EX-101 DEFINITION LINKBASE DOCUMENT

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PART I.

Item 1.   Business

General

The Chubb Corporation (Chubb) was incorporated as a business corporation under the laws of the State of New Jersey in June 1967. Chubb and its subsidiaries are referred to collectively as the Corporation. Chubb is a holding company for a family of property and casualty insurance companies known informally as the Chubb Group of Insurance Companies (the P&C Group). Since 1882, the P&C Group has provided property and casualty insurance to businesses and individuals around the world. According to A.M. Best, the P&C Group is the 12th largest U.S. property and casualty insurance group based on 2010 net written premiums.

At December 31, 2011, the Corporation had total assets of $50.9 billion and shareholders' equity of $15.6 billion. Revenues, income before income tax and assets for each operating segment for the three years ended December 31, 2011 are included in Note (14) of the Notes to Consolidated Financial Statements. The Corporation employed approximately 10,100 persons worldwide on December 31, 2011.

The Corporation's principal executive offices are located at 15 Mountain View Road, Warren, New Jersey 07059, and our telephone number is (908) 903-2000.

The Corporation's Internet address is www.chubb.com. The Corporation's 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)of the Securities Exchange Act of 1934 are available free of charge on this website as soon as reasonably practicable after they have been electronically filed with or furnished to the Securities and Exchange Commission. Chubb's Corporate Governance Guidelines, charters of certain key committees of its Board of Directors, Restated Certificate of Incorporation, By-Laws, Code of Business Conduct and Code of Ethics for CEO and Senior Financial Officers are also available on the Corporation's website or by writing to the Corporation's Corporate Secretary.

Property and Casualty Insurance

The P&C Group is divided into three strategic business units. Chubb Personal Insurance offers coverage of fine homes, automobiles and other personal possessions along with options for high limits of personal liability coverage. Chubb Personal Insurance also provides supplemental accident and health insurance in niche markets. Chubb Commercial Insurance offers a full range of commercial insurance products, including coverage for multiple peril, casualty, workers' compensation and property and marine. Chubb Commercial Insurance is known for writing niche business, where our expertise can add value for our agents, brokers and policyholders. Chubb Specialty Insurance offers a wide variety of specialized professional liability products for privately and publicly owned companies, financial institutions, professional firms and healthcare organizations. Chubb Specialty Insurance also includes our surety business.

The P&C Group provides insurance coverages principally in the United States, Canada, Europe, Australia, and parts of Latin America and Asia. Revenues of the P&C Group by geographic area for the three years ended December 31, 2011 are included in Note (14) of the Notes to Consolidated Financial Statements.

The principal members of the P&C Group are Federal Insurance Company (Federal), Pacific Indemnity Company (Pacific Indemnity), Executive Risk Indemnity Inc. (Executive Risk Indemnity), Great Northern Insurance Company (Great Northern), Vigilant Insurance Company (Vigilant), Chubb National Insurance Company (Chubb National), Chubb Indemnity Insurance Company (Chubb Indemnity), Chubb Custom Insurance Company, Executive Risk Specialty Insurance Company (Executive Risk Specialty), Northwestern Pacific Indemnity Company, Texas Pacific Indemnity Company (Texas Pacific Indemnity) and Chubb Insurance Company of New Jersey (Chubb New Jersey) in the United States, as well as Chubb Atlantic Indemnity Ltd. (a Bermuda company), Chubb Insurance Company of Canada, Chubb Insurance Company of Europe SE, Chubb Capital Ltd. (a United Kingdom company),

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Chubb Insurance Company of Australia Ltd., Chubb Argentina de Seguros, S.A., Chubb Insurance (China) Company Limited and Chubb do Brasil Companhia de Seguros.

Chubb & Son, a division of Federal, is the manager of Pacific Indemnity, Executive Risk Indemnity, Great Northern, Vigilant, Chubb National, Chubb Indemnity, Executive Risk Specialty, Texas Pacific Indemnity and Chubb New Jersey. Chubb & Son also provides certain services to other members of the P&C Group. Acting subject to the supervision and control of the boards of directors of the members of the P&C Group, Chubb & Son provides day to day executive management and operating personnel and makes available the economy and flexibility inherent in the common operation of a group of insurance companies.

Premiums Written

A summary of the P&C Group's premiums written during the past three years is shown in the following table:

Direct
Reinsurance
Reinsurance
Net
Premiums
Premiums
Premiums
Premiums
Year Written Assumed(a) Ceded(a) Written
(in millions)

2011

$ 12,302 $ 548 $ 1,092 $ 11,758

2010

11,952 391 1,107 11,236

2009

11,813 370 1,106 11,077

(a) Intercompany items eliminated.

The net premiums written during the last three years for major classes of the P&C Group's business are included in the Property and Casualty Insurance - Underwriting Results section of Management's Discussion and Analysis of Financial Condition and Results of Operations (MD&A).

One or more members of the P&C Group are licensed and transact business in each of the 50 states of the United States, the District of Columbia, Puerto Rico, the Virgin Islands, Canada, Europe, Australia, and parts of Latin America and Asia. In 2011, approximately 75% of the P&C Group's direct premiums written were produced in the United States, where the P&C Group's businesses enjoy broad geographic distribution with a particularly strong market presence in the Northeast. The five states accounting for the largest amounts of direct premiums written were New York with 12%, California with 9%, Texas with 5%, Florida with 4% and New Jersey with 4%. Of the approximately 25% of the P&C Group's direct premiums written that were produced outside of the United States, approximately 5% were produced in the United Kingdom, 5% in Canada, 4% in Brazil and 3% in Australia.

Underwriting Results

A frequently used industry measurement of property and casualty insurance underwriting results is the combined loss and expense ratio. The P&C Group uses the combined loss and expense ratio calculated in accordance with statutory accounting principles applicable to property and casualty insurance companies. This ratio is the sum of the ratio of losses and loss expenses to premiums earned (loss ratio) plus the ratio of statutory underwriting expenses to premiums written (expense ratio) after reducing both premium amounts by dividends to policyholders. When the combined ratio is under 100%, underwriting results are generally considered profitable; when the combined ratio is over 100%, underwriting results are generally considered unprofitable. Investment income is not reflected in the combined ratio. The profitability of property and casualty insurance companies depends on the results of both underwriting and investments operations.

The combined loss and expense ratios during the last three years in total and for the major classes of the P&C Group's business are included in the Property and Casualty Insurance - Underwriting Operations section of MD&A.

Another frequently used measurement in the property and casualty insurance industry is the ratio of statutory net premiums written to policyholders' surplus. At December 31, 2011 and 2010, the ratio for the P&C Group was 0.84 and 0.77, respectively.

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Producing and Servicing of Business

The P&C Group does not utilize a significant in-house distribution model for its products. Instead, in the United States, the P&C Group offers products through independent insurance agencies and accepts business on a regular basis from insurance brokers. In most instances, these agencies and brokers also offer products of other companies that compete with the P&C Group. The P&C Group's branch and service offices assist these agencies and brokers in producing and servicing the P&C Group's business. In addition to the administrative offices in Warren and Whitehouse Station, New Jersey, the P&C Group has territory, branch and service offices throughout the United States.

The P&C Group primarily offers products through insurance brokers outside the United States. Local branch offices of the P&C Group assist the brokers in producing and servicing the business. In conducting its foreign business, the P&C Group mitigates the risks relating to currency fluctuations by generally maintaining investments in those foreign currencies in which the P&C Group has loss reserves and other liabilities. The net asset or liability exposure to the various foreign currencies is regularly reviewed.

Business for the P&C Group is also produced through participation in certain underwriting pools and syndicates. Such pools and syndicates provide underwriting capacity for risks which an individual insurer cannot prudently underwrite because of the magnitude of the risk assumed or which can be more effectively handled by one organization due to the need for specialized loss control and other services.

Reinsurance Ceded

In accordance with the normal practice of the insurance industry, the P&C Group cedes reinsurance to reinsurance companies. Reinsurance is ceded to provide greater diversification of risk and to limit the P&C Group's maximum net loss arising from large risks or from catastrophic events.

A large portion of the P&C Group's ceded reinsurance is effected under contracts known as treaties under which all risks meeting prescribed criteria are automatically covered. Most of the P&C Group's treaty reinsurance arrangements consist of excess of loss and catastrophe contracts that protect against a specified part or all of certain types of losses over stipulated amounts arising from any one occurrence or event. In certain circumstances, reinsurance is also effected by negotiation on individual risks. The amount of each risk retained by the P&C Group is subject to maximum limits that vary by line of business and type of coverage. Retention limits are regularly reviewed and are revised periodically as the P&C Group's capacity to underwrite risks changes. For a discussion of the P&C Group's reinsurance program and the cost and availability of reinsurance, see the Property and Casualty Insurance - Underwriting Results section of MD&A.

Ceded reinsurance contracts do not relieve the P&C Group of the primary obligation to its policyholders. Thus, a credit exposure exists with respect to reinsurance recoverable to the extent that any reinsurer is unable to meet its obligations or disputes the liabilities assumed under the reinsurance contracts. The collectibility of reinsurance is subject to the solvency of the reinsurers, coverage interpretations and other factors. The P&C Group is selective in regard to its reinsurers, placing reinsurance with only those reinsurers that the P&C Group believes have strong balance sheets and superior underwriting ability. The P&C Group monitors the financial strength of its reinsurers on an ongoing basis.

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Unpaid Losses and Loss Adjustment Expenses and Related Amounts Recoverable from Reinsurers

Insurance companies are required to establish a liability in their accounts for the ultimate costs (including loss adjustment expenses) of claims that have been reported but not settled and of claims that have been incurred but not reported. Insurance companies are also required to report as assets the portion of such liability that will be recovered from reinsurers.

The process of establishing the liability for unpaid losses and loss adjustment expenses is complex and imprecise as it must take into consideration many variables that are subject to the outcome of future events. As a result, informed subjective estimates and judgments as to our ultimate exposure to losses are an integral component of our loss reserving process.

The anticipated effect of inflation is implicitly considered when estimating liabilities for unpaid losses and loss adjustment expenses. Estimates of the ultimate value of all unpaid losses are based in part on the development of paid losses, which reflect actual inflation. Inflation is also reflected in the case estimates established on reported open claims which, when combined with paid losses, form another basis to derive estimates of reserves for all unpaid losses. There is no precise method for subsequently evaluating the adequacy of the consideration given to inflation, since claim settlements are affected by many factors.

The P&C Group continues to emphasize early and accurate reserving, inventory management of claims and suits, and control of the dollar value of settlements. The number of outstanding claims at year-end 2011 was approximately 11% higher than the number at year-end 2010 primarily due to an increase in outstanding catastrophe claims. The number of new arising claims during 2011 was approximately 8% higher than in the prior year.

Additional information related to the P&C Group's estimates related to unpaid losses and loss adjustment expenses and the uncertainties in the estimation process is presented in the Property and Casualty Insurance - Loss Reserves section of MD&A.

The table on page 7 presents the subsequent development of the estimated year-end liability for unpaid losses and loss adjustment expenses, net of reinsurance recoverable, for the ten years prior to 2011.

The top line of the table shows the estimated net liability for unpaid losses and loss adjustment expenses recorded at the balance sheet date for each of the indicated years. This liability represents the estimated amount of losses and loss adjustment expenses for claims arising in all years prior to the balance sheet date that were unpaid at the balance sheet date, including losses that had been incurred but not yet reported to the P&C Group.

The upper section of the table shows the reestimated amount of the previously recorded net liability based on experience as of the end of each succeeding year. The estimate is increased or decreased as more information becomes known about the frequency and severity of losses for each individual year. The increase or decrease is reflected in operating results of the period in which the estimate is changed. The "cumulative deficiency (redundancy)" as shown in the table represents the aggregate change in the reserve estimates from the original balance sheet dates through December 31, 2011. The amounts noted are cumulative in nature; that is, an increase in a loss estimate that is related to a prior period occurrence generates a deficiency in each intermediate year. For example, a deficiency recognized in 2011 relating to losses incurred prior to December 31, 2001 would be included in the cumulative deficiency amount for each year in the period 2001 through 2010. Yet, the deficiency would be reflected in operating results only in 2011. The effect of changes in estimates of the liabilities for losses occurring in prior years on income before income taxes in each of the past three years is shown in the reconciliation of the beginning and ending liability for unpaid losses and loss adjustment expenses in the Property and Casualty Insurance - Loss Reserves section of MD&A.

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ANALYSIS OF LOSS AND LOSS ADJUSTMENT EXPENSE DEVELOPMENT

December 31
Year Ended 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
(in millions)

Net Liability for Unpaid Losses and Loss Adjustment Expenses

$ 11,010 $ 12,642 $ 14,521 $ 16,809 $ 18,713 $ 19,699 $ 20,316 $ 20,155 $ 20,786 $ 20,901 $ 21,329

Net Liability Reestimated as of:

One year later

11,799 13,039 14,848 16,972 18,417 19,002 19,443 19,393 20,040 20,134

Two years later

12,143 13,634 15,315 17,048 17,861 18,215 18,619 18,685 19,229

Three years later

12,642 14,407 15,667 16,725 17,298 17,571 18,049 17,965

Four years later

13,246 14,842 15,584 16,526 16,884 17,184 17,510

Five years later

13,676 14,907 15,657 16,411 16,636 16,829

Six years later

13,812 15,064 15,798 16,310 16,459

Seven years later

13,994 15,255 15,802 16,231

Eight years later

14,218 15,305 15,801

Nine years later

14,301 15,323

Ten years later

14,344
Total Cumulative Net Deficiency
(Redundancy)
3,334 2,681 1,280 (578 ) (2,254 ) (2,870 ) (2,806 ) (2,190 ) (1,557 ) (767 )

Cumulative Net Deficiency Related to Asbestos and Toxic Waste Claims (Included in Above Total)

1,521 780 530 455 420 396 308 223 133 72
Cumulative Amount of
Net Liability Paid as of:

One year later

3,135 3,550 3,478 3,932 4,118 4,066 4,108 4,063 4,074 4,300

Two years later

5,499 5,911 6,161 6,616 6,896 6,789 6,565 6,711 6,831

Three years later

7,133 7,945 8,192 8,612 8,850 8,554 8,436 8,605

Four years later

8,564 9,396 9,689 10,048 10,089 9,884 9,734

Five years later

9,588 10,543 10,794 10,977 10,994 10,821

Six years later

10,366 11,353 11,530 11,606 11,697

Seven years later

10,950 11,915 12,037 12,149

Eight years later

11,390 12,292 12,497

Nine years later

11,681 12,652

Ten years later

11,991

Gross Liability, End of Year

$ 15,515 $ 16,713 $ 17,948 $ 20,292 $ 22,482 $ 22,293 $ 22,623 $ 22,367 $ 22,839 $ 22,718 $ 23,068

Reinsurance Recoverable, End of Year

4,505 4,071 3,427 3,483 3,769 2,594 2,307 2,212 2,053 1,817 1,739

Net Liability, End of Year

$ 11,010 $ 12,642 $ 14,521 $ 16,809 $ 18,713 $ 19,699 $ 20,316 $ 20,155 $ 20,786 $ 20,901 $ 21,329

Reestimated Gross Liability

$ 19,894 $ 20,209 $ 19,667 $ 19,680 $ 19,975 $ 19,296 $ 19,678 $ 20,083 $ 21,235 $ 21,890

Reestimated Reinsurance Recoverable

5,550 4,886 3,866 3,449 3,516 2,467 2,168 2,118 2,006 1,756

Reestimated Net Liability

$ 14,344 $ 15,323 $ 15,801 $ 16,231 $ 16,459 $ 16,829 $ 17,510 $ 17,965 $ 19,229 $ 20,134
Cumulative Gross Deficiency
(Redundancy)
$ 4,379 $ 3,496 $ 1,719 $ (612 ) $ (2,507 ) $ (2,997 ) $ (2,945 ) $ (2,284 ) $ (1,604 ) $ (828 )

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The subsequent development of the net liability for unpaid losses and loss adjustment expenses as of year-ends 2001 through 2003 was adversely affected by substantial unfavorable development related to asbestos and toxic waste claims. The cumulative net deficiencies experienced related to asbestos and toxic waste claims were the result of: (1) an increase in the actual number of claims filed; (2) an increase in the estimated number of potential claims; (3) an increase in the severity of actual and potential claims; (4) an increasingly adverse litigation environment; and (5) an increase in litigation costs associated with such claims. For the years 2001 through 2003, in addition to the unfavorable development related to asbestos and toxic waste claims, there was significant unfavorable development in the professional liability classes - principally directors and officers liability and errors and omissions liability, due in large part to adverse loss trends related to corporate failures and allegations of management misconduct and accounting irregularities - and, to a lesser extent, workers' compensation and commercial casualty classes. For the years 2004 through 2010, unfavorable development related to asbestos and toxic waste claims was more than offset by significant favorable development, primarily in the professional liability classes and more recently in the commercial casualty classes due to favorable loss trends in recent years and in the commercial property and homeowners classes due to lower than expected emergence of losses.

Conditions and trends that have affected development of the liability for unpaid losses and loss adjustment expenses in the past will not necessarily recur in the future. Accordingly, it is not appropriate to extrapolate future redundancies or deficiencies based on the data in this table.

The middle section of the table on page 7 shows the cumulative amount paid with respect to the reestimated net liability as of the end of each succeeding year. For example, in the 2001 column, as of December 31, 2011 the P&C Group had paid $11,991 million of the currently estimated $14,344 million of net losses and loss adjustment expenses that were unpaid at the end of 2001; thus, an estimated $2,353 million of net losses incurred on or before December 31, 2001 remain unpaid as of December 31, 2011, approximately 37% of which relates to asbestos and toxic waste claims.

The lower section of the table on page 7 shows the gross liability, reinsurance recoverable and net liability recorded at the balance sheet date for each of the indicated years and the reestimation of these amounts as of December 31, 2011.

The liability for unpaid losses and loss adjustment expenses, net of reinsurance recoverable, reported in the accompanying consolidated financial statements prepared in accordance with generally accepted accounting principles (GAAP) comprises the liabilities of U.S. and foreign members of the P&C Group as follows:

December 31
2011 2010
(in millions)

U.S. subsidiaries

$ 17,500 $ 17,193

Foreign subsidiaries

3,829 3,708
$ 21,329 $ 20,901

Members of the P&C Group are required to file annual statements with insurance regulatory authorities prepared on an accounting basis prescribed or permitted by such authorities (statutory basis). The difference between the liability for unpaid losses and loss expenses, net of reinsurance recoverable, reported in the statutory basis financial statements of the U.S. members of the P&C Group and such liability reported on a GAAP basis in the consolidated financial statements is not significant.

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Investments

Investment decisions are centrally managed by investment professionals based on guidelines established by management and approved by the respective boards of directors for each company in the P&C Group.

Additional information about the Corporation's investment portfolio as well as its approach to managing risks is presented in the Invested Assets section of MD&A, the Investment Portfolio section of Quantitative and Qualitative Disclosures About Market Risk and Note (3) of the Notes to Consolidated Financial Statements.

The investment results of the P&C Group for each of the past three years are shown in the following table:

Average
Invested
Investment
Percent Earned
Year Assets(a) Income(b) Before Tax After Tax
(in millions)

2011

$ 38,901 $ 1,562 4.02 % 3.25 %

2010

38,288 1,558 4.07 3.29

2009

36,969 1,549 4.19 3.39

(a)  Average of amounts with fixed maturity securities at amortized cost, equity securities at fair value and other invested assets, which include private equity limited partnerships carried at the P&C Group's equity in the net assets of the partnerships.
(b)  Investment income after deduction of investment expenses, but before applicable income tax.

Competition

There are numerous property and casualty insurance companies operating in the United States as well as in the international jurisdictions in which we write business. Accordingly, the property and casualty insurance industry is highly competitive both as to price and service. Members of the P&C Group compete not only with other stock companies but also with mutual companies, other underwriting organizations and alternative risk sharing mechanisms. Some competitors produce their business at a lower cost through the use of salaried personnel rather than independent agents and brokers. Rates are not uniform among insurers and vary according to the types of insurers, product coverage and methods of operation. The P&C Group competes for business not only on the basis of price, but also on the basis of financial strength, availability of coverage desired by customers and quality of service, including claim adjustment service. The P&C Group's products and services are generally designed to serve specific customer groups or needs and to offer a degree of customization that is of value to the insured. The P&C Group continues to work closely with its distribution network of agents and brokers as well as customers and to reinforce with them the stability, expertise and added value the P&C Group's products provide.

There are approximately 2,500 property and casualty insurance companies in the United States operating independently or in groups and no single company or group is dominant across all lines of business or jurisdictions. However, the relatively large size and underwriting capacity of the P&C Group provide it opportunities not available to smaller companies.

Regulation and Premium Rates

Chubb is a holding company with subsidiaries primarily engaged in the property and casualty insurance business. In the United States, Chubb and the companies within the P&C Group are subject to regulation by certain states as members of an insurance holding company system. All states have enacted legislation that regulates insurance holding company systems such as the Corporation. This legislation generally provides that each insurance company in the system is required to register with the department of insurance of its state of domicile and furnish information concerning the operations of companies within the holding company system that 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 equitable. Notice to the insurance commissioners is required

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prior to the consummation of transactions affecting the ownership or control of an insurer and of certain material transactions between an insurer and any person in its holding company system and, in addition, certain of such transactions cannot be consummated without the commissioners' prior approval. Recent amendments to the model holding company law and regulation adopted by the National Association of Insurance Commissioners (NAIC), if passed by the state legislatures, will require insurance holding company systems to provide regulators with more information about the risks posed by any non-insurance company subsidiaries in the holding company system.

Companies within the P&C Group are subject to regulation and supervision in the respective states in which they do business. In general, such regulation is designed to protect the interests of policyholders, and not necessarily the interests of insurers, their shareholders and other investors. The extent of such regulation varies but generally has its source in statutes that delegate regulatory, supervisory and administrative powers to a department of insurance.

State insurance departments impose regulations that, among other things, establish the standards of solvency that must be met and maintained. The NAIC has a risk-based capital requirement for property and casualty insurance companies. The risk-based capital formula is used by all state regulatory authorities to identify insurance companies that may be undercapitalized and that merit further regulatory attention. The formula 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 policyholders' surplus to its minimum capital requirement will determine whether any state regulatory action is required. At December 31, 2011, each member of the P&C Group had more than sufficient capital to meet the risk-based capital requirement. The NAIC periodically reviews the risk-based capital formula and changes to the formula could be considered in the future. The NAIC recently has undertaken a Solvency Modernization Initiative focused on updating the U.S. insurance solvency regulation framework, including capital requirements, governance and risk management, group supervision, accounting and financial reporting and reinsurance. Among the changes under consideration by the NAIC is implementation of an Own Risk and Solvency Assessment (ORSA) rule that would require insurers to measure and share with solvency regulators their internal assessment of capital needs for the entire holding company group, including non-insurance subsidiaries.

State insurance departments also administer other aspects of insurance regulation and supervision that affect the P&C Group's operations including: the licensing of insurers and their agents; restrictions on insurance policy terminations; unfair trade practices; the nature of and limitations on investments; premium rates; restrictions on the size of risks that may be insured under a single policy; deposits of securities for the benefit of policyholders; approval of policy forms; periodic examinations of the affairs of insurance companies; annual and other reports required to be filed on the financial condition of companies or for other purposes; limitations on dividends to policyholders and shareholders; and the adequacy of provisions for unearned premiums, unpaid losses and loss adjustment expenses, both reported and unreported, and other liabilities.

Regulatory requirements applying to premium rates vary from state to state, but generally provide that rates cannot be excessive, inadequate or unfairly discriminatory. In many states, these regulatory requirements can impact the P&C Group's ability to change rates, particularly with respect to personal lines products such as automobile and homeowners insurance, without prior regulatory approval. For example, in certain states there are measures that limit the use of catastrophe models or credit scoring in ratemaking and, at times, some states have adopted premium rate freezes or rate rollbacks. State limitations on the ability to cancel or nonrenew certain policies also can affect the P&C Group's ability to charge adequate rates.

Subject to legislative and regulatory requirements, the P&C Group's management determines the prices charged for its policies based on a variety of factors including loss and loss adjustment expense experience, inflation, anticipated changes in the legal environment, both judicial and legislative, and tax law and rate changes. Methods for arriving at prices vary by type of business, exposure assumed and size of risk. Underwriting profitability is affected by the accuracy of these assumptions, by the willingness of

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insurance regulators to approve changes in those rates that they control and by certain other matters, such as underwriting selectivity and expense control.

In all states, insurers authorized to transact certain classes of property and casualty insurance are required to become members of an insolvency fund. In the event of the insolvency of a licensed insurer writing a class of insurance covered by the fund in the state, companies in the P&C Group, together with the other fund members, are assessed in order to provide the funds necessary to pay certain claims against the insolvent insurer. Generally, fund assessments are proportionately based on the members' written premiums for the classes of insurance written by the insolvent insurer. In certain states, the P&C Group can recover a portion of these assessments through premium tax offsets or policyholder surcharges. In 2011, assessments of the members of the P&C Group were insignificant. The amount of future assessments cannot be reasonably estimated and can vary significantly from year to year.

Insurance regulation in certain states requires the companies in the P&C Group, together with other insurers operating in the state, to participate in assigned risk plans, reinsurance facilities and joint underwriting associations, which are mechanisms that generally provide applicants with various basic insurance coverages when they are not available in voluntary markets. Such mechanisms are most prevalent for automobile and workers' compensation insurance, but a majority of states also mandate that insurers, such as the P&C Group, participate in Fair Plans or Windstorm Plans, which offer basic property coverages to insureds where not otherwise available. Some states also require insurers to participate in facilities that provide homeowners, crime and other classes of insurance where periodic market constrictions may occur. Participation is based upon the amount of a company's voluntary written premiums in a particular state for the classes of insurance involved. These involuntary market plans generally are underpriced and produce unprofitable underwriting results.

In several states, insurers, including members of the P&C Group, participate in market assistance plans. Typically, a market assistance plan is voluntary, of limited duration and operates under the supervision of the insurance commissioner to provide assistance to applicants unable to obtain commercial and personal liability and property insurance. The assistance may range from identifying sources where coverage may be obtained to pooling of risks among the participating insurers. A few states require insurers, including members of the P&C Group, to purchase reinsurance from a mandatory reinsurance fund.

Although the federal government and its regulatory agencies generally do not directly regulate the business of insurance, federal initiatives often have an impact on the business in a variety of ways. Under the Dodd-Frank Wall Street Reform and Consumer Protection Act, signed into law in July 2010, two federal government bodies, the Federal Insurance Office (FIO) and the Financial Stability Oversight Council (FSOC), were created which may impact the regulation of insurance. Although the FIO is prohibited from directly regulating the business of insurance, it has authority to represent the United States in international insurance matters and has limited powers to preempt certain types of state insurance laws. The FIO also can recommend to the FSOC that it designate an insurer as an entity posing risks to U.S. financial stability in the event of the insurer's material financial distress or failure. An insurer so designated by FSOC could be subject to Federal Reserve supervision and heightened prudential standards. Other current and proposed federal measures that may significantly affect the P&C Group's business and the market as a whole include those concerning federal terrorism insurance, tort law, natural catastrophes, corporate governance, ergonomics, health care reform including the containment of medical costs, privacy, e-commerce, international trade, federal regulation of insurance companies and the taxation of insurance companies.

Companies in the P&C Group are also affected by a variety of state and federal legislative and regulatory measures as well as by decisions of their courts that define and extend the risks and benefits for which insurance is provided. These include: redefinitions of risk exposure in areas such as water damage, including mold, flood and storm surge; products liability and commercial general liability; credit scoring; and extension and protection of employee benefits, including workers' compensation and disability benefits.

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Outside the United States, the extent of insurance regulation varies significantly among the countries in which the P&C Group operates, and regulatory and political developments in international markets could impact the P&C Group's business. Some countries have minimal regulatory requirements, while others regulate insurers extensively. Foreign insurers in many countries are subject to greater restrictions than domestic competitors. In certain countries, the P&C Group has incorporated insurance subsidiaries locally to improve its competitive position. Regulators in many countries are working with the International Association of Insurance Supervisors (IAIS) to consider changes to insurance company solvency standards and group supervision of companies in a holding company system, including noninsurance companies. These IAIS initiatives include a set of Insurance Core Principles (ICPs) for a globally-accepted framework for insurance sector regulation and supervision and the Common Framework for the Supervision of Internationally Active Insurance Groups (ComFrame). The European Union Solvency II directive, being implemented to harmonize insurance regulation across the European Union member states, will require regulated companies such as the P&C Group's European operations to meet new requirements in relation to risk and capital management. Solvency II is scheduled to be effective January 1, 2013, but will not be fully enforced until January 1, 2014.

Legislative and judicial developments pertaining to asbestos and toxic waste exposures are discussed in the Property and Casualty Insurance - Loss Reserves section of MD&A.

Real Estate

The Corporation's wholly owned subsidiary, Bellemead Development Corporation (Bellemead), and its subsidiaries were involved in commercial development activities primarily in New Jersey and residential development activities primarily in central Florida. The real estate operations are in runoff.

Chubb Financial Solutions

Chubb Financial Solutions (CFS) provided customized financial products, primarily derivative financial instruments, to corporate clients. CFS has been in runoff since 2003. Since that date, CFS has terminated early or run off nearly all of its contractual obligations within its financial products portfolio. Additional information related to CFS's operations is included in the Corporate and Other - Chubb Financial Solutions section of MD&A.

Item 1A. Risk Factors

The Corporation's business is subject to a number of risks, including those described below, that could have a material effect on the Corporation's results of operations, financial condition or liquidity and that could cause our operating results to vary significantly from period to period. References to "we," "us" and "our" appearing in this Form 10-K should be read to refer to the Corporation.

If our property and casualty loss reserves are insufficient, our results could be adversely affected.

The process of establishing loss reserves is complex and imprecise because it must take into consideration many variables that are subject to the outcome of future events. As a result, informed subjective estimates and judgments as to our ultimate exposure to losses are an integral component of our loss reserving process. Variations between our loss reserve estimates and the actual emergence of losses could be material and could have a material adverse effect on our results of operations or financial condition.

A further discussion of the risk factors related to our property and casualty loss reserves is presented in the Property and Casualty Insurance - Loss Reserves section of MD&A.

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

As industry practices and legal, judicial, social, environmental and other conditions change, unexpected or unintended issues related to claims and coverage may emerge. These issues may adversely

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affect our business by either extending coverage beyond our underwriting intent or by increasing the number or size of claims. In some instances, these issues may not become apparent for some time after we have written the insurance policies that are affected by such issues. As a result, the full extent of liability under our insurance policies may not be known for many years after the policies are issued. Emerging claim and coverage issues could have a material adverse effect on our results of operations or financial condition.

Catastrophe losses could materially and adversely affect our business.

As a property and casualty insurance holding company, our insurance operations expose us to claims arising out of catastrophes. Catastrophes can be caused by various natural perils, including hurricanes and other windstorms, earthquakes, tsunamis, tidal waves, severe winter weather and brush fires. Catastrophes can also be man-made, such as a terrorist attack. The frequency and severity of catastrophes are inherently unpredictable. It is possible that both the frequency and severity of natural and man-made catastrophic events will increase.

The extent of losses from a catastrophe is a function of both the total amount of exposure under our insurance policies in the area affected by the event and the severity of the event. Most catastrophes are restricted to relatively small geographic areas; however, hurricanes and earthquakes may produce significant damage over larger areas, especially those that are heavily populated.

We are exposed to natural and man-made catastrophe risks in both our U.S. and international operations. Catastrophe risks include hurricanes and cyclones along the coastlines of North America, the Caribbean Region, Latin America, Asia and Australia. Catastrophe risks also include winter storms, northeasters, thunderstorms, hail storms, tornadoes, flooding and other water damage, earthquakes, other seismic or volcanic eruption, wildfires, and terrorism that may occur in locations in and outside the United States where we insure properties.

We utilize proprietary and third party catastrophe modeling tools to assist us in managing our catastrophe exposures. These models rely on various methodologies and assumptions which are subjective and subject to uncertainty. The methodologies and assumptions also may be changed from time to time by the third party modeling company. The use of different methodologies or assumptions would result in the model generating substantially different estimations of our catastrophe exposures. Moreover, modeled loss estimates may be materially different from actual results.

Natural or man-made catastrophic events could cause claims under our insurance policies to be higher than we anticipated and could cause substantial volatility in our financial results for any fiscal quarter or year. Our ability to write new business could also be affected. Increases in the value and geographic concentration of insured property and the effects of inflation could increase the severity of claims from catastrophic events in the future. In addition, states have from time to time passed legislation that has the effect of limiting the ability of insurers to manage catastrophe risk, such as legislation limiting insurers ability to increase rates and prohibiting insurers from withdrawing from catastrophe-exposed areas.

As a result of the foregoing, it is possible that the occurrence of any natural or man-made catastrophic event could have a material adverse effect on our business, results of operations, financial condition and liquidity. A further discussion of the risk factors related to catastrophes is presented in the Property and Casualty Insurance - Catastrophe Risk Management section of MD&A.

We cannot predict the impact that changing climate conditions, including legal, regulatory and social responses thereto, may have on our business.

Various scientists, environmentalists, international organizations, regulators and other commentators believe that global climate change has added, and will continue to add, to the unpredictability, frequency and severity of natural disasters (including, but not limited to, hurricanes, tornadoes, freezes, other storms and fires) in certain parts of the world. In response to this belief, a number of legal and

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regulatory measures as well as social initiatives have been introduced in an effort to reduce greenhouse gas and other carbon emissions which may be chief contributors to global climate change.

We cannot predict the impact that changing climate conditions, if any, will have on our results of operations or our financial condition. Moreover, we cannot predict how legal, regulatory and social responses to concerns about global climate change will impact our business.

We rely on pricing and capital models, but actual results could differ materially from the model outputs.

We employ various predictive modeling, stochastic modeling and/or forecasting techniques to analyze and estimate loss trends and the risks associated with our assets and liabilities. We utilize the modeled outputs and related analyses to assist us in making underwriting, pricing, reinsurance and capital decisions. The modeled outputs and related analyses are subject to numerous assumptions, uncertainties and the inherent limitations of any statistical analysis. Consequently, modeled results may differ materially from our actual experience. If, based upon these models or otherwise, we under price our products or underestimate the frequency and/or severity of loss events, our results of operations or financial condition may be adversely affected. If, based upon these models or otherwise, we over price our products or overestimate the risks we are exposed to, new business growth and retention of our existing business may be adversely affected which could have a material adverse effect on our results of operations.

We may experience reduced returns or losses on our investments especially during periods of heightened volatility, which could have a material adverse effect on our results of operations or financial condition.

The returns on our investment portfolio may be reduced or we may incur losses as a result of changes in general economic conditions, interest rates, real estate markets, fixed income markets, equity markets, alternative investment markets, credit markets, exchange rates, global capital market conditions and numerous other factors that are beyond our control.

During prolonged periods of low interest rates and investment returns, we may not be able to invest new money generated by our operations or reinvest funds at rates that generate the same level of investment income generated by our existing invested assets, which could have a material adverse effect on our results of operations and financial condition.

The worldwide financial markets experience high levels of volatility during certain periods, which could have an increasingly adverse impact on the U.S. and foreign economies. The financial market volatility and the resulting negative economic impact could continue and it is possible that it may be prolonged, which could adversely affect our current investment portfolio, make it difficult to determine the value of certain assets in our portfolio and/or make it difficult for us to purchase suitable investments that meet our risk and return criteria. These factors could cause us to realize less than expected returns on invested assets, sell investments for a loss or write off or write down investments, any of which could have a material adverse effect on our results of operations or financial condition.

A significant portion of our investment portfolio is invested in obligations of states, municipalities and political subdivisions (often referred to as municipal bonds). The recent financial market volatility and the resulting negative economic impact have resulted in actual or projected budget deficits for many municipal bond issuers. These deficits, combined with declining municipal tax bases and revenues, have raised concerns over the potential for an increased risk of default or impairment of municipal bonds. Such concerns, as well actual defaults or impairments, could adversely impact these investments in terms of volatility, liquidity and value.

Our investment portfolio includes commercial mortgage-backed securities, residential mortgage-backed securities, collateralized mortgage obligations and pass-through securities. Continuation of the

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prolonged stress in the U.S. housing market and/or financial market disruption could adversely impact these investments.

Our investment portfolio includes securities that may be more volatile than fixed maturity instruments and certain of these instruments may be illiquid.

Our investment portfolio includes equity securities and private equity limited partnership interests which may experience significant volatility in their investment returns and valuation. Moreover, our private equity limited partnership interests are subject to transfer restrictions and may be illiquid. If the investment returns or value of these investments decline, or if we are unable to dispose of these investments at their carrying value, it could have a material adverse effect on our results of operations or financial condition.

Changes to federal and/or state laws could adversely affect the value of our investment portfolio.

A significant portion of our investment portfolio consists of tax exempt securities and we receive certain tax benefits relating to such securities based on current laws and regulations. Our portfolio has also benefited from certain other laws and regulations, including without limitation, tax credits (such as foreign tax credits). Federal and/or state tax legislation could be enacted that would lessen or eliminate some or all of the tax advantages currently benefiting us and could negatively impact the value of our investment portfolio.

We are exposed to credit risk and foreign currency risk in our business operations and in our investment portfolio.

We are exposed to credit risk in several areas of our business operations, including, without limitation, credit risk relating to reinsurance, co-sureties on surety bonds, policyholders of certain of our insurance products, independent agents and brokers, issuers of securities, insurers of certain securities and certain other counterparties relating to our investment portfolio.

With respect to reinsurance coverages that we have purchased, our ability to recover amounts due from reinsurers may be affected by the creditworthiness and willingness to pay of the reinsurers. Although certain reinsurance we have purchased is collateralized, the collateral is exposed to credit risk of the counterparty that has guaranteed an investment return on such collateral.

It is customary practice in the surety business for multiple insurers to participate as co-sureties on large surety bonds, meaning that each insurer (each referred to as a co-surety) assumes its proportionate share of the risk and receives a corresponding percentage of the bond premium. Under these arrangements, the co-sureties' obligations are joint and several. Consequently, if a co-surety defaults on its obligations, the remaining co-surety or co-sureties are obligated to make up the shortfall to the beneficiary of the surety bond even though the non-defaulting co-sureties did not receive the premium for that portion of the risk. Therefore, we are subject to credit risk with respect to the insurers with whom we are co-sureties on surety bonds.

In accordance with industry practice, when insureds purchase our insurance products through independent agents and brokers, they generally pay the premiums to the agent or broker, which in turn is required to remit the collected premium to us. In many jurisdictions, we are deemed to have received payment upon the receipt of the payment by the agent or broker, regardless of whether the agent or broker actually remits payment to us. As a result, we assume credit risk associated with amounts due from independent agents and brokers.

The value of our investment portfolio is subject to credit risk from the issuers and/or guarantors of the securities in the portfolio, other counterparties in certain transactions and, for certain securities, insurers that guarantee specific issuer's obligations. Defaults by the issuer and, where applicable, an issuer's guarantor, insurer or other counterparties with regard to any of such investments could reduce our net investment income and net realized investment gains or result in investment losses.

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We report our financial results in U.S. dollars, but a significant amount of the business we write and expenses we incur outside the United States are denominated in currencies other than the U.S. dollar. In addition, a substantial portion of our investment portfolio is denominated in non-U.S. dollar currencies. As a result, changes in the strength of the U.S. dollar relative to these foreign currencies could adversely affect our results of operations and financial condition.

Our exposure to any of the above credit risks and foreign currency risk could have a material adverse effect on our results of operations or financial condition.

The failure of the risk mitigation strategies we utilize could have a material adverse effect on our financial condition or results of operations.

We utilize a number of strategies to mitigate our risk exposure, such as:

•  engaging in rigorous underwriting;
•  carefully evaluating terms and conditions of our policies;
•  focusing on our risk aggregations by geographic zones, industry type, credit exposure and other bases; and
•  ceding reinsurance.

However, there are inherent limitations in all of these tactics and no assurance can be given that an event or series of events will not result in loss levels in excess of our probable maximum loss models, which could have a material adverse effect on our financial condition or results of operations. It is also possible that losses could manifest themselves in ways that we do not anticipate and that our risk mitigation strategies are not designed to address. Such a manifestation of losses could have a material adverse effect on our financial condition or results of operations.

These risks may be heightened during difficult economic conditions such as those currently being experienced in the United States and elsewhere.

Reinsurance coverage may not be available to us in the future at commercially reasonable rates or at all.

The availability and cost of reinsurance are subject to prevailing market conditions that are beyond our control. No assurances can be made that reinsurance will remain continuously available to us in amounts that we consider sufficient and at rates that we consider acceptable, which would cause us to increase the amount of risk we retain, reduce the amount of business we underwrite or look for alternatives to reinsurance. This, in turn, could have a material adverse effect on our financial condition or results of operations.

Cyclicality of the property and casualty insurance industry may cause fluctuations in our results.

The property and casualty insurance business historically has been cyclical, experiencing periods characterized by intense price competition, relatively low premium rates and less restrictive underwriting standards followed by periods of relatively low levels of competition, high premium rates and more selective underwriting standards. We expect this cyclicality to continue. The periods of intense price competition in the cycle could adversely affect our financial condition, profitability or cash flows.

A number of factors, including many that are volatile and unpredictable, can have a significant impact on cyclical trends in the property and casualty insurance industry and the industry's profitability. These factors include:

•  an apparent trend of courts to grant increasingly larger awards for certain damages;
•  catastrophic hurricanes, windstorms, earthquakes and other natural disasters, as well as the occurrence of man-made disasters (e.g., a terrorist attack);

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•  availability, price and terms of reinsurance;
•  fluctuations in interest rates;
•  changes in the investment environment that affect market prices of and income and returns on investments; and
•  inflationary pressures that may tend to affect the size of losses experienced by insurance companies.

We cannot predict whether or when market conditions will improve, remain constant or deteriorate. Negative market conditions may impair our ability to write insurance at rates that we consider appropriate relative to the risk assumed. If we cannot write insurance at appropriate rates, our ability to transact business would be materially and adversely affected.

We may be unsuccessful in our efforts to sell new products and/or to expand our existing product offerings to new markets.

Our strategy for enhancing profitable growth includes new product initiatives as well as expanding existing product offerings to new markets. We may not be successful in these efforts, which could have a material adverse effect on our results of operations. If we are successful, results attributable to these product offerings could be different than we anticipate and could have an adverse effect on our results of operations or financial condition.

Payment of obligations under surety bonds could adversely affect our future operating results.

The surety business tends to be characterized by infrequent but potentially high severity losses. The majority of our surety obligations are intended to be performance-based guarantees. When losses occur, they may be mitigated, at times, by recovery rights to the customer's assets, contract payments, collateral and bankruptcy recoveries. We have substantial commercial and construction surety exposure for current and prior customers. In that regard, we have exposures related to surety bonds issued on behalf of companies that have experienced or may experience deterioration in creditworthiness. If the financial condition of these companies were adversely affected by the economy or otherwise, we may experience an increase in filed claims and may incur high severity losses, which could have a material adverse effect on our results of operations.

A downgrade in our credit ratings and financial strength ratings could adversely impact the competitive positions of our operating businesses.

Credit ratings and financial strength ratings can be important factors in establishing our competitive position in the insurance markets. There can be no assurance that our ratings will continue for any given period of time or that they will not be changed. If our credit ratings were downgraded in the future, we could incur higher borrowing costs and may have more limited means to access capital. In addition, a downgrade in our financial strength ratings could adversely affect the competitive position of our insurance operations, including a possible reduction in demand for our products in certain markets.

The inability of our insurance subsidiaries to pay dividends in sufficient amounts would harm our ability to meet our obligations and to pay future dividends.

As a holding company, Chubb relies primarily on dividends from its insurance subsidiaries to meet its obligations for payment of interest and principal on outstanding debt obligations and to pay dividends to shareholders. The ability of our insurance subsidiaries to pay dividends in the future will depend on their statutory surplus, on earnings and on regulatory restrictions. We are subject to regulation by some states as an insurance holding company system. Such regulation generally provides that transactions between companies within the holding company system must be fair and equitable. Transfers of assets among affiliated companies, certain dividend payments from insurance subsidiaries and certain material transactions between companies within the system may be subject to prior notice to, or prior approval

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by, state regulatory authorities. The ability of our insurance subsidiaries to pay dividends is also restricted by regulations that set standards of solvency that must be met and maintained, that limit investments and that limit dividends to shareholders. These regulations may affect Chubb's insurance subsidiaries' ability to provide Chubb with dividends.

Our businesses are heavily regulated, and changes in regulation may reduce our profitability and limit our growth.

Our insurance subsidiaries are subject to extensive regulation and supervision in the jurisdictions in which they conduct business. This regulation is generally designed to protect the interests of policyholders, and not necessarily the interests of insurers, their shareholders or other investors. The regulation relates to authorization for lines of business, capital and surplus requirements, investment limitations, underwriting limitations, transactions with affiliates, dividend limitations, changes in control, premium rates and a variety of other financial and nonfinancial components of an insurance company's business. Failure to comply with or to obtain appropriate authorizations and/or exemptions under any applicable laws and regulations 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.

Virtually all states in which we operate require the P&C Group, together with other insurers licensed to do business in that state, to bear a portion of the loss suffered by some insureds as the result of impaired or insolvent insurance companies. In addition, in various states, our insurance subsidiaries must participate in mandatory arrangements to provide various types of insurance coverage to individuals or other entities that otherwise are unable to purchase that coverage from private insurers. A few states require us to purchase reinsurance from a mandatory reinsurance fund. Such reinsurance funds can create a credit risk for insurers if not adequately funded by the state and, in some cases, the existence of a reinsurance fund could affect the prices charged for our policies. The effect of these and similar arrangements could reduce our profitability in any given period or limit our ability to grow our business.

In recent years, the state insurance regulatory framework has come under increased scrutiny, including scrutiny by federal officials, and some state legislatures have considered or enacted laws that may alter or increase state authority to regulate insurance companies and insurance holding companies. Further, the NAIC and state insurance regulators are continually reexamining existing laws and regulations, specifically focusing on modifications to statutory accounting principles, interpretations of existing laws and the development of new laws and regulations. The NAIC recently has undertaken a Solvency Modernization Initiative focused on updating the U.S. insurance solvency regulation framework, including capital requirements, governance and risk management, group supervision, accounting and financial reporting and reinsurance. Any proposed or future legislation or NAIC initiatives, if adopted, may be more restrictive on our ability to conduct business than current regulatory requirements or may result in higher costs or increased capital requirements.

Although the federal government and its regulatory agencies generally do not directly regulate the business of insurance, federal initiatives often have an impact on the business in a variety of ways. Current and proposed federal measures that may significantly affect the P&C Group's business and the market as a whole include measures concerning federal terrorism insurance, systemic risk regulation, tort law, natural catastrophes, corporate governance, ergonomics, health care reform including containment of medical costs, privacy, e-commerce, international trade, federal regulation of insurance companies and the taxation of insurance companies. Under the Dodd-Frank Wall Street Reform and Consumer Protection Act, signed into law in July 2010, two federal government bodies, the Federal Insurance Office (FIO) and the Financial Stability Oversight Council (FSOC), were created which may impact the regulation of insurance. Although the FIO is prohibited from directly regulating the business of insurance, it has authority to represent the United States in international insurance matters and has limited powers to preempt certain types of state insurance laws. The FIO also can recommend to the FSOC that it designate an insurer as an entity posing risks to U.S. financial stability in the event of the insurer's material financial distress or failure. An insurer so designated by FSOC could be subject to Federal Reserve supervision and heightened prudential standards. While we do not believe the P&C Group or any of its companies are systemically significant, it is possible the FSOC could conclude

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otherwise. If the FSOC were to designate the P&C Group or any of its insurance subsidiaries for supervision by the Federal Reserve, it could place more restrictions on our ability to conduct business and may result in higher costs, increased capital requirements and lower profitability. Even if an insurance company is not designated as a systemically important institution, it still could be adversely impacted by new rules governing such institutions, as non-bank financial institutions may, under certain circumstances, be subject to possible assessment to fund the orderly resolution of a financially distressed systemically important financial institution.

Our insurance subsidiaries also are subject to extensive regulation and supervision in jurisdictions outside the United States. Regulators in many countries are working with the International Association of Insurance Supervisors (IAIS) to consider changes to insurance company solvency standards and group supervision of companies in a holding company system, including noninsurance companies. Some IAIS initiatives are particularly focused on the supervision of internationally active insurance groups, such as the P&C Group. The European Union Solvency II directive will require regulated companies such as the P&C Group's European operations to meet new requirements in relation to risk and capital management. A U.S. parent of an European Union subsidiary could be subject to certain Solvency II requirements if the U.S. state-based regulatory system is not deemed "equivalent" to Solvency II. Solvency II is scheduled to be effective January 1, 2013 and will be fully enforced beginning January 1, 2014. Such proposed or future legislation and regulatory initiatives in countries where we operate, if adopted, may be more restrictive on our ability to conduct business than current regulatory requirements or may result in higher costs, increased capital requirements and lower profitability.

The IAIS also is working with the Financial Stability Board (FSB) to decide if any insurers should be designated globally significant financial institutions. While we do not believe the P&C Group or any of its companies are globally systemically significant institutions, it is possible the FSB could conclude otherwise. The ramifications of an FSB globally systemically significant designation for the P&C Group or any of its insurance subsidiaries is unknown at this time; however, it is likely to result in greater regulatory scrutiny and could place more restrictions on our ability to conduct business, result in higher costs, increased capital requirements or lower profitability.

Changes in accounting principles and financial reporting requirements may impact the manner in which we present our results of operations and financial condition.

The Financial Accounting Standards Board (FASB) and the Securities and Exchange Commission may issue from time to time new accounting and reporting standards or changes in the interpretation of existing standards. These new standards or changes in interpretation could have an effect on how we report our results of operations and financial condition in the future.

Intense competition for our products could harm our ability to maintain or increase our profitability and premium volume.

The property and casualty insurance industry is highly competitive. We compete not only with other stock companies but also with mutual companies, other underwriting organizations and alternative risk sharing mechanisms. We compete for business not only on the basis of price, but also on the basis of financial strength, availability of coverage desired by customers and quality of service, including claim adjustment service. We may have difficulty in continuing to compete successfully on any of these bases in the future.

If competition limits our ability to write new business at adequate rates, our results of operations could be adversely affected.

We are subject to a number of risks associated with our business outside the United States.

A significant portion of our business is conducted outside the United States, including in Asia, Australia, Canada, Europe and Latin America. By doing business outside the United States, we are subject to a number of risks, including without limitation, dealing with jurisdictions, especially in

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emerging markets, that may lack political, financial or social stability and/or a strong legal and regulatory framework, which may make it difficult to do business and comply with local laws and regulations in such jurisdictions. Failure to comply with local laws in a particular jurisdiction or doing business in a country that becomes increasingly unstable could have a significant adverse effect on our business and operations in that market as well as on our reputation generally.

As part of our international operations, we engage in transactions denominated in currencies other than the U.S. dollar. To reduce our exposure to currency fluctuation, we attempt to match the currency of the liabilities we incur under insurance policies with assets denominated in the same local currency. However, in the event that we underestimate our exposure, negative movements in the U.S. dollar versus the local currency will exacerbate the impact of the exposure on our results of operations and financial condition.

We report the results of our international operations on a consolidated basis with our domestic business. These results are reported in U.S. dollars. A significant portion of the business we write outside the United States, however, is transacted in local currencies. Consequently, fluctuations in the relative value of local currencies in which the policies are written versus the U.S. dollar can mask the underlying trends in our international business.

The United States and other jurisdictions in which we operate have adopted various laws and regulations that may apply to the business we conduct outside of the United States, including those relating to antibribery and economic sanctions compliance. Although we have policies and controls in place that are designed to ensure compliance with these laws and regulations, it is possible that an employee or intermediary could fail to comply with applicable laws and regulations. In such event, we could be exposed to civil penalties, criminal penalties and other sanctions. In addition, such violations could damage our business and/or our reputation. Such civil penalties, criminal penalties, other sanctions and damage to our business and/or reputation could have a material adverse effect on our results of operations or financial condition.

We are dependent on a distribution network comprised of independent insurance brokers and agents to distribute our products.

We generally do not use salaried employees to promote or distribute our insurance products. Instead, we rely on a large number of independent insurance brokers and agents. Accordingly, our business is dependent on the willingness of these brokers and agents to recommend our products to their customers. Deterioration in relationships with our broker and agent distribution network could materially and adversely affect our ability to sell our products, which, in turn, could have a material adverse effect on our results of operations or financial condition.

If we experience difficulties with outsourcing relationships, our ability to conduct our business might be negatively impacted.

We outsource certain business and administrative functions to third parties and may do so increasingly in the future. If we fail to develop and implement our outsourcing strategies or our third party providers fail to perform as anticipated, we may experience operational difficulties, increased costs and a loss of business that may have a material adverse effect on our results of operations or financial condition. By outsourcing certain business and administrative functions to third parties, we may be exposed to enhanced risk of data security breaches. Any breach of data security could damage our reputation and/or result in monetary damages, which, in turn, could have a material adverse effect on our results of operations or financial condition.

The occurrence of certain events could have a materially adverse effect on our systems and could impact our ability to conduct business effectively.

Our computer, information technology and telecommunications systems, which we use to conduct our business, interface with and rely upon third party systems. Systems failures or outages could

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compromise our ability to perform business functions in a timely manner, which could harm our ability to conduct business and hurt our relationships with our business partners and customers.

In the event of a disaster such as a natural catastrophe, an industrial accident, a blackout, a computer virus, a terrorist attack or war, our systems may be inaccessible to our employees, customers or business partners for an extended period of time. Even if our employees or third party providers are able to report to work, they might be unable to perform their duties for an extended period of time if our computer, information technology or telecommunication systems were disabled or destroyed.

Our systems could also be subject to physical break-ins, electronic hacking, and subject to similar disruptions from unauthorized tampering. This may impede or interrupt our business operations, which could have a material adverse effect on our results of operations or financial condition. In addition, such events could result in data security breaches. Any breach of data security could damage our reputation and/or result in monetary damages, which, in turn, could have a material adverse effect on our results of operations or financial condition.

Item 1B.   Unresolved Staff Comments

None.

Item 2.   Properties

The executive offices of the Corporation are in Warren, New Jersey. The administrative offices of the P&C Group are located in Warren and Whitehouse Station, New Jersey. The P&C Group maintains territory, branch and service offices in major cities throughout the United States and also has offices in Canada, Europe, Australia, Latin America and Asia. Office facilities are leased with the exception of buildings in Whitehouse Station, New Jersey and Simsbury, Connecticut. Management considers its office facilities suitable and adequate for the current level of operations.

Item 3.   Legal Proceedings

The information required with respect to Item 3 is included in Note (13)(a) of the Notes to Consolidated Financial Statements, which information is incorporated by reference into this Item 3.

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Executive Officers of the Registrant

Year of
Age(a) Election(b)

John D. Finnegan, Chairman, President and Chief Executive Officer

63 2002

W. Brian Barnes, Senior Vice President and Chief Actuary of Chubb & Son, a division of Federal

49 2008

Maureen A. Brundage, Executive Vice President and General Counsel

55 2005

Robert C. Cox, Executive Vice President of Chubb & Son, a division of Federal

53 2003

John J. Kennedy, Senior Vice President and Chief Accounting Officer

56 2008

Mark P. Korsgaard, Executive Vice President of Chubb & Son, a division of Federal

56 2010

Paul J. Krump, President of Commercial and Specialty Lines of Chubb & Son, a division of Federal 

52 2001

Harold L. Morrison, Jr., Executive Vice President, Chief Global Field Officer and Chief Administrative Officer of Chubb & Son, a division of Federal

54 2008

Steven R. Pozzi, Executive Vice President of Chubb & Son, a division of Federal

55 2009

Dino E. Robusto, President of Personal Lines and Claims of Chubb & Son, a division of Federal

53 2006

Richard G. Spiro, Executive Vice President and Chief Financial Officer

47 2008

Kathleen M. Tierney, Executive Vice President of Chubb & Son, a division of Federal

43 2010

(a)  Ages listed above are as of April 24, 2012.

(b) Date indicates year first elected or designated as an executive officer.

All of the foregoing officers serve at the pleasure of the Board of Directors of the Corporation and have been employees of the Corporation for more than five years except for Mr. Spiro.

Before joining the Corporation in 2008, Mr. Spiro was an investment banker at Citigroup Global Markets Inc., where he served as a Managing Director in Citigroup's financial institutions investment banking group.

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PART II.

Item 5.   Market for the Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

The common stock of Chubb is listed and principally traded on the New York Stock Exchange (NYSE) under the trading symbol "CB". The following are the high and low closing sale prices as reported on the NYSE Composite Tape and the quarterly dividends declared per share for each quarter of 2011 and 2010.

2011
First
Second
Third
Fourth
Quarter Quarter Quarter Quarter

Common stock prices

High

$ 61.31 $ 65.87 $ 64.45 $ 70.31

Low

57.32 60.50 55.43 58.12

Dividends declared

.39 .39 .39 .39

2010
First
Second
Third
Fourth
Quarter Quarter Quarter Quarter

Common stock prices

High

$ 52.47 $ 53.75 $ 58.14 $ 60.23

Low

47.66 49.10 49.20 56.05

Dividends declared

.37 .37 .37 .37

At February 10, 2012, there were approximately 8,000 common shareholders of record.

The declaration and payment of future dividends to Chubb's shareholders will be at the discretion of Chubb's Board of Directors and will depend upon many factors, including the Corporation's operating results, financial condition and capital requirements, and the impact of regulatory constraints discussed in Note (17)(e) of the Notes to Consolidated Financial Statements.

The following table summarizes Chubb's repurchases of its common stock during each month in the quarter ended December 31, 2011.

Total Number of
Maximum Number of
Total
Shares Purchased as
Shares that May Yet Be
Number of
Part of Publicly
Purchased Under
Shares
Average Price
Announced Plans or
the Plans or
Period Purchased(a) Paid Per Share Programs Programs(b)

October 2011

443,900 $ 58.70 443,900 6,461,380

November 2011

2,795,903 65.37 2,795,903 3,665,477

December 2011

2,756,070 68.04 2,756,070 909,407

Total

5,995,873 66.10 5,995,873

(a)  The stated amounts exclude 2,050 shares and 227 shares delivered to Chubb during the months of October 2011 and December 2011, respectively, by employees of the Corporation to cover option exercise prices in connection with the Corporation's stock-based compensation plans.

(b)  On December 9, 2010, the Board of Directors authorized the repurchase of up to 30,000,000 shares of Chubb's common stock. On January 26, 2012, the Board of Directors authorized the repurchase of up to $1.2 billion of Chubb's common stock. These authorizations have no expiration date.

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Stock Performance Graph

The following performance graph compares the performance of Chubb's common stock during the five-year period from December 31, 2006 through December 31, 2011 with the performance of the Standard & Poor's 500 Index and the Standard & Poor's Property & Casualty Insurance Index. The graph plots the changes in value of an initial $100 investment over the indicated time periods, assuming all dividends are reinvested.

Cumulative Total Return
Based upon an initial investment of $100 on December 31, 2006
with dividends reinvested

December 31
2006 2007 2008 2009 2010 2011

Chubb

$ 100 $ 105 $ 101 $ 101 $ 125 $ 149

S&P 500

100 105 66 84 97 99

S&P 500 Property & Casualty Insurance

100 86 61 68 74 74

Our filings with the Securities and Exchange Commission (SEC) may incorporate information by reference, including this Form 10-K. Unless we specifically state otherwise, the information under this heading "Stock Performance Graph" shall not be deemed to be "soliciting materials" and shall not be deemed to be "filed" with the SEC or incorporated by reference into any of our filings under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended.

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Item 6.   Selected Financial Data

2011 2010 2009 2008 2007
(in millions except for per share amounts)

FOR THE YEAR

Revenues

Property and Casualty Insurance

Premiums Earned

$ 11,644 $ 11,215 $ 11,331 $ 11,828 $ 11,946

Investment Income

1,598 1,590 1,585 1,652 1,622

Other Revenues

- - 2 4 11

Corporate and Other

55 88 75 108 154
Realized Investment Gains
(Losses), Net
288 426 23 (371 ) 374

Total Revenues

$ 13,585 $ 13,319 $ 13,016 $ 13,221 $ 14,107

Income

Property and Casualty Insurance

Underwriting Income

$ 574 $ 1,222 $ 1,631 $ 1,361 $ 2,116

Investment Income

1,562 1,558 1,549 1,622 1,590

Other Income (Charges)

21 2 (3 ) 9 6
Property and Casualty
Insurance Income
2,157 2,782 3,177 2,992 3,712

Corporate and Other

(246 ) (220 ) (238 ) (214 ) (149 )
Realized Investment Gains
(Losses), Net
288 426 23 (371 ) 374

Income Before Income Tax

2,199 2,988 2,962 2,407 3,937

Federal and Foreign Income Tax

521 814 779 603 1,130

Net Income

$ 1,678 $ 2,174 $ 2,183 $ 1,804 $ 2,807

Per Share

Net Income

$ 5.76 $ 6.76 $ 6.18 $ 4.92 $ 7.01
Dividends Declared on
Common Stock
1.56 1.48 1.40 1.32 1.16

AT DECEMBER 31

Total Assets

$ 50,865 $ 50,249 $ 50,449 $ 48,429 $ 50,574

Long Term Debt

3,575 3,975 3,975 3,975 3,460

Total Shareholders' Equity

15,574 15,530 15,634 13,432 14,445

Book Value Per Share

57.15 52.24 47.09 38.13 38.56

25

Item 7.   Management's Discussion and Analysis of Financial Condition and Results of Operations

Management's Discussion and Analysis of Financial Condition and Results of Operations addresses the financial condition of the Corporation as of December 31, 2011 compared with December 31, 2010 and the results of operations for each of the three years in the period ended December 31, 2011. This discussion should be read in conjunction with the consolidated financial statements and related notes and the other information contained in this report.

INDEX

PAGE

Cautionary Statement Regarding Forward-Looking Information

27

Critical Accounting Estimates and Judgments

28

Overview

29

Property and Casualty Insurance

30

Underwriting Operations

31

Underwriting Results

31

Net Premiums Written

31

Reinsurance Ceded

32

Profitability

34

Review of Underwriting Results by Business Unit

35

Personal Insurance

35

Commercial Insurance

37

Specialty Insurance

39

Reinsurance Assumed

40

Catastrophe Risk Management

40

Natural Catastrophes

41

Terrorism Risk and Legislation

41

Loss Reserves

42

Estimates and Uncertainties

44

Reserves Other than Those Relating to Asbestos and Toxic Waste Claims

44

Reserves Relating to Asbestos and Toxic Waste Claims

48

Asbestos Reserves

49

Toxic Waste Reserves

52

Reinsurance Recoverable

53

Prior Year Loss Development

53

Investment Results

57

Other Income and Charges

57

Corporate and Other

58

Chubb Financial Solutions

58

Realized Investment Gains and Losses

58

Capital Resources and Liquidity

60

Capital Resources

60

Ratings

61

Liquidity

61

Contractual Obligations and Off-Balance Sheet Arrangements

63

Invested Assets

64

Fair Values of Financial Instruments

65

Pension and Other Postretirement Benefits

66

Accounting Pronouncements Not Yet Adopted

66

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION

Certain statements in this document are "forward-looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995 (PSLRA). These forward-looking statements are made pursuant to the safe harbor provisions of the PSLRA and include statements regarding our loss reserve and reinsurance recoverable estimates; asbestos and toxic waste liabilities and related developments; the number and severity of surety-related claims; the impact of an improving economy on our business; the impact of changes to our reinsurance program in 2011 and the cost of reinsurance in 2012; the adequacy of the rates at which we renewed and wrote new business; premium volume, pricing and competition in 2012; actions we may take in connection with our estimates of our exposure to catastrophes; property and casualty investment income during 2012; cash flows generated by our fixed income investments; currency rate fluctuations; estimates with respect to our credit derivatives exposure; the repurchase of common stock under our share repurchase program; our capital adequacy and funding of liquidity needs; the expected impact of new guidance related to accounting for costs associated with acquiring or renewing insurance contracts; the funding and timing of loss payments; and the redemption of our capital securities. Forward-looking statements are made based upon management's current expectations and beliefs concerning trends and future developments and their potential effects on us. These statements are not guarantees of future performance. Actual results may differ materially from those suggested by forward-looking statements as a result of risks and uncertainties, which include, among others, those discussed or identified from time to time in our public filings with the Securities and Exchange Commission and those associated with:

•  global political conditions and the occurrence of terrorist attacks, including any nuclear, biological, chemical or radiological events;
•  the effects of the outbreak or escalation of war or hostilities;
•  premium pricing and profitability or growth estimates overall or by lines of business or geographic area, and related expectations with respect to the timing and terms of any required regulatory approvals;
•  adverse changes in loss cost trends;
•  our ability to retain existing business and attract new business;
•  our expectations with respect to cash flow and investment income and with respect to other income;
•  the adequacy of loss reserves, including:

•  our expectations relating to reinsurance recoverables;
•  the willingness of parties, including us, to settle disputes;
•  developments in judicial decisions or regulatory or legislative actions relating to coverage and liability, in particular, for asbestos, toxic waste and other mass tort claims;
•  development of new theories of liability;
•  our estimates relating to ultimate asbestos liabilities; and
•  the impact from the bankruptcy protection sought by various asbestos producers and other related businesses;

•  the availability and cost of reinsurance coverage;
•  the occurrence of significant weather-related or other natural or human-made disasters, particularly in locations where we have concentrations of risk;
•  the impact of economic factors on companies on whose behalf we have issued surety bonds, and in particular, on those companies that file for bankruptcy or otherwise experience deterioration in creditworthiness;

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•  the effects of disclosures by, and investigations of, companies relating to possible accounting irregularities, practices in the financial services industry, investment losses or other corporate governance issues, including:

•  the effects on the capital markets and the markets for directors and officers and errors and omissions insurance;
•  claims and litigation arising out of actual or alleged accounting or other corporate malfeasance by other companies;
•  claims and litigation arising out of practices in the financial services industry;
•  claims and litigation relating to uncertainty in the credit and broader financial markets; and
•  legislative or regulatory proposals or changes;

•  the effects of changes in market practices in the U.S. property and casualty insurance industry arising from any legal or regulatory proceedings, related settlements and industry reform, including changes that have been announced and changes that may occur in the future;
•  the impact of legislative, regulatory and similar developments on our business, including those relating to terrorism, catastrophes, the financial markets, solvency standards, capital requirements and accounting guidance;
•  any downgrade in our claims-paying, financial strength or other credit ratings;
•  the ability of our subsidiaries to pay us dividends;
•  general political, economic and market conditions, whether globally or in the markets in which we operate, including:

•  changes in interest rates, market credit spreads and the performance of the financial markets;
•  currency fluctuations;
•  the effects of inflation;
•  changes in domestic and foreign laws, regulations and taxes;
•  changes in competition and pricing environments;
•  regional or general changes in asset valuations;
•  the inability to reinsure certain risks economically; and
•  changes in the litigation environment;

•  our ability to implement management's strategic plans and initiatives.

Chubb assumes no obligation to update any forward-looking information set forth in this document, which speak as of the date hereof.

CRITICAL ACCOUNTING ESTIMATES AND JUDGMENTS

The consolidated financial statements include amounts based on informed estimates and judgments of management for transactions that are not yet complete. Such estimates and judgments affect the reported amounts in the financial statements. Those estimates and judgments that were most critical to the preparation of the financial statements involved the determination of loss reserves and the recoverability of related reinsurance recoverables and the evaluation of whether a decline in value of any investment is temporary or other than temporary. These estimates and judgments, which are discussed within the following analysis of our results of operations, require the use of assumptions about matters that are highly uncertain and therefore are subject to change as facts and circumstances develop. If different estimates and judgments had been applied, materially different amounts might have been reported in the financial statements.

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OVERVIEW

The following highlights do not address all of the matters covered in the other sections of Management's Discussion and Analysis of Financial Condition and Results of Operations or contain all of the information that may be important to Chubb's shareholders or the investing public. This overview should be read in conjunction with the other sections of Management's Discussion and Analysis of Financial Condition and Results of Operations.

•  Net income was $1.7 billion in 2011 and $2.2 billion in both 2010 and 2009. The decrease in net income in 2011 compared with 2010 was due primarily to lower operating income and, to a lesser extent, lower net realized investment gains. Net income was similar in 2010 and 2009 as lower operating income in 2010 was offset by higher net realized investment gains. We define operating income as net income excluding realized investment gains and losses after tax.
•  Operating income was $1.5 billion in 2011, $1.9 billion in 2010 and $2.2 billion in 2009. The lower operating income in 2011 compared with that in 2010 and in 2010 compared with that in 2009 was due to lower underwriting income in our property and casualty insurance business, attributable in large part to an increasingly higher impact of catastrophes. Property and casualty investment income was flat in 2011 and increased slightly in 2010 compared with the respective prior year. Management uses operating income, a non-GAAP financial measure, among other measures, to evaluate its performance because the realization of investment gains and losses in any period could be discretionary as to timing and can fluctuate significantly, which could distort the analysis of operating trends.
•  Underwriting results were profitable in 2011 and highly profitable in both 2010 and 2009. Our combined loss and expense ratio was 95.3% in 2011 compared with 89.3% in 2010 and 86.0% in 2009. The less profitable results in 2011 and 2010 compared to the respective prior year were primarily due to a substantially higher impact of catastrophes. The impact of catastrophes accounted for 8.9 percentage points of the combined ratio in 2011 compared with 5.7 percentage points in 2010 and 0.8 of a percentage point in 2009.
•  During 2011, 2010 and 2009, we experienced overall favorable development of $767 million, $746 million and $762 million, respectively, on loss reserves established as of the previous year end. The favorable development in 2011 and 2010 was due primarily to favorable loss experience in certain professional liability, commercial liability and personal insurance classes. The favorable development in 2009 was due primarily to favorable loss experience in certain professional liability and commercial liability classes as well as lower than expected emergence of losses in the homeowners and commercial property classes.
•  Total net premiums written increased by 5% in 2011 and 1% in 2010. Premium growth in 2010 was limited by the general economic downturn, especially in the United States. Growth in 2011 in the United States benefited from positive pricing trends in the standard commercial market as well as improving general economic conditions. Premium growth in both years benefited slightly from the impact of currency fluctuation on business written outside the United States. Net premiums written in the United States increased by 2% in 2011 and decreased by 1% in 2010. Net premiums written outside the United States increased by 11% in 2011 and 9% in 2010. Measured in local currencies, premiums outside the United States grew significantly in 2011 and modestly in 2010. In both years, overall premium growth reflected our emphasis on underwriting discipline in a highly competitive market.
•  Property and casualty investment income after tax was flat in 2011 and increased by 1% in 2010 in what continued to be a low yield investment environment. The increase in 2010 reflected the positive effect of currency fluctuation on income from our investments denominated in currencies other than the U.S. dollar. Management uses property and casualty investment income after tax, a non-GAAP financial measure, to evaluate its investment results because it reflects the impact of any change in the proportion of the investment portfolio invested in tax exempt

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securities and is therefore more meaningful for analysis purposes than investment income before income tax.

•  Net realized investment gains before tax were $288 million ($187 million after tax) in 2011 compared with $426 million ($277 million after tax) in 2010 and $23 million ($15 million after tax) in 2009. The net realized gains in 2011 and 2010 were primarily related to investments in limited partnerships, which generally are reported on a quarter lag.

A summary of our consolidated net income is as follows:

Years Ended December 31
2011 2010 2009
(in millions)

Property and casualty insurance

$ 2,157 $ 2,782 $ 3,177

Corporate and other

(246 ) (220 ) (238 )

Consolidated operating income before income tax

1,911 2,562 2,939

Federal and foreign income tax

420 665 771

Consolidated operating income

1,491 1,897 2,168

Realized investment gains after income tax

187 277 15

Consolidated net income

$ 1,678 $ 2,174 $ 2,183

PROPERTY AND CASUALTY INSURANCE

A summary of the results of operations of our property and casualty insurance business is as follows:

Years Ended December 31
2011 2010 2009
(in millions)

Underwriting

Net premiums written

$ 11,758 $ 11,236 $ 11,077

Decrease (increase) in unearned premiums

(114 ) (21 ) 254

Premiums earned

11,644 11,215 11,331

Losses and loss expenses

7,407 6,499 6,268

Operating costs and expenses

3,695 3,496 3,377

Decrease (increase) in deferred policy acquisition costs

(63 ) (30 ) 27

Dividends to policyholders

31 28 28

Underwriting income

574 1,222 1,631

Investments

Investment income before expenses

1,598 1,590 1,585

Investment expenses

36 32 36

Investment income

1,562 1,558 1,549

Other income (charges)

21 2 (3 )

Property and casualty income before tax

$ 2,157 $ 2,782 $ 3,177

Property and casualty investment income after tax

$ 1,265 $ 1,261 $ 1,252

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Property and casualty income before tax was lower in 2011 than in 2010, which in turn was lower than in 2009. The successively lower level of income was due to a decrease in underwriting income. The decrease in underwriting income in 2011 compared with 2010 was primarily the result of a higher impact of catastrophes during 2011 and a decrease in current accident year underwriting profitability excluding the impact of catastrophes. The decrease in underwriting income in 2010 compared with 2009 was primarily attributable to a higher impact of catastrophes during 2010, offset in part by a modest improvement in current accident year underwriting profitability excluding the impact of catastrophes. Investment income in 2011 was flat and was slightly higher in 2010 compared with the respective prior year.

The profitability of our property and casualty insurance business depends on the results of both our underwriting and investment operations. We view these as two distinct operations since the underwriting functions are managed separately from the investment function. Accordingly, in assessing our performance, we evaluate underwriting results separately from investment results.

Underwriting Operations

Underwriting Results

We evaluate the underwriting results of our property and casualty insurance business in the aggregate and also for each of our separate business units.

Net Premiums Written

Net premiums written amounted to $11.8 billion in 2011, $11.2 billion in 2010 and $11.1 billion in 2009.

Net premiums written by business unit were as follows:

Years Ended December 31
% Increase
% Increase
2011 2011 vs. 2010 2010 2010 vs. 2009 2009
(dollars in millions)

Personal insurance

$ 3,977 4 % $ 3,825 5 % $ 3,657

Commercial insurance

5,051 8 4,676 - 4,660

Specialty insurance

2,720 - 2,727 - 2,739

Total insurance

11,748 5 11,228 2 11,056

Reinsurance assumed

10 * 8 * 21

Total

$ 11,758 5 $ 11,236 1 $ 11,077

*   The change in net premiums written is not presented since this business is in runoff.

Net premiums written increased by 5% in 2011 compared with 2010 and increased 1% in 2010 compared with 2009. Premiums written in the United States, which we define as premiums for U.S.-based exposures and which in 2011 represented about 72% of our total net premiums, increased by 2% in 2011 and decreased by 1% in 2010. Premiums written outside the United States, expressed in U.S. dollars, increased by 11% in 2011 and 9% in 2010. In both 2011 and 2010, the increase in net premiums written outside the United States included the positive impact of foreign currency fluctuation due to the impact of the weaker U.S. dollar relative to several currencies in which we wrote business in 2011 and 2010 compared to the respective prior year. As a result, overall premium growth in both 2011 and 2010 benefited slightly from the impact of currency fluctuation on business written outside the United States. Measured in local currencies, net premiums written outside the United States grew in both years, but more significantly in 2011. We experienced particularly strong growth in our personal insurance business outside the United States in both years. The countries outside the United States which were significant contributors to net premiums written in recent years were the United Kingdom, Canada, Brazil, Australia and Germany.

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Premium growth continued to be constrained in both 2011 and 2010 by the general economic conditions in recent years. The amounts of coverage purchased or the insured exposures, both of which are bases upon which we calculate the premiums we charge, were down slightly or were flat for many classes of business in both 2011 and 2010 compared to the respective prior year. Also, in both 2011 and 2010, our ability to grow premiums was constrained by our emphasis on underwriting discipline in the highly competitive market environment. In 2010, the competitive environment placed pressure on renewal rates, resulting in overall average U.S. renewal rates in the personal, commercial and professional liability businesses being down slightly compared to 2009. While the market remained competitive in 2011, the pricing environment improved steadily during the year, primarily in the commercial classes. Overall average U.S. renewal rates in the commercial business in 2011 were up slightly while rates in the professional liability business were down slightly. Average renewal rates for our personal auto and homeowners business were close to flat.

In 2011 and 2010, we retained a high percentage of our existing customers and renewed those accounts at what we believe are acceptable rates relative to the risks. Overall, the percentage of business we retained on renewal was similar in 2011 compared with 2010. In both years, the slow improvement in the economic environment and the highly competitive market continued to make it challenging to obtain new business at acceptable rates. The overall level of new business improved slightly in 2011 compared with 2010, as an increase in new personal and commercial business, driven by business written outside the United States, was mostly offset by a modest decline in new professional liability business. The overall level of new business also improved slightly in 2010 over 2009 levels, as a modest increase in new commercial business was offset to a small extent by a decline in new professional liability business.

The highly competitive market is likely to continue in 2012. Nevertheless, we expect that the positive pricing environment experienced in 2011, particularly in the commercial classes, will continue into 2012. In addition, there were some signs during 2011 that the economy was improving, which if it continues and is sustained, should have a positive impact on premiums, although there is typically a lag between a recovery and any resulting growth in premiums. We expect our net written premiums will be modestly higher in 2012 compared with 2011, assuming average foreign currency to U.S. dollar exchange rates in 2012 remain similar to 2011 year-end levels.

The reinsurance assumed business has been in runoff since the sale of our ongoing reinsurance assumed business in December 2005.

Reinsurance Ceded

Our premiums written are net of amounts ceded to reinsurers who assume a portion of the risk under the insurance policies we write that are subject to reinsurance. Most of our ceded reinsurance arrangements consist of excess of loss and catastrophe contracts that protect against a specified part or all of certain types of losses over stipulated amounts arising from any one occurrence or event. Therefore, unless we incur losses that exceed our initial retention under these contracts, we do not receive any loss recoveries. As a result, in certain years, we cede premiums to reinsurance companies and receive few, if any, loss recoveries. However, in a year in which there is a significant catastrophic event or a series of large individual losses, we may receive substantial loss recoveries. The impact of ceded reinsurance on net premiums written and net premiums earned and on net losses and loss expenses incurred for the three years ended December 31, 2011 is presented in Note (9) of the Notes to Consolidated Financial Statements.

The most significant component of our ceded reinsurance program is property reinsurance. We purchase two main types of property reinsurance: catastrophe and property per risk.

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For property risks in the United States and Canada, we purchase traditional catastrophe reinsurance, including our primary treaty which we refer to as our North American catastrophe treaty, as well as supplemental catastrophe reinsurance that provides additional coverage for our exposures in the northeastern United States. For certain exposures in the United States, we also have arranged for the purchase of multi-year, collateralized reinsurance funded through the issuance of collateralized risk linked securities, known as catastrophe bonds. For events outside the United States, we also purchase traditional catastrophe reinsurance.

The North American catastrophe treaty has an initial retention of $500 million and provides coverage for United States and Canadian exposures of approximately 64% of losses (net of recoveries from other available reinsurance) between $500 million and $1.65 billion. For catastrophic events in the northeastern part of the United States and in Florida, the North American catastrophe treaty, supplemental catastrophe reinsurance and/or the catastrophe bond arrangements provide additional coverages as discussed below.

The catastrophe bond arrangements generally provide reinsurance coverage for specific types of losses in specific geographic locations. They are generally designed to supplement coverage provided under the North American catastrophe treaty. We currently have two catastrophe bond arrangements in effect: a $150 million reinsurance arrangement that expires in March 2012 that provides coverage for homeowners-related hurricane losses in Florida and a $475 million reinsurance arrangement, a portion of which expires in March 2014 and the remainder in March 2015, that provides coverage for homeowners and commercial exposures for loss events in the northeastern United States.

For catastrophic events in the northeastern United States, the combination of the North American catastrophe treaty, the supplemental catastrophe reinsurance and the $475 million catastrophe bond arrangement provides additional coverage of approximately 64% of losses (net of recoveries from other available reinsurance) between $1.65 billion and $3.55 billion.

For hurricane events in Florida, we have reinsurance from the Florida Hurricane Catastrophe Fund (FHCF), which is a state-mandated fund designed to reimburse insurers for a portion of their residential catastrophic hurricane losses. Our participation in this mandatory program limits our initial retention in Florida for homeowners-related losses to approximately $160 million and provides coverage of 90% of covered losses between approximately $160 million and $570 million. Additionally, the $150 million catastrophe bond arrangement provides coverage of approximately 60% of Florida homeowners-related hurricane losses between $750 million and $1.0 billion.

Our primary property catastrophe treaty for events outside the United States, including Canada, provides coverage of approximately 75% of losses (net of recoveries from other available reinsurance) between $100 million and $350 million. For catastrophic events in Australia and Canada, additional reinsurance provides coverage of 80% of losses between $350 million and $475 million.

In addition to catastrophe treaties, we also have a commercial property per risk treaty. This treaty provides coverage per risk of approximately $625 million to $850 million (depending upon the currency in which the insurance policy was issued) in excess of our initial retention. Our initial retention is generally between $25 million and $35 million.

In addition to our major property catastrophe and property per risk treaties, we purchase several smaller property treaties that only cover specific classes of business or locations having potential concentrations of risk.

Recoveries under our property reinsurance treaties are subject to certain coinsurance requirements that affect the interaction of some elements of our reinsurance program.

Our property reinsurance treaties generally contain terrorism exclusions for acts perpetrated by foreign terrorists, and for nuclear, biological, chemical and radiological loss causes whether such acts are perpetrated by foreign or domestic terrorists.

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After decreasing somewhat in 2010, reinsurance rates for property risks stabilized in 2011. Consequently, the overall cost of our property reinsurance program was similar in 2011 and 2010. We do not expect the changes we made to our reinsurance program during 2011 to have a material effect on the Corporation's results of operations, financial condition or liquidity.

Our major, traditional property reinsurance treaties expire on April 1, 2012 and we are in the process of evaluating our 2012 property reinsurance program. Due to the significant worldwide catastrophe losses incurred by the industry in 2011, we expect that reinsurance rates for property risks will increase somewhat in 2012. The final structure of our reinsurance program and amount of coverage purchased, including the mixture of traditional catastrophe reinsurance and collateralized reinsurance coverage funded through the issuance of collateralized risk linked securities, is still being determined and will affect our total reinsurance costs in 2012.

Profitability

The combined loss and expense ratio (or combined ratio), expressed as a percentage, is the key measure of underwriting profitability traditionally used in the property and casualty insurance business. Management evaluates the performance of our underwriting operations and of each of our business units using, among other measures, the combined loss and expense ratio calculated in accordance with statutory accounting principles. It is the sum of the ratio of losses and loss expenses to premiums earned (loss ratio) plus the ratio of statutory underwriting expenses to premiums written (expense ratio) after reducing both premium amounts by dividends to policyholders. When the combined ratio is under 100%, underwriting results are generally considered profitable; when the combined ratio is over 100%, underwriting results are generally considered unprofitable.

Statutory accounting principles applicable to property and casualty insurance companies differ in certain respects from generally accepted accounting principles (GAAP). Under statutory accounting principles, policy acquisition and other underwriting expenses are recognized immediately, not at the time premiums are earned. Management uses underwriting results determined in accordance with GAAP, among other measures, to assess the overall performance of our underwriting operations. To convert statutory underwriting results to a GAAP basis, policy acquisition expenses are deferred and amortized over the period in which the related premiums are earned. Underwriting income determined in accordance with GAAP is defined as premiums earned less losses and loss expenses incurred and GAAP underwriting expenses incurred.

An accident year is the calendar year in which a loss is incurred or, in the case of claims-made policies, the calendar year in which a loss is reported. The total losses and loss expenses incurred for a particular calendar year include current accident year losses and loss expenses as well as any increases or decreases to our estimates of losses and loss expenses that occurred in all prior accident years, which we refer to as prior year loss development.

Underwriting results were profitable in 2011 and highly profitable in both 2010 and 2009. The combined loss and expense ratio for our overall property and casualty business was as follows:

Years Ended December 31
2011 2010 2009

Loss ratio

63.8 % 58.1 % 55.4 %

Expense ratio

31.5 31.2 30.6

Combined loss and expense ratio

95.3 % 89.3 % 86.0 %

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The loss ratio was higher in 2011 compared to 2010 due to a higher impact of catastrophes and a modest increase in the current accident year loss ratio excluding catastrophes. The loss ratio was higher in 2010 compared to 2009 also due primarily to a higher impact of catastrophes, but offset in part by a modest decrease in the current accident year loss ratio excluding catastrophes. In each of the last three years, the loss ratio reflected positive loss experience excluding catastrophes that we believe resulted from our disciplined underwriting in recent years. Results in all three years benefited to a similar extent from favorable prior year loss development. For more information on prior year loss development, see "Property and Casualty Insurance - Loss Reserves, Prior Year Loss Development ."

In 2011, the impact of catastrophes was $1.0 billion, which represented 8.9 percentage points of the combined ratio. The impact of catastrophes was $634 million in 2010 and $91 million in 2009, which represented 5.7 percentage points and 0.8 percentage points, respectively, of the combined ratio. A significant portion of the catastrophe losses in 2011 related to flooding in Australia as well as tornadoes and other storms in the United States, including losses of about $300 million related to Hurricane Irene. A significant portion of the catastrophe losses in 2010 related to numerous storms in the United States and, to a lesser extent, an earthquake in Chile.

We did not have any recoveries from our primary catastrophe reinsurance treaties during the three year period ended December 31, 2011 because there was no individual catastrophe for which our losses exceeded our retention under the treaties. Under a region-specific property catastrophe reinsurance treaty, we made recoveries of about $60 million of our gross losses related to the 2010 earthquake in Chile.

Our expense ratio was higher in 2011 compared with 2010, which in turn was higher compared with 2009. The increase in 2011 was due primarily to an increase in commission rates on business written outside the United States partially offset by overhead expenses increasing at a lower rate than the rate of growth of premiums written. The increase in 2010 was due to an increase in commissions and, to a lesser extent, overhead expenses increasing at a rate that exceeded the rate of growth of premiums written. In both 2011 and 2010, our overall commission rate increased due primarily to premium growth outside the United States in classes of business with higher commission rates.

Review of Underwriting Results by Business Unit

Personal Insurance

Net premiums written from personal insurance, which represented 34% of our premiums written in 2011, increased by 4% in 2011 and 5% in 2010 compared with the respective prior year. Net premiums written for the classes of business within the personal insurance segment were as follows:

Years Ended December 31
% Increase
% Increase
2011 2011 vs. 2010 2010 2010 vs. 2009 2009
(dollars in millions)

Automobile

$ 682 7 % $ 638 11 % $ 577

Homeowners

2,477 4 2,382 2 2,339

Other

818 2 805 9 741

Total personal

$ 3,977 4 $ 3,825 5 $ 3,657

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Personal automobile premiums increased in 2011 and 2010, reflecting new business growth in select non-U.S. locations and the positive impact of currency fluctuation on business written outside the United States. Personal automobile premiums in the United States increased slightly in 2011 and decreased slightly in 2010 as growth continued to be constrained by the highly competitive marketplace. Premiums for our homeowners business increased modestly in 2011 and increased slightly in 2010. Premium growth in this business has been constrained due to the downturn in the U.S. economy in recent years, which resulted in a slowdown in new housing construction as well as lower demand for jewelry and fine arts policy endorsements. In 2011, however, growth was achieved both inside and outside the United States, due primarily to new business and, to a lesser extent, increases in coverage on some existing policies. Premiums from our other personal business, which includes accident and health, excess liability and yacht coverages, increased slightly in 2011 due to moderate growth in the excess liability business. In accident and health, significant growth in our non-U.S. business in 2011, attributable to new business initiatives and, to a lesser extent, to the positive effect of currency fluctuation, was offset by a significant decrease in premiums in the United States, due to our decision to exit and run off the employer health care stop loss component of this business. The growth in other personal premiums in 2010 was primarily in our non-U.S. accident and health business and approximately half was attributable to the effect of currency fluctuation.

Our personal insurance business produced modestly profitable underwriting results in 2011. Results were highly profitable in 2010 and 2009, but less so in 2010. Results were less profitable in each successive year due in large part to a higher impact of catastrophe losses on our homeowners business. The impact of catastrophes accounted for 13.1 percentage points of the combined loss and expense ratio for our personal business in 2011, compared with 10.2 percentage points in 2010 and 0.9 percentage points in 2009. A significant portion of the catastrophe losses in 2011 related to storms in the United States, including Hurricane Irene. A significant portion of the catastrophe losses in 2010 related to numerous storms in the United States. The less profitable results in 2011 compared to 2010 were also attributable to a higher expense ratio, a higher current accident year loss ratio excluding catastrophes and a lower amount of favorable prior year loss development. The combined loss and expense ratios for the classes of business within the personal insurance segment were as follows:

Years Ended December 31
2011 2010 2009

Automobile

94.4 % 90.8 % 90.4 %

Homeowners

100.2 91.7 80.4

Other

95.7 91.2 90.8

Total personal

98.3 91.5 84.1

Our personal automobile results were profitable in 2011 and highly profitable in 2010 and 2009. Results in all three years benefited from moderate claim frequency and favorable prior year loss development.

Homeowners results were breakeven in 2011 and highly profitable in 2010 and 2009. Results in each succeeding year were less profitable than the respective prior year due primarily to higher catastrophe losses. The impact of catastrophes accounted for 20.6 percentage points of the combined loss and expense ratio for this class in 2011 compared with 15.6 percentage points in 2010 and 1.5 percentage points in 2009. Results in 2011 were also adversely impacted by more severe non-catastrophe weather-related losses than in 2010.

Other personal business produced profitable results in each of the past three years, but less so in 2011. The less profitable results in 2011 compared to 2010 were primarily due to reduced profitability in the accident and health and excess liability components. Results for our excess liability business, however, were highly profitable in all three years and benefited from favorable prior year loss development as a result of better than expected loss trends. Our yacht business was also highly profitable in each of the past three years. Our accident and health business produced breakeven results in 2011 and 2009 compared with profitable results in 2010.

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Commercial Insurance

Net premiums written from commercial insurance, which represented 43% of our premiums written in 2011, increased by 8% in 2011 and were flat in 2010 compared with the respective prior year. Net premiums written for the classes of business within the commercial insurance segment were as follows:

Years Ended December 31
% Increase
% Increase
(Decrease)
2011 2011 vs. 2010 2010 2010 vs. 2009 2009
(dollars in millions)

Multiple peril

$ 1,136 4 % $ 1,094 (2 )% $ 1,121

Casualty

1,639 7 1,532 1 1,514

Workers' compensation

860 14 756 (1 ) 761

Property and marine

1,416 9 1,294 2 1,264

Total commercial

$ 5,051 8 $ 4,676 - $ 4,660

In 2011, premium growth occurred in all classes of our commercial insurance business. This premium growth reflected higher rates, new business opportunities and slightly higher amounts of audit and endorsement premiums in a market that continued to be highly competitive. In 2011, there was improvement in the overall rate environment, particularly in the United States, throughout the year. Average renewal rates in the United States increased over those in 2010 for all major classes of our commercial business. In 2011, the average renewal exposure change was flat in the United States and up slightly outside the United States, an improvement from 2010. Growth in our commercial classes in 2010 was limited by a very competitive marketplace and the restrained insurance purchasing demand of customers operating in weakened economies worldwide. Net premiums written in 2010 reflected slightly reduced exposures on renewal business in the United States due to the continuing effects of the weak economy, although the effect on renewal exposures progressively lessened throughout the year. On average, renewal rates in the United States for most classes of commercial insurance business were about flat in 2010 compared with 2009. Premium growth in both 2011 and 2010 in our commercial insurance business benefited slightly from the impact of currency fluctuation on business written outside the United States.

Retention levels of our existing policyholders remained strong over the last three years. New business volume was up modestly in 2011 compared with 2010, driven by activity outside the United States. New business volume was up modestly in 2010 compared with 2009.

We continued to maintain our underwriting discipline in the highly competitive market, renewing business and writing new business only where we believe we are securing acceptable rates and appropriate terms and conditions for the exposures.

Our commercial insurance business produced near breakeven underwriting results in 2011 compared to profitable results in 2010 and highly profitable results in 2009. Results in all three years benefited from favorable loss experience, disciplined risk selection and appropriate terms and conditions in recent years. Results were less profitable in each successive year mainly due to a higher impact of catastrophes. The impact of catastrophes accounted for 10.5 percentage points of the combined loss and expense ratio for our commercial insurance business in 2011, compared with 5.4 percentage points in 2010 and 1.2 percentage points in 2009. The less profitable results in 2011 compared with 2010 were also due to a higher current accident year loss ratio excluding catastrophes. Excluding the effect of catastrophes, our commercial insurance results were slightly more profitable in 2010 compared to 2009, due to a higher amount of favorable prior year loss development in 2010.

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The combined loss and expense ratios for the classes of business within commercial insurance were as follows:

Years Ended December 31
2011 2010 2009

Multiple peril

101.5 % 94.7 % 85.8 %

Casualty

87.9 91.7 96.7

Workers' compensation

93.2 93.4 92.7

Property and marine

114.7 90.5 83.3

Total commercial

99.3 92.3 89.9

Multiple peril results were slightly unprofitable in 2011 compared with profitable results in 2010 and highly profitable results in 2009. The less profitable results in 2011 compared with 2010 were mainly due to a higher impact of catastrophes in the property component of this business, offset in part by more profitable results in the liability component due to a higher amount of favorable prior year loss development. The less profitable results in 2010 compared with 2009 were due primarily to a higher impact of catastrophes in the property component and, to a lesser extent, less profitable results in the liability component. The impact of catastrophes accounted for 15.1 percentage points of the combined loss and expense ratio for the multiple peril class in 2011 compared with 10.3 percentage points in 2010 and 1.6 percentage points in 2009. The property component reflected moderate non-catastrophe losses in all three years, particularly outside the United States in 2010.

Results for our casualty business were profitable in each of the past three years, increasingly so in 2011 and 2010 compared to the respective prior year. The automobile and primary liability components of our casualty business were profitable in each of the past three years, but more so in 2011 due to a higher amount of favorable prior year loss development. Results in the excess liability component were increasingly profitable in each of the past three years. Excess liability results in all three years benefited from favorable prior year loss development mainly due to lower than expected claim severity. Casualty results in each of the three years were adversely affected by incurred losses related to toxic waste claims and, to a lesser extent in 2011, asbestos claims. Our analysis of these exposures resulted in increases in the estimate of our ultimate liabilities. Such losses represented 4.0 percentage points of the combined loss and expense ratio for this class in 2011, 3.5 percentage points in 2010 and 4.1 percentage points in 2009.

Workers' compensation results were profitable in each of the past three years reflecting our disciplined risk selection during the past several years. Results in 2011 benefited from modest favorable prior year loss development.

Property and marine results were highly unprofitable in 2011 compared with profitable results in 2010 and highly profitable results in 2009. The deterioration in results in each succeeding year was primarily due to higher catastrophe losses. Catastrophe losses accounted for 24.9 percentage points of the combined loss and expense ratio in 2011 compared with 8.9 percentage points in 2010 and 1.5 percentage points in 2009. Excluding the impact of catastrophes, the combined ratio was 89.8%, 81.6% and 81.8% in 2011, 2010 and 2009, respectively. On this basis, the worse result in 2011 compared to 2010 and 2009 primarily reflected a higher non-catastrophe loss ratio, including a higher frequency of large losses, in the current accident year.

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Specialty Insurance

Net premiums written from specialty insurance, which represented 23% of our premiums written in 2011, were flat in 2011 and 2010 compared with the respective prior year. Net premiums written for the classes of business within the specialty insurance segment were as follows:

Years Ended December 31
% Increase
% Increase
(Decrease)
2011 2011 vs. 2010 2010 2010 vs. 2009 2009
(dollars in millions)

Professional liability

$ 2,388 - % $ 2,398 (1 )% $ 2,413

Surety

332 1 329 1 326

Total specialty

$ 2,720 - $ 2,727 - $ 2,739

Net premiums written in our professional liability business were relatively flat in 2011 and 2010 compared with the respective prior year. Premium growth for this business has been constrained by the continuing effect of the economic downturn in recent years and a highly competitive marketplace due to an oversupply of capacity available from market participants. We experienced a slight overall decrease in our average renewal rates and new business volume but relatively strong retention of our expiring policies in 2011 and 2010 compared with the respective prior year. Premium growth in our professional liability business in 2011 and 2010 benefited slightly from the impact of currency fluctuation on business written outside the United States.

Overall, the average renewal rates of our professional liability business written in the United States decreased in both 2011 and 2010, but less so in 2011. Rates were down in most lines of our professional liability business in 2010, with the most significant reduction in rates in our directors and officers liability business. However, in 2011, renewal rate reductions moderated throughout the year for most lines of professional liability business.

Retention levels in the professional liability classes remained strong over the last three years. New business volume declined slightly in each of the past two years, due in varying degrees to the competition in the marketplace as well as the effects of the economic downturn. We maintained our focus on small and middle market publicly traded and privately held companies and our commitment to maintaining underwriting discipline in this environment. We continued to obtain what we believe are acceptable rates and appropriate terms and conditions on both new and renewal business.

Premium growth in our surety business was constrained in 2011 and 2010 by the highly competitive environment and the lingering effects of the weak economic conditions on the construction business during the last few years. The slight growth in both 2011 and 2010 was attributable to new business in non-U.S. locations.

Our specialty insurance business produced highly profitable underwriting results in each of the last three years. The combined loss and expense ratios for the classes of business within specialty insurance were as follows:

Years Ended December 31
2011 2010 2009

Professional liability

89.9 % 87.8 % 90.1 %

Surety

49.1 41.3 37.4

Total specialty

85.1 82.2 84.1

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Our professional liability business produced highly profitable results in each of the past three years. The profitability of our professional liability business was particularly strong outside the United States in all three years, especially in 2010. The fiduciary liability class produced highly profitable results in each of the three past years. The directors and officers liability class was profitable in all three years, particularly in 2011 and 2010. The fidelity class was profitable in each of the past three years, but less so in each successive year, primarily due to increased large loss activity resulting from alleged third party and insured-employee criminal activity in recent years. The employment practices liability class was near breakeven in 2011 compared with highly profitable results in 2010 and 2009. The less profitable results in 2011 in this class were due to deterioration in the current accident year loss ratio, while results in 2010 and 2009 benefited from favorable prior year loss development. Our errors and omissions liability business produced highly unprofitable results in each of the past three years partly reflecting the impact of the financial crisis and unfavorable prior year loss development.

Collectively, the results for the professional liability classes benefited from favorable prior year loss development in the past three years that was driven mainly by positive loss experience related to accident years 2008 and prior. The combined ratio for the current accident year in our professional liability business in 2011 and 2010 was near breakeven, while the combined ratio for the current accident year in 2009 was higher since that accident year was more affected by the crisis in the financial markets.

Our surety business produced highly profitable results in each of the past three years due to favorable loss experience. Our surety business tends to be characterized by losses that are infrequent but have the potential to be highly severe. When losses occur, they are mitigated, at times, by recovery rights to the customer's assets, contract payments, collateral and bankruptcy recoveries.

The majority of our surety obligations are intended to be performance-based guarantees. We manage our exposure by individual account and by specific bond type. We have substantial commercial and construction surety exposure for current and prior customers, including exposures related to surety bonds issued on behalf of companies that have experienced deterioration in creditworthiness since we issued bonds to them. We therefore may experience an increase in filed claims and may incur high severity losses, especially in light of ongoing economic conditions. Such losses would be recognized if and when claims are filed and determined to be valid, and could have a material adverse effect on the Corporation's results of operations.

Reinsurance Assumed

In 2005, we transferred our ongoing reinsurance assumed business and certain related assets, including renewal rights, to a reinsurance company. The reinsurer generally did not assume our reinsurance liabilities relating to reinsurance contracts incepting prior to December 31, 2005. We retained those liabilities and the related assets.

For a transition period of about two years, the same reinsurer underwrote specific reinsurance business on our behalf. We retained a portion of this business and ceded the balance to the reinsurer.

Net premiums written from our reinsurance assumed business during the past three years have not been significant as this business is in runoff.

Reinsurance assumed results were profitable in each of the past three years. Prior year loss development was favorable in all three years, but more so in 2009.

Catastrophe Risk Management

Our property and casualty subsidiaries have exposure to losses caused by natural perils such as hurricanes and other windstorms, earthquakes, severe winter weather and brush fires as well as from man-made catastrophic events such as terrorism. The frequency and severity of catastrophes are inherently unpredictable.

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Natural Catastrophes

The extent of losses from a natural catastrophe is a function of both the total amount of insured exposure in an area affected by the event and the severity of the event. We regularly assess our concentration of risk exposures in natural catastrophe exposed areas globally and have strategies and underwriting standards to manage this exposure through individual risk selection, subject to regulatory constraints, and through the purchase of catastrophe reinsurance coverage. We use catastrophe modeling and a risk concentration management tool to monitor and control our accumulations of potential losses in natural catastrophe exposed areas in the United States, such as California and the gulf and east coasts, as well as in natural catastrophe exposed areas in other countries. The information provided by the catastrophe modeling and the risk concentration management tool has resulted in our non-renewing some accounts and refraining from writing others.

A new version of one of the third party catastrophe modeling tools that we and others in the insurance industry utilize for estimating potential losses from natural catastrophes was released during the first quarter of 2011. Overall, the model indicates higher risk estimates for our exposure to hurricanes in the United States, but the impact of the new model on our book of business varies significantly among the regions that we model for hurricanes. Based on our analysis, and the indications of other catastrophe models, we are implementing targeted underwriting and rate initiatives in some regions and we purchased additional catastrophe reinsurance. We will continue to take underwriting actions and/or purchase additional reinsurance to reduce or mitigate our exposure as we believe is warranted.

Catastrophe modeling generally relies on multiple inputs based on experience, science, engineering and history, and the selection of those inputs requires a significant amount of judgment. The modeling results may also fail to account for risks that are outside the range of normal probability or are otherwise unforeseen. Because of this, actual results may differ materially from those derived from our modeling exercises.

We also continue to actively explore and analyze credible scientific evidence, including the potential impact of global climate change, that may affect our ability to manage exposure under the insurance policies we issue as well as the impact that laws and regulations intended to combat climate change may have on us.

Despite our efforts to manage our catastrophe exposure, the occurrence of one or more severe natural catastrophic events in heavily populated areas could have a material effect on the Corporation's results of operations, financial condition or liquidity.

Terrorism Risk and Legislation

The September 11, 2001 attack changed the way the property and casualty insurance industry views catastrophic risk. That tragic event demonstrated that numerous classes of business we write are subject to terrorism related catastrophic risks in addition to the catastrophic risks related to natural occurrences. This, together with the limited availability of terrorism reinsurance, required us to change how we identify and evaluate risk accumulations. We have licensed a terrorism model that provides loss estimates under numerous event scenarios. Actual results may differ materially from those suggested by the model. The risk concentration management tool referred to above also enables us to identify locations and geographic areas that are exposed to risk accumulations. The information provided by the terrorism model and the risk concentration management tool has resulted in our non-renewing some accounts, subject to regulatory constraints, and refraining from writing others.

The Terrorism Risk Insurance Act of 2002 and more recently, the Terrorism Risk Insurance Program Reauthorization Act of 2007 (collectively TRIA), are limited duration programs under which the U.S. federal government has agreed to share the risk of loss arising from certain acts of terrorism with the insurance industry. The current program, which will terminate on December 31, 2014, is applicable to many lines of commercial business but excludes, among others, commercial automobile, surety and

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professional liability insurance, other than directors and officers liability. The current program provides protection from all foreign and domestic acts of terrorism.

As a precondition to recovery under TRIA, insurance companies with direct commercial insurance exposure in the United States for TRIA lines of business are required to make insurance for covered acts of terrorism available under their policies. In the event of an act of terrorism, each insurer has a separate deductible that it must meet before federal assistance becomes available. The deductible is based on a percentage of direct U.S. earned premiums for the covered lines of business in the previous calendar year. For 2012, that deductible is 20% of direct premiums earned in 2011 for these lines of business. For losses above the deductible, the federal government will pay for 85% of covered losses, while the insurer retains 15%. There is a combined annual aggregate limit for the federal government and all insurers of $100 billion. If acts of terrorism result in covered losses exceeding the $100 billion annual limit, insurers are not liable for additional losses. While the provisions of TRIA will serve to mitigate our exposure in the event of a large-scale terrorist attack, our deductible is substantial, approximating $930 million in 2012.

For certain classes of business, such as workers' compensation, terrorism coverage is mandatory. For those classes of business where it is not mandatory, policyholders may choose not to purchase terrorism coverage, which would, subject to other statutory or regulatory restrictions, reduce our exposure.

We also have exposure outside the United States to risk of loss from acts of terrorism. In some jurisdictions, we have access to government mechanisms that would mitigate our exposure.

We will continue to manage this type of catastrophic risk by monitoring terrorism risk aggregations. Nevertheless, given the unpredictability of the targets, frequency and severity of potential terrorist events as well as the very limited terrorism reinsurance coverage available in the market and the limitations of existing government programs and uncertainty regarding their availability in the future, the occurrence of a terrorist event could have a material adverse effect on the Corporation's results of operations, financial condition or liquidity.

Loss Reserves

Unpaid losses and loss expenses, also referred to as loss reserves, are the largest liability of our property and casualty subsidiaries.

Our loss reserves include case estimates for claims that have been reported and estimates for claims that have been incurred but not reported at the balance sheet date as well as estimates of the expenses associated with processing and settling all reported and unreported claims, less estimates of anticipated salvage and subrogation recoveries. Estimates are based upon past loss experience modified for current trends as well as prevailing economic, legal and social conditions. Our loss reserves are not discounted to present value.

We regularly review our loss reserves using a variety of actuarial techniques. We update the reserve estimates as historical loss experience develops, additional claims are reported and/or settled and new information becomes available. Any changes in estimates are reflected in operating results in the period in which the estimates are changed.

Incurred but not reported (IBNR) reserve estimates are generally calculated by first projecting the ultimate cost of all claims that have occurred and then subtracting reported losses and loss expenses. Reported losses include cumulative paid losses and loss expenses plus case reserves. The IBNR reserve includes a provision for claims that have occurred but have not yet been reported to us, some of which are not yet known to the insured, as well as a provision for future development on reported claims. A relatively large proportion of our net loss reserves, particularly for long tail liability classes, are reserves for IBNR losses. In fact, about 70% of our aggregate net loss reserves at December 31, 2011 were for IBNR losses.

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Our gross case and IBNR loss reserves and related reinsurance recoverable by class of business were as follows:

Net
Gross Loss Reserves Reinsurance
Loss
December 31, 2011 Case IBNR Total Recoverable Reserves
(in millions)

Personal insurance

Automobile

$ 269 $ 151 $ 420 $ 16 $ 404

Homeowners

431 349 780 11 769

Other

392 649 1,041 139 902

Total personal

1,092 1,149 2,241 166 2,075

Commercial insurance

Multiple peril

600 1,169 1,769 34 1,735

Casualty

1,388 5,229 6,617 343 6,274

Workers' compensation

913 1,669 2,582 190 2,392

Property and marine

896 558 1,454 336 1,118

Total commercial

3,797 8,625 12,422 903 11,519

Specialty insurance

Professional liability

1,498 6,098 7,596 416 7,180

Surety

27 54 81 6 75

Total specialty

1,525 6,152 7,677 422 7,255

Total insurance

6,414 15,926 22,340 1,491 20,849

Reinsurance assumed

240 488 728 248 480

Total

$ 6,654 $ 16,414 $ 23,068 $ 1,739 $ 21,329

Net
Gross Loss Reserves Reinsurance
Loss
December 31, 2010 Case IBNR Total Recoverable Reserves
(in millions)

Personal insurance

Automobile

$ 257 $ 155 $ 412 $ 17 $ 395

Homeowners

383 327 710 18 692

Other

359 663 1,022 145 877

Total personal

999 1,145 2,144 180 1,964

Commercial insurance

Multiple peril

607 1,136 1,743 38 1,705

Casualty

1,446 5,058 6,504 363 6,141

Workers' compensation

897 1,512 2,409 175 2,234

Property and marine

664 487 1,151 332 819

Total commercial

3,614 8,193 11,807 908 10,899

Specialty insurance

Professional liability

1,477 6,329 7,806 418 7,388

Surety

16 50 66 8 58

Total specialty

1,493 6,379 7,872 426 7,446

Total insurance

6,106 15,717 21,823 1,514 20,309

Reinsurance assumed

261 634 895 303 592

Total

$ 6,367 $ 16,351 $ 22,718 $ 1,817 $ 20,901

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Loss reserves, net of reinsurance recoverable, increased by $428 million or 2% in 2011. The effect of catastrophes increased loss reserves by $285 million and the effect of foreign currency fluctuation increased reserves by $67 million, due to a weaker U.S. dollar at December 31, 2011 compared to December 31, 2010. Loss reserves related to our insurance business increased by $540 million. Loss reserves related to our reinsurance assumed business, which is in runoff, decreased by $112 million.

Total gross case reserves related to our insurance business increased by $308 million in 2011. A majority of this increase was in the homeowners and property and marine classes due to catastrophe losses reported during the year that remained unpaid as of December 31, 2011. Total gross IBNR reserves related to our insurance business increased by $209 million in 2011. An increase in gross IBNR reserves in the commercial classes, primarily in the casualty and workers' compensation classes due to increased exposures and in the property-related classes due to higher catastrophe-related reserves, was offset in part by a decrease in gross IBNR reserves in the professional liability classes, reflecting increased case activity and favorable prior year development.

In establishing the loss reserves of our property and casualty subsidiaries, we consider facts currently known and the present state of the law and coverage litigation. Based on all information currently available, we believe that the aggregate loss reserves at December 31, 2011 were adequate to cover claims for losses that had occurred as of that date, including both those known to us and those yet to be reported. However, as described below, there are significant uncertainties inherent in the loss reserving process. It is therefore possible that management's estimate of the ultimate liability for losses that had occurred as of December 31, 2011 may change, which could have a material effect on the Corporation's results of operations and financial condition.

Estimates and Uncertainties

The process of establishing loss reserves is complex and imprecise as it must take into consideration many variables that are subject to the outcome of future events. As a result, informed subjective estimates and judgments as to our ultimate exposure to losses are an integral component of our loss reserving process.

Given the inherent complexity of the loss reserving process and the potential variability of the assumptions used, the actual emergence of losses could vary, perhaps substantially, from the estimate of losses included in our financial statements, particularly in those instances where settlements do not occur until well into the future. Our net loss reserves at December 31, 2011 were $21.3 billion. Therefore, a relatively small percentage change in the estimate of net loss reserves would have a material effect on the Corporation's results of operations.

Reserves Other than Those Relating to Asbestos and Toxic Waste Claims.   Our loss reserves include amounts related to short tail and long tail classes of business. "Tail" refers to the time period between the occurrence of a loss and the settlement of the claim. The longer the time span between the incidence of a loss and the settlement of the claim, the more the ultimate settlement amount can vary.

Short tail classes consist principally of homeowners, commercial property and marine business. For these classes, claims are generally reported and settled shortly after the loss occurs and the claims usually relate to tangible property. Consequently, the estimation of loss reserves for these classes is less complex.

Most of our loss reserves relate to long tail liability classes of business. Long tail classes include directors and officers liability, errors and omissions liability and other professional liability coverages, commercial primary and excess liability, workers' compensation and other liability coverages. For many liability claims significant periods of time, ranging up to several years or more, may elapse between the occurrence of the loss, the reporting of the loss to us and the settlement of the claim. As a result, loss experience in the more recent accident years for the long tail liability classes has limited statistical credibility because a relatively small proportion of losses in these accident years are reported claims and an even smaller proportion are paid losses.

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An accident year is the calendar year in which a loss is incurred or, in the case of claims-made policies, the calendar year in which a loss is reported. Liability claims are also more susceptible to litigation and can be significantly affected by changing contract interpretations and the legal and economic environment. Consequently, the estimation of loss reserves for these classes is more complex and typically subject to a higher degree of variability than for short tail classes. As a result, the role of judgment is much greater for these reserve estimates.

Most of our reinsurance assumed business is long tail casualty reinsurance. Reserve estimates for this business are therefore subject to the variability caused by extended loss emergence periods. The estimation of loss reserves for this business is further complicated by delays between the time the claim is reported to the ceding insurer and when it is reported by the ceding insurer to us and by our dependence on the quality and consistency of the loss reporting by the ceding company.

Our actuaries perform a comprehensive review of loss reserves for each of the numerous classes of business we write at least once a year. The timing of such review varies by class of business and, for some classes, the jurisdiction in which the policy was written. The review process takes into consideration the variety of trends that impact the ultimate settlement of claims in each particular class of business. Additionally, each quarter our actuaries review the emergence of paid and reported losses relative to expectations and, as necessary, conduct reserve reviews for particular classes of business.

The loss reserve estimation process relies on the basic assumption that past experience, adjusted for the effects of current developments and likely trends, is an appropriate basis for predicting future outcomes. As part of that process, our actuaries use a variety of actuarial methods that analyze experience, trends and other relevant factors. The principal standard actuarial methods used by our actuaries in the loss reserve reviews include loss development factor methods, expected loss ratio methods, Bornheutter-Ferguson methods and frequency/severity methods.

Loss development factor methods generally assume that the losses yet to emerge for an accident year are proportional to the paid or reported loss amounts observed so far. Historical patterns of the development of paid and reported losses by accident year can be predictive of the expected future patterns that are applied to current paid and reported losses to generate estimated ultimate losses by accident year.

Expected loss ratio methods use loss ratios for prior accident years, adjusted to reflect our evaluation of recent loss trends, the current risk environment, changes in our book of business and changes in our pricing and underwriting, to determine the appropriate expected loss ratio for a given accident year. The expected loss ratio for each accident year is multiplied by the earned premiums for that year to calculate estimated ultimate losses.

Bornheutter-Ferguson methods are combinations of an expected loss ratio method and a loss development factor method, where the loss development factor method is given more weight as an accident year matures.

Frequency/severity methods first project ultimate claim counts (using one or more of the other methods described above) and then multiply those counts by an estimated average claim cost to calculate estimated ultimate losses. The average claim costs are often estimated through a regression analysis of historical severity data. Generally, these methods work best for high frequency, low severity classes of business.

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In completing their loss reserve analysis, our actuaries are required to determine the most appropriate actuarial methods to employ for each class of business. Within each class, the business is further segregated by accident year and, where appropriate, by jurisdiction. Each estimation method has its own pattern, parameter and/or judgmental dependencies, with no estimation method being better than the others in all situations. The relative strengths and weaknesses of the various estimation methods when applied to a particular class of business can also change over time, depending on the underlying circumstances. In many cases, multiple estimation methods will be valid for the particular facts and circumstances of the relevant class of business. The manner of application and the degree of reliance on a given method will vary by class of business, by accident year and by jurisdiction based on our actuaries' evaluation of the above dependencies and the potential volatility of the loss frequency and severity patterns. The estimation methods selected or given weight by our actuaries at a particular valuation date are those that are believed to produce the most reliable indication for the loss reserves being evaluated. These selections incorporate input from claims personnel, pricing actuaries and underwriting management on loss cost trends and other factors that could affect the reserve estimates.

For short tail classes, the emergence of paid and incurred losses generally exhibits a reasonably stable pattern of loss development from one accident year to the next. Thus, for these classes, the loss development factor method is generally relatively straightforward to apply and usually requires only modest extrapolation. For long tail classes, applying the loss development factor method often requires more judgment in selecting development factors as well as more significant extrapolation. For those long tail classes with high frequency and relatively low per-loss severity (e.g., workers' compensation), volatility will often be sufficiently modest for the loss development factor method to be given significant weight, except in the most recent accident years.

For certain long tail classes of business, however, anticipated loss experience is less predictable because of the small number of claims and erratic claim severity patterns. These classes include directors and officers liability, errors and omissions liability and commercial excess liability, among others. For these classes, the loss development factor methods may not produce a reliable estimate of ultimate losses in the most recent accident years since many claims either have not yet been reported to us or are only in the early stages of the settlement process. Therefore, the actuarial estimates for these accident years are based on less extrapolatory methods, such as expected loss ratio and Bornheutter-Ferguson methods. Over time, as a greater number of claims are reported and the statistical credibility of loss experience increases, loss development factor methods are given increasingly more weight.

Using all the available data, our actuaries select an indicated loss reserve amount for each class of business based on the various assumptions, projections and methods. The total indicated reserve amount determined by our actuaries is an aggregate of the indicated reserve amounts for the individual classes of business. The ultimate outcome is likely to fall within a range of potential outcomes around this indicated amount, but the indicated amount is not expected to be precisely the ultimate liability.

Senior management meets with our actuaries at the end of each quarter to review the results of the latest loss reserve analysis. Based on this review, management determines the carried reserve for each class of business. In making the determination, management considers numerous factors, such as changes in actuarial indications in the period, the maturity of the accident year, trends observed over the recent past and the level of volatility within a particular class of business. In doing so, management must evaluate whether a change in the data represents credible actionable information or an anomaly. Such an assessment requires considerable judgment. Even if a change is determined to be permanent, it is not always possible to determine the extent of the change until sometime later. As a result, there can be a time lag between the emergence of a change and a determination that the change should be reflected in the carried loss reserves. In general, changes are made more quickly to more mature accident years and less volatile classes of business.

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Among the numerous factors that contribute to the inherent uncertainty in the process of establishing loss reserves are the following:

•  changes in the inflation rate for goods and services related to covered damages such as medical care and home repair costs,
•  changes in the judicial interpretation of policy provisions relating to the determination of coverage,
•  changes in the general attitude of juries in the determination of liability and damages,
•  legislative actions,
•  changes in the medical condition of claimants,
•  changes in our estimates of the number and/or severity of claims that have been incurred but not reported as of the date of the financial statements,
•  changes in our book of business,
•  changes in our underwriting standards, and
•  changes in our claim handling procedures.

In addition, we must consider the uncertain effects of emerging or potential claims and coverage issues that arise as legal, judicial and social conditions change. These issues have had, and may continue to have, a negative effect on our loss reserves by either extending coverage beyond the original underwriting intent or by increasing the number or size of claims. Examples of such issues include professional liability claims arising out of the recent crisis in the financial markets, directors and officers liability and errors and omissions liability claims arising out of accounting and other corporate malfeasance, and exposure to claims asserted for bodily injury as a result of long term exposure to harmful products or substances. As a result of issues such as these, the uncertainties inherent in estimating ultimate claim costs on the basis of past experience have grown, further complicating the already complex loss reserving process.

As part of our loss reserving analysis, we take into consideration the various factors that contribute to the uncertainty in the loss reserving process. Those factors that could materially affect our loss reserve estimates include loss development patterns and loss cost trends, rate and exposure level changes, the effects of changes in coverage and policy limits, business mix shifts, the effects of regulatory and legislative developments, the effects of changes in judicial interpretations, the effects of emerging claims and coverage issues and the effects of changes in claim handling practices. In making estimates of reserves, however, we do not necessarily make an explicit assumption for each of these factors. Moreover, all estimation methods do not utilize the same assumptions and typically no single method is determinative in the reserve analysis for a class of business. Consequently, changes in our loss reserve estimates generally are not the result of changes in any one assumption. Instead, the variability will be affected by the interplay of changes in numerous assumptions, many of which are implicit to the approaches used.

For each class of business, we regularly adjust the assumptions and actuarial methods used in the estimation of loss reserves in response to our actual loss experience as well as our judgments regarding changes in trends and/or emerging patterns. In those instances where we primarily utilize analyses of historical patterns of the development of paid and reported losses, this may be reflected, for example, in the selection of revised loss development factors. In those long tail classes of business that comprise a majority of our loss reserves and for which loss experience is less predictable due to potential changes in judicial interpretations, potential legislative actions and potential claims issues, this may be reflected in a judgmental change in our estimate of ultimate losses for particular accident years.

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The future impact of the various factors that contribute to the uncertainty in the loss reserving process is extremely difficult to predict. There is potential for significant variation in the development of loss reserves, particularly for long tail classes of business. We do not derive statistical loss distributions or outcome confidence levels around our loss reserve estimate. Actuarial ranges of reasonable estimates are not a true reflection of the potential volatility between carried loss reserves and the ultimate settlement amount of losses incurred prior to the balance sheet date. This is due, among other reasons, to the fact that actuarial ranges are developed based on known events as of the valuation date whereas the ultimate disposition of losses is subject to the outcome of events and circumstances that were unknown as of the valuation date.

The following discussion includes disclosure of possible variation from current estimates of loss reserves due to a change in certain key assumptions for particular classes of business. These impacts are estimated individually, without consideration for any correlation among such assumptions or among lines of business. Therefore, it would be inappropriate to take the amounts and add them together in an attempt to estimate volatility for our loss reserves in total. We believe that the estimated variation in reserves detailed below is a reasonable estimate of the possible variation that may occur in the future. However, if such variation did occur, it would likely occur over a period of several years and therefore its impact on the Corporation's results of operations would be spread over the same period. It is important to note, however, that there is the potential for future variation greater than the amounts discussed below.

Two of the larger components of our loss reserves relate to the professional liability classes other than fidelity and to commercial excess liability. The respective reported loss development patterns are key assumptions in estimating loss reserves for these classes of business, both as applied directly to more mature accident years and as applied indirectly (e.g., via Bornheutter-Ferguson methods) to less mature accident years.

Reserves for the professional liability classes other than fidelity were $6.8 billion, net of reinsurance, at December 31, 2011. Based on a review of our loss experience, if the loss development factor for each accident year changed such that the cumulative loss development factor for the most recent accident year changed by 10%, we estimate that the net reserves for professional liability classes other than fidelity would change by approximately $700 million, in either direction. This degree of change in the reported loss development pattern is within the historical variation around the averages in our data.

Reserves for commercial excess liability (excluding asbestos and toxic waste claims) were $3.1 billion, net of reinsurance, at December 31, 2011. These reserves are included within commercial casualty. Based on a review of our loss experience, if the loss development factor for each accident year changed such that the cumulative loss development factor for the most recent accident year changed by 20%, we estimate that the net reserves for commercial excess liability would change by approximately $400 million, in either direction. This degree of change in the reported loss development pattern is within the historical variation around the averages in our data.

Reserves Relating to Asbestos and Toxic Waste Claims.