1. General

ACE Limited (ACE or the Company) is a holding company incorporated in Zurich, Switzerland. The Company, through its various subsidiaries, provides a broad range of insurance and reinsurance products to insureds worldwide. ACE operates through the following business segments: Insurance – North American, Insurance – Overseas General, Global Reinsurance, and Life. Refer to Note 9.

The interim unaudited consolidated financial statements, which include the accounts of the Company and its subsidiaries, have been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) and, in the opinion of management, reflect all adjustments (consisting of normally recurring accruals) necessary for a fair statement of the results and financial position for such periods. All significant intercompany accounts and transactions have been eliminated. The results of operations and cash flows for any interim period are not necessarily indicative of the results for the full year. These financial statements should be read in conjunction with the consolidated financial statements, and related notes thereto, included in the Company's Annual Report on Form 10-K for the year ended December 31, 2009.

2. Significant accounting policies

New accounting pronouncements

Adopted in the three months ended March 31, 2010

Consolidation of variable interest entities and accounting for transfers of financial assets

In June 2009, the Financial Accounting Standards Board (FASB) issued Accounting Standard Update (ASU) No. 2009-16, Accounting for Transfers of Financial Assets (ASU 2009-16) and ASU No. 2009-17, Improvements to Financial Reporting by Enterprises Involved With Variable Interest Entities (ASU 2009-17). ASU 2009-16 amends Accounting Standards Codification (ASC) Topic 860, Transfers and Servicing, by removing the exemption from consolidation for qualifying special purpose entities. This statement also limits the circumstances in which a financial asset, or portion of a financial asset, should be derecognized when the transferor has not transferred the entire original financial asset to an entity that is not consolidated with the transferor in the financial statements being presented and/or when the transferor has continuing involvement with the transferred financial asset. ASU 2009-17 amends ASC Topic 810, Consolidation, to eliminate the quantitative approach previously required for determining the primary beneficiary of a variable interest entity and requires ongoing qualitative reassessments of whether an enterprise is the primary beneficiary of a variable interest entity.   ASU 2009-16 and ASU 2009-17 were effective for interim and annual reporting periods beginning on January 1, 2010. The adoption of these provisions did not have a material impact on ACE's financial condition or results of operations.

Fair value measurements and disclosures

In January 2010, the FASB issued ASU No. 2010-06, Improving Disclosures about Fair Value Measurements (ASU 2010-06). The provisions of ASU 2010-06 amend ASC Topic 820, Fair value measurements and Disclosures, (Topic 820) to require reporting entities to make new disclosures about recurring and nonrecurring fair value measurements including the amounts of and reasons for significant transfers into and out of Level 1 and Level 2 fair value measurements and separate disclosure of purchases, sales, issuances, and settlements in the reconciliation of Level 3 fair value measurements. ASU 2010-6 was effective for interim and annual reporting periods beginning after December 15, 2009, except for Level 3 reconciliation disclosures which are effective for interim and annual periods beginning after December 15, 2010.

3. Investments

a) Fixed maturities

The following tables present the fair values and amortized costs of and the gross unrealized appreciation (depreciation) related to fixed maturities as well as related OTTI recognized in AOCI.

As discussed in Note 3 c), if a credit loss is indicated on an impaired fixed maturity, an OTTI is considered to have occurred and the portion of the impairment not related to credit losses (non-credit OTTI) is recognized in OCI. Included in the "OTTI Recognized in AOCI" column above is the cumulative amount of non-credit OTTI recognized in OCI adjusted for subsequent sales, maturities, and redemptions. OTTI Recognized in AOCI does not include the impact of subsequent changes in fair value of the related securities. In periods subsequent to a recognition of OTTI in OCI, changes in the fair value of the related fixed maturities are reflected in Unrealized appreciation (depreciation) in the statement of comprehensive income. For the three months ended March 31, 2010, $63 million of net unrealized appreciation related to such securities is included in OCI. At March 31, 2010, and December 31, 2009, AOCI includes net unrealized depreciation of $156 million and $162 million, respectively, related to securities remaining in the investment portfolio at those dates for which ACE has recognized a non-credit OTTI.

The following table presents fixed maturities at March 31, 2010, and December 31, 2009, by contractual maturity. Expected maturities could differ from contractual maturities because borrowers may have the right to call or prepay obligations, with or without call or prepayment penalties.

b) Equity securities

The following table presents the fair value and cost of and gross unrealized appreciation (depreciation) related to equity securities at March 31, 2010, and December 31, 2009.

c) Net realized gains (losses)

The Company adopted provisions included in ASC Topic 320, Investments-Debt and Equity Securities, (Topic 320) related to the recognition and presentation of OTTI as at April 1, 2009. Under these provisions, when an OTTI related to a fixed maturity has occurred, ACE is required to record the OTTI in net income if the Company has the intent to sell the security or it is more likely than not that it will be required to sell the security. Further, in cases where the Company does not intend to sell the security and it is more likely than not that it will not be required to sell the security, ACE must evaluate the security to determine the portion of the impairment, if any, related to credit losses. If a credit loss is indicated, an OTTI is considered to have occurred and any portion of the OTTI related to credit losses must be reflected in net income while the portion of OTTI related to all other factors is recognized in OCI. For fixed maturities held to maturity, OTTI recognized in OCI is accreted from AOCI to the amortized cost of the fixed maturity prospectively over the remaining term of the securities. For fixed maturities, prior to this adoption, ACE was required to record OTTI in net income unless the Company had the intent and ability to hold the impaired security to recovery. These provisions do not have any impact on the accounting for OTTI for any other type of investment.

Each quarter, the Company reviews its securities in an unrealized loss position (impaired securities), including fixed maturities, securities lending collateral, equity securities, and other investments, to identify those impaired securities to be specifically evaluated for a potential OTTI.

For impaired fixed maturities, the Company assesses OTTI based on the provisions of Topic 320 as described above. The factors that the Company considers when determining if a credit loss exists related to a fixed maturity are discussed in "Evaluation of potential credit losses related to fixed maturities" below. Prior to the adoption, when evaluating fixed maturities for OTTI, the Company principally considered its ability and intent to hold the impaired security to the expected recovery period, the issuer's financial condition, and the Company's assessment (using available market information such as credit ratings) of the issuer's ability to make future scheduled principal and interest payments on a timely basis.

The Company reviews all non-fixed maturities for OTTI based on the following:

• the amount of time a security has been in a loss position and the magnitude of the loss position;
• the period in which cost is expected to be recovered, if at all, based on various criteria including economic conditions and other issuer-specific developments; and
• the Company's ability and intent to hold the security to the expected recovery period.

ACE, as a general rule, also considers that equity securities in an unrealized loss position for twelve consecutive months are impaired.

Evaluation of potential credit losses related to fixed maturities

ACE reviews each fixed maturity in an unrealized loss position to assess whether the security is a candidate for credit loss. Specifically, ACE considers credit rating, market price, and issuer-specific financial information, among other factors, to assess the likelihood of collection of all principal and interest as contractually due. Securities for which ACE determines that credit loss is likely are subjected to further analysis to estimate the credit loss recognized in net income, if any. In general, credit loss recognized in net income equals the difference between the security's amortized cost and the net present value of its projected future cash flows discounted at the effective interest rate implicit in the debt security. The specific methodologies and significant assumptions used by asset class are discussed below. All significant assumptions used in determining credit losses are subject to change as market conditions evolve.

U.S. Treasury and agency obligations (including agency mortgage-backed securities), foreign government obligations, and states, municipalities, and political subdivisions obligations

U.S. Treasury and agency obligations (including agency mortgage-backed securities), foreign government obligations, and states, municipalities, and political subdivisions obligations represent less than $60 million of gross unrealized loss at March 31, 2010. These securities were evaluated for credit loss primarily using qualitative assessments of the likelihood of credit loss considering credit rating of the issuers and level of credit enhancement, if any. ACE concluded that the high level of credit worthiness of the issuers coupled with credit enhancement, where applicable, supports recognizing no credit loss in net income.

Corporate securities

Projected cash flows for corporate securities (principally senior unsecured bonds) are driven primarily by assumptions regarding probability of default and also the timing and amount of recoveries associated with defaults. ACE develops these estimates using information based on market observable data, issuer-specific information, and credit ratings. ACE developed its default assumption by using historical default data by Moody's Investors Service (Moody's) rating category to calculate a 1-in-100 year probability of default, which results in a default assumption in excess of the historical mean default rate. ACE believes that use of a default assumption in excess of the historical mean is reasonable in light of recent market conditions. The following table presents default assumptions by Moody's rating category (historical mean default rate provided for comparison).

Consistent with management's approach to developing default rate assumptions considering recent market conditions, ACE assumed a 25 percent recovery rate (the par value of a defaulted security that will be recovered) across all rating categories rather than using Moody's historical mean recovery rate of 40 percent. ACE believes that use of a recovery rate assumption lower than the historical mean is reasonable in light of recent market conditions.

Application of the methodology and assumptions described above resulted in credit losses recognized in net income for corporate securities for the three months ended March 31, 2010, of $1 million, all of which relate to below investment grade securities.

Mortgage-backed securities

For mortgage-backed securities, credit impairment is assessed using a cash flow model that estimates the cash flows on the underlying mortgages, using the security-specific collateral and transaction structure. The model estimates cash flows from the underlying mortgage loans and distributes those cash flows to various tranches of securities, considering the transaction structure and any subordination and credit enhancements that exist in that structure. The cash flow model incorporates actual cash flows on the mortgage-backed securities through the current period and then projects the remaining cash flows using a number of assumptions, including default rates, prepayment rates, and loss severity rates (the par value of a defaulted security that will not be recovered) on foreclosed properties.

ACE develops specific assumptions using market data, where available, and includes internal estimates as well as estimates published by rating agencies and other third-party sources. ACE projects default rates by mortgage sector considering current underlying mortgage loan performance, generally assuming:

• lower loss severity for Prime sector bonds versus ALT-A, Sub-prime, and Option ARM sector bonds; and
• lower loss severity for older vintage securities versus more recent vintage securities, which reflects the recent decline in underwriting standards.

These estimates are extrapolated along a default timing curve to estimate the total lifetime pool default rate. Other assumptions used contemplate the actual collateral attributes, including geographic concentrations, rating agency loss projections, rating actions, and current market prices. If cash flow projections indicate that losses will exceed the credit enhancement for a given tranche, then the Company does not expect to recover its amortized cost basis and recognizes an estimated credit loss in net income.

The following table presents the significant assumptions used to estimate future cash flows for specific mortgage-backed securities evaluated for potential credit loss at March 31, 2010, by sector and vintage.

(1) Prime, ALT-A, and Sub-prime sector bonds are categorized based on credit worthiness of the borrower. Option ARM sector bonds are categorized based on the type of mortgage product, rather than credit worthiness of the borrower.

(2) Default rate and loss severity rate assumptions vary within a given sector and vintage depending upon the geographic concentration of the collateral underlying the bond and the level of serious delinquencies, among other factors.

Application of the methodology and assumptions described above resulted in credit losses recognized in net income for mortgage-backed securities for the three months ended March 31, 2010, of $17 million. Given the variation in ratings between major rating agencies for the securities for which a credit loss was recognized in net income, ACE does not believe it is useful to provide the credit loss split between investment grade and below investment grade.

The following table presents, for the periods indicated, the Net realized gains (losses) and the losses included in Net realized gains (losses) and OCI as a result of conditions which caused the Company to conclude the decline in fair value of certain investments was "other-than-temporary". The impairments recorded in net income related to fixed maturities for the three months ended March 31, 2010, were credit-related.

The following table presents, for the three months ended March 31, 2010, a roll forward of pre-tax credit losses related to fixed maturities for which a portion of OTTI was recognized in OCI.

d) Gross unrealized loss

At March 31, 2010, there were 3,301 fixed maturities out of a total of 18,770 fixed maturities in an unrealized loss position. The largest single unrealized loss in the fixed maturities was $25 million.  Credit spreads continued to tighten through the first quarter of 2010, resulting in a decrease in the gross unrealized losses in the investment portfolio. Fixed maturities in an unrealized loss position at March 31, 2010, were comprised of both investment grade and below investment grade securities for which fair value declined primarily due to widening credit spreads since the date of purchase and included non-agency mortgage-backed securities that suffered a decline in value since their original date of purchase.   

The following tables present, for all securities in an unrealized loss position at March 31, 2010, and December 31, 2009 (including securities on loan), the aggregate fair value and gross unrealized loss by length of time the security has continuously been in an unrealized loss position.

e) Restricted assets

The Company is required to maintain assets on deposit with various regulatory authorities to support its insurance and reinsurance operations. These requirements are generally promulgated in the statutory regulations of the individual jurisdictions. The assets on deposit are available to settle insurance and reinsurance liabilities. The Company also utilizes trust funds in certain large reinsurance transactions where the trust funds are set up for the benefit of the ceding companies and generally take the place of letter of credit (LOC) requirements. The Company also has investments in segregated portfolios primarily to provide collateral or guarantees for LOCs and derivative transactions. Included in restricted assets at March 31, 2010, are fixed maturities and short-term investments totaling $12.3 billion and cash of $117 million. The following table presents the components of the restricted assets at March 31, 2010, and December 31, 2009.

4. Assumed life reinsurance programs involving minimum benefit guarantees under annuity contracts

The following table presents income and expenses relating to guaranteed minimum death benefits (GMDB) and guaranteed minimum income benefits (GMIB) reinsurance for the periods indicated

At March 31, 2010, reported liabilities for GMDB and GMIB reinsurance were $209 million and $469 million, respectively, compared with $212 million and $559 million, respectively, at December 31, 2009. The reported liability for GMIB reinsurance of $469 million at March 31, 2010, and $559 million at December 31, 2009, includes a fair value derivative adjustment of $347 million and $443 million, respectively. Reported liabilities for both GMDB and GMIB reinsurance are determined using internal valuation models. Such valuations require considerable judgment and are subject to significant uncertainty. The valuation of these products is subject to fluctuations arising from, among other factors, changes in interest rates, changes in equity markets, changes in credit markets, changes in the allocation of the investments underlying annuitant's account values, and assumptions regarding future policyholder behavior. These models and the related assumptions are continually reviewed by management and enhanced, as appropriate, based upon improvements in modeling assumptions and availability of more information, such as market conditions and demographics of in-force annuities.

GMDB reinsurance

At March 31, 2010, and December 31, 2009, the Company's net amount at risk from its GMDB reinsurance programs was $3.5 billion and $3.8 billion, respectively.  For GMDB reinsurance programs, the net amount at risk is defined as the present value of future claim payments under the following assumptions:

• policy account values and guaranteed values are fixed at the valuation date (March 31, 2010, and December 31, 2009, respectively);

• there are no lapses or withdrawals;

• mortality according to 100 percent of the Annuity 2000 mortality table; and

• future claims are discounted in line with the discounting assumption used in the calculation of the benefit reserve averaging between three to four percent.

At March 31, 2010, if all of the Company's cedants' policyholders covered under GMDB reinsurance agreements were to die immediately, the total claim amount payable by the Company, taking into account all appropriate claims limits, would be approximately $1.2 billion. As a result of the annual claim limits on the GMDB reinsurance agreements, the claims payable are lower in this case than if all the policyholders were to die over time, all else equal.

GMIB reinsurance

At March 31, 2010, and December 31, 2009, the Company's net amount at risk from its GMIB reinsurance programs was $615 million and $683 million, respectively. For GMIB reinsurance programs, the net amount at risk is defined as the present value of future claim payments under the following assumptions:

• policy account values and guaranteed values are fixed at the valuation date (March 31, 2010, and December 31, 2009, respectively);

• there are no deaths, lapses, or withdrawals;

• policyholders annuitize at a frequency most disadvantageous to ACE (in other words, annuitization at a level that maximizes claims taking into account the treaty limits) under the terms of the Company's reinsurance contracts;

• for annuitizing policyholders, the GMIB claim is calculated using interest rates in line with those used in calculating the reserve; and

• future claims are discounted in line with the discounting assumption used in the calculation of the benefit reserve averaging between one to two percent.

The average attained age of all policyholders under all benefits reinsured, weighted by the guaranteed value of each reinsured policy, is approximately 66.

5. Commitments, contingencies, and guarantees

a) Derivative instruments

Derivative instruments employed

The Company maintains positions in derivative instruments such as futures, options, swaps, and foreign currency forward contracts for which the primary purposes are to manage duration and foreign currency exposure, yield enhancement, or to obtain an exposure to a particular financial market. Along with convertible bonds and to be announced mortgage-backed securities (TBA), discussed below, these are the most numerous and frequent derivative transactions.

ACE maintains positions in convertible bond investments that contain embedded derivatives. In addition, the Company purchases TBAs as part of its investing activities. These securities are included within the Company's fixed maturities available for sale (FM AFS) portfolio.

Under reinsurance programs covering living benefit guarantees, the Company assumes the risk of GMIBs associated with variable annuity contracts. The GMIB risk is triggered if, at the time the contract holder elects to convert the accumulated account value to a periodic payment stream (annuitize), the accumulated account value is not sufficient to provide a guaranteed minimum level of monthly income. The Company's GMIB reinsurance product meets the definition of a derivative instrument. Benefit reserves in respect of GMIBs are classified as Future policy benefits (FPB) while the fair value derivative adjustment is classified within Accounts payable, accrued expenses, and other liabilities (AP). The Company also maintains positions in exchange-traded equity futures contracts and options on equity market futures to limit equity and interest rate exposure in the GMDB and GMIB block of business.

In relation to certain long- and short-term debt issuances, the Company has entered into interest rate swap transactions for the purpose of either fixing or reducing borrowing costs. Although the use of these interest rate swaps has the economic effect of fixing or reducing borrowing costs on a net basis, gross interest expense on the related debt issuances is included in Interest expense while the settlements related to the interest rate swaps are reflected in Net realized gains (losses) in the consolidated statements of operations. ACE buys credit default swaps to mitigate global credit risk exposure, primarily related to reinsurance recoverable.

The Company carries all derivative instruments at fair value with changes in fair value recorded in Net realized gains (losses) in the consolidated statements of operations. None of the derivative instruments are used as hedges for accounting purposes.

The following table presents the balance sheet locations, fair values in an asset or (liability) position, and notional values/payment provisions of the Company's derivative instruments at March 31, 2010, and December 31, 2009.

(1)Note that the payment provision related to GMIB is the net amount at risk. The concept of a notional value does not apply to the GMIB reinsurance contracts.

Credit risk-related contingent features

Certain of the Company's derivative instruments contain provisions that impact the amount of collateral that ACE is required to post and that allow the contract counterparty to cancel the contract contingent on the Company's, and in certain cases subsidiaries of the Company's, senior debt ratings (Ratings). The aggregate fair value of derivative instruments in a liability position with credit risk-related contingent features at March 31, 2010, was $27 million. In connection with these contracts, ACE has posted collateral of $17 million at March 31, 2010.  The amount of collateral that ACE is required to post under these contracts would increase should the Company's Ratings deteriorate. At March 31, 2010, the maximum amount of collateral that the Company would be required to post in respect of these derivative instruments, based on the contractual Ratings-based scales, is $27 million. If ACE's Ratings fall to BBB- as measured by Standard and Poor's (S&P) or Baa3 as measured by Moody's, the contract counterparties would be able to cancel the contracts and they would be settled at fair value on the date of cancellation.

Derivative instrument objectives

(i) Foreign currency exposure management

The Company uses foreign currency forward contracts (forwards) to minimize the effect of fluctuating foreign currencies. The forwards purchased are not specifically identifiable against cash, any single security, or groups of securities denominated in those currencies and, therefore, do not qualify as hedges for financial reporting purposes.

(ii) Duration management and market exposure

Futures

Futures contracts give the holder the right and obligation to participate in market movements, determined by the index or underlying security on which the futures contract is based. Settlement is made daily in cash by an amount equal to the change in value of the futures contract times a multiplier that scales the size of the contract. Exchange-traded bond and note futures contracts are used in fixed maturity portfolios as substitutes for ownership of the bonds and notes without significantly increasing the risk in the portfolio. Investments in futures contracts may be made only to the extent that there are assets under management not otherwise committed. Exchange-traded equity futures contracts are used to limit exposure to a severe equity market decline, which would cause an increase in expected claims and therefore, reserves for GMDB and GMIB reinsurance business.

Options

An option contract conveys to the holder the right, but not the obligation, to purchase or sell a specified amount or value of an underlying security at a fixed price. Option contracts are used in the investment portfolio as protection against unexpected shifts in interest rates, which would affect the duration of the fixed maturity portfolio. By using options in the portfolio, the overall interest rate sensitivity of the portfolio can be reduced. Option contracts may also be used as an alternative to futures contracts in the Company's synthetic strategy as described above. Another use for option contracts is to limit exposure to a severe equity market decline, which would cause an increase in expected claims and therefore, reserves for GMDB and GMIB reinsurance business. The price of an option is influenced by the underlying security, expected volatility, time to expiration, and supply and demand.

The credit risk associated with the above derivative financial instruments relates to the potential for non-performance by counterparties. Although non-performance is not anticipated, in order to minimize the risk of loss, management monitors the credit worthiness of its counterparties. The performance of exchange-traded instruments is guaranteed by the exchange on which they trade. For non-exchange-traded instruments, the counterparties are principally banks which must meet certain criteria according to the Company's investment guidelines.

Interest rate swaps

An interest rate swap is a contract between two counterparties in which interest payments are made based on a notional principal amount, which itself is never paid or received. Under the terms of an interest rate swap, one counterparty makes interest payments based on a fixed interest rate and the other counterparty's payments are based on a floating rate. Interest rate swap contracts are used occasionally in the investment portfolio as protection against unexpected shifts in interest rates, which would affect the fair value of the fixed maturity portfolio. By using interest rate swaps in the portfolio, the overall duration or interest rate sensitivity of the portfolio can be reduced. The Company also employs interest rate swaps related to certain debt issuances for the purpose of either fixing and/or reducing borrowing costs.

Credit default swaps

A credit default swap is a bilateral contract under which two counterparties agree to isolate and separately trade the credit risk of at least one third-party reference entity. Under a credit default swap agreement, a protection buyer pays a periodic fee to a protection seller in exchange for a contingent payment by the seller upon a credit event (such as a default or failure to pay) related to the reference entity. When a credit event is triggered, the protection seller pays the protection buyer the difference between the fair value of assets and the principal amount. The Company has purchased a credit default swap to mitigate its global credit risk exposure to one of its reinsurers.

(iii) Convertible security investments

A convertible bond is a debt instrument that can be converted into a predetermined amount of the issuer's equity at certain times prior to the bond's maturity. The convertible option is an embedded derivative within the fixed maturity host instruments which are classified in the investment portfolio as available for sale. The Company purchases convertible bonds for their total return and not specifically for the conversion feature.

(iv) TBA

By acquiring a TBA, the Company makes a commitment to purchase a future issuance of mortgage-backed securities. For the period between purchase of the TBA and issuance of the underlying security, the Company's position is accounted for as a derivative in the consolidated financial statements. The Company purchases TBAs both for their total return and for the flexibility they provide related to ACE's mortgage-backed security strategy.

(v) GMIB

Under the GMIB program, as the assuming entity, the Company is obligated to provide coverage until the expiration of the underlying annuities. Premiums received under the reinsurance treaties are classified as premium. Expected losses allocated to premiums received are classified as future policy benefits and valued similar to GMDB reinsurance. Other changes in fair value, principally arising from changes in expected losses allocated to expected future premiums, are classified as Net realized gains (losses). Fair value represents exit price and thus, includes a risk margin. The Company may recognize a realized loss for other changes in fair value due to adverse changes in the capital markets (i.e., declining interest rates and/or declining equity markets) and changes in policyholder behavior (i.e., increased annuitization or decreased lapse rates) although the Company expects the business to be profitable. The Company believes this presentation provides the most meaningful disclosure of changes in the underlying risk within the GMIB reinsurance programs for a given reporting period.

b) Other investments

Included in Other investments are investments in limited partnerships and partially-owned investment companies with a carrying value of $949 million. In connection with these investments, the Company has commitments that may require funding of up to $669 million over the next several years.

c) Taxation

The Internal Revenue Service (IRS) completed its field examination of the Company's federal tax returns for 2002, 2003, and 2004 during the third quarter of 2007, and has proposed several adjustments principally involving transfer pricing and other insurance-related tax deductions. The Company subsequently filed a written protest with the IRS and the case is currently being reviewed by the IRS Appeals Division. The Company expects the appeals process to be completed within the next 12 months. The IRS is currently conducting an examination of the Company's 2005 through 2007 tax returns and the examination is expected to be completed during 2010. While it is reasonably possible that a significant change in the Company's unrecognized tax benefits could occur in the next 12 months, the Company believes that the outcome of the appeal and the current examination will not have a material impact on ACE's financial condition. With few exceptions, the Company's significant U.K. subsidiaries remain subject to examination for tax years 2007 and later.

d) Legal proceedings

(i) Claims and other litigation

The Company's insurance subsidiaries are subject to claims litigation involving disputed interpretations of policy coverage and, in some jurisdictions, direct actions by allegedly-injured persons seeking damages from policyholders. These lawsuits, involving claims on policies issued by the Company's subsidiaries, which are typical to the insurance industry in general and in the normal course of business, are considered in the Company's loss and loss expense reserves. In addition to claims litigation, the Company and its subsidiaries are subject to lawsuits and regulatory actions in the normal course of business that do not arise from, or directly relate to, claims on insurance policies. This category of business litigation typically involves, amongst other things, allegations of underwriting errors or misconduct, employment claims, regulatory activity, or disputes arising from business ventures. In the opinion of ACE's management, ACE's ultimate liability for these matters is not likely to have a material adverse effect on ACE's consolidated financial condition, although it is possible that the effect could be material to ACE's consolidated results of operations for an individual reporting period.

(ii) Business practices litigation

Beginning in 2004, ACE and its subsidiaries and affiliates received numerous subpoenas, interrogatories, and civil investigative demands in connection with certain investigations of insurance industry practices. These inquiries were issued by a number of attorneys general, state departments of insurance, and other authorities, including the New York Attorney General (NYAG) and the Pennsylvania Insurance Department. Such inquiries concerned underwriting practices and non-traditional or loss mitigation insurance products.

On April 25, 2006, ACE reached a settlement with the Attorneys General of New York, Illinois, and Connecticut and the New York Insurance Department pursuant to which ACE received from these authorities an Assurance of Discontinuance. On May 9, 2007, ACE and the Pennsylvania Insurance Department (Department) and the Pennsylvania Office of Attorney General (OAG) entered into a settlement agreement. This settlement agreement resolved the issues raised by the Department and the OAG arising from their investigation of ACE's underwriting practices and contingent commission payments. On October 24, 2007, ACE entered into a settlement agreement with the Attorneys General of Florida, Hawaii, Maryland, Massachusetts, Michigan, Oregon, Texas, West Virginia, the District of Columbia, and the Florida Department of Financial Services and Office of Insurance Regulation. The agreement resolved investigations of ACE's underwriting practices and contingent commission payments.

In June 2008, in an action filed by the NYAG against another insurer, a New York court held that "[c]ontingent commission agreements between brokers and insurers are not illegal, and, in the absence of a special relationship between parties, defendants[s] had no duty to disclose the existence of the contingent commission agreement." New York v. Liberty Mut. Ins. Co., 52 A.D. 3d 378, 379 (2008) (citing Hersch v. DeWitt Stern Group, Inc., 43 A.D. 3d 644, 645 (2007). In February 2010, the NYAG amended its agreement with the country's three largest insurance brokers, eliminating the ban on contingent commissions that was levied in 2005.

ACE, ACE INA Holdings, Inc., and ACE USA, Inc., along with a number of other insurers and brokers, were named in a series of federal putative nationwide class actions brought by insurance policyholders. The Judicial Panel on Multidistrict Litigation (JPML) consolidated these cases in the District of New Jersey. On August 1, 2005, plaintiffs in the New Jersey consolidated proceedings filed two consolidated amended complaints – one concerning commercial insurance and the other concerning employee benefit plans. The employee benefit plans litigation against ACE has been dismissed.

In the commercial insurance complaint, the plaintiffs named ACE, ACE INA Holdings, Inc., ACE USA, Inc., ACE American Insurance Co., Illinois Union Insurance Co., and Indemnity Insurance Co. of North America. They allege that certain brokers and insurers, including certain ACE entities, conspired to increase premiums and allocate customers through the use of "B" quotes and contingent commissions. In addition, the complaints allege that the broker defendants received additional income by improperly placing their clients' business with insurers through related wholesale entities that acted as intermediaries between the broker and insurer. Plaintiffs also allege that broker defendants tied the purchase of primary insurance to the placement of such coverage with reinsurance carriers through the broker defendants' reinsurance broker subsidiaries. The complaint asserts the following causes of action against ACE: Federal Racketeer Influenced and Corrupt Organizations Act (RICO), federal antitrust law, state antitrust law, aiding and abetting breach of fiduciary duty, and unjust enrichment.

In 2006 and 2007, the Court dismissed plaintiffs' first two attempts to properly plead a case without prejudice and permitted plaintiffs one final opportunity to re-plead. The amended complaint, filed on May 22, 2007, purported to add several new ACE defendants: ACE Group Holdings, Inc., ACE US Holdings, Inc., Westchester Fire Insurance Company, INA Corporation, INA Financial Corporation, INA Holdings Corporation, ACE Property and Casualty Insurance Company, and Pacific Employers Insurance Company. Plaintiffs also added a new antitrust claim against Marsh, ACE, and other insurers based on the same allegations as the other claims but limited to excess casualty insurance. On June 21, 2007, defendants moved to dismiss the amended complaint and moved to strike the new parties. The Court granted defendants' motions and dismissed plaintiffs' antitrust and RICO claims with prejudice on August 31, 2007, and September 28, 2007, respectively. The Court also declined to exercise supplemental jurisdiction over plaintiffs' state law claims and dismissed those claims without prejudice. On October 10, 2007, plaintiffs filed a Notice of Appeal of the antitrust and RICO rulings to the United States Court of Appeals for the Third Circuit. The parties fully briefed the appeal and argued before the Third Circuit on April 21, 2009. The court took the case under advisement, but did not indicate when it would issue a decision.

There are a number of federal actions brought by policyholders based on allegations similar to the allegations in the consolidated federal actions that were filed in, or transferred to, the United States District Court for the District of New Jersey for coordination. All proceedings in these actions are currently stayed.

• New Cingular Wireless Headquarters LLC et al. v. Marsh & McLennan Companies, Inc. et al. (Case No. 06-5120; D.N.J.), was originally filed in the Northern District of Georgia on April 4, 2006. ACE, ACE American Ins. Co., ACE USA, Inc., ACE Bermuda Ins. Co. Ltd., Illinois Union Ins. Co., Pacific Employers Ins. Co., and Lloyd's of London Syndicate 2488 AGM, along with a number of other insurers and brokers, are named.

• Avery Dennison Corp. v. Marsh & McLennan Companies, Inc. et al. (Case No. 07-00757; D.N.J.) was filed on February 13, 2007. ACE, ACE INA Holdings, Inc., ACE USA, Inc., and ACE American Insurance Co., along with a number of other insurers and brokers, are named.

• Henley Management Co., Inc. et al v. Marsh, Inc. et al. (Case No. 07-2389; D.N.J.) was filed on May 27, 2007. ACE USA, Inc., along with a number of other insurers and Marsh, are named.

• Lincoln Adventures LLC et al. v. Those Certain Underwriters at Lloyd's, London Members of Syndicates 0033 et al. (Case No. 07-60991; D.N.J.) was originally filed in the Southern District of Florida on July 13, 2007. Supreme Auto Transport LLC et al. v. Certain Underwriters of Lloyd's of London, et al. (Case No. 07-6703; D.N.J.) was originally filed in the Southern District of New York on July 25, 2007. Lloyd's of London Syndicate 2488 AGM, along with a number of other Lloyd's of London Syndicates and various brokers, are named in both actions. The allegations in these putative class-action lawsuits are similar to the allegations in the consolidated federal actions identified above, although these lawsuits focus on alleged conduct within the London insurance market.

• Sears, Roebuck & Co. et al. v. Marsh & McLennan Companies, Inc. et al. (Case No. 07-2535; D.N.J.) was originally filed in the Northern District of Georgia on October 12, 2007. ACE American Insurance Co., ACE Bermuda Insurance Ltd., and Westchester Surplus Lines Insurance Co., along with a number of other insurers and brokers, are named.

Three cases have been filed in state courts with allegations similar to those in the consolidated federal actions described above.

• Van Emden Management Corporation v. Marsh & McLennan Companies, Inc., et al. (Case No. 05-0066A; Superior Court of Massachusetts), a class action in Massachusetts, was filed on January 13, 2005. Illinois Union Insurance Company is named. The Van Emden case has been stayed pending resolution of the consolidated proceedings in the District of New Jersey or until further order of the Court.

• Office Depot, Inc. v. Marsh & McLennan Companies, Inc. et al. (Case No. 502005CA004396; Circuit Court of the 15th Judicial Circuit in Palm Beach County Florida), a Florida state action, was filed on June 22, 2005. ACE American Insurance Co. is named. The trial court originally stayed this case, but the Florida Court of Appeals later remanded and the trial court declined to grant another stay. The court has denied motions to dismiss, and ACE American Ins. Co. has filed an answer. Discovery is ongoing. Trial is scheduled for January 2011.

• State of Ohio, ex. rel. Marc E. Dann, Attorney General v. American Int'l Group, Inc. et al. (Case No. 07-633857; Court of Common Pleas in Cuyahoga County, Ohio) is an Ohio state action filed by the Ohio Attorney General on August 24, 2007. ACE INA Holdings, Inc., ACE American Insurance Co., ACE Property & Casualty Insurance Co., Insurance Company of North America, and Westchester Fire Insurance Co., along with a number of other insurance companies and Marsh, are named. Defendants filed motions to dismiss in November 2007. On July 2, 2008, the court denied all of the defendants' motions. Discovery is ongoing. Trial will likely occur in early 2011.

ACE was named in four putative securities class action suits following the filing of a civil suit against Marsh by the NYAG on October 14, 2004. The suits were consolidated by the JPML in the Eastern District of Pennsylvania and the Court appointed Sheet Metal Workers' National Pension Fund and Alaska Ironworkers Pension Trust as lead plaintiffs. Lead plaintiffs filed a consolidated amended complaint on September 30, 2005, naming ACE, Evan G. Greenberg, Brian Duperreault, and Philip V. Bancroft as defendants. Plaintiffs allege that ACE's public statements and securities filings should have revealed that insurers, including certain ACE entities, and brokers allegedly conspired to increase premiums and allocate customers through the use of "B" quotes and contingent commissions and that ACE's revenues and earnings were inflated by these practices. Plaintiffs assert claims solely under Section 10(b) of the Securities Exchange Act of 1934 (the Exchange Act), Rule 10(b)-5 promulgated thereunder, and Section 20(a) of the Securities Act (control person liability). In 2005, ACE and the individual defendants filed a motion to dismiss. The Court heard oral argument on November 10, 2008, but did not rule on the motion. On December 16, 2008, the parties entered into a Stipulation of Settlement in which the parties agreed – contingent upon Court approval – that ACE would pay the plaintiffs $1.95 million in exchange for a full release of all claims. On June 9, 2009, the Court approved the settlement and dismissed the multidistrict litigation (including the four underlying suits) with prejudice.

ACE, ACE USA, Inc., ACE INA Holdings, Inc., and Evan G. Greenberg, as a former officer and director of AIG and current officer and director of ACE, are named in one or both of two derivative cases brought by certain shareholders of AIG. One of the derivative cases was filed in Delaware Chancery Court, and the other was filed in federal court in the Southern District of New York. The allegations against ACE concern the alleged bid rigging and contingent commission scheme as similarly alleged in the federal commercial insurance cases. Plaintiffs assert the following causes of action against ACE: breach of fiduciary duty, aiding and abetting breaches of fiduciary duties, unjust enrichment, conspiracy, and fraud. In Delaware, the shareholder plaintiffs filed an amended complaint (their third pleading effort), on April 14, 2008, which drops Evan Greenberg as a defendant (plaintiffs in the New York action subsequently dismissed Evan Greenberg as well). On June 13, 2008, ACE filed a motion to dismiss, and on April 20, 2009, the court heard oral argument on the motion. On June 17, 2009, the Court dismissed all claims against ACE with prejudice; final judgment in favor of ACE was entered on July 13, 2009. The derivative plaintiffs appealed and argument was held before a three judge panel of the Delaware Supreme Court on February 17, 2010. On February 22, 2010, the three judge panel ordered further oral argument to the Court en banc without scheduling a date. The New York derivative action is currently stayed.

In all of the lawsuits described above, plaintiffs seek compensatory and in some cases special damages without specifying an amount. As a result, ACE cannot at this time estimate its potential costs related to these legal matters and, accordingly, no liability for compensatory damages has been established in the consolidated financial statements.

ACE's ultimate liability for these matters is not likely to have a material adverse effect on ACE's consolidated financial condition, although it is possible that the effect could be material to ACE's consolidated results of operations for an individual reporting period.

(iii)  Legislative activity

The State of New York, as part of the 2009-10 State budget, has adopted language that requires an insurer which (1) paid to the Workers' Compensation Board (WCB) various statutory assessments in an amount less than that insurer "collected" from insured employers in a given year and (2) "has identified and held any funds collected but not paid to the WCB, as measurable and available, as of January 1, 2009" to pay retroactive assessments to the WCB. The language, and impact, of this new law is at present uncertain because it uses terms and dates that are not readily identifiable with respect to insurers' statutory financial statements and because the State has not promulgated implementing regulations or other explanatory materials. The Company's understanding is that the law is intended to address certain inconsistencies in the New York State laws regulating the calculation of workers' compensation assessments by insurance carriers and the remittance of those funds to the State. In July 2009, ACE received a subpoena from the NYAG requesting documents related to these issues, and in October 2009, ACE received a request from the WCB asking ACE to explain whether or not it was an "affected carrier" under the new law.  In addition, the New York State legislature, as part of the 2010-11 State budget, is considering language that, if enacted, would require an insurer who paid to the WCB various statutory assessments in an amount less than that insurer "collected" from insured employers for the period April 1, 2008, through March 31, 2009, to pay such "excess assessment funds" to the WCB. Although the Company cannot at this time predict the interpretation that will be afforded the language in the 2009-10 State budget, and cannot predict the outcome of the legislative process with regard to the language in the proposed 2010-11 State budget, ACE is confident that it has complied with the law governing workers' compensation surcharges and assessments. ACE has established a contingency based on the Company's best estimate of the potential liability that could result from the legislation or other events surrounding this topic, based on the facts and circumstances at this time. Such contingency will be increased or decreased as circumstances develop. The Company does not expect these events to have a material impact on its financial condition or results of operations.

6. Shareholders' equity

All Common Shares of the Company are registered common shares under Swiss corporate law. Though the par value of Common Shares is stated in Swiss francs, the Company continues to use U.S. dollars as its reporting currency for preparing the consolidated financial statements. Under Swiss corporate law, dividends, including distributions through a reduction in par value (par value distributions), must be declared by ACE in Swiss francs though dividend payments are made by the Company in U.S. dollars. For the foreseeable future, subject to shareholder approval, the Company expects to pay dividends as a repayment of share capital in the form of a reduction in par value or qualified paid-in capital, which would not be subject to Swiss withholding tax. For the three months ended March 31, 2010 and 2009, dividends declared per Common Share amounted to CHF 0.33 ($0.31) and CHF 0.30 ($0.26), respectively.  The par value distribution in the three months ended March 31, 2010, is reflected as such through Common Shares in the consolidated statement of shareholders' equity and had the effect of reducing the par value per Common Share to CHF 31.55.

Under Swiss corporate law, the Company may not generally issue Common Shares below their par value.  In the event there is a need to raise common equity at a time when the trading price of the Company's Common Shares is below par value, the Company will need to obtain shareholder approval to decrease the par value of the Common Shares.

Common Shares in treasury are used principally for issuance upon the exercise of employee stock options. At March 31, 2010, 1,547,923 Common Shares remain in treasury after net shares redeemed under employee share-based compensation plans.

7. Share-based compensation

During 2004, the Company established the ACE Limited 2004 Long-Term Incentive Plan (the 2004 LTIP). The Company's 2004 LTIP provides for grants of both incentive and non-qualified stock options principally at an option price per share of 100 percent of the fair value of the Company's Common Shares on the date of grant. Stock options are generally granted with a 3-year vesting period and a 10-year term. The stock options vest in equal annual installments over the respective vesting period, which is also the requisite service period. On February 25, 2010, the Company granted 2,114,706 stock options with a weighted-average grant date fair value of $12.08. The fair value of the options issued is estimated on the date of grant using the Black-Scholes option pricing model.

The Company's 2004 LTIP also provides for grants of restricted stock and restricted stock units. The Company generally grants restricted stock and restricted stock units with a 4-year vesting period, based on a graded vesting schedule. The restricted stock is granted at market close price on the day of grant. On February 25, 2010, the Company granted 2,187,844 restricted stock awards and 320,766 restricted stock units to officers of the Company and its subsidiaries with a grant date fair value of $50.37. Each restricted stock unit represents the Company's obligation to deliver to the holder one Common Share upon vesting.

8. Fair value measurements

Fair value hierarchy

The provisions of Topic 820 define fair value as the price to sell an asset or transfer a liability in an orderly transaction between market participants and establishes a three-level valuation hierarchy in which inputs into valuation techniques used to measure fair value are classified. The fair value hierarchy gives the highest priority to quoted prices in active markets and the lowest priority to unobservable data. Inputs in Level 1 are unadjusted quoted prices for identical assets or liabilities in active markets. Level 2 includes inputs other than quoted prices included within Level 1 that are observable for assets or liabilities either directly or indirectly. Level 2 inputs include, among other items, quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets and liabilities in markets that are not active, and inputs other than quoted prices that are observable for the asset or liability such as interest rates and yield curves. Level 3 inputs are unobservable and reflect management's judgments about assumptions that market participants would use in pricing an asset or liability. A financial instrument's categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. ACE makes decisions regarding the categorization of assets or liabilities within the valuation hierarchy based on the inputs used to determine respective fair values at the balance sheet date. Accordingly, transfers between levels within the valuation hierarchy are determined on the same basis.

The Company utilizes one or more pricing services to obtain fair value measurements for the majority of the investment securities it holds. Based on management's understanding of the methodologies used by these pricing services, all applicable investments have been valued in accordance with GAAP valuation principles. The following is a description of the valuation techniques and inputs used to determine fair values for the Company's financial instruments carried or disclosed at fair value, as well as the general classification of such financial instruments pursuant to the valuation hierarchy.

Fixed maturities

The Company utilizes pricing services to estimate fair value measurements for the majority of its fixed maturities. The pricing services utilize market quotations for fixed maturities that have quoted prices in active markets; such securities are classified within Level 1. For fixed maturities other than U.S. Treasury securities that generally do not trade on a daily basis, the pricing services prepare estimates of fair value measurements using their pricing applications, which include available relevant market information, benchmark curves, benchmarking of like securities, sector groupings, and matrix pricing. Additional valuation factors that can be taken into account are nominal spreads, dollar basis, and liquidity adjustments. The pricing services evaluate each asset class based on relevant market and credit information, perceived market movements, and sector news. The market inputs utilized in the pricing evaluation, listed in the approximate order of priority include: benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, reference data, and industry and economic events. The extent of the use of each input is dependant on the asset class and the market conditions. Additionally, given the asset class, the priority of the use of inputs may change or some market inputs may not be relevant. The overwhelming majority of fixed maturities are classified within Level 2 because the most significant inputs used in the pricing techniques are observable. Fixed maturities for which pricing is unobservable are classified within Level 3.

Equity securities

Equity securities with active markets are classified within Level 1 as fair values are based on quoted market prices. For non-public equity securities, fair values are based on market valuations and are classified within Level 2.

Short-term investments

Short-term investments, which comprise securities due to mature within one year of the date of purchase, that are traded in active markets are classified within Level 1 as fair values are based on quoted market prices. Securities such as commercial paper and discount notes are classified within Level 2 because these securities are typically not actively traded due to their approaching maturity and, as such, their cost approximates par value.

Securities lending collateral

The underlying assets included in Securities lending collateral are fixed maturities which are classified in the valuation hierarchy on the same basis as the Company's other fixed maturities. Excluded from the valuation hierarchy is the corresponding liability related to the Company's obligation to return the collateral plus interest.

Other investments

Fair values for the majority of Other investments including investments in partially-owned investment companies, investment funds, and limited partnerships are based on their respective net asset values or equivalent (NAV). The majority of these investments, for which the Company has used NAV as a practical expedient to measure fair value, are classified within Level 3 because either ACE will never have the contractual option to redeem the investment or will not have the contractual option to redeem the investments in the near term. The remainder of such investments are classified within Level 2. Equity securities and fixed maturities held in rabbi trusts maintained by the Company for deferred compensation plans, and included in Other investments, are classified within the valuation hierarchy on the same basis as the Company's other equity securities and fixed maturities.

Investments in partially-owned insurance companies

Fair values for investments in partially-owned insurance companies based on the financial statements provided by those companies used for equity accounting are classified within Level 3.

Investment derivative instruments

For actively traded investment derivative instruments, including futures, options, and exchange-traded forward contracts, the Company obtains quoted market prices to determine fair value. As such, these instruments are included within Level 1.

Guaranteed minimum income benefits

The liability for GMIBs arises from the Company's life reinsurance programs covering living benefit guarantees whereby the Company assumes the risk of GMIBs associated with variable annuity contracts. For GMIB reinsurance, ACE estimates fair value using an internal valuation model which includes current market information and estimates of policyholder behavior. All of the treaties contain claim limits, which are factored into the valuation model. The fair value depends on a number of inputs, including changes in interest rates, changes in equity markets, credit risk, current account value, changes in market volatility, expected annuitization rates, changes in policyholder behavior, and changes in policyholder mortality.  The model and related assumptions are continuously re-evaluated by management and enhanced, as appropriate, based upon additional experience obtained related to policyholder behavior and availability of more information, such as market conditions and demographics of in-force annuities. Based on the quarterly reserve review, no material changes were made to actuarial or behavioral assumptions during the quarter ended March 31, 2010. The most significant policyholder behavior assumptions include lapse rates and annuitization rates using the guaranteed benefit (GMIB annuitization rate). Assumptions regarding lapse rates and GMIB annuitization rates differ by treaty but the underlying methodology to determine rates applied to each treaty is comparable. The assumptions regarding lapse and GMIB annuitization rates determined for each treaty are based on a dynamic calculation that uses several underlying factors. A lapse rate is the percentage of in-force policies surrendered in a given calendar year. All else equal, as lapse rates increase, ultimate claim payments will decrease. The GMIB annuitization rate is the percentage of policies for which the policyholder will elect to annuitize using the guaranteed benefit provided under the GMIB. All else equal, as GMIB annuitization rates increase, ultimate claim payments will increase, subject to treaty claim limits. The effect of changes in key market factors on assumed lapse and annuitization rates reflect emerging trends using data available from cedants. For treaties with limited experience, rates are established in line with data received from other ceding companies adjusted as appropriate with industry estimates. The Company views the variable annuity reinsurance business as having a similar risk profile to that of catastrophe reinsurance, with the probability of a cumulative long-term economic net loss relatively small at the time of pricing. However, adverse changes in market factors and policyholder behavior will have an adverse impact on net income, which may be material. Because of the significant use of unobservable inputs including policyholder behavior, GMIB reinsurance is classified within Level 3.

Short- and long-term debt and trust preferred securities

Where practical, fair values for short-term debt, long-term debt, and trust preferred securities are estimated using discounted cash flow calculations based principally on observable inputs including the Company's incremental borrowing rates, which reflect ACE's credit rating, for similar types of borrowings with maturities consistent with those remaining for the debt being valued. As such, these instruments are classified within Level 2.

Other derivative instruments

The Company maintains positions in other derivative instruments including exchange-traded equity futures contracts and option contracts designed to limit exposure to a severe equity market decline, which would cause an increase in expected claims and, therefore, reserves for GMDB and GMIB reinsurance business. The Company's position in exchange-traded equity futures contracts is classified within Level 1. The fair value of the majority of the Company's remaining positions in other derivative instruments is based on significant observable inputs including equity security and interest rate indices. Accordingly, these are classified within Level 2. The Company's position in credit default swaps is typically included within Level 3.

The following tables present, by valuation hierarchy, the financial instruments carried or disclosed at fair value, and measured on a recurring basis, at March 31, 2010, and December 31, 2009.