INTRODUCTION

Ambac Financial Group, Inc., headquartered in New York City, is a holding company incorporated in the state of Delaware. Ambac was incorporated on April 29, 1991. On November 8, 2010, Ambac filed a voluntary petition for relief under Chapter 11 of the United States Bankruptcy Code (“Bankruptcy Code”) in the United States Bankruptcy Court for the Southern District of New York (“Bankruptcy Court”). Ambac will continue to operate in the ordinary course of business as “debtor-in-possession” under the jurisdiction of the Bankruptcy Court and in accordance with the applicable provisions of the Bankruptcy Code and the orders of the Bankruptcy Court. Ambac Assurance is Ambac’s principal operating subsidiary. Ambac Assurance is a financial guarantee insurer whose financial strength was formerly rated triple-A by each of the major rating agencies and which provided financial guarantees and financial services to clients in both the public and private sectors around the world.

The deterioration of Ambac Assurance’s financial condition resulting from losses in its insured portfolio and the resulting downgrades of Ambac Assurance’s financial strength ratings have prevented it from being able to write new business. An inability to write new business will negatively impact Ambac’s future operations and financial results. Ambac Assurance’s ability to pay dividends, and as a result Ambac’s liquidity, has been significantly restricted by the deterioration of Ambac Assurance’s financial condition, by the rehabilitation of the Segregated Account (as hereinafter defined and described in more detail below) and by the terms of the Settlement Agreement (as hereinafter defined). Refer to “2010 Overview” located in Note 1 to the Consolidated Financial Statements in Item 8 of this Form 10-K for further discussion of Ambac’s bankruptcy, the creation and rehabilitation of the Segregated Account and the Settlement Agreement with the counterparties of CDO of ABS transactions.

Ambac’s principal business strategy is to reorganize its capital structure and financial obligations through the bankruptcy process and to increase the residual value of its financial guarantee business by mitigating losses on poorly performing transactions (via the pursuit of recoveries in respect of paid claims, commutations of policies and repurchases of surplus notes issued in respect of claims) and maximizing the return on its investment portfolio. Ambac does not currently anticipate generating any new business. The execution of such strategy with respect to Segregated Account Policies will be subject to the authority of the rehabilitator of the Segregated Account to control the management of the Segregated Account. In exercising such authority, the rehabilitator will act for the benefit of policyholders, and will not take into account the interests of Ambac. Similarly, by operation of the contracts executed in connection with the establishment, and subsequent rehabilitation, of the Segregated Account, the rehabilitator retains rights to oversee and approve certain actions taken in respect of Ambac Assurance. This oversight by the rehabilitator could impair Ambac’s ability to execute the foregoing strategy.

BUSINESS SEGMENTS

Ambac has two reportable business segments: Financial Guarantee and Financial Services. Each of these businesses is conducted by Ambac Assurance and/or its subsidiaries and is therefore subject to control of, or oversight by the Office of the Commissioner of Insurance of the State of Wisconsin (“OCI”). Ambac is no longer originating or competing for new business and is currently managing the runoff of these portfolios.

Ambac provided financial guarantee insurance for public and structured finance obligations solely through the insurance operations of Ambac Assurance and its wholly owned subsidiary, Ambac Assurance UK, Ltd (“Ambac UK”). Ambac also has another wholly-owned subsidiary, Everspan, it had intended to reactivate for purposes of writing financial guarantee business; however, this effort was postponed indefinitely due to our inability to raise third party capital. While Ambac Assurance historically had AAA financial strength ratings, its

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ratings have been downgraded multiple times, beginning in 2008. Ambac Assurance currently has a Caa2 financial strength from Moody’s and has requested and received a withdrawal of its ratings from S&P. As described above, our activities in these sectors has been limited to loss mitigation and the recovery of residual value in Ambac Assurance as a result of the deterioration of Ambac Assurance’s financial condition. As such, the following descriptions of the Financial Guarantee and Financial Services segments relate to the existing portfolios in those segments.

Through its financial services subsidiaries, Ambac provided financial and investment products, including investment agreements, funding conduits, interest rate, currency and total return swaps, principally to the clients of its financial guarantee business. Ambac Assurance insured all of the obligations of its financial services subsidiaries. As of December 31, 2009, all total return swaps were terminated and settled. The interest rate swap and investment agreement businesses are in active runoff, which is being effectuated by means of transaction terminations, settlements, restructurings and hedges, assignments and scheduled amortization of contracts.

Financial information concerning our business segments for each of 2010, 2009 and 2008 is set forth in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and the Consolidated Financial Statements and the Notes thereto, included elsewhere in this Form 10-K. Our Internet address is www.ambac.com. We make available free of charge, on or through the investor relations section of our web site, annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K, and any amendments to those reports, filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, as well as proxy statements, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the U.S. Securities and Exchange Commission. Our Investor Relations Department can be contacted at Ambac Financial Group, Inc., One State Street Plaza, New York, New York 10004, Attn: Investor Relations, telephone: 212-208-3222.

Financial Guarantee Segment

The financial guarantee segment includes financial guarantee insurance and other credit enhancement products, such as credit derivatives. Generally, financial guarantee insurance provides an unconditional and irrevocable guarantee which protects the holder of a debt obligation against non-payment when due. Pursuant to such guarantees, Ambac Assurance and its subsidiaries make payments if the obligor responsible for making payments fails to do so when scheduled. In some cases, the insured obligations permitted counterparties to assert mark-to-market termination claims; however, the assertion of any such mark-to-market claims has been enjoined by the rehabilitation court. See “2010 Overview” in Note 1 to the Consolidated Financial Statements located in Part II, Item 8 for further information.

In addition to the guarantees described above, Ambac Assurance has underwritten transactions which expose the company to risks which may not be limited to credit risk, such as market risk, natural disaster risk, mortality or other property and casualty type risk characteristics.

Ambac Assurance derives financial guarantee revenues from: (i) premiums earned from insurance contracts; (ii) net investment income; (iii) revenue from credit derivative transactions; (iv) net realized gains and losses from sales of investment securities; and (v) amendment and consent fees. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations” located in Part II, Item 7 and Note 18 of Notes to Consolidated Financial Statements located in Part II, Item 8 for further information. Prior to the discontinuance of the issuance of new financial guarantees, premiums for financial guarantees were received either upfront (typical of public finance obligations) or on an installment basis from the cash flows generated by the underlying assets (typical of structured finance obligations). Despite writing no material new business, Ambac continues to collect premiums on its existing portfolio of guarantees that pay premiums on an installment basis.

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Risk Management

The Risk Management group is primarily responsible for the development, implementation and oversight of loss mitigation strategies, surveillance and remediation of the financial guarantee portfolio (including through the pursuit of recoveries in respect of paid claims, commutations of policies and repurchases of surplus notes issued in respect of claims). These activities are integral to Ambac’s principal business strategy going forward to increase the residual value of its financial guarantee business by mitigating losses on poorly performing transactions and maximizing the return on its investment portfolio. As a consequence of the Segregated Account Rehabilitation Proceedings, the rehabilitator retains operational control and decision-making authority with respect to all matters related to the Segregated Account, including surveillance, remediation and loss mitigation. The rehabilitator operates the Segregated Account through a management services contract executed between Ambac Assurance and the Segregated Account pursuant to which the Risk Management group provides all surveillance, remediation and loss mitigation services to the Segregated Account.

Furthermore, by virtue of the contracts executed between Ambac Assurance and the Segregated Account, the rehabilitator retains the discretion to oversee and approve certain actions taken by Ambac Assurance in respect of assets and liabilities which remain in Ambac Assurance. As such, the following discussion of Ambac’s risk management practices is qualified by reference to the rehabilitator’s exercise of its discretion to alter or eliminate any of these risk management practices.

Starting in 2008, Ambac’s risk management function has evolved significantly in order to adapt to the economic crisis and its impact on the insured portfolio (the insured portfolio in this discussion refers to both Segregated Account policies and Ambac Assurance policies). The economic crisis required us to heighten our surveillance efforts on all exposures, focusing on the identification of credits and asset types across the portfolio that were likely to experience increased stress or potential for losses. Staffing in all surveillance areas has been enhanced commensurate with this intensified emphasis on the oversight of vulnerable credits. Ambac has reorganized its risk management function, with the primary focus on reducing firm-wide risk and made structural and process-related changes resulting in an organizational structure designed around major areas of focus: (1) Portfolio Risk Management and Analysis (“PRMG”); and (2) Credit Risk Management (“CRM”). The senior managers within the risk management groups report directly to the Chief Executive Officer (“CEO”) and regularly inform and update the Audit Committees of the Boards of Directors of Ambac and Ambac Assurance with respect to risk-related topics in the insured portfolio.

Portfolio Risk Management and Analysis

In portfolio risk management, the focus is on surveillance, remediation, loss mitigation and risk reduction. Risk Management personnel perform periodic surveillance reviews of exposures according to a schedule based on the risk profile of the guaranteed obligations or as necessitated by specific credit events or other macro-economic variables. The monitoring activities are designed to detect deterioration in credit quality or changes in the economic, regulatory or political environment which could adversely impact the portfolio. Active surveillance enables PRMG to track single credit migration and industry credit trends. In some cases, PRMG will engage internal or external workout experts or attorneys and other consultants with appropriate expertise in the targeted loss mitigation to assist management in examining the underlying contracts or collateral, providing industry specific advice and/or executing strategies.

Analysts review, on a regular and ad hoc basis, credits in the book of business. Risk-adjusted surveillance strategies have been developed for each bond type with review periods and scope of review based upon each bond type’s inherent risk profile. The risk profile is assessed regularly in response to our own experience and judgments or external factors such as the current market crisis. The focus of the surveillance review is to assess performance, identify credit trends and recommend appropriate credit classifications, ratings and changes to a transaction or bond type’s review period. If a problem is detected, the group focuses on loss mitigation by recommending appropriate action and working with the issuer, trustee, bond counsel, servicer and other interested parties in an attempt to remediate the problem and minimize Ambac Assurance’s exposure to potential

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loss. Those credits that are either in default or have developed problems that eventually may lead to a default, claim or loss are tracked closely by the appropriate surveillance team and discussed at regularly scheduled meetings with CRM (see discussion following on “Credit Risk Management”).

In structured transactions, including structured public finance transactions, Ambac often is the control party as a result of insuring the transaction’s senior class or tranche. The control party may direct specified parties, usually the trustee, to take or not take certain actions following contractual defaults or trigger events. Control rights and the scope of direction and remedies vary considerably among our insured transactions. Because Ambac Assurance is party to and/or has certain rights in documents supporting transactions in the insured portfolio, Ambac Assurance frequently receives requests for amendments, waivers and consents (“AWCs”). As discussed below under “Credit Risk Management”, members of Ambac Assurance’s Risk Management personnel review, analyze and process all requests for AWCs. As a part of the Segregated Account Rehabilitation Proceedings, the rehabilitation court enjoined parties to preserve Ambac’s pre-rehabilitation control rights that could otherwise have lapsed or been compromised.

Surveillance for collateral dependent transactions, including, but not limited to, residential mortgage-backed securities (“RMBS”), asset-backed securities (“ABS”), and student loan transactions, focuses on review of the underlying asset cash flows and, if applicable, the performance of servicers or collateral managers. Ambac Assurance generally receives periodic reporting of transaction performance from issuers or trustees. Analysts review these reports to monitor performance and, if necessary, seek legal or accounting advice to assure that reporting and application of cash flows comply with transaction requirements.

Proactive credit remediation can help to reduce exposure and/or reduce risk in the insured portfolio by securing rights and remedies, both of which help to mitigate losses in the event of default. The emphasis on reducing risk is centered on reducing enterprise-wide exposure on a prioritized basis.

Cross-functional teams have been established within PRMG to promote the active mitigation and/or targeted remediation of the insured portfolio. Examples of such teams include teams of professionals focused on 1) RMBS servicing surveillance and transfer, 2) the review and enforcement of contractual representations and warranties in RMBS policies and 3) the analysis, restructuring and commutation of Segregated Account policies. The establishment and purview of cross-functional teams is targeted to address our highest risk exposures. Members of such teams work with both internal and external experts in the pursuit of risk reduction on all fronts.

The RMBS servicing surveillance team focuses on servicer oversight and remediation, with an immediate focus on active remediation of servicing in the mortgage-backed sector. Analysts monitor the performance of transaction servicers through a combination of (i) regular servicer reviews; (ii) compliance certificates received from servicer management; (iii) independent rating agency information; and (iv) a review of servicer financial information. Servicer reviews typically include a review of the collection, default management and quality control processes. In addition, Ambac Assurance may require a back-up servicer or require “term-to-term” servicing which provides for limited, renewable servicing terms in order to provide greater flexibility regarding the servicing arrangements of a particular transaction.

In some transactions Ambac Assurance has the right to direct a transfer of servicing to an alternative servicer, subject to certain conditions. The decision to exercise this right is made based on various factors, including an assessment of the performance of the existing servicer as outlined above, and an assessment of whether a transfer of servicing may improve the performance of the collateral. Ambac Assurance assesses potential transferee servicers through on-site servicer reviews and reviews of servicer financial information. Accordingly, Ambac Assurance has developed relationships with preferred servicers in the residential mortgage backed-sector. Preferred servicers are selected via a formalized servicer review process that determines, among other key factors, the servicer’s ability and willingness to actively manage intense and proven loss mitigation activities on RMBS. On selected distressed or high risk RMBS, Ambac Assurance may decide to exercise its rights to direct the transfer of servicing to a preferred servicer. The transfer of servicing is done with the

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objectives of (i) minimizing deal losses and distress levels by deploying targeted and enhanced loss mitigation programs; (ii) increasing visibility to Ambac Assurance of all servicing activities that impact overall deal performance; and (iii) better aligning the servicer’s financial interest to the performance of the underlying deal through the utilization of performance based incentives. Ambac Assurance believes that the improved loss mitigation activities, alignment of interests and close monitoring of the preferred servicers constitute credible means of minimizing risks and losses related to selected Ambac Assurance insured RMBS.

A team of professionals has also been established to focus on recoveries from sponsors where Ambac Assurance believes that a material breach of representations and warranties has occurred with respect to certain RMBS policies. The team monitors monthly performance of the RMBS insured portfolio and uses criteria to determine which transactions to pursue with regard to such recoveries. The team engages experienced consultants to perform the re-underwriting of loan files and consult with internal and external legal counsel with regard to loan putbacks as well as settlement and litigation strategies (see Management’s Discussion and Analysis of Financial Condition and Results of Operations – Representation and Warranty Breaches by RMBS Transaction Sponsors for further discussion on this topic).

The cross-functional restructuring team focuses on the analysis and prioritization of policies in the Segregated Account to target and execute risk reduction and commutation strategies. Analysis provided by this team may include assistance and guidance in model development and modeling, market, credit and data analysis and document review.

Credit Risk Management

CRM manages the decision process for all material matters that affect credit exposures within the insured portfolio. The scope of credit matters under the purview of CRM includes amendments, waivers and consents, remediation plans, credit review scheduling, adverse credit classification and below investment grade rating designations, adversely classified credit reviews, sector reviews, and overall portfolio review scheduling. The decision process may involve a review of structural, legal, political and credit issues and also includes determining the proper level of approval, which varies based on the nature and materiality of the matter.

Adversely Classified Credit Review

Credits that are either in default or have developed problems that eventually may lead to a default, claim or loss are tracked closely by the appropriate surveillance team and discussed at meetings with CRM. Adversely classified credit meetings include members of CRM and appropriate senior management, surveillance and legal analysts, as necessary. A summary of the adversely classified credits and trends is also provided to Ambac’s and Ambac Assurance’s Boards of Directors on a quarterly basis. As part of the review, relevant information, along with the plan for corrective actions and a reassessment of the credit’s rating and credit classification is considered. Internal and/or external counsel generally reviews the documents underlying any problem credit and, if applicable, an analysis is prepared outlining Ambac Assurance’s rights and potential remedies, the duties of all parties involved and recommendations for corrective actions. Ambac Assurance also meets with relevant parties to the transaction as necessary. The review schedule for adversely classified credits is tailored to the remediation plan to track and prompt timely action and proper internal and external resourcing.

Amendment, Waiver and Consent Review / Approval

The decision to approve or reject AWCs on an issue is based upon certain credit factors, such as the issuer’s ability to repay the bonds and the bond’s security features and structure. Members of Ambac Assurance’s Risk Management group review, analyze and process all requests for AWCs. All AWCs are initially screened for materiality in the surveillance groups. Material AWCs are within the purview of CRM, as discussed above. Non-material AWCs require the approval of at least a surveillance analyst and a portfolio risk manager. For material AWCs, CRM has established minimum requirements that may be modified to require more or varied signatures depending upon the matter’s complexity, size or other characteristics.

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Ambac Assurance assigns internal ratings to individual exposures as part of the AWC process and at surveillance reviews. These internal ratings, which represent Ambac Assurance’s independent judgments, are based upon underlying credit parameters consistent with the exposure type.

Included in the above net par exposures at December 31, 2010 are $18,766 of exposures underwritten under credit derivative execution, primarily CDO exposures. See Part II, Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations” for further discussion of CDO exposures. Please also refer to “2010 Overview” located in Note 1 to the Consolidated Financial Statements in Item 8 of this Form 10-K for a description of the Settlement Agreement with respect to CDO of ABS and certain other CDO-related obligations.

Financial guarantee products were sold in three principal markets: the U.S. public finance market, the U.S. structured finance and asset-backed market and the international finance market.

U. S. Public Finance Insured Portfolio

Ambac’s portfolio of U.S. Public Finance exposures is $199 billion, representing 63% of Ambac’s net par outstanding as of December 31, 2010. U.S. Public Finance consists of U.S. municipal issuances, including general obligations, lease and tax-backed obligations, health care, housing, public utilities, transportation and higher education, as well as certain infrastructure privatization transactions, such as toll road and bridge financings, public transportation financings, stadium financings, military housing and student housing. Public finance obligations are generally supported by either the taxing authority of the issuer or the issuer’s or underlying obligor’s ability to collect fees or assessments for certain projects or public services. See Note 15 to the Consolidated Financial Statements, located in Part II, Item 8 of this Form 10-K for exposures by bond type as of December 31, 2010.

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The table below shows our ten largest Public Finance exposures, by repayment source, as a percentage of total Financial Guarantee net par outstanding at December 31, 2010:

U.S. Structured Finance and Asset-Backed Insured Portfolio

Ambac’s portfolio of U.S. Structured Finance exposures is $74 billion, representing 23% of Ambac’s net par outstanding as of December 31, 2010. Insured exposures include securitizations of mortgage loans, home equity loans, auto loans, student loans, leases, operating assets, CDOs and other asset-backed financings, in each case where the majority of the underlying collateral risks is situated in the United States. Additionally, Ambac’s Structured Finance insured portfolio encompasses both secured and unsecured debt issued by investor-owned utilities. Included within the operating asset sector are securitizations of aircraft, rental cars, shipping container and rail car fleets, franchise fees, pharmaceutical royalties, and intellectual property. See Note 15 to the Consolidated Financial Statements, located in Part II, Item 8 in this Form 10-K for exposures by bond type as of December 31, 2010.

Structured finance exposures generally entail three forms of risks: (i) asset risk, which relates to the amount and quality of the underlying assets; (ii) structural risk, which relates to the extent to which the transaction’s legal structure and credit support provide protection from loss; and (iii) servicer risk, which is the risk that poor performance at the servicer or manager level contributes to a decline in cash flow available to the transaction. Ambac Assurance seeks to mitigate and manage these risks through its Risk Management practices.

Structured securities are usually designed to help protect the investors and, therefore, the guarantor from the bankruptcy or insolvency of the entity that originated the underlying assets as well as from the bankruptcy or insolvency of the servicer of those assets. The servicer of the assets is typically responsible for collecting cash payments on the underlying assets and forwarding such payments, net of servicing fees, to a trustee for the benefit of the issuer. One potential issue is whether the sale of the assets by the originator to the issuer would be upheld in the event of the bankruptcy or insolvency of the originator and whether the servicer of the assets may be permitted or stayed from remitting to investors cash collections held by it or received by it after the servicer or

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the originator becomes subject to bankruptcy or insolvency proceedings. Another potential issue is whether the originator sold ineligible assets to the securitization transaction that subsequently deteriorated, and, if so, whether the originator has the willingness or financial wherewithal to meet its contractual obligations to repurchase those assets out of the transaction. Structural features of a transaction, such as control rights that are typically held by the senior note holders, or guarantor in insured transactions, will impact the extent to which underlying asset performance affects the performance of the securities.

The following table presents the top five servicers by net par outstanding, for global structured finance exposures:

Structured Finance includes the credit enhancement of CDOs and CLOs. These transactions involve the securitization of a portfolio of corporate bonds, corporate loan obligations and/or asset-backed securities. In June 2010, all CDO of ABS transactions, which included substantial exposure to residential mortgages, were settled. Please refer to “U. S. Residential Mortgage-Backed Securities Exposures” below for further discussion. Please also refer to “2010 Overview” located in Note 1 to the Consolidated Financial Statements in Item 8 of this Form 10-K for a description of the Settlement Agreement with respect to CDO of ABS and certain other CDO-related obligations.

The table below shows our ten largest Structured Finance transactions, as a percentage of total financial guarantee net par outstanding at December 31, 2010:

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International Finance Insured Portfolio

Ambac’s portfolio of International Finance insured exposures is $46 billion, representing 14% of Ambac’s net par outstanding as of December 31, 2010. Ambac’s existing International Finance insured exposures include a wide array of obligations in the international markets, including infrastructure financings, asset-securitizations, CDOs, utility obligations, and whole business securitizations (e.g. securitizations of substantially all of the operating assets of a corporation). In emerging markets, Ambac had focused on future cash flow transactions from top tier issuers (structured transactions secured by U.S. Dollar and Euro cash flows generated from exports or payment remittances) and, to a more limited extent, on domestic securitizations. See Note 15 to the Consolidated Financial Statements, located in Part II, Item 8 in this Form 10-K for exposures by bond type as of December 31, 2010.

When underwriting transactions in the international markets, Ambac considered the specific risks related to the particular country and region that could impact the credit of the issuer. These risks include the legal and political environment, capital market dynamics, foreign exchange issues, and the degree of governmental support. Ambac continues to address these risks through its ongoing credit risk management.

Ambac UK, which is regulated in the United Kingdom, had been Ambac Assurance’s primary vehicle for directly issuing financial guarantee policies in the United Kingdom and the European Union with $27 billion of par outstanding at December 31, 2010. Geographically, Ambac UK’s exposures are principally in the United Kingdom, continental Europe, Australia and Japan. In 2009, Ambac UK’s license to issue new business was curtailed by the United Kingdom Financial Services Authority, Ambac UK’s regulator (the “FSA”). Following the AUK Commutation Agreement as discussed in the “2010 Overview” located in Note 1 to the Consolidated Financial Statements in Item 8 of this Form 10-K, there is no portfolio risk transfer from Ambac UK to Ambac Assurance, nor does Ambac Assurance have any capital support obligation of Ambac UK. The portfolio of insured exposures underwritten by Ambac UK is now financially supported entirely by Ambac UK on a standalone basis.

The table below shows our largest International Finance transactions as a percentage of total financial guarantee net par outstanding at December 31, 2010:

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Additional Insured Portfolio Statistics:

Ambac Assurance underwrote and priced financial guarantees based on the assumption that the guarantees would remain in force until the expected maturity of the underlying bonds. Ambac Assurance estimates that the average life of its guarantees on par in force at December 31, 2010 is approximately 13 years. The 13 year average life is determined by applying a weighted average calculation, using the remaining years to expected maturity of each guaranteed bond, and weighting them on the basis of the remaining net par guaranteed. No assumptions are made for future refundings of guaranteed issues.

U.S. Residential Mortgage-backed securities exposure

RMBS portfolio exposures included in financial guarantee insurance portfolio

Ambac has exposure to the U.S. mortgage market through direct financial guarantees of RMBS. Ambac insures tranches issued in RMBS, including transactions that contain risks to first and second-liens. The following tables provide current gross par outstanding by vintage and type, and underlying credit rating of Ambac’s affected U.S. RMBS book of business:

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RMBS exposure in collateralized debt obligations

Ambac’s outstanding CDO exposures are comprised of the following asset type and credit ratings as of December 31, 2010 and December 31, 2009:

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Auction Rate Securities and Variable Rate Demand Obligations:

Fixed income securities issued in the US bond market include fixed and variable rate bonds. Included within the variable rate bond category are Auction Rate Securities (“ARS”) and Variable Rate Demand Obligations (“VRDO”). The following table sets forth Ambac Assurance’s financial guarantee net par exposure outstanding, by bond type, relating to such variable rate securities at December 31, 2010 and December 31, 2009:

ARS are sold through a Dutch auction, which is a competitive bidding process used to determine rates on each auction date. Bids are submitted to the auction agent. The winning bid rate is the rate at which the auction “clears”, meaning the lowest possible interest rate that results in the cumulative total of securities demanded at such rate (“buyers”) equaling the amount auctioned (“sellers”). VRDO are long-term bonds that bear a floating interest rate and that provide investors the option to tender or put securities back to the issuer at any time with appropriate notice. Additionally, there are certain mandatory events that require all bondholders to tender their VRDO to the issuer. Upon tender, bondholders are paid a purchase price, equal to the par amount of the tendered VRDO plus accrued interest, typically paid from the proceeds of a remarketing of the tendered VRDO by a remarketing agent. The interest rate resets daily or weekly, depending upon the security. The reset rate is based on comparable securities with similar maturities and credit ratings, as well as on supply and demand.

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VRDO are typically supported by a liquidity facility in the form of a standby bond purchase agreement (“Standby Bond Purchase Agreement”), usually provided by a commercial bank (“Liquidity Provider”). If the remarketing agent is unable to remarket all tendered VRDO, the Liquidity Provider is required to purchase such VRDO at the purchase price, subject to limited conditions precedent, thus providing liquidity to investors. While held by the Liquidity Provider, the VRDO bear interest at a rate determined under the Standby Bond Purchase Agreement, often based on the Prime Rate or LIBOR plus a spread (the “Bank Rate”). During such time, the remarketing agent remains obligated to continue to try to remarket the VRDO held by the Liquidity Provider. Many Standby Bond Purchase Agreements provide that, after the Liquidity Provider has held the VRDO for a specified time period, the issuer or other obligor is required to cause such VRDO to be redeemed prior to maturity, either: in periodic installments over a predetermined number of years, typically from three to five (the “Term-Out”); or with available funds as defined in the transaction documents; or in a single lump sum at the end of three to five years. Other Standby Bond Purchase Agreements do not contain a Term-Out. For VRDO insured by Ambac Assurance, Ambac Assurance has typically endorsed its insurance policy to cover interest at the Bank Rate. For VRDOs insured by Ambac Assurance that contain a Term-Out, Ambac has often endorsed its insurance policy to cover the required redemptions in accordance with the Term-Out schedule (though not any acceleration of the VRDO maturity ahead of the Term-Out schedule).

For student loan VRDO transactions, Ambac Assurance is required to purchase any outstanding VRDO from the Liquidity Providers at the end of the Term-Out period for the par amount of the bonds. All student loan VRDO transactions insured by Ambac Assurance have been purchased by the Liquidity Providers and, as such, Ambac Assurance has obligations to purchase, at par, outstanding VRDOs at par coming due in 2013, 2015 and 2018 in the amounts of $493.0 million, $68.3 million, and $175.1 million, respectively. Ambac Assurance’s purchase obligation in 2013, 2015 and 2018 will depend on many factors, including the successful execution of loss mitigation strategies, changes in interest rates, performance of the underlying collateral, the deterioration of the asset base and/or any amortization of the VRDO.

Issuers have been working toward reducing their debt service costs for ARS and VRDO transactions; the most prevalent ways are (i) converting the bonds to fixed rate (to maturity or for a shorter period of time); (ii) refunding the obligations and issuing bonds or other debt structures; (iii) purchasing direct-pay letters of credit from other financial institutions; or (iv) amending their liquidity facilities to address investor liquidity concerns.

For Ambac Assurance insured ARS and VRDO transactions that have been unable to refinance, the higher debt service costs have resulted in decreased debt service ratios and/or the erosion of first loss and/or other credit enhancements that are subordinate to Ambac Assurance’s risk position (such as excess spread). Through December 31, 2010, Ambac Assurance paid gross claims in the amount of $61 million on these transactions. This included approximately $13 million for certain student loan ARS transactions that were restructured in 2010, which resulted in the elimination of certain ARS policies. Ambac has established gross loss reserves of approximately $688 million for ARS and VRDO transactions, which is net of expected recoveries. Ambac continues to actively review the credit implications of this additional issuer stress and its impact to our internal credit ratings and loss reserves as necessary.

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Issue Size

Ambac Assurance’s financial guarantee exposure in the U.S. public finance market reflects the historical emphasis on issues guaranteed with an original par amount of less than $50 million. U.S. Structured Finance and International Finance transactions generally involved larger transaction sizes. The following table sets forth the distribution of Ambac Assurance’s guaranteed portfolio as of December 31, 2010 with respect to the original size of each guaranteed issue:

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Mortgage and asset-backed obligations includes guarantees with multiple locations of risk within the United States and is primarily comprised of residential mortgage and asset-backed securitizations. Internationally diversified is primarily made up of CDOs which include significant components of U.S. exposure.

Ratings Distribution

The following tables provide a rating distribution of guaranteed total net par outstanding based upon internal Ambac Assurance credit ratings at December 31, 2010 and December 31, 2009 and a distribution by bond type of Ambac Assurance’s below investment grade exposures at December 31, 2010 and December 31, 2009. Below investment grade is defined as those exposures with a credit rating below BBB-:

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The decrease in CDO of ABS greater than 25% RMBS resulted from execution of the Settlement Agreement in June 2010. Refer to “2010 Overview” in Note 1 to the Consolidated Financial Statements located in Part II, Item 8 for a description of the Settlement Agreement with respect to CDO of ABS and certain other CDO-related obligations. The decrease in mortgage-backed and home equity (first and second-liens) below investment grade exposures is primarily the result of principal pay-downs. The increase in student loan below investment grade exposures was due to deterioration in private student loan collateral performance and the failed debt structures for the ARS & VRDO exposures which exposes these transactions to interest rate risk. The decrease on other structured finance obligations is primarily related to the commutation of a film-securitization transaction. The increase in Public Finance is primarily related to deterioration of certain military housing and tax backed transactions.

Commitments to Issue Future Guarantees

In connection with its financial guarantee business, Ambac has outstanding commitments to provide guarantees (consisting of both insurance and credit derivatives) of $5.9 billion at December 31, 2010. These commitments relate to potential future debt issuances or increases in funding levels for existing insurance or credit derivative transactions. Commitments generally have fixed termination dates and are contingent on the satisfaction of all conditions set forth in the contract. These commitments may expire unused or be reduced or cancelled at the counterparty’s request. Additionally, approximately 80% of the total commitment amount represents commitments that contain one or more of the following provisions: (i) the commitment may be terminated at Ambac’s election upon a material adverse change, (ii) in order for the funding levels to be

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increased, certain eligibility requirements must be met, or, (iii) for commitments to provide protection, the commitment may not be exercised upon an event of default or after the reinvestment period. Moreover, as a consequence of the Segregated Account Rehabilitation Proceedings and the terms of the Settlement Agreement, it is unclear whether such new policies could be issued. Accordingly, the $5.9 billion of commitments outstanding at December 31, 2010 do not necessarily reflect actual future obligations. Additionally, due to Ambac Assurance’s current financial position, most commitments are unlikely to be exercised.

As a primary financial guarantor, Ambac Assurance is required to honor its obligations to its policyholders whether or not its reinsurers perform their obligations under the various reinsurance agreements. To minimize its exposure to significant losses from reinsurer insolvencies, Ambac Assurance is entitled to receive collateral from its reinsurance counterparties in certain reinsurance contracts and has certain cancellation rights that can be

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exercised by Ambac Assurance in the event of rating agency downgrades of a reinsurer. At the inception of each reinsurance contract, Ambac Assurance required collateral from certain reinsurers primarily to (i) receive statutory credit for the reinsurance to foreign reinsurers, (ii) provide liquidity to Ambac Assurance in the event of claims on the reinsured exposures, and (iii) enhance rating agency credit for the reinsurance. When a reinsurer is downgraded by one or more rating agencies, less capital credit is given to Ambac Assurance under rating agency models. Ambac Assurance held letters of credit and collateral amounting to approximately $312.9 million from its reinsurers at December 31, 2010. Refer to Item 7A – Risk Management for further discussion on insured par ceded, credit ratings of our reinsurance counterparties and unsecured reinsurance balances.

Assumed Reinsurance:

The majority of Ambac Assurance’s assumed reinsurance contracts were cancelled in 2009. At December 31, 2010, the remaining assumed par outstanding was $439.5 million. On March 24, 2010, all assumed reinsurance agreements with third parties were allocated to the Segregated Account, which will not allow for further cancellations without the approval of the Rehabilitator.

Rating Agencies

Ambac Assurance’s financial strength ratings have been downgraded several times since 2008; it now has a Caa2 financial strength rating with a developing outlook from Moody’s. Moody’s rating refers to Ambac Assurance general account obligations and excludes obligations allocated to the segregated account.

In 2010 Ambac Assurance requested that S&P withdraw its ratings. Ambac Assurance’s request was predicated by a review of the value of such rating relative to the cost. Ambac continues to evaluate the relative merits of maintaining a Moody’s rating and may decide to similarly request a withdrawal of such rating.

Insurance Regulatory Matters

Ambac Assurance and Everspan are domiciled in the State of Wisconsin and, as such, are subject to the insurance laws and regulations of the State of Wisconsin (the “Wisconsin Insurance Laws”) and are regulated by the OCI. In addition, Ambac Assurance and Everspan are subject to the insurance laws and regulations of the other jurisdictions in which they are licensed. Ambac Assurance is licensed in all other 49 states, the District of Columbia, the Commonwealth of Puerto Rico, the territory of Guam and the U.S. Virgin Islands and Everspan is licensed in all states other than Virginia, the District of Columbia and the Commonwealth of Puerto Rico. Under Wisconsin insurance law, the Segregated Account is a separate insurer for purposes of the Segregated Account Rehabilitation Proceedings. As such, the Segregated Account is not separately licensed or regulated, but it is under the control of, and is overseen by, the Rehabilitator.

Insurance laws and regulations applicable to financial guarantee insurers vary by jurisdiction. The laws and regulations generally require financial guarantors to maintain minimum standards of business conduct and solvency; to meet certain financial tests; and to file policy forms, premium rate schedules and certain reports with regulatory authorities, including information concerning capital structure, ownership and financial condition. Regulated insurance companies are also required to file quarterly and annual statutory financial statements with the National Association of Insurance Commissioners (“NAIC”), and in each jurisdiction in which they are licensed. The level of supervisory authority that may be exercised by non-domiciliary insurance regulators varies by jurisdiction. Generally, however, non-domiciliary regulators are authorized to revoke insurance licenses and to impose license restrictions in the event that laws or regulations are breached by a regulated insurance company or in the event that continued or unrestricted licensure of the regulated insurance company constitutes a “hazardous condition” in the opinion of the regulator. Ambac Assurance’s authority to write new business in Alabama, Louisiana, North Dakota, Tennessee and Ohio has been suspended.

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Wisconsin Insurance Laws require regulated insurance companies to maintain minimum standards of business conduct, minimum surplus to policyholders and solvency. As the principal, or domiciliary, regulator of Ambac Assurance and Everspan, OCI has primary regulatory authority, including with respect to the initiation and administration of rehabilitation or liquidation proceedings with respect to Ambac Assurance and Everspan. Additionally, the accounts and operations of Ambac Assurance and Everspan are subject to a comprehensive examination by the OCI every three to five years. As described in “2010 Overview” located in Note 1 to the Consolidated Financial Statements in Item 8 of this Form 10-K, the rehabilitator of the Segregated Account has imposed certain constraints upon Ambac Assurance through the covenants made for the benefit of the Segregated Account and has assumed the authority to control the management of the Segregated Account.

During the course of 2009, Ambac UK’s license to do new business was curtailed by the FSA, and the insurance license was limited to undertaking only run-off related activity. As such, Ambac UK is authorized to run-off its credit, suretyship and financial guarantee insurance portfolio in the United Kingdom, and to do the same through a branch in Milan, Italy, and a number of other European Union (“EU”) countries. EU legislation has allowed Ambac UK to conduct business in EU states other than the United Kingdom through a “passporting” arrangement, which eliminates the necessity of additional licensing or authorization in those other EU jurisdictions.

Ambac UK remains subject to regulation by the FSA in the conduct of its business. The FSA is the single statutory regulator responsible for regulating the financial services industry in the United Kingdom, with the purpose of maintaining confidence in the U.K. financial system, providing public understanding of the system, securing the proper degree of protection for consumers and helping to reduce financial crime. In addition, the regulatory regime in the United Kingdom must comply with certain EU legislation binding on all EU member states. Notwithstanding the aforementioned, the regulatory structure of the United Kingdom is currently undergoing restructuring, whereby regulatory responsibility will be divided between The Bank of England and a reconstituted FSA. The precise impact on Ambac UK is as yet unclear however no material impact is anticipated with respect to Ambac UK being closely supervised as a run-off entity.

The FSA has exercised significant oversight of Ambac UK since 2008, when Ambac Financial Group, and Ambac Assurance (Ambac UK’s only reinsurer and principal financial support provider prior to the AUK Commutation Agreement) began experiencing financial stress. As more fully discussed in “2010 Overview” in Note 1 to the Consolidated Financial Statements located in Part II, Item 8 in this Form 10-K, Ambac Assurance entered into the AUK Commutation Agreement with Ambac UK and the Special Deputy Commissioner of OCI, on September 28, 2010, pursuant to which the AUK Reinsurance Agreement was commuted and the Net Worth Maintenance Agreement between Ambac UK and Ambac Assurance was terminated in exchange for, among other things, certain mutual releases, including, without limitation, any right of Ambac Assurance or the Segregated Account to reinsurance premiums from Ambac UK. Ambac Assurance paid a nominal termination amount of one U.S. dollar to Ambac UK in connection with the commutation.

The FSA requires that non-life insurance companies such as Ambac UK maintain a margin of solvency at all times in respect of the liabilities of the insurance company, the calculation of which depends on the type and amount of insurance business a company writes. In addition, the FSA had established a capital monitoring level for Ambac UK related to its insured portfolio. Breach of the monitoring level required that Ambac UK inform the FSA and enter into discussions as to the reasons for the breach, and ultimately with a view to a remedy that could include additional capital being required. The monitoring level is normally an interim arrangement, while the FSA reflects on alternative methodologies for a permanent basis for calculating regulatory capital in respect of Ambac UK and other financial guarantors regulated by the FSA. In addition, an insurer is required to perform and submit to the FSA a solvency margin calculation return in respect of its ultimate parent. All of these solvency requirements may be amended in order to implement the European Union’s proposed “Solvency II” directive on risk-based capital, but that is not expected to be implemented until 2012 at the earliest. The impact of such proposals on Ambac UK remains unclear.

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Notwithstanding the foregoing, following the Ambac UK Commutation Agreement, Ambac UK is deficient in terms of compliance with applicable regulatory capital requirements. The FSA is aware of the same, and dialogue between Ambac UK management and the FSA remains ongoing with respect to options for addressing the shortcoming, although such options remain few.

Under Wisconsin law applicable to insurance holding companies, any acquisition of control of Ambac, and any other direct or indirect control of Ambac Assurance and Everspan, requires the prior approval of the OCI. “Control” is defined as the direct or indirect power to direct or cause the direction of the management and policies of a person. Any purchaser of 10% or more of the outstanding voting stock of a corporation is presumed to have acquired control of that corporation and its subsidiaries unless the OCI, upon application, determines otherwise. For purposes of this test, Ambac believes that a holder of common stock having the right to cast 10% of the votes which may be cast by the holders of all shares of common stock of Ambac would be deemed to have control of Ambac Assurance and Everspan within the meaning of the Wisconsin Insurance Laws. The United Kingdom has similar requirements applicable in respect of Ambac, as the ultimate holding company of Ambac UK.

At various times, investors have sought and obtained OCI’s approval to acquire greater than 10% of Ambac’s outstanding stock. As a condition to obtaining approval without undergoing a comprehensive “change of control” review process, those investors disclaimed any present intention to exercise control over Ambac, Ambac Assurance or Everspan or to control or attempt to control the management or operations of Ambac, Ambac Assurance or Everspan.

Dividend Restrictions, Including Contractual Restrictions

Pursuant to the Wisconsin Insurance Laws, Ambac Assurance and Everspan may declare dividends, subject to restrictions in their respective articles of incorporation, provided that, after giving effect to the distribution, such dividends would not violate certain statutory equity, solvency, income and asset tests. Shareholder distributions by Ambac Assurance and Everspan (other than stock dividends) must be reported to the OCI. Additionally, no quarterly dividend may exceed the dividend paid in the corresponding quarter of the preceding year by more than 15% without notifying the OCI 30 days in advance of payment. Extraordinary dividends must be reported prior to payment and are subject to disapproval by the OCI. An extraordinary dividend is defined as a dividend or distribution, the fair market value of which, together with all dividends from the preceding 12 months, exceeds the lesser of: (a) 10% of policyholders’ surplus as of the preceding December 31 or (b) the greater of: (i) statutory net income for the calendar year preceding the date of the dividend or distribution, minus realized capital gains for that calendar year; or (ii) the aggregate of statutory net income for the three calendar years preceding the date of the dividend or distribution, minus realized capital gains for those calendar years and minus dividends paid or credited and distributions made within the first two of the preceding three calendar years. Additionally, in connection with the termination of reinsurance contracts, OCI requires adjustments to the dividend calculations for any surplus or net income gains recognized. Due to losses experienced by Ambac Assurance in 2009 and 2010, Ambac Assurance was unable to pay common dividends to Ambac in 2009 and 2010 and will be unable to pay common dividends in 2011, without the prior consent of the OCI.

During 2008, Ambac Assurance paid to Ambac cash dividends on its common stock totaling $218.5 million, respectively. See Note 17 to the Consolidated Financial Statements located in Part II, Item 8 for further information on dividends. During 2010 and 2009, Ambac Assurance paid cash dividends on its preferred shares of $0.8 million and $12.5 million, respectively.

Ambac Assurance’s ability to pay dividends is further restricted by certain covenants made for the benefit of the Segregated Account and by the Settlement Agreement. See “2010 Overview” in Note 1 to the Consolidated Financial Statements located in Part II, Item 8 for further information.

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UK law prohibits Ambac UK from declaring a dividend to its shareholders unless it has “profits available for distribution.” The determination of whether a company has profits available for distribution is based on its accumulated realized profits less its accumulated realized losses. While the UK insurance regulatory laws impose no statutory restrictions on a general insurer’s ability to declare a dividend, the FSA’s capital requirements may in practice act as a restriction on the payment of dividends. Further, the FSA has amended Ambac UK’s license such that the FSA must specifically approve (“non-objection”) to any transfer of value and/or assets from Ambac UK to Ambac Assurance or any other Ambac group company, other than in respect of certain disclosed contracts between the two parties (such as in respect of a management services agreement between Ambac Assurance and Ambac UK). Ambac UK is not expected to pay any dividends to Ambac Assurance for the foreseeable future.

Pursuant to the Settlement Agreement, as discussed in the “2010 Overview” in Note 1 to the Consolidated Financial Statements located in Part II, Item 8, Ambac Assurance may not make any Restricted Payment (which includes dividends from Ambac Assurance to Ambac) in excess of $5 million in the aggregate, other than Restricted Payments from Ambac Assurance to Ambac in an amount (i) up to $52 million per annum solely to pay interest on indebtedness of Ambac outstanding as of March 15, 2010, or any indebtedness issued as a result of a restructuring or refinancing thereof and (ii) up to $7.5 million per annum solely to pay operating expenses of Ambac. Concurrent with making any such Restricted Payment, a pro rata amount of the Surplus Notes issued by Ambac Assurance to the bank group would also need to be redeemed at par.

Under the terms of Ambac Assurance’s Auction Market Preferred Shares (“AMPS”), dividends may not be paid on the common stock of Ambac Assurance unless all accrued and unpaid dividends on the AMPS for the then current dividend period have been paid, provided, that dividends on the common stock may be made at all times for the purpose of, and only in such amounts as are necessary for, enabling Ambac (i) to service its indebtedness for borrowed money as such payments become due or (ii) to pay its operating expenses. If dividends are paid on the common stock as provided in the prior sentence, dividends on the AMPS become cumulative until the date that all accumulated and unpaid dividends have been paid on the AMPS.

New York Financial Guarantee Insurance Law and Financial Guarantee Insurance Regulation in Other States

New York’s comprehensive financial guarantee insurance law defines the scope of permitted financial guarantee insurance and governs the conduct of business of all financial guarantors licensed to do business in New York, including Ambac Assurance. The New York financial guarantee insurance law also establishes single risk and aggregate limits with respect to insured obligations insured by financial guarantee insurers. Such single risk limits are specific to the type of insured obligation (for example, municipal or asset-backed). Under the aggregate limits, policyholders’ surplus and contingency reserves must at least equal a percentage of aggregate net liability that is equal to the sum of various percentages of aggregate net liability for various categories of specified obligations. Wisconsin laws and regulations applicable to financial guarantors, as well as the laws of several other states, are less comprehensive than New York law and relate primarily to single and aggregate risk limits.

As a result of decreased statutory capital resulting from the significant losses experienced by Ambac Assurance, Ambac Assurance is not in compliance with the single and aggregate risk limits. Through run-off of the portfolio, Ambac Assurance will seek to reduce its exposure to no more than the permitted amounts, but may not be able to due so. Everspan is in compliance with all of such limits.

Financial Services Segment

Ambac’s Financial Services segment historically provided financial and investment products, including investment agreements, derivative products (interest rate, currency and total return swaps) and funding conduits, principally to clients of the financial guarantee business. In 2008, Ambac discontinued writing new investment agreements and derivative products. Its existing investment agreement and derivative product portfolios are in

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active runoff, which in addition to natural attrition, may include transaction terminations, settlements, restructuring and hedging, and transfers. As of December 31, 2009 all total return swaps were terminated and settled.

The principal factors that may affect results as the Financial Services portfolios runoff include: (1) availability of counterparties for hedging transactions; (2) investment returns; (3) the transaction value of future contract terminations, settlements or transfers which may differ from carrying value of the those assets; (4) changes in the value of securities posted as collateral; (5) the ability to obtain additional liquidity support from Ambac Assurance if needed; (6) changes in the fair value of the derivatives portfolio resulting from interest rate index fluctuations and (7) the restrictions imposed upon Ambac Assurance by the contracts executed with the Segregated Account, the restrictions imposed upon Ambac Assurance by the Settlement Agreement, and, to the extent that Segregated Account Policies are implicated, the authority of the rehabilitator of the Segregated Account to control the management of the Segregated Account.

Investment Agreements

Ambac provided investment agreements, including repurchase agreements, primarily to issuers of asset-backed and structured finance debt and, to a lesser extent, to municipal issuers through its wholly-owned subsidiary, Ambac Capital Funding. Investment agreements used in structured financings provide a guaranteed investment return customized to meet expected and potential cash flow requirements. Investment agreements are used by bond issuers to invest bond proceeds until such proceeds can be used for their intended purpose, such as financing construction. The investment agreement provides for the guaranteed return of principal invested, as well as the payment of interest thereon at a guaranteed rate.

Liquidity risk exists in the portfolio due to contract provisions which require collateral posting or allow early termination of contracts. During 2010, reductions to the balance of outstanding investment agreements resulting from required or negotiated early terminations totaled $0.3 billion. As of December 31, 2010, 98% of investment agreement principal and accrued interest outstanding was collateralized. Funding for early terminations was supported in part through loans between Ambac Capital Funding and Ambac Assurance. At December 31, 2010, Ambac Capital Funding was indebted to Ambac Assurance in the amount of $553 million in cash loans.

See “Liquidity and Capital Resources” of the Management Discussion and Analysis of Financial Condition and Results of Operations” located in Part II, Item 7 and Note 8 to the Consolidated Financial Statements located in Part II, Item 8 for further information on investment agreements.

Derivative Products

The primary activities in the derivative products business were intermediation of interest rate and currency swap transactions (through Ambac Financial Services (“AFS”)) and taking total return swap positions on certain fixed income obligations (through Ambac Capital Services). Certain municipal interest rate swaps are not hedged for the basis difference between issue specific and general tax-exempt index rates. The derivative portfolio also includes an unhedged Sterling-denominated exposure to consumer price inflation in the United Kingdom. In addition, the derivative products business also uses exchange traded U.S. Treasury futures contracts to hedge interest rate exposures. Therefore, changes in the relationship between taxable and tax-exempt index and municipal issue specific rates, as well as between taxable index and Treasury interest rates may result in gains or losses on interest rate swaps. Additionally, beginning in 2009, the derivative products portfolio retained positive mark-to-market sensitivity to interest rate increases to mitigate floating rate obligations in the Financial Guarantee segment, including in the credit derivative portfolio.

Interest rate and currency swaps used for hedging purposes are generally subject to master agreements. These agreements generally require a counterparty in a net mark-to-market liability position to post increasing amounts of collateral if that counterparty’s credit rating declines and/or the net mark-to-market liability

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increases. Some contracts also contain additional termination provisions linked to downgrades of Ambac Assurance, as guarantor of the swaps. As a result of ratings downgrades to Ambac Assurance in 2008 and 2009, AFS lost its collateral posting thresholds and experienced termination events across all its professional counterparties. Such termination events have resulted in losses to AFS due to the higher cost of replacing hedge positions, and may result in additional losses in future periods. Beginning in 2008, AFS borrowed from Ambac Assurance, to help support the incremental collateral posting requirements and termination payments resulting from the Ambac Assurance downgrades. At December 31, 2010, AFS was indebted to Ambac Assurance in the amounts of $385 million in cash loans and $175 million in borrowed securities.

AFS manages a variety of risks inherent in its businesses, including credit, market, liquidity, operational and legal. These risks are identified, measured, and monitored through a variety of control mechanisms, which are in place at different levels throughout the organization. See “Quantitative and Qualitative Disclosures About Market Risk” located in Part II, Item 7A for further information.

Funding Conduits

Ambac previously transferred financial assets to two special purpose entities. The business purpose of these entities was to provide certain financial guarantee clients with funding for their debt obligations. The activities of the special purpose entities are contractually limited to purchasing assets from a subsidiary of Ambac, issuing medium-term notes (“MTNs”) to fund such purchases, executing derivative hedges and related administrative services. As of December 31, 2010, Ambac Assurance had financial guarantee insurance policies issued for all assets and MTNs owned and outstanding by the special purpose entities. Ambac does not consolidate these special purpose entities under the relevant accounting guidance for consolidation of variable interest entities. See Notes 2 and 10 to the Consolidated Financial Statements located in Part II, Item 8 for further information.

INVESTMENTS AND INVESTMENT POLICY

As of December 31, 2010, the consolidated investments of Ambac had an aggregate fair value of approximately $6.9 billion and an aggregate amortized cost of approximately $6.5 billion. The majority of these investments are primarily managed internally by officers of Ambac, who are experienced investment managers. A portion of the portfolio is managed by external investment managers. All investments are made in accordance with the general objectives and guidelines for investments approved by Ambac’s Board of Directors. These guidelines encompass credit quality, risk concentration and duration, and are periodically reviewed and revised as appropriate.

As of December 31, 2010, the Financial Guarantee investment portfolio had an aggregate fair value of approximately $5.7 billion and an aggregate amortized cost of approximately $5.4 billion. Ambac Assurance’s investment objectives are to achieve the highest book-yield on a diversified portfolio of fixed income investments while employing active asset/liability management practices to satisfy all operating and strategic liquidity needs. Ambac Assurance is subject to internal investment guidelines and is subject to limits on types and quality of investments imposed by the insurance laws and regulations of the States of Wisconsin and New York. In compliance with these laws, Ambac Assurance’s Board of Directors approves any changes or exceptions to the Investment Policy.

As described in “2010 Overview” located in Note 1 to the Consolidated Financial Statements in Item 8 of this Form 10-K, Ambac Assurance’s investment policies are subject to certain covenants made for the benefit of the Segregated Account and for the benefit of the Counterparties to the Settlement Agreement. Further, Ambac Assurance’s investment policies are subject to oversight by the rehabilitator pursuant to contracts entered into between Ambac Assurance and the Segregated Account and, therefore, such policies may change. Any such changes could adversely impact the performance of the investment portfolio.

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Beginning in 2008, Ambac Assurance purchased Ambac Assurance insured securities in the open market given their relative risk/reward characteristics and to mitigate the effect of potential future claim payments on operating results. Ambac Assurance financial guarantee policies related to these securities have been allocated to the Segregated Account as described in “2010 Overview” located in Note 1 to the Consolidated Financial Statements in Item 8 of this Form 10-K. As a result of the claims moratorium on such policies, payments on these investments were adversely impacted.

As of December 31, 2010, the Financial Services investment portfolio had an aggregate fair value of approximately $1.1 billion and an aggregate amortized cost of approximately $1.1 billion. The investment objectives are to invest primarily in high-grade securities that produce sufficient cash flow to satisfy all investment agreement liabilities and intercompany obligations. The investment portfolio is subject to internal investment guidelines. Such guidelines set forth minimum credit rating requirements and credit risk concentration limits.

The following tables provide certain information concerning the investments of Ambac: