Filed Pursuant to Rule 424(b)(5)
Registration No. 333-152892

CALCULATION OF REGISTRATION FEE

Title of Each Class of
Securities to be Registered

   
   
  Maximum
Aggregate
Offering Price(1)

   
  Amount to be
Registered(1)

  Maximum Offering
Price Per Unit

  Amount of
Registration Fee(2)


 

Common Shares, par value U.S. $0.01 per share

  27,512,600   $20.90   $575,013,340   $32,086.00

 

(1)
Includes common shares that may be purchased by the underwriters pursuant to their option to purchase additional shares.

(2)
The filing fee is calculated in accordance with Rule 457(r) under the Securities Act of 1933. Registration fees of $3,726 with respect to the Registration Statement on Form S-3 (File No. 333-125382) and $43,378 with respect to the Registration Statement on Form S-3 (File No. 333-125383), both of which were filed by Assured Guaranty Ltd. as of May 31, 2005, have been applied to the Registration Statement on Form S-3 (File No. 333-152892) of which this prospectus supplement and the accompanying prospectus forms a part. Of such previously paid registration fees, $32,086 is applied to this offering and $15,018 remains available for subsequent offerings.

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PROSPECTUS SUPPLEMENT
(To Prospectus dated June 16, 2009)


23,924,000 Shares

GRAPHIC

Assured Guaranty Ltd.

Common Shares


We are offering 23,924,000 common shares, par value $0.01 per share.

Our common shares are listed on the New York Stock Exchange under the symbol "AGO." The last reported closing price of our common shares on the New York Stock Exchange on November 30, 2009 was $22.68 per share.



Investing in our common shares involves risks. Before buying any of our common shares, you should read the discussion of material risks described in "Risk Factors" beginning on page S-4 of this prospectus supplement and included in our Quarterly Report for the quarterly period ended September 30, 2009, as well as the other information included or incorporated by reference in this prospectus supplement.



The underwriter has agreed to purchase the common shares from us at a price of $20.90 per share, which will result in net proceeds to us, after deducting estimated expenses related to this offering, of approximately $499,000,000. The underwriter proposes to offer the shares of common stock from time to time for sale in negotiated transactions or otherwise, at market prices prevailing at the time of sale, at prices related to such prevailing market prices or otherwise.

We have granted the underwriter an option to purchase up to 3,588,600 additional common shares on the same terms and conditions as set forth above if the underwriter sells more than 23,924,000 common shares in this offering. The underwriter can exercise this right at any time and from time to time, in whole or in part, within 30 days after the offering.



Neither the Securities and Exchange Commission nor any other regulatory body has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense. The securities are not being offered in any jurisdiction where the offer is not permitted.

Our common shares will be ready for delivery on or about December 4, 2009.



UBS Investment Bank



The date of this prospectus supplement is November 30, 2009.


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You should rely only on the information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus. We have not, and the underwriter has not, authorized anyone to provide you with different information. We are not making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus is accurate as of the date on the front of this prospectus supplement only. Our business, financial condition, results of operations and prospects may have changed since that date.

TABLE OF CONTENTS


Prospectus Supplement

About This Prospectus Supplement

    S-ii  

Forward-Looking Statements

    S-iii  

Prospectus Supplement Summary

    S-1  

Risk Factors

    S-4  

Use of Proceeds

    S-9  

Price Range of Common Shares and Dividend Policy

    S-9  

Material Tax Consequences

    S-9  

Underwriting

    S-10  

Notice to Investors

    S-12  

Legal Matters

    S-14  


Prospectus

About This Prospectus

    3  

Forward-Looking Statements

    3  

Assured Guaranty Ltd. 

    4  

Assured Guaranty US Holdings Inc. 

    5  

Use of Proceeds

    5  

Ratio of Earnings to Fixed Charges of Assured Guaranty

    5  

General Description of the Offered Securities

    5  

Description of Assured Guaranty Share Capital

    6  

Description of the Depositary Shares

    15  

Description of the Assured Guaranty Debt Securities

    17  

Description of the Assured Guaranty US Holdings Debt Securities and Assured Guaranty Guarantee

    29  

Description of the Warrants to Purchase Assured Guaranty Common Shares or Preferred Shares

    45  

Description of the Warrants to Purchase Debt Securities

    47  

Description of Stock Purchase Contracts and Stock Purchase Units

    48  

Plan of Distribution

    49  

Legal Matters

    51  

Experts

    51  

Enforceability Of Civil Liabilities Under United States Federal Securities Laws and Other Matters

    52  

Where You Can Find More Information

    52  


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About this prospectus supplement

This document is comprised of two parts. The first part is this prospectus supplement, which describes the specific terms of this offering of common shares and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference in this prospectus supplement and the accompanying prospectus. The second part, the accompanying prospectus, gives more general information, some of which may not apply to this offering. If the description of the offering varies between this prospectus supplement and the accompanying prospectus, you should rely on the information contained in this prospectus supplement.

You should rely only on information contained in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference in this prospectus supplement and the accompanying prospectus. We have not, and the underwriter has not, authorized anyone to provide you with information that is different. The information in this prospectus supplement and the accompanying prospectus may only be accurate as of the date of this prospectus supplement.

It is important for you to read and consider all information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus in making your investment decision. You should also read and consider the information in the documents to which we have referred you in "Where You Can Find More Information" in this prospectus supplement.

We have obtained consent from the Bermuda Monetary Authority for the issue and transfer of our common shares to and between persons regarded as non-residents in Bermuda for exchange control purposes, provided our common shares remain listed on an appropriate stock exchange, which includes the New York Stock Exchange, Inc. ("NYSE") Issues and transfers of common shares to any person regarded as resident in Bermuda for exchange control purposes may require the specific prior approval from the Bermuda Monetary Authority. In addition, this prospectus supplement and the accompanying prospectus will be filed with the Registrar of Companies in Bermuda in accordance with Bermuda law. The Bermuda Monetary Authority and Registrar of Companies accept no responsibility for the financial soundness of any proposal or for the correctness of any of the statements made or opinions expressed in this prospectus supplement.

Any person who, directly or indirectly, becomes a holder of at least 10 percent, 20 percent, 33 percent or 50 percent of the common shares must notify the Bermuda Monetary Authority in writing within 45 days of becoming such a holder or 30 days from the date they have knowledge of having such a holding, whichever is later. The Bermuda Monetary Authority may, by written notice, object to such a person if it appears to the Bermuda Monetary Authority that the person is not fit and proper to be such a holder. The Bermuda Monetary Authority may require the holder to reduce its holding of our common shares and direct, among other things, that voting rights attaching to the common shares shall not be exercisable. A person that does not comply with such a notice or direction from the Bermuda Monetary Authority will be guilty of an offence.

For so long as we have as a subsidiary an insurer registered under the Insurance Act (Bermuda), the Bermuda Monetary Authority may at any time, by written notice, object to a person holding 10 percent or more of our common shares if it appears to the Bermuda Monetary Authority that the person is not or is no longer fit and proper to be such a holder. In such a case, the Bermuda Monetary Authority may require the shareholder to reduce its holding of our common shares and direct, among other things, that such shareholder's voting rights attaching to the common shares shall not be exercisable. A person who does not comply with such a notice or direction from the Bermuda Monetary Authority will be guilty of an offence.

References in this prospectus supplement and the accompanying prospectus to "Assured Guaranty," "Assured," "we," "us," "our" and the "Company," refer to Assured Guaranty Ltd. and, unless the context otherwise requires or unless otherwise stated, its subsidiaries.

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Forward-looking statements

This prospectus supplement and the accompanying prospectus, and the documents incorporated herein by reference, may contain "forward looking statements" within the meaning of Section 27A of the Securities Act of 1933 as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). These forward-looking statements may include forward-looking statements which reflect our current views with respect to future events and financial performance. These statements include forward-looking statements both with respect to us specifically and the insurance and reinsurance industries in general. Statements which include the words "expect," "intend," "plan," "believe," "project," "anticipate," "may," "will," "continue," "further," "seek" and similar words or statements of a future or forward-looking nature identify forward-looking statements for purposes of the federal securities laws or otherwise. All forward-looking statements address matters that involve risks and uncertainties. These risks and uncertainties include, but are not limited to, economic, competitive, legal, governmental and technological factors. Accordingly, there are or will be important factors that could cause our actual results to differ materially from those indicated in these statements. We believe that these factors include the following:

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The foregoing review of important factors should not be construed as exhaustive, and should be read in conjunction with the other cautionary statements that are included in our periodic reports filed with the SEC. We undertake no obligation to update publicly or review any forward-looking statement, whether as a result of new information, future developments or otherwise.

If one or more of these or other risks or uncertainties materialize, or if our underlying assumptions prove to be incorrect, actual results may vary materially from what we projected. Any forward-looking statements you read in this prospectus supplement, in the accompanying prospectus, or in the documents incorporated by reference reflect our current views with respect to future events and are subject to these and other risks, uncertainties and assumptions relating to our operations, results of operations, growth strategy and liquidity.

For these statements, we claim the protection of the safe harbor for forward-looking statements contained in Section 27A of the Securities Act and Section 21E of the Exchange Act.

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Prospectus Supplement Summary

This summary highlights basic information about Assured Guaranty and this offering. Because it is a summary, it does not contain all of the information that you should consider before investing in the common shares. You should read this entire prospectus supplement, the accompanying prospectus and the documents that we have filed with the SEC that are incorporated by reference in this prospectus supplement and the accompanying prospectus, including the financial statements and notes thereto, carefully before making an investment decision.

ASSURED GUARANTY LTD.

Assured Guaranty Ltd. is a Bermuda based holding company that provides, through its operating subsidiaries, credit enhancement products to the public finance, structured finance and mortgage markets. Credit enhancement products are financial guaranties or other types of financial support, including credit derivatives, that improve the credit of underlying debt obligations. We offer credit enhancement products in both financial guaranty insurance and credit derivative form.

Our principal operating subsidiaries are Assured Guaranty Municipal Corp. (formerly Financial Security Assurance Inc.) ("AGM"), Assured Guaranty Corp. ("AGC") and Assured Guaranty Re Ltd. ("AG Re").

Assured Guaranty Ltd. has four principal business segments: (1) financial guaranty direct, which includes transactions whereby we provide an unconditional and irrevocable guaranty that indemnifies the holder of a financial obligation against non-payment of principal and interest when due, and could take the form of a credit derivative; (2) financial guaranty reinsurance, which includes agreements whereby we are a reinsurer and agree to indemnify a primary insurance company against part or all of the loss which the latter may sustain under a policy it has issued; (3) mortgage guaranty, which includes mortgage guaranty insurance and reinsurance whereby we provide protection against the default of borrowers on mortgage loans; and (4) other, which includes lines of business in which we are no longer active.

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RECENT DEVELOPMENTS

Moody's Ratings—On November 12, 2009, Moody's Investors Service ("Moody's") downgraded the insurance financial strength, debt and issuer ratings of Assured Guaranty and certain of our subsidiaries. AGC and Assured Guaranty (UK) Ltd.'s ("AG UK") insurance financial strength ratings were downgraded to Aa3 from Aa2 and AG Re, AGRO and Assured Guaranty Mortgage Insurance Company's ("AGMIC") insurance financial strength ratings were downgraded to A1 from Aa3. All of such ratings are on review for possible downgrade. Moody's stated that if we fully implemented certain capital strengthening initiatives, Moody's could conclude the rating review with a confirmation of the ratings of AGC and AG UK at the Aa3 level with a negative outlook. Moody's further stated, however, that absent such initiatives, Moody's expected to lower such ratings into the single-A range. Moody's stated that a key focus of its capital adequacy analysis was the evaluation of our exposure to mortgage-related losses. At the same time, Moody's affirmed the Aa3 insurance financial strength ratings of AGM and its affiliated insurance operating companies; all of such ratings have been assigned a negative outlook.

In response to Moody's rating action, we announced our intention to implement a capital relief plan involving the cession of a portfolio of transactions to a third party reinsurer, intercompany capital support and approximately $300 million of additional capital. As a result of raising approximately $500 million of additional capital in this offering, we currently do not expect to complete the third party reinsurance arrangement portion of this plan.

Fitch Ratings—On October 12, 2009, Fitch Ratings ("Fitch") downgraded the debt and insurer financial strength ratings of our subsidiaries, as applicable, stating that its downgrade was based on its expectations of credit losses arising from our residential mortgage securitization exposures, as well as other areas of concern in the insured portfolio of AGC and AG Re, particularly their exposure to trust preferred collateralized debt obligations ("CDOs"). Fitch downgraded the insurer financial strength ratings of AGC and AG UK to AA- from AA and the insurer financial strength ratings of AGM, FSA Insurance Company, Financial Security Assurance International Ltd. and Financial Security Assurance (U.K.) Ltd to AA from AA+. It also downgraded the debt ratings of Assured Guaranty US Holdings Inc. ("AGUS") to A- from A, the senior debt ratings of Financial Security Assurance Holdings Ltd. ("FSAH") to A- from A+ and its subordinated debt ratings to BBB+ from A. It affirmed the insurer financial strength ratings of AG Re, AGRO and AGMIC at AA-. All of the above ratings have been assigned a negative outlook.

S&P Ratings—On July 1, 2009, Standard & Poor's Ratings Services, a division of The McGraw-Hill Companies, Inc. ("S&P"), published a Research Update in which it affirmed its AAA counterparty credit and financial strength ratings on AGC and AGM. At the same time, S&P revised its outlook on AGC and AG UK to negative from stable and continued its negative outlook on AGM. S&P cited as a rationale for its actions the large single risk concentration exposure that we and AGM retain to Belgium and France prior to the posting of collateral by Dexia S.A. ("Dexia") in October 2011, all in connection with our July 2009 acquisition of FSAH (the "Acquisition"). In addition, the outlook also reflected S&P's view that the change in the competitive dynamics of the industry—with the potential entrance of new competitors, alternative forms of credit enhancement and limited insurance penetration in the U.S. public finance market—could hurt the companies' business prospects.



Investing in our common shares includes risks. See "Risk Factors" beginning on page S-4 of this prospectus supplement.

Our principal executive officers are located at 30 Woodbourne Avenue, Hamilton HM 08, Bermuda, and our telephone number is (441) 279-5700. Our Internet website address is www.assuredguaranty.com. The information on or connected to our website is not incorporated by reference in this prospectus supplement or the accompanying prospectus, and you should not consider them to be a part of this prospectus supplement or the accompanying prospectus.

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THE OFFERING

Issuer   Assured Guaranty Ltd.

Common shares offered

 

23,924,000

Option purchase additional shares

 

We have granted the underwriter a 30-day option to purchase up to an aggregate of 3,588,600 common shares if the underwriter sells more than 23,924,000 common shares in this offering.

Common shares to be outstanding after the offering

 

180,528,868 (or 184,117,468 if the underwriter exercises its overallotment option in full).

Use of proceeds

 

We intend to use the net proceeds of this offering for general corporate purposes and may contribute some portion of the net proceeds to the capital of our subsidiary, Assured Guaranty Corp., which will use this contribution for its general corporate purposes.

NYSE symbol

 

AGO

Risk factors

 

Investing in our common shares involves risks. Before buying any of our common shares, you should read the discussion of material risks described in "Risk Factors" beginning on page S-4 of this prospectus supplement and included in our Quarterly Report for the quarterly period ended September 30, 2009, as well as the other information included or incorporated by reference in this prospectus supplement.

The number of common shares that will be outstanding after this offering is based on the 156,604,868 common shares outstanding as of November 13, 2009. The number of common shares expected to be outstanding after this offering excludes:

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Risk factors

Any investment in the common shares involves a high degree of risk. You should carefully consider the risks described below, as well as those discussed under "Risk Factors" in our Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2009, incorporated by reference herein, before making a decision to invest in the common shares. The risk factors related to our business are set forth in the Quarterly Report on Form 10-Q referred to above. The risks and uncertainties described below are not the only ones facing us. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also have a material adverse effect on our business and operations.

If any of the matters included in the following risks were to occur, our business, financial condition, results of operations, cash flows or prospects could be materially adversely affected. In such case, you may lose all or part of your original investment.

For purposes of the discussion below, the term "U.S. Person" means: (i) an individual citizen or resident of the United States, (ii) a partnership or corporation created or organized in or under the laws of the United States or under the laws of any political subdivision thereof, (iii) an estate the income of which is subject to U.S. federal income taxation regardless of its source, (iv) a trust if either (x) a court within the United States is able to exercise primary supervision over the administration of such trust and one or more U.S. Persons have the authority to control all substantial decisions of such trust or (y) the trust has a valid election in effect to be treated as a U.S. Person for U.S. federal income tax purposes or (v) any other person or entity that is treated for U.S. federal income tax purposes as if it were one of the foregoing.

We and certain of our foreign subsidiaries may be subject to U.S. tax.

AGRO and Financial Security Assurance (U.K.) Ltd. ("FSA UK") have each elected to be classified as a U.S. domestic entity for all U.S. federal tax purposes, and thus will be subject to U.S. taxation on their respective net income. We manage our business so that Assured Guaranty Ltd., AG Re and each of our U.K. subsidiaries other than FSA UK operate in such a manner that none of them should be subject to U.S. federal tax (other than U.S. excise tax on insurance and reinsurance premium income attributable to insuring or reinsuring U.S. risks, and U.S. withholding tax on certain U.S. source investment income). However, because there is considerable uncertainty as to the activities which constitute being engaged in a trade or business within the United States, we cannot be certain that the U.S. Internal Revenue Service ("IRS") will not contend successfully that Assured Guaranty Ltd. or any of its foreign subsidiaries not otherwise subject to U.S. net income taxation is/are engaged in a trade or business in the United States. If Assured Guaranty Ltd. or any of such foreign subsidiaries were considered to be engaged in a trade or business in the United States, each such company could be subject to U.S. corporate income and branch profits taxes on the portion of its earnings effectively connected to such U.S. business.

Assured Guaranty Ltd. and our Bermuda subsidiaries may become subject to taxes in Bermuda after March 2016, which may have a material adverse effect on our results of operations and on your investment.

The Bermuda Minister of Finance, under Bermuda's Exempted Undertakings Tax Protection Act 1966, as amended, has given Assured Guaranty Ltd., AG Re and AGRO an assurance that if any legislation is enacted in Bermuda that would impose tax computed on profits or income, or computed on any capital asset, gain or appreciation, or any tax in the nature of estate duty or inheritance tax, then subject to certain limitations the imposition of any such tax will not be applicable to Assured Guaranty Ltd. or our Bermuda subsidiaries, or any of Assured Guaranty Ltd.'s or our Bermuda

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Risk factors



subsidiaries' operations, shares, debentures or other obligations until March 28, 2016. Given the limited duration of the Minister of Finance's assurance, we cannot be certain that we will not be subject to Bermuda tax after March 2016.

The Organization for Economic Cooperation and Development and the European Union are considering measures that might increase our taxes and reduce our net income.

The Organization for Economic Cooperation and Development (the "OECD") has published reports and launched a global dialogue among member and non-member countries on measures to limit harmful tax competition. These measures are largely directed at counteracting the effects of tax havens and preferential tax regimes in countries around the world. According to the OECD, Bermuda is a jurisdiction that has substantially implemented the internationally agreed tax standard and as such is listed on the OECD "white list." We are not able to predict whether any changes will be made to this classification or whether such changes will subject us to additional taxes.

U.S. persons who hold 10% or more of our shares directly or through foreign entities may be subject to taxation under U.S. "CFC" rules.

Each 10% U.S. shareholder of a foreign corporation that is a controlled foreign corporation ("CFC") for an uninterrupted period of 30 days or more during a taxable year, and who owns shares in the foreign corporation directly or indirectly through foreign entities on the last day of the foreign corporation's taxable year on which it is a CFC, must include in its gross income for U.S. federal income tax purposes its pro rata share of the CFC's "subpart F income," even if the subpart F income is not distributed.

We believe that because of the dispersion of the share ownership in Assured Guaranty Ltd., provisions in our Bye-Laws that limit voting power, contractual limits on voting power and other factors, no U.S. Person who owns our common shares directly or indirectly through foreign entities should be treated as a 10% U.S. shareholder of Assured Guaranty Ltd. or of any of our foreign subsidiaries. It is possible, however, that the IRS could challenge the effectiveness of these provisions and that a court could sustain such a challenge, in which case such U.S. Person may be subject to taxation under U.S. tax rules.

U.S. Persons who hold shares may be subject to U.S. income taxation at ordinary income rates on their proportionate share of our related person insurance income.

Under applicable regulations, if:

then a U.S. Person who owns our shares (directly or indirectly through foreign entities) on the last day of the taxable year would be required to include in its income for U.S. federal income tax purposes such person's pro rata share of the insurance subsidiary's RPII for the entire taxable year, determined as if such RPII were distributed proportionately only to U.S. Persons at that date, regardless of

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whether such income is distributed. In addition, any RPII that is includible in the income of a U.S. tax-exempt organization may be treated as unrelated business taxable income.

The amount of RPII earned by an insurance subsidiary (such as AG Re) (generally, premium and related investment income from the direct or indirect insurance or reinsurance of any direct or indirect U.S. holder of shares or any person related to such holder) will depend on a number of factors, including the geographic distribution of the insurance subsidiary's business and the identity of persons directly or indirectly insured or reinsured by an insurance subsidiary (such as AG Re). We believe that no insurance subsidiary had in prior years of operation, nor should in the foreseeable future have, either RPII income which equals or exceeds 20% of gross insurance income or have direct or indirect insureds, as provided for by RPII rules, of the insurance subsidiary (and related persons) directly or indirectly own 20% or more of either the voting power or value of Assured Guaranty Ltd.'s shares. However, we cannot be certain that this will be the case because some of the factors which determine the extent of RPII may be beyond our control.

U.S. Persons who dispose of our shares may be subject to U.S. income taxation at ordinary incometax rates on a portion of their gain, if any.

The meaning of the RPII provisions and the application thereof to Assured Guaranty Ltd. and the insurance subsidiaries is uncertain. The RPII rules provide that if a U.S. Person disposes of shares in a foreign insurance corporation in which U.S. Persons own 25% or more of the shares (even if the amount of gross RPII is less than 20% of the corporation's gross insurance income and the ownership of its shares by direct or indirect insureds and related persons is less than the 20% threshold), any gain from the disposition will generally be treated as dividend income to the extent of the holder's share of the corporation's undistributed earnings and profits that were accumulated during the period that the holder owned the shares. This provision applies whether or not such earnings and profits are attributable to RPII. In addition, such a holder will be required to comply with certain reporting requirements, regardless of the amount of shares owned by the holder.

In the case of Assured Guaranty Ltd.'s shares, these RPII rules should not apply to dispositions of shares because Assured Guaranty Ltd. is not itself directly engaged in the insurance business. However, the RPII provisions have never been interpreted by the courts or the U.S. Treasury Department in final regulations, and regulations interpreting the RPII provisions of the Internal Revenue Code of 1986, as amended (the "Code") exist only in proposed form. It is not certain whether these regulations will be adopted in their proposed form, what changes or clarifications might ultimately be made thereto, or whether any such changes, as well as any interpretation or application of RPII by the IRS, the courts, or otherwise, might have retroactive effect. The U.S. Treasury Department has authority to impose, among other things, additional reporting requirements with respect to RPII.

U.S. Persons who hold common shares will be subject to adverse tax consequences if we are considered to be a "passive foreign investment company" for U.S. federal income tax purposes.

If Assured Guaranty Ltd. is considered a passive foreign investment company ("PFIC") for U.S. federal income tax purposes, a U.S. Person who owns any shares of Assured Guaranty Ltd. will be subject to adverse tax consequences that could materially adversely affect its investment, including subjecting the investor to both greater tax liability than might otherwise apply and tax on amounts in advance of when tax would otherwise be imposed. We believe that Assured Guaranty Ltd. is not, and currently do not expect Assured Guaranty Ltd. to become, a PFIC for U.S. federal income tax purposes; however, we cannot assure you that Assured Guaranty Ltd. will not be deemed a PFIC by the IRS.

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There are currently no regulations regarding the application of the PFIC provisions to an insurance company. New regulations or pronouncements interpreting or clarifying these rules may be forthcoming. We cannot predict what impact, if any, such guidance would have on an investor that is subject to U.S. federal income taxation.

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

Legislation has been introduced in the U.S. Congress intended to eliminate certain perceived tax advantages to companies (including insurance companies) that have legal domiciles outside the United States but have certain U.S. connections. For example, legislation has been introduced in Congress to limit the deductibility of reinsurance premiums paid by U.S. insurance companies to foreign affiliates and impose additional limits on deductibility of interest of foreign owned U.S. corporations. Another legislative proposal would treat a foreign corporation that is primarily managed and controlled in the United States as a U.S. corporation for U.S federal income tax purposes. Further, legislation has been introduced to override the reduction or elimination under a U.S. tax treaty of U.S. withholding tax on certain U.S. source investment income in the case of a deductible related party payment made by a U.S. member of a foreign controlled group to a foreign member of the group organized in a tax treaty country to the extent that the ultimate foreign parent corporation would not enjoy the treaty benefits with respect to such payments. It is possible that this or similar legislation could be introduced in and enacted by the current Congress or future Congresses that could have an adverse impact on us or our shareholders.

U.S. federal income tax laws and interpretations regarding whether a company is engaged in a trade or business within the United States, is a PFIC, or whether U.S. Persons would be required to include in their gross income the "subpart F income" of a CFC or RPII are subject to change, possibly on a retroactive basis. There currently are no regulations regarding the application of the PFIC rules to insurance companies, and the regulations regarding RPII are still in proposed form. New regulations or pronouncements interpreting or clarifying such rules may be forthcoming. We cannot be certain if, when, or in what form such regulations or pronouncements may be implemented or made, or whether such guidance will have a retroactive effect.

On November 6, 2009, the United States enacted new tax legislation that, among other things, extends the period over which companies may carry back net operating losses to recover previously paid income taxes. Under U.S. generally accepted accounting principles, the effects of changes in tax law are recorded in the period in which the law is enacted. We are currently reviewing the new legislation and will reflect the implications on our financial position and results of operations, if any, in our year-end financial statements.

Recharacterization by the IRS of our U.S. federal tax treatment of losses on our CDS portfolio can adversely affect our financial position.

As part of our financial guaranty business, each of AGC and AGM has sold credit protection by insuring CDS entered into with various financial institutions. AGC's and AGM's CDS portfolio had experienced mark-to-market losses of $1,148 million as of September 30, 2009, which are only deductible for U.S. federal income tax purposes upon realization and, consequently, generate a significant deferred tax asset based on AGC's and AGM's intended treatment of such losses as ordinary insurance losses upon realization. The U.S. federal income tax treatment of CDS is an unsettled area of the tax law. As such, it is possible that the IRS may decide that the losses generated by AGC's and AGM's CDS business should be characterized as capital rather than ordinary insurance losses, which could materially adversely affect our financial condition.

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An ownership change under Section 382 of the Code could have adverse U.S. federal tax consequences.

If Assured Guaranty Ltd. were to issue equity securities in the future, including in connection with any strategic transaction, or if previously issued securities of Assured Guaranty were to be sold by the current holders, we may experience an "ownership change" within the meaning of Section 382 of the Code. In general terms, an ownership change would result from transactions increasing the aggregate ownership of certain shareholders in Assured Guaranty Ltd.'s shares by more than 50 percentage points over a testing period (generally three years). If an ownership change occurred, our ability to use certain tax attributes, including certain built-in losses, credits, deductions or tax basis and/or our ability to continue to reflect the associated tax benefits as assets on our balance sheet, may be limited. We cannot give any assurance that Assured Guaranty Ltd. will not undergo an ownership change at a time when these limitations could materially adversely affect our financial condition.

FSAH likely experienced an ownership change under Section 382 of the Code.

In connection with the Acquisition, FSAH likely experienced an "ownership change" within the meaning of Section 382 of the Code. We have concluded that, as applied to FSAH, the Section 382 limitations described in "—An ownership change under Section 382 of the Code could have adverse U.S. federal tax consequences" above are unlikely to have any material tax or accounting consequences. However, this conclusion is based on a variety of assumptions, including our estimates regarding the amount and timing of certain deductions and future earnings, any of which could be incorrect. Accordingly, we cannot assure you that these limitations would not have an adverse effect on our financial condition or that such adverse effects would not be material.

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Use of proceeds

The net proceeds from the sale of the common shares offered hereby (after deducting underwriting discounts and commissions and estimated expenses of the offering) are estimated to be approximately $499,000,000 ($574,000,000 if the underwriter's over-allotment option is exercised in full).

We intend to use the net proceeds of this offering for general corporate purposes and may contribute some portion of the net proceeds to the capital of our subsidiary, Assured Guaranty Corp., which will use this contribution for its general corporate purposes.

Price range of common shares and dividend policy

Our common shares have been listed for trading on the NYSE under the symbol "AGO" since April 22, 2004. The following table sets forth on a per share basis the high and low sales prices for consolidated trading in our common shares as reported on the NYSE and dividends for the quarters indicated.

 
  Price range of common shares    
 
 
  Dividend
paid
per share

 
 
  High
  Low
 
   

Fiscal Year Ended 2007

                   
 

First Quarter

  $ 28.40   $ 25.90   $ 0.04  
 

Second Quarter

    31.99     26.65     0.04  
 

Third Quarter

    30.22     21.32     0.04  
 

Fourth Quarter

    29.46     13.34     0.04  

Fiscal Year Ended 2008

                   
 

First Quarter

  $ 26.98   $ 16.53   $ 0.045  
 

Second Quarter

    27.58     17.94     0.045  
 

Third Quarter

    20.64     7.95     0.045  
 

Fourth Quarter

    16.65     5.49     0.045  

Fiscal Year Ended 2009

                   
 

First Quarter

  $ 12.79   $ 2.69   $ 0.045  
 

Second Quarter

    16.07     6.48     0.045  
 

Third Quarter

    21.06     10.64     0.045  
 

Fourth Quarter (through November 30, 2009)

    28.14     16.25      

The closing price of our common shares on the NYSE on November 30, 2009 was $22.68 per share.

As of November 13, 2009, there were approximately 15,000 holders of record of our common shares. This number excludes beneficial owners of common shares held in "street name."

Material tax consequences

For information regarding taxation of Assured Guaranty and its shareholders, see "Material Tax Considerations" in our Current Report on Form 8-K dated November 30, 2009, which is incorporated by reference in this prospectus supplement.

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Underwriting

UBS Securities LLC is acting as the underwriter and book-running manager of the offering. Subject to the terms and conditions stated in the underwriting agreement dated the date of this prospectus supplement, the underwriter has agreed to purchase, and we have agreed to sell to the underwriter, 23,924,000 common shares.

The underwriting agreement provides that the obligations of the underwriter to purchase the common shares included in this offering are subject to approval of legal matters by counsel and to other conditions. The underwriter is obligated to purchase all the common shares (other than those covered by the over-allotment option described below) if it purchases any of the common shares.

The underwriter has agreed to purchase the common shares from us at a price of $20.90 per share, which will result in net proceeds to us, after deducting estimated expenses related to this offering, of approximately $499.0 million, assuming no exercise of the over-allotment option granted to the underwriter, and $574.0 million, assuming full exercise of the over-allotment option. The underwriter proposes to offer the shares of common stock from time to time for sale in negotiated transactions or otherwise, at market prices prevailing at the time of sale, at prices related to such prevailing market prices or otherwise.

We have granted the underwriter an option to purchase up to 3,588,600 additional common shares at the same price per share as it is paying for the common shares shown in the table above. These additional common shares would cover sales by the underwriter that exceed the total number of shares referred to above. The underwriter may exercise this option at any time and from time to time, in whole or in part, within 30 days after the date of this prospectus supplement, but solely for the purpose of covering over-allotments, if any, in connection with this offering.

We estimate that our total expenses for this offering, net of underwriting discounts and commissions, will be approximately $1,000,000.

Our common shares are listed on the NYSE under the symbol "AGO."

In connection with this offering, the underwriter may engage in activities that stabilize, maintain or otherwise affect the price of our common shares, including:

Stabilizing transactions consist of bids or purchases made for the purpose of preventing or retarding a decline in the market price of our common shares while this offering is in progress. Stabilizing transactions may include making short sales of our common shares, which involves the sale by the underwriter of a greater number of common shares than it is required to purchase in this offering, and purchasing common shares from us or on the open market to cover positions created by short sales. Short sales may be "covered" shorts, which are short positions in an amount not greater than the underwriter's option to purchase additional shares referred to above, or may be "naked" shorts, which are short positions in excess of that amount. Syndicate covering transactions involve purchases of our common shares in the open market after the distribution has been completed in order to cover syndicate short positions.

The underwriter may close out any covered short position either by exercising its option to purchase additional shares, in whole or in part, or by purchasing shares in the open market. In making this determination, the underwriter will consider, among other things, the price of shares available for purchase in the open market compared to the price at which the underwriter may purchase shares as referred to above.

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A naked short position is more likely to be created if the underwriter is concerned that there may be downward pressure on the price of the common shares in the open market that could adversely affect investors who purchased in this offering. To the extent that the underwriter creates a naked short position, it will purchase shares in the open market to cover the position.

These activities may have the effect of raising or maintaining the market price of our common shares or preventing or retarding a decline in the market price of our common shares. As a result of these activities, the price of our common shares may be higher than the price that otherwise might exist in the open market. If the underwriter commences the activities, it may discontinue them at any time. The underwriter may carry out these transactions on the NYSE, in the over-the-counter market or otherwise.

Lock-Up Agreements.    We, WLR Recovery Fund IV, L.P., which owns approximately 10.2% of our outstanding common shares, and our directors and executive officers have entered into lock-up agreements with the underwriter. Under these agreements, subject to exceptions, we may not issue any new common shares, and those holders of common shares and options may not, directly or indirectly, offer, sell, contract to sell, pledge or otherwise dispose of or hedge any common shares or securities convertible into or exchangeable for common shares, or publicly announce the intention to do any of the foregoing, without the prior written consent of the underwriter for a period of 90 days from the date of this prospectus supplement. This consent may be given at any time without public notice. In addition, during this 90-day period, we have also agreed not to file any registration statement for any common shares or any securities convertible into or exercisable or exchangeable for common shares without the prior written consent of the underwriter and, except as required pursuant to any outstanding registration rights agreements.

Dexia S.A., which owns approximately 13.8% of our outstanding common shares, entered into a lock-up agreement with the underwriter. Under this agreement, subject to exceptions, Dexia S.A. may not, directly or indirectly, offer, sell, contract to sell, pledge or otherwise dispose of or hedge any common shares or securities convertible into or exchangeable for common shares, or publicly announce the intention to do any of the foregoing, without the prior written consent of the underwriter for a period of 45 days from the date of this prospectus supplement. This consent may be given at any time without public notice.

We will indemnify the underwriter against some liabilities, including liabilities under the Securities Act of 1933, as amended. If we are unable to provide this indemnification, we will contribute to payments the underwriter may be required to make in respect of those liabilities.

The underwriter and its affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, principal investment, hedging, financing and brokerage activities. The underwriter and its affiliates have provided, and may in the future provide, various investment banking, commercial banking and other financial services for us and our affiliates for which services they have received, and may in the future receive, customary fees.

In the ordinary course of its various business activities, the underwriter and its affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers and may at any time hold long and short positions in such securities and instruments. Such investment and securities activities may involve securities and instruments of Assured.

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Notice to investors

European Economic Area

In relation to each Member State of the European Economic Area, or EEA, which has implemented the Prospectus Directive (each, a "Relevant Member State"), with effect from, and including, the date on which the Prospectus Directive is implemented in that Relevant Member State, or the Relevant Implementation Date, an offer to the public of our securities which are the subject of the offering contemplated by this offering memorandum may not be made in that Relevant Member State, except that, with effect from, and including, the Relevant Implementation Date, an offer to the public in that Relevant Member State of our securities may be made at any time under the following exemptions under the Prospectus Directive, if they have been implemented in that Relevant Member State:

provided that no such offer of our securities shall result in a requirement for the publication by us or any underwriter or agent of a prospectus pursuant to Article 3 of the Prospectus Directive.

As used above, the expression "offered to the public" in relation to any of our securities in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and our securities to be offered so as to enable an investor to decide to purchase or subscribe for our securities, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State and the expression "Prospectus Directive" means Directive 2003/71/EC and includes any relevant implementing measure in each Relevant Member State.

The EEA selling restriction is in addition to any other selling restrictions set out in this offering memorandum.

United Kingdom

This offering memorandum is only being distributed to and is only directed at (1) persons who are outside the United Kingdom, (2) investment professionals falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, or Order; or (3) high net worth companies, and other persons to who it may lawfully be communicated, falling within Article 49(2)(a) to (d) of the Order, all such person together being referred to as "relevant persons." The securities are only available to, and any invitation, offer or agreement to subscribe, purchase or otherwise acquire such securities will be engaged in only with, relevant persons. Any person who is not a relevant person should not act or rely on this offering memorandum or any of its contents.

Switzerland

Our securities may not and will not be publicly offered, distributed or re-distributed in or from Switzerland, and neither this offering memorandum nor any other solicitation for investments in our securities may be communicated or distributed in Switzerland in any way that could constitute a public offering within the meaning of articles 652a or 1156 of the Swiss Federal Code of Obligations or of

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Article 2 of the Federal Act on Investment Funds of March 18, 1994. This offering memorandum may not be copied, reproduced, distributed or passed on to others without the underwriters' and agents' prior written consent. This offering memorandum is not a prospectus within the meaning of Articles 1156 and 652a of the Swiss Code of Obligations or a listing prospectus according to article 32 of the Listing Rules of the Swiss exchange and may not comply with the information standards required thereunder. We will not apply for a listing of our securities on any Swiss stock exchange or other Swiss regulated market and this offering memorandum may not comply with the information required under the relevant listing rules. The securities have not been and will not be approved by any Swiss regulatory authority. The securities have not been and will not be registered with or supervised by the Swiss Federal Banking Commission, and have not been and will not be authorized under the Federal Act on Investment Funds of March 18, 1994. The investor protection afforded to acquirers of investment fund certificates by the Federal Act on Investment Funds of March 18, 1994 does not extend to acquirers of our securities.

Hong Kong

Our securities may not be offered or sold in Hong Kong, by means of this offering memorandum or any document other than to persons whose ordinary business is to buy or sell shares, whether as principal or agent, or in circumstances which do not constitute an offer to the public within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong). No advertisement, invitation or document relating to our securities may be issued or may be in the possession of any person other than with respect to the securities which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder.

Singapore

This offering memorandum has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this offering memorandum and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of our securities may not be circulated or distributed, nor may our securities be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore, or SFA, (ii) to a relevant person pursuant to Section 275(1), or any person pursuant to Section 275(1A), and in accordance with the conditions specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA, in each case subject to compliance with conditions set forth in the SFA.

Where our securities are subscribed or purchased under Section 275 by a relevant person which is: (a) a corporation (which is not an accredited investor as defined in Section 4A of the SFA) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or (b) a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary of the trust is an individual who is an accredited investor; shares of that corporation or the beneficiaries' rights and interest (howsoever described) in that trust shall not be transferable for six months after that corporation or that trust has acquired the shares under Section 275 of the SFA, except: (1) to an institutional investor (for corporations under Section 274 of the SFA) or to a relevant person defined in Section 275(2) of the SFA, or any person pursuant to an offer that is made on terms that such shares of that corporation or such rights and interest in that trust are acquired at a consideration of not less than S$200,000 (or its equivalent in a foreign currency) for each transaction, whether such amount is to be paid for in cash or by exchange of securities or other assets, and further for corporations, in accordance with the conditions, specified in Section 275 of the SFA; (2) where no consideration is given for the transfer; or (3) where the transfer is by operation of law.

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Japan

Our securities have not been and will not be registered under the Securities and Exchange Law of Japan (the Securities and Exchange Law) and our securities will not be offered or sold, directly or indirectly, in Japan, or to, or for the benefit of, any resident of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan, or to a resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the Securities and Exchange Law and any other applicable laws, regulations and ministerial guidelines of Japan.

Australia

This offering memorandum is not a formal disclosure document and has not been lodged with the Australian Securities and Investments Commission. It does not purport to contain all information that an investor or their professional advisers would expect to find in a product disclosure statement for the purposes of Part 7.9 of the Corporations Act 2001 (Australia) in relation to the securities.

The securities are not being offered in Australia to "retail clients" as defined in section 761G of the Corporations Act 2001 (Australia). This offering is being made in Australia solely to "wholesale clients" as defined in section 761G of the Corporations Act 2001 (Australia) and as such no product disclosure statement in relation to the securities has been prepared.

This offering memorandum does not constitute an offer in Australia other than to wholesale clients. By submitting an application for our securities, you represent and warrant to us that you are a wholesale client. If any recipient is not a wholesale client, no applications for our securities will be accepted from such recipient. Any offer to a recipient in Australia, and any agreement arising from acceptance of such offer, is personal and may only be accepted by the recipient. In addition, by applying for our securities you undertake to us that, for a period of 12 months from the date of issue of the securities, you will not transfer any interest in the securities to any person in Australia other than a wholesale client.

Legal matters

Certain legal matters as to Bermuda law will be passed upon for us by Conyers Dill & Pearman, Hamilton, Bermuda. Certain legal matters as to U.S. law will be passed upon for us by Mayer Brown LLP, Chicago, Illinois. Certain legal matters in connection with this offering will be passed upon for the underwriter by Dewey & LeBoeuf LLP, New York, New York. Dewey & LeBoeuf LLP from time to time has represented us and our affiliates on various matters and may in the future continue to do so.

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PROSPECTUS

         GRAPHIC


Assured Guaranty Ltd.

Common Shares, Preferred Shares, Depositary Shares, Debt Securities,
Warrants to Purchase Common Shares,
Warrants to Purchase Preferred Shares,
Warrants to Purchase Debt Securities, Stock Purchase Contracts and
Stock Purchase Units




Assured Guaranty US Holdings Inc.

Debt Securities
Fully and Unconditionally Guaranteed by

Assured Guaranty Ltd.



        Assured Guaranty or Assured Guaranty US Holdings will provide the specific terms of these securities in supplements to this prospectus. The prospectus supplements may also add, update or change information contained in this prospectus. You should read this prospectus and any supplements carefully before you invest.

        Assured Guaranty's common shares are traded on the New York Stock Exchange under the symbol "AGO."

        None of the Securities and Exchange Commission, any state securities commission or any other regulatory body has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

        This prospectus may not be used to consummate sales of offered securities unless accompanied by a prospectus supplement.



        NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY OTHER REGULATORY BODY HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.



The date of this prospectus is June 16, 2009.




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        You should rely only on the information contained or incorporated by reference in this prospectus or any supplement. None of the registrants has authorized anyone else to provide you with different information. The securities offered by this prospectus are being offered only in states where the offer is permitted. You should not assume that the information in this prospectus or any supplement is accurate as of any date other than the date on the front of those documents. Our business, financial condition, results of operations and prospects may have changed since that date.

        We have obtained consent from the Bermuda Monetary Authority for the issue and transfer of shares to and between persons regarded as non-resident in Bermuda for exchange control purposes and for the issue and transfer of options, warrants, depositary receipts, rights, loan notes and other securities, subject to the condition that our shares are listed on an appointed stock exchange, which includes the New York Stock Exchange, Inc. Issues and transfers of shares to any person regarded as resident in Bermuda for exchange control purposes may require specific prior approval from the Bermuda Monetary Authority. The Bermuda Monetary Authority accepts no responsibility for the financial soundness of any proposal or for the correctness of any of the statements made or opinions expressed in this prospectus.

        Any person who, directly or indirectly, becomes a holder of at least 10 percent, 20 percent, 33 percent, or 50 percent of the common shares must notify the Bermuda Monetary Authority in writing within 45 days of becoming such a holder or 30 days from the date they have knowledge of having such a holding, whichever is later. The Bermuda Monetary Authority may, by written notice, object to such a person if it appears to the Bermuda Monetary Authority that the person is not fit and proper to be such a holder. The Bermuda Monetary Authority may require the holder to reduce their holding of common shares in the Company and direct, among other things, that voting rights attaching to the common shares shall not be exercisable. A person that does not comply with such a notice or direction from the Bermuda Monetary Authority will be guilty of an offence.

        For so long as we have as a subsidiary an insurer registered under the Insurance Act 1978 (as amended) of Bermuda, the Bermuda Monetary Authority may at any time, by written notice, object to a person holding 10 percent or more of the Company's common shares if it appears to the Bermuda Monetary Authority that the person is not or is no longer fit and proper to be such a holder. In such a case, the Bermuda Monetary Authority may require the shareholder to reduce its holding of common shares in the Company and direct, among other things, that such shareholder's voting rights attaching to the common shares shall not be exercisable. A person who does not comply with such a notice or direction from the Bermuda Monetary Authority will be guilty of an offence.

        Before a person can acquire control of a U.S.-domiciled insurance company, prior written approval must be obtained from the insurance commissioner of the states where the insurer is domiciled or deemed commercially domiciled. Generally, state statutes provide that control over an insurer is presumed to exist if any person, directly or indirectly, owns, controls, holds with the power to vote, or holds proxies representing, 10% or more of the voting securities of the insurer. Because a person acquiring 10% or more of our common shares would indirectly control the same percentage of the stock of our U.S. insurance company subsidiaries, the insurance change of control laws of Maryland and New York would likely apply to such a transaction. Prior to granting approval of an application to acquire control of an insurer, the state insurance commissioner will consider such factors as the financial strength of the applicant, the integrity and management of the applicant's Board of Directors and executive officers, the acquirer's plans for the management of the applicant's Board of Directors and executive officers, the acquirer's plans for the future operations of the insurer and any anti-competitive results that may arise from the consummation of the acquisition of control.

        The Financial Services and Markets Act 2000 ("FSMA") regulates the acquisition of "control" of any UK insurance company authorized under FSMA. Any company or individual that (together with its or his associates) directly or indirectly acquires 10% or more of the shares in a UK authorized insurance company or its parent company, or is entitled to exercise or control the exercise of 10% or more of the voting power in such authorized insurance company or its parent company, would be considered to have acquired "control" for the purposes of the relevant legislation, as would a person


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who had significant influence over the management of such authorized insurance company or its parent company by virtue of his shareholding or voting power in either. Under FSMA, any person proposing to acquire "control" of a UK authorized insurance company must give prior notification to the FSA UK of its intention to do so. The Financial Services Authority ("FSA UK") then has three months to consider that person's application to acquire "control." In considering whether to approve such application, the FSA UK must be satisfied that both the acquirer is a "fit and proper" person to have "control" and that the interests of consumers would not be threatened by such acquisition of "control." "Consumers" in this context includes all persons who may use the services of the authorized insurance company. Failure to make the relevant prior application could result in action being taken by the FSA UK.

        In this prospectus, references to "dollars" and "$" are to United States currency, and the terms "United States" and "U.S." mean the United States of America, its states, its territories, its possessions and all areas subject to its jurisdiction.


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TABLE OF CONTENTS

 
  Page

ABOUT THIS PROSPECTUS

  3

FORWARD-LOOKING STATEMENTS

  3

ASSURED GUARANTY LTD

  4

ASSURED GUARANTY US HOLDINGS INC

  5

USE OF PROCEEDS

  5

RATIO OF EARNINGS TO FIXED CHARGES OF ASSURED GUARANTY

  5

GENERAL DESCRIPTION OF THE OFFERED SECURITIES

  5

DESCRIPTION OF ASSURED GUARANTY SHARE CAPITAL

  6

DESCRIPTION OF THE DEPOSITARY SHARES

  15

DESCRIPTION OF THE ASSURED GUARANTY DEBT SECURITIES

  17

DESCRIPTION OF THE ASSURED GUARANTY US HOLDINGS DEBT SECURITIES AND ASSURED GUARANTY GUARANTEE

  29

DESCRIPTION OF THE WARRANTS TO PURCHASE ASSURED GUARANTY COMMON SHARES OR PREFERRED SHARES

  45

DESCRIPTION OF THE WARRANTS TO PURCHASE DEBT SECURITIES

  47

DESCRIPTION OF STOCK PURCHASE CONTRACTS AND STOCK PURCHASE UNITS

  48

PLAN OF DISTRIBUTION

  49

LEGAL MATTERS

  51

EXPERTS

  51

ENFORCEABILITY OF CIVIL LIABILITIES UNDER UNITED STATES FEDERAL SECURITIES LAWS AND OTHER MATTERS

  52

WHERE YOU CAN FIND MORE INFORMATION

  52

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ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement that Assured Guaranty and Assured Guaranty US Holdings filed with the Securities and Exchange Commission utilizing a "shelf" registration process, relating to the common shares, preferred shares, depositary shares, debt securities, debt securities guarantee, warrants, stock purchase contracts and stock purchase units described in this prospectus. Under this shelf process, any or all of Assured Guaranty and Assured Guaranty US Holdings may sell the securities described in this prospectus in one or more offerings. This prospectus provides you with a general description of the securities Assured Guaranty or Assured Guaranty US Holdings may offer. This prospectus does not contain all of the information set forth in the registration statement as permitted by the rules and regulations of the SEC. For additional information regarding Assured Guaranty and Assured Guaranty US Holdings and the offered securities, please refer to the registration statement. Each time Assured Guaranty or Assured Guaranty US Holdings sells securities, it will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any prospectus supplement together with additional information described under the heading "Where You Can Find More Information."


FORWARD-LOOKING STATEMENTS

        This prospectus, including the documents we incorporate by reference, contains "forward-looking statements" as that term is defined under the Private Securities Litigation Reform Act of 1995. These forward-looking statements may include forward-looking statements which reflect our current views with respect to future events and financial performance. These statements include forward-looking statements both with respect to us specifically and the insurance and reinsurance industries in general. Statements which include the words "expect," "intend," "plan," "believe," "project," "anticipate," "may," "will," "continue," "further," "seek," and similar words or statements of a future or forward-looking nature identify forward-looking statements for purposes of the federal securities laws or otherwise. All forward-looking statements address matters that involve risks and uncertainties. Accordingly, there are or will be important factors that could cause our actual results to differ materially from those indicated in these statements. We believe that these factors include the following:

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        The foregoing review of important factors should not be construed as exhaustive, and should be read in conjunction with the other cautionary statements that are included in our periodic reports filed with the SEC. We undertake no obligation to update publicly or review any forward-looking statement, whether as a result of new information, future developments or otherwise.

        If one or more of these or other risks or uncertainties materialize, or if our underlying assumptions prove to be incorrect, actual results may vary materially from what we projected. Any forward-looking statements you read in this prospectus or in the documents incorporated by reference reflect our current views with respect to future events and are subject to these and other risks, uncertainties and assumptions relating to our operations, results of operations, growth strategy and liquidity.

        For these statements, we claim the protection of the safe harbor for forward-looking statements contained in Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934.


ASSURED GUARANTY LTD.

        Assured Guaranty Ltd. (together with its subsidiaries, hereafter "Assured Guaranty," "we," "us," "our" or the "Company") is a Bermuda-based holding company providing, through its operating subsidiaries, credit enhancement products to the public finance, structured finance and mortgage markets. Credit enhancement products are financial guarantees or other types of support, including credit derivatives, which improve the credit of underlying debt obligations. We apply our credit expertise, risk management skills and capital markets experience to develop insurance, reinsurance and derivative products that meet the credit enhancement needs of our customers. Under a reinsurance agreement, the reinsurer, in consideration of a premium paid to it, agrees to indemnify another insurer, called the ceding company, for part or all of the liability of the ceding company under one or more insurance policies that the ceding company has issued. A derivative is a financial instrument whose characteristics and value depend upon the characteristics and value of an underlying security or commodity. We market our products directly and through financial institutions, serving the U.S. and international markets.

        Our principal operating subsidiaries are Assured Guaranty Corp. ("AGC") and Assured Guaranty Re Ltd. ("AG Re"). AGC, a Maryland-domiciled insurance company, was organized in 1985 and commenced operations in January 1988. AGC provides insurance and reinsurance of investment grade financial guaranty exposures, including municipal and non-municipal reinsurance, and credit default swap transactions.

        AG Re is incorporated under the laws of Bermuda and is licensed as a Class 3-B Insurer and a Long-Term Insurer under the Insurance Act 1978 and related regulations of Bermuda. AG Re writes business as a direct reinsurer of third-party primary insurers and as a reinsurer/retrocessionaire of certain affiliated companies and may provide portfolio credit default swaps, where the counterparty is usually an investment bank.

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ASSURED GUARANTY US HOLDINGS INC.

        Assured Guaranty US Holdings Inc. was formed as a holding company to hold the shares of AGC and AG Financial Products Inc. It is a wholly owned subsidiary of Assured Guaranty and was formed under the laws of the State of Delaware in February 2004. Its principal executive offices are at 1325 Avenue of the Americas, New York, New York, and its telephone number is (212) 974-0100.


USE OF PROCEEDS

        Unless otherwise disclosed in the applicable prospectus supplement, Assured Guaranty and Assured Guaranty US Holdings intend to use the net proceeds from the sale of the offered securities for general corporate purposes, which may include repayment of indebtedness, expansion of our net underwriting capacity and acquisitions.


RATIO OF EARNINGS TO FIXED CHARGES OF ASSURED GUARANTY

        For purposes of computing the following ratios, earnings consist of net income (loss) before income tax expense, excluding interest costs capitalized, plus fixed charges to the extent that these charges are included in the determination of earnings. Fixed charges consist of interest costs, including interest costs capitalized, plus one-third of minimum rental payments under operating leases, which are estimated by management to be the interest factor of these rentals. Because the Company paid no preferred share dividends during any of the periods presented, the ratio of earnings to combined fixed charges and preferred share dividends is identical to the ratio of earnings to fixed charges for each of the periods presented.

 
  Three Months
Ended
March 31,
2009
  Fiscal year Ended December 31,  
 
  2008   2007   2006   2005   2004  

Ratio of Earnings to Fixed Charges

    16.17 x   5.46 x     (a)   13.84 x   16.83 x   20.85 x

(a)
Due to the Company's loss in the fiscal year ended December 31, 2007, the Company's fixed charges exceeded earnings by $463.0 million.


GENERAL DESCRIPTION OF THE OFFERED SECURITIES

        Assured Guaranty may, from time to time, offer under this prospectus, separately or together:

        Assured Guaranty US Holdings may, from time to time, offer unsecured senior or subordinated debt securities, which will be fully and unconditionally guaranteed by Assured Guaranty.

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DESCRIPTION OF ASSURED GUARANTY SHARE CAPITAL

        The following summary of our share capital is qualified in its entirety by the provisions of Bermuda law, our memorandum of association and Bye-Laws, copies of which are incorporated by reference to the registration statement of which this prospectus is a part. In this section, the "Company," "we," "us" and "our" refer to Assured Guaranty Ltd. and not to any of its subsidiaries.

General

        We have an authorized share capital of $5,000,000 divided into 500,000,000 shares, par value U.S. $0.01 per share, of which 90,990,867 common shares were issued and outstanding as of May 1, 2009. As of May 1, 2009, our subsidiary, Assured Guaranty US Holdings, owned 5,354,116 of our common shares. Except as described below, our common shares have no preemptive rights or other rights to subscribe for additional common shares, no rights of redemption, conversion or exchange and no sinking fund rights. In the event of liquidation, dissolution or winding-up, the holders of our common shares are entitled to share equally, in proportion to the number of common shares held by such holder, in our assets, if any remain after the payment of all our debts and liabilities and the liquidation preference of any outstanding preferred shares. Under certain circumstances, we have the right to purchase all or a portion of the shares held by a shareholder. See "—Acquisition of Common Shares by Us" below. All of the common and preferred shares being sold in this offering are fully paid and non-assessable. Holders of our common shares are entitled to receive such dividends as lawfully may be declared from time to time by our board of directors.

Voting Rights and Adjustments

        In general, and except as provided below, shareholders have one vote for each common share held by them and are entitled to vote with respect to their fully paid shares at all meetings of shareholders. However, if, and so long as, the common shares (and other of our shares) of a shareholder are treated as "controlled shares" (as determined pursuant to section 958 of the U.S. Internal Revenue Code of 1986, as amended, which we refer to in this prospectus as the Code) of any "United States person" as defined in the Code (a "U.S. Person") and such controlled shares constitute 9.5% or more of the votes conferred by our issued and outstanding shares, the voting rights with respect to the controlled shares owned by such U.S. Person shall be limited, in the aggregate, to a voting power of less than 9.5% of the voting power of all issued and outstanding shares, under a formula specified in our Bye-laws. The formula is applied repeatedly until there is no U.S. Person whose controlled shares constitute 9.5% or more of the voting power of all issued and outstanding shares and who generally would be required to recognize income with respect to us under the Code if we were a controlled foreign corporation as defined in the Code and if the ownership threshold under the Code were 9.5% (as defined in our Bye-Laws as a "9.5% U.S. Shareholder"). In addition, our board of directors may determine that shares held carry different voting rights when it deems it appropriate to do so to (i) avoid the existence of any 9.5% U.S. Shareholder; and (ii) avoid adverse tax, legal or regulatory consequences to the Company or any of its subsidiaries or any direct or indirect holder of shares or its affiliates. "Controlled shares" includes, among other things, all shares of Assured Guaranty that such U.S. Person is deemed to own directly, indirectly or constructively (within the meaning of section 958 of the Code). The foregoing provision does not apply to ACE Limited, which holds approximately 21% of our common shares as of August 1, 2008 because it is not a U.S. Person. Further, these provisions do not apply in the event one shareholder owns greater than 75% of the voting power of all issued and outstanding shares.

        Under these provisions, certain shareholders may have their voting rights limited to less than one vote per share, while other shareholders may have voting rights in excess of one vote per share. Moreover, these provisions could have the effect of reducing the votes of certain shareholders who would not otherwise be subject to the 9.5% limitation by virtue of their direct share ownership. Our Bye-laws provide that we will use our best efforts to notify shareholders of their voting interests prior to any vote to be taken by them.

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        Our board of directors is authorized to require any shareholder to provide information for purposes of determining whether any holder's voting rights are to be adjusted, which may be information on beneficial share ownership, the names of persons having beneficial ownership of the shareholder's shares, relationships with other shareholders or any other facts our board of directors may deem relevant. If any holder fails to respond to this request or submits incomplete or inaccurate information, our board of directors may eliminate the shareholder's voting rights. All information provided by the shareholder will be treated by us as confidential information and shall be used by us solely for the purpose of establishing whether any 9.5% U.S. Shareholder exists and applying the adjustments to voting power (except as otherwise required by applicable law or regulation).

Restrictions on Transfer of Common Shares

        Each transfer must comply with current Bermuda Monetary Authority permission or have specific permission from the Bermuda Monetary Authority. Our board of directors may decline to register a transfer of any common shares under certain circumstances, including if they have reason to believe that any adverse tax, regulatory or legal consequences to us, any of our subsidiaries or any of our shareholders or indirect holders of shares or its Affiliates may occur as a result of such transfer (other than such as our board of directors considers de minimis). Transfers must be by instrument unless otherwise permitted by the Companies Act 1981 of Bermuda, which we refer to in this prospectus as the Companies Act.

        The restrictions on transfer and voting restrictions described above may have the effect of delaying, deferring or preventing a change in control of Assured Guaranty.

        Before a person can acquire control of a U.S.-domiciled insurance company, prior written approval must be obtained from the insurance commissioner of the states where the insurer is domiciled or deemed commercially domiciled. Generally, state statutes provide that control over an insurer is presumed to exist if any person, directly or indirectly, owns, controls, holds with the power to vote, or holds proxies representing, 10% or more of the voting securities of the insurer. Because a person acquiring 10% or more of our common shares would indirectly control the same percentage of the stock of our U.S. insurance company subsidiaries, the insurance change of control laws of Maryland and New York would likely apply to such a transaction. Prior to granting approval of an application to acquire control of an insurer, the state insurance commissioner will consider such factors as the financial strength of the applicant, the integrity and management of the applicant's Board of Directors and executive officers, the acquirer's plans for the management of the applicant's Board of Directors and executive officers, the acquirer's plans for the future operations of the insurer and any anti-competitive results that may arise from the consummation of the acquisition of control.

        The Financial Services and Markets Act 2000 ("FSMA") regulates the acquisition of "control" of any UK insurance company authorized under FSMA. Any company or individual that (together with its or his associates) directly or indirectly acquires 10% or more of the shares in a UK authorized insurance company or its parent company, or is entitled to exercise or control the exercise of 10% or more of the voting power in such authorized insurance company or its parent company, would be considered to have acquired "control" for the purposes of the relevant legislation, as would a person who had significant influence over the management of such authorized insurance company or its parent company by virtue of his shareholding or voting power in either. Under FSMA, any person proposing to acquire "control" of a UK authorized insurance company must give prior notification to the FSA UK of its intention to do so. The Financial Services Authority ("FSA UK") then has three months to consider that person's application to acquire "control." In considering whether to approve such application, the FSA UK must be satisfied that both the acquirer is a "fit and proper" person to have "control" and that the interests of consumers would not be threatened by such acquisition of "control." "Consumers" in this context includes all persons who may use the services of the authorized insurance company. Failure to make the relevant prior application could result in action being taken by the FSA UK.

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Acquisition of Common Shares by Us

        Under our Bye-Laws and subject to Bermuda law, if our board of directors determines that any ownership of our shares may result in adverse tax, legal or regulatory consequences to us, any of our subsidiaries or any of our shareholders or indirect holders of shares or its affiliates (other than such as our board of directors considers de minimis), we have the option, but not the obligation, to require such shareholder to sell to us or to a third party to whom we assign the repurchase right the minimum number of common shares necessary to avoid or cure any such adverse consequences at a price determined in the discretion of the board of directors to represent the shares' fair market value (as defined in our Bye-Laws).

Issuance of Shares

        Subject to our Bye-Laws and Bermuda law, our board of directors has the power to issue any of our unissued shares as it determines, including the issuance of any shares or class of shares with preferred, deferred or other special rights.

Bye-Laws

        In addition to the provisions of the Bye-Laws described above under "—Voting Rights and Adjustments," the following provisions are a summary of some of the other important provisions of our Bye-Laws.

        Our Board of Directors and Corporate Action.    Our Bye-Laws provide that our board of directors shall consist of not less than three and not more than 21 directors, the exact number as determined by the board of directors. Our board of directors consists of 11 persons, and is divided into three classes. Each director generally will serve a three-year term, with termination staggered according to class. Shareholders may only remove a director for cause (as defined in our Bye-Laws) at a general meeting, provided that the notice of any such meeting convened for the purpose of removing a director shall contain a statement of the intention to do so and shall be provided to that director at least two weeks before the meeting. Vacancies on the board of directors can be filled by the board of directors if the vacancy occurs in those events set out in our Bye-Laws as a result of death, disability, disqualification or resignation of a director, or from an increase in the size of the board of directors.

        Generally under our Bye-Laws, the affirmative votes of a majority of the votes cast at any meeting at which a quorum is present is required to authorize a resolution put to vote at a meeting of the board of directors. Corporate action may also be taken by a unanimous written resolution of the board of directors without a meeting. A quorum shall be at least one-half of directors then in office present in person or represented by a duly authorized representative, provided that at least two directors are present in person.

        Shareholder Action.    At the commencement of any general meeting, two or more persons present in person and representing, in person or by proxy, more than 50% of the issued and outstanding shares entitled to vote at the meeting shall constitute a quorum for the transaction of business. In general, anything that may be done by resolution of our shareholders in a general meeting may be taken, without a meeting, by a resolution in writing signed by all of the shareholders entitled to attend such meeting and vote on the resolution. In general, any questions proposed for the consideration of the shareholders at any general meeting shall be decided by the affirmative votes of a majority of the votes cast in accordance with the Bye-Laws.

        The Bye-Laws contain advance notice requirements for shareholder proposals and nominations for directors, including when proposals and nominations must be received and the information to be included.

        Amendment.    The Bye-Laws may be amended only by a resolution adopted by the board of directors and by resolution of the shareholders.

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        Voting of Non-U.S. Subsidiary Shares.    If we are required or entitled to vote at a general meeting of any of AG Re, Assured Guaranty Finance Overseas Re or any other directly held non-U.S. subsidiary of ours, our board of directors shall refer the subject matter of the vote to our shareholders and seek direction from such shareholders as to how they should vote on the resolution proposed by the non-U.S. subsidiary. Our board of directors in its discretion shall require that substantially similar provisions are or will be contained in the bye-laws (or equivalent governing documents) of any direct or indirect non-U.S. subsidiaries other than Assured Guaranty (UK) Ltd. and Assured Guaranty Re Overseas Ltd.

Anti-Takeover Provisions in our Bye-laws

        Our Bye-Laws contain provisions that may entrench directors and make it more difficult for shareholders to replace directors even if the shareholders consider it beneficial to do so. In addition, these provisions could delay or prevent a change of control that a shareholder might consider favorable. For example, these provisions may prevent a shareholder from receiving the benefit from any premium over the market price of our common shares offered by a bidder in a potential takeover. Even in the absence of an attempt to effect a change in management or a takeover attempt, these provisions may adversely affect the prevailing market price of our common shares if they are viewed as discouraging takeover attempts in the future.

        For example, our Bye-Laws contain the following provisions that could have such an effect:

Differences in Corporate Law

        You should be aware that the Companies Act, which applies to us, differs in certain material respects from laws generally applicable to U.S. corporations and their shareholders. In order to highlight these differences, set forth below is a summary of certain significant provisions of the Companies Act applicable to us (including modifications adopted pursuant to our Bye-Laws) which differ in certain respects from provisions of the corporate law of the State of Delaware. Because the following statements are summaries, they do not address all aspects of Bermuda law that may be relevant to us and our shareholders.

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        Duties of Directors.    Under Bermuda common law, members of a board of directors owe a fiduciary duty to the company to act in good faith in their dealings with or on behalf of the company, and to exercise their powers and fulfill the duties of their office honestly. This duty has the following essential elements:

        The Companies Act imposes a duty on directors and officers of a Bermuda company:

        In addition, the Companies Act imposes various duties on officers of a company with respect to certain matters of management and administration of the company.

        The Companies Act provides that in any proceedings for negligence, default, breach of duty or breach of trust against any officer, if it appears to a court that such officer is or may be liable in respect of the negligence, default, breach of duty or breach of trust, but that he has acted honestly and reasonably, and that, having regard to all the circumstances of the case, including those connected with his appointment, he ought fairly to be excused for the negligence, default, breach of duty or breach of trust, that court may relieve him, either wholly or partly, from any liability on such terms as the court may think fit. This provision has been interpreted to apply only to actions brought by or on behalf of the company against such officers. Our Bye-Laws, however, provide that we and each of our shareholders waive all claims or rights of action that they might have, individually or in the right of the Company, against any director or officer of us (and others identified in the Bye-Laws) for any act or failure to act in the performance of such director's or officer's duties, provided that this waiver does not extend to any claims or rights of action that arise out of fraud or dishonesty on the part of such director or officer.

        Under Delaware law, the business and affairs of a corporation are managed by or under the direction of its board of directors. In exercising their powers, directors are charged with a fiduciary duty of care to protect the interests of the corporation and a fiduciary duty of loyalty to act in the best interests of its shareholders.

        The duty of care requires that directors act in an informed and deliberate manner, and inform themselves, prior to making a business decision, of all relevant material information reasonably available to them. The duty of care also requires that directors exercise care in overseeing and investigating the conduct of corporate employees. The duty of loyalty may be summarized as the duty to act in good faith, not out of self-interest, and in a manner which the director reasonably believes to be in the best interests of the shareholders.

        Under the "business judgment rule," courts generally do not second guess the business judgment of directors and officers. A party challenging the propriety of a decision of a board of directors bears the burden of rebutting the presumption afforded to directors by the business judgment rule. If the presumption is not rebutted, the business judgment rule attaches to protect the directors from liability for their decisions. Where, however, the presumption is rebutted, the directors bear the burden of demonstrating the fairness of the relevant transaction. However, when the board of directors takes defensive actions in response to a threat to corporate control and approves a transaction resulting in a sale of control of the corporation, Delaware courts subject directors' conduct to enhanced scrutiny.

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        Interested Directors.    Under Bermuda law and our Bye-Laws, a transaction entered into by us, in which a director has an interest, will not be voidable by us, and such director will not be liable to us for any profit realized pursuant to such transaction, provided the nature of the interest is duly disclosed at the first opportunity at a meeting of directors, or in writing to the directors. In addition, our Bye-Laws allow a director to be taken into account in determining whether a quorum is present and to vote on a transaction in which the director has an interest following a declaration of the interest pursuant to the Companies Act, provided that the director is not disqualified from doing so by the chairman of the meeting. Under Delaware law, such a transaction would not be voidable if

Under Delaware law, an interested director could be held liable for a transaction in which such director derived an improper personal benefit.

        Dividends.    Bermuda law does not permit the declaration or payment of dividends or distributions of contributed surplus by a company if there are reasonable grounds for believing that the company, after the payment is made, would be unable to pay its liabilities as they become due, or the realizable value of the company's assets would be less, as a result of the payment, than the aggregate of its liabilities and its issued share capital and share premium accounts. The excess of the consideration paid on issue of shares over the aggregate par value of such shares must (except in certain limited circumstances) be credited to a share premium account. Share premium may be distributed in certain limited circumstances; for example, to pay up unissued shares which may be distributed to shareholders in proportion to their holdings, but is otherwise subject to limitation. In addition, our ability to declare and pay dividends and other distributions is subject to Bermuda insurance laws and regulatory constraints.

        Under Delaware law, subject to any restrictions contained in the company's certificate of incorporation, a company may pay dividends out of surplus or, if there is no surplus, out of net profits for the fiscal year in which the dividend is declared and for the preceding fiscal year. Delaware law also provides that dividends may not be paid out of net profits at any time when capital is less than the capital represented by the outstanding stock of all classes having a preference upon the distribution of assets.

        Amalgamations, Mergers and Similar Arrangements.    The amalgamation of a Bermuda company with another company or corporation (other than certain affiliated companies) requires the amalgamation agreement to be approved by the company's board of directors and by its shareholders. We may, with the approval of our board and, except in the case of amalgamations with and between wholly owned subsidiaries being Bermuda companies, at least 75% of the votes cast at a general meeting of our shareholders at which a quorum is present, amalgamate with another Bermuda company or with a body incorporated outside Bermuda. In the case of an amalgamation, a shareholder may apply to a Bermuda court for a proper valuation of such shareholder's shares if such shareholder is not satisfied that fair market value has been paid for such shares.

        Under Delaware law, with certain exceptions, a merger, consolidation or sale of all or substantially all the assets of a corporation must be approved by the board of directors and a majority of the outstanding shares entitled to vote thereon. Under Delaware law, a shareholder of a corporation participating in certain major corporate transactions may, under certain circumstances, be entitled to appraisal rights pursuant to which such shareholder may receive payment in the amount of the fair

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market value of the shares held by such shareholder (as determined by a court) in lieu of the consideration such shareholder would otherwise receive in the transaction.

        Takeovers.    Bermuda law provides that where an offer is made for shares of a company and, within four months of the offer, the holders of not less than 90% of the shares which are the subject of the offer accept, the offeror may by notice require the non-tendering shareholders to transfer their shares on the terms of the offer. Dissenting shareholders may apply to the court within one month of the notice objecting to the transfer. The test is one of fairness to the body of the shareholders and not to individuals and the burden is on the dissentient shareholder to prove unfairness, not merely that the scheme is open to criticism. Delaware law provides that a parent corporation, by resolution of its board of directors and without any shareholder vote, may merge with any subsidiary of which it owns at least 90% of each class of capital stock. Upon any such merger, dissenting shareholders of the subsidiary would have appraisal rights.

        Certain Transactions with Significant Shareholders.    As a Bermuda company, we may enter into certain business transactions with our significant shareholders, including asset sales, in which a significant shareholder receives, or could receive, a financial benefit that is greater than that received, or to be received, by other shareholders with prior approval from our board of directors but without obtaining prior approval from our shareholders. If we were a Delaware corporation, we would need, subject to certain exceptions, prior approval from shareholders holding at least two-thirds of our outstanding common stock not owned by such interested shareholder to enter into a business combination (which, for this purpose, includes asset sales of greater than 10% of our assets that would otherwise be considered transactions in the ordinary course of business) with an interested shareholder for a period of three years from the time the person became an interested shareholder, unless we had opted out of the relevant Delaware statute, as provided for in that statute.

        Shareholders' Suits.    The rights of shareholders under Bermuda law are not as extensive as the rights of shareholders under legislation or judicial precedent in many U.S. jurisdictions. Class actions and derivative actions are generally not available to shareholders under the laws of Bermuda. However, the Bermuda courts ordinarily would be expected to follow English case law precedent, which would permit a shareholder to commence an action in our name to remedy a wrong done to us where the act complained of is alleged to be beyond our corporate power or is illegal or would result in the violation of our Memorandum of Association or Bye-Laws. Furthermore, consideration would be given by the court to acts that are alleged to constitute a fraud against the minority shareholders or where an act requires the approval of a greater percentage of our shareholders than actually approved it. The winning party in such an action generally would be able to recover a portion of attorneys' fees incurred in connection with such action. Our Bye-Laws provide that shareholders waive all claims or rights of action that they might have, individually or in the right of the Company, against any director or officer for any action or failure to act in the performance of such director's or officer's duties, except such waiver shall not extend to claims or rights of action that arise out of any fraud or dishonesty of such director or officer. Class actions and derivative actions generally are available to shareholders under Delaware law for, among other things, breach of fiduciary duty, corporate waste and actions not taken in accordance with applicable law. In such actions, the court generally has discretion to permit the winning party to recover attorneys' fees incurred in connection with such action.

        Indemnification of Directors and Officers.    Under Bermuda law we may, and under our Bye-Laws we will, indemnify our directors, officers, any other person appointed to a committee of the board of directors and certain other persons identified in the Bye-Laws (and their respective heirs, executors or administrators) against all actions, costs, charges, losses, damages and expenses incurred or sustained by such person by reason of any act done, concurred in or omitted in the execution of his/her duties or supposed duties; provided that such indemnification shall not extend to any matter involving any fraud or dishonesty on the part of such director, officer or other person. Under Delaware law, a corporation may indemnify a director or officer of the corporation against expenses (including attorneys' fees),

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judgments, fines and amounts paid in settlement actually and reasonably incurred in defense of an action, suit or proceeding by reason of such position if

Under our Bye-Laws, we and each of our shareholders agree to waive any claim or right of action, other than those involving fraud or dishonesty, against any of our officers or directors or others identified in our Bye-Laws.

        Inspection of Corporate Records.    Members of the general public have the right to inspect our public documents available at the office of the Registrar of Companies in Bermuda and our registered office in Bermuda, which will include our memorandum of association (including its objects and powers) and any alteration to our memorandum of association and documents relating to any increase or reduction of authorized capital. Our shareholders have the additional right to inspect our Bye-Laws, minutes of general meetings and audited annual financial statements, which must be presented to the annual general meeting of shareholders. The register of our shareholders is also open to inspection by shareholders and members of the public without charge. We are required to maintain our share register in Bermuda but, after our shares are listed on the New York Stock Exchange and giving the required notice to the Bermuda Registrar of Companies, we may establish a branch register outside of Bermuda. We are required to keep at our registered office a register of our directors and officers (containing that information required under Bermuda law) which is open for inspection by members of the public without charge. Bermuda law does not, however, provide a general right for shareholders to inspect or obtain copies of any other corporate records. Delaware law permits any shareholder to inspect or obtain copies of a corporation's shareholder list and its other books and records for any purpose reasonably related to such person's interest as a shareholder.

        Shareholder Proposals.    Under Bermuda law, the Companies Act provides that shareholders may, as set forth below and at their own expense (unless a company otherwise resolves), require a company to give notice of any resolution that the shareholders can properly propose at the next annual general meeting and/or to circulate a statement prepared by the requesting shareholders in respect of any matter referred to in a proposed resolution or any business to be conducted at a general meeting. The number of shareholders necessary for such a requisition is either that number of shareholders representing at least 5% of the total voting rights of all shareholders having a right to vote at the meeting to which the requisition relates or not less than 100 shareholders. Our Bye-Laws also include advance-notice provisions regarding shareholder proposals and nominations. Delaware law does not include a provision restricting the manner in which nominations for directors may be made by shareholders or the manner in which business may be brought before a meeting.

        Calling of Special Shareholders' Meetings.    Under our Bye-Laws, a special general meeting may be called by our President or by our Chairman or any director and the secretary of the Company or our board of directors. Under Bermuda law, a special meeting may also be called by the shareholders when requisitioned by the holders of at least 10% of the paid-up voting share capital of the Company as provided by the Companies Act. Delaware law permits the board of directors or any person who is authorized under a corporation's certificate of incorporation or bylaws to call a special meeting of shareholders.

        Approval of Corporate Matters by Written Consent.    Under Bermuda law, the Companies Act provides that shareholders may take action by written consent with 100% shareholders consent required. Delaware law permits shareholders to take action by the consent in writing by the holders of outstanding stock having not less than the minimum number of votes that would be necessary to

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authorize or take such action at a meeting of shareholders at which all shares entitled to vote thereon were present and voted.

        Amendment of Memorandum of Association.    Bermuda law provides that the memorandum of association of a company may be amended by a resolution passed at a general meeting of shareholders of which due notice has been given. An amendment to the memorandum of association that alters a company's business objects may require approval of the Bermuda Minister of Finance, who may grant or withhold approval at his or her discretion.

        Under Bermuda law, the holders of an aggregate of not less than 20% in par value of a company's issued share capital have the right to apply to the Bermuda courts for an annulment of any amendment of the memorandum of association adopted by shareholders at any general meeting, other than an amendment which alters or reduces a company's share capital as provided in the Companies Act. Where such an application is made, the amendment becomes effective only to the extent that it is confirmed by the Bermuda court. An application for an annulment of an amendment of the memorandum of association must be made within 21 days after the date on which the resolution altering the company's memorandum of association is passed and may be made on behalf of persons entitled to make the application by one or more of their designees as such holders may appoint in writing for such purpose. No application may be made by the shareholders voting in favor of the amendment.

        Under Delaware law, amendment of the certificate of incorporation, which is the equivalent of a memorandum of association, of a company must be made by a resolution of the board of directors setting forth the amendment, declaring its advisability, and either calling a special meeting of the shareholders entitled to vote or directing that the amendment proposed be considered at the next annual meeting of the shareholders. Delaware law requires that, unless a different percentage is provided for in the certificate of incorporation, a majority of the outstanding shares entitled to vote thereon is required to approve the amendment of the certificate of incorporation at the shareholders meeting. If the amendment would alter the number of authorized shares or otherwise adversely affect the rights or preference of any class of a company's stock, Delaware law provides that the holders of the outstanding shares of such affected class should be entitled to vote as a class upon the proposed amendment, regardless of whether such holders are entitled to vote by the certificate of incorporation. However, the number of authorized shares of any class may be increased or decreased, to the extent not falling below the number of shares then outstanding, by the affirmative vote of the holders of a majority of the stock entitled to vote, if so provided in the company's certificate of incorporation or any amendment that created such class or was adopted prior to the issuance of such class or that was authorized by the affirmative vote of the holders of a majority of such class of stock.

        Amendment of Bye-Laws.    Consistent with the Companies Act, the Company's Bye-Laws provide that the Bye-Laws may only be rescinded, altered or amended upon approval by a resolution of our board of directors and by a resolution of our shareholders.

        Under Delaware law, holders of a majority of the voting power of a corporation and, if so provided in the certificate of incorporation, the directors of the corporation, have the power to adopt, amend and repeal the bylaws of a corporation.

        Staggered Board of Directors.    Under Bermuda law, the Companies Act does not contain statutory provisions specifically mandating staggered board arrangements for a Bermuda exempted company. Such provisions, however, may validly be provided for in the Bye-Laws governing the affairs of such a company. Delaware law permits corporations to have a staggered board of directors.

Listing

        Our common shares are listed on the New York Stock Exchange under the trading symbol "AGO."

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Transfer Agent and Registrar

        The transfer agent and registrar for our common shares is BNY Mellon Shareowner Services whose principal executive office is located at 101 Barclay Street, New York NY 10286.


DESCRIPTION OF THE DEPOSITARY SHARES

General

        We may offer depositary shares, each representing a specified fraction of a share of a particular series of preferred shares. Depositary receipts evidencing depositary shares will be issued to those persons purchasing the fractional shares of the related preferred shares.

        The shares of any class or series of preferred shares represented by depositary shares will be deposited under a deposit agreement among Assured Guaranty, a depositary selected by Assured Guaranty and the holders of the depositary receipts, whom we refer to in this section as owners. Subject to the terms of the deposit agreement, each owner will be entitled to all the rights and preferences of the preferred shares represented by the depositary share in proportion to the fraction of a preferred share represented by the depositary share, including dividend, voting, redemption and liquidation rights.

Dividends and Other Distributions

        The depositary will distribute all cash dividends or other distributions received on the related preferred shares to the owners in proportion to the number of depositary shares owned. In the event of a distribution other than in cash, the depositary will distribute property received by it to the owners, unless the depositary determines that it is not feasible to make the distribution, in which case the depositary may, with our approval, sell the property and distribute the net proceeds from the sale to the owners.

Withdrawal of Shares

        Upon surrender of the depositary receipts, unless the related depositary shares have previously been called for redemption, the owner is entitled to delivery of the number of whole shares of the related preferred shares and any money or other property represented by his depositary shares. Holders of the whole preferred shares will not be entitled to exchange the preferred shares for depositary shares. If the delivered depositary receipts evidence a number of depositary shares in excess of the number of whole preferred shares to be withdrawn, the depositary will deliver to the owner a new depositary receipt evidencing this excess number at the same time. In no event will fractional preferred shares be delivered upon surrender of depositary receipts.

Redemption of Depositary Shares

        Whenever we redeem preferred shares held by the depositary, the depositary will redeem the number of depositary shares representing the related preferred shares. The redemption price per depositary share will be equal to the applicable fraction of the redemption price per preferred share. If less than all the depositary shares are to be redeemed, the depositary shares to be redeemed will be selected by lot or pro rata as may be determined by the depositary or us.

Voting the Preferred Shares

        Upon receipt of notice of any meeting at which the holders of the preferred shares are entitled to vote, the depositary will mail the information contained in the notice to the record owners of the depositary shares. Each record owner on the record date, which will be the same as the record date for the preferred shares, may instruct the depositary how to exercise its voting rights pertaining to the preferred shares represented by the owner's depositary shares. The depositary will endeavor, insofar as practicable, to vote the number of the preferred shares represented by these depositary shares in

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accordance with the instructions, and we will agree to take all action which the depositary deems necessary in order to enable the depositary to do so. The depositary will not vote preferred shares if it does not receive specific instructions from the record owners.

Amendment and Termination of the Deposit Agreement

        Unless otherwise provided in the applicable prospectus supplement, the form of depositary receipt and any provision of the deposit agreement may be amended at any time by agreement between us and the depositary. However, any amendment which materially and adversely alters the rights of the owners will not be effective unless it has been approved by the owners representing at least a majority, or, in the case of amendments affecting rights to receive dividends or distributions or voting or redemption rights, 662/3% of the depositary shares then outstanding. We or the depositary may terminate the deposit agreement only:

Charges of Depositary

        We will pay all transfer and other taxes and governmental charges arising solely from the existence of the depositary arrangements. We will also pay charges of the depositary in connection with the initial deposit of preferred shares and any redemption of the preferred shares. Owners will pay all other transfer and other taxes and governmental charges and any other charges as are expressly provided in the deposit agreement to be for their accounts.

        The depositary may refuse to transfer a depositary receipt or any withdrawal of preferred shares evidenced by the depositary receipts until all taxes and charges with respect to the receipts or preferred shares are paid by the owners.

Miscellaneous

        The depositary will forward all reports and communications which it receives from us and which we are required to furnish to the holders of the preferred shares.

        Neither the depositary nor we will be liable if the depositary is prevented or delayed by law or any circumstance beyond its control in performing its obligations under the deposit agreement. Our and the depositary's obligations will be limited to performance of the duties under the deposit agreement in a manner that does not constitute bad faith, and neither we nor the depositary will be obligated to prosecute or defend any legal proceeding in respect of any depositary or preferred shares unless satisfactory indemnity is furnished.

Resignation and Removal of Depositary

        The depositary may resign at any time by delivering to us notice of its election to resign, and we may at any time remove the depositary. Any resignation or removal of the depositary will take effect upon the appointment of a successor depositary, which successor depositary must be appointed within 60 days after delivery of the notice of resignation or removal and must be a bank or trust company having its principal office in the United States and having a combined capital and surplus of at least $50,000,000 or be an affiliate of such bank or trust company.

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DESCRIPTION OF THE ASSURED GUARANTY DEBT SECURITIES

        The following description of the Assured Guaranty debt securities sets forth the material terms and provisions of the Assured Guaranty debt securities. The Assured Guaranty senior debt securities will be issued under an indenture, referred to in this prospectus as the Assured Guaranty senior indenture, between us and The Bank of New York, as trustee, the form of which is incorporated by reference as an exhibit to the registration statement of which this prospectus forms a part. The Assured Guaranty subordinated debt securities will be issued under an indenture, referred to in this prospectus as the Assured Guaranty subordinated indenture, between us and The Bank of New York, as trustee, the form of which is incorporated by reference as an exhibit to the registration statement of which this prospectus forms a part. The Assured Guaranty senior indenture and the Assured Guaranty subordinated indenture are sometimes referred to in this prospectus collectively as the Assured Guaranty indentures and each individually as an Assured Guaranty indenture. The specific terms applicable to a particular issuance of Assured Guaranty debt securities and any variations from the terms set forth below will be set forth in the applicable prospectus supplement.

        The following is a summary of the material terms and provisions of the Assured Guaranty indentures and the Assured Guaranty debt securities. You should refer to the forms of the Assured Guaranty indentures and the Assured Guaranty debt securities for complete information regarding the terms and provisions of the Assured Guaranty indentures and the Assured Guaranty debt securities. The Assured Guaranty indentures are substantially identical, except for the covenants of Assured Guaranty and provisions relating to subordination.

General

        The Assured Guaranty indentures do not limit the aggregate principal amount of Assured Guaranty debt securities which we may issue. We may issue Assured Guaranty debt securities under the Assured Guaranty indentures from time to time in one or more series. The Assured Guaranty indentures do not limit the amount of other indebtedness, or Assured Guaranty debt securities other than secured indebtedness, which we or our subsidiaries may issue.

        Unless otherwise provided in a prospectus supplement, the Assured Guaranty senior debt securities will be our unsecured obligations and will rank equally with all of our other unsecured and unsubordinated indebtedness. The Assured Guaranty subordinated debt securities will be our unsecured obligations and will be subordinated in right of payment to the prior payment in full of all of our senior indebtedness, which term includes Assured Guaranty senior debt securities, as described below under "Subordination of Assured Guaranty Subordinated Debt Securities."

        Because we are a holding company, our rights and the rights of our creditors, including you, as a holder of Assured Guaranty debt securities, and shareholders to participate in any distribution of assets of any subsidiary upon the subsidiary's liquidation or reorganization or otherwise would be subject to the prior claims of the subsidiary's creditors, except to the extent that we are a creditor of the subsidiary. The right of our creditors, including you, to participate in the distribution of stock owned by us in some of our subsidiaries, including our insurance subsidiaries, may also be subject to approval by insurance regulatory authorities having jurisdiction over these subsidiaries.

        Each prospectus supplement will describe the following terms of the offered Assured Guaranty debt securities:

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        We will have the ability under the Assured Guaranty indentures to "reopen" a previously issued series of Assured Guaranty debt securities and issue additional Assured Guaranty debt securities of that series or establish additional terms of that series. We are also permitted to issue Assured Guaranty debt securities with the same terms as previously issued Assured Guaranty debt securities.

        Unless otherwise set forth in the applicable prospectus supplement, principal of, premium and interest on and additional amounts, if any, on the Assured Guaranty debt securities will initially be payable at the corporate trust office of the trustee or any other office or agency designated by us. Interest on Assured Guaranty debt securities issued in registered form:

        We will designate the initial paying agents, which will be named in the applicable prospectus supplement, and may, at any time, designate additional paying agents, rescind the designation of any paying agent or approve a change in the office through which any paying agent acts. However, we are required to maintain a paying agent in each place where the principal of, any premium or interest on or any additional amounts with respect to the Assured Guaranty debt securities are payable.

        Unless otherwise set forth in the applicable prospectus supplement, you may present the Assured Guaranty debt securities for transfer, duly endorsed or accompanied by a written instrument of transfer if so required by Assured Guaranty or the security registrar, or exchange for other Assured Guaranty debt securities of the same series containing identical terms and provisions, in any authorized denominations, and of a like aggregate principal amount, in each case at the office or agency

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maintained by us for this purpose, which will initially be the corporate trust office of the trustee. Any transfer or exchange will be made without service charge, although we may require payment of a sum sufficient to cover any tax or other governmental charge and any other expenses then payable. Assured Guaranty is not required to:

        Unless otherwise set forth in the applicable prospectus supplement, we will only issue the Assured Guaranty debt securities in fully registered form without coupons in minimum denominations of $1,000 and any integral multiple of $1,000. If the Assured Guaranty debt securities are issued in bearer form, any restrictions and considerations, including offering restrictions and U.S. federal income tax considerations applicable to these securities and to payment on and transfer and exchange of these securities, will be described in the applicable prospectus supplement.

        The Assured Guaranty debt securities may be issued as original issue discount securities, which means that they will bear no interest or bear interest at a rate which, at the time of issuance, is below market rates. Assured Guaranty debt securities issued as original issue discount securities will be sold at a substantial discount below their principal amount.

        U.S. Federal income tax and other considerations applicable to original issue discount securities will be described in the applicable prospectus supplement.

        If the purchase price, or the principal of, or any premium or interest on, or any additional amounts with respect to, any Assured Guaranty debt securities is payable in, or if any Assured Guaranty debt securities are denominated in, one or more foreign currencies or currency units, the restrictions, elections, U.S. Federal income tax considerations, specific terms and other information will be set forth in the applicable prospectus supplement.

        Unless otherwise set forth in the applicable prospectus supplement, other than as described below under "—Covenants Applicable to Assured Guaranty Senior Debt Securities—Limitation on Liens on Stock of Designated Subsidiaries," the Assured Guaranty indentures do not limit our ability to incur indebtedness or protect holders of the Assured Guaranty debt securities in the event of a sudden and significant decline in our credit quality or a takeover, recapitalization or highly leveraged or similar transaction involving us. Accordingly, we could in the future enter into transactions that could increase the amount of its outstanding indebtedness or otherwise affect its capital structure or credit rating.

Conversion and Exchange

        The terms, if any, on which Assured Guaranty debt securities are convertible into or exchangeable for, either mandatorily or at our or your option, property or cash, common shares, preferred shares or other securities, whether or not issued by us, or a combination of any of these, will be set forth in the applicable prospectus supplement.

Global Securities

        The Assured Guaranty debt securities may be issued, in whole or in part, in the form of one or more global securities that will be deposited with, or on behalf of, a depositary identified in the applicable prospectus supplement and registered in the name of the depositary or its nominee. Interests

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in any global Assured Guaranty debt security will be shown on, and transfers of the Assured Guaranty debt securities will be effected only through, records maintained by the depositary and its participants as described below.

        The specific terms of the depositary arrangement will be described in the applicable prospectus supplement.

Payment of Additional Amounts

        We will make all payments on the Assured Guaranty debt securities without withholding of any present or future taxes or governmental charges of Bermuda, referred to as a taxing jurisdiction, unless we are required to do so by applicable law or regulation.

        If we are required to withhold amounts, we will, subject to the limitations described below, pay to you additional amounts so that every net payment made to you, after the withholding, will be the same amount provided for in the Assured Guaranty debt security and the applicable Assured Guaranty indenture.

        We will not be required to pay any additional amounts for:

        In addition, we will not pay additional amounts if you are a fiduciary or partnership or other than the sole beneficial owner of the Assured Guaranty debt security if the beneficiary or partner or settlor would not have been entitled to the additional amounts had it been the holder of the Assured Guaranty debt security.

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Covenants Applicable to Assured Guaranty Senior Debt Securities

        Under the Assured Guaranty senior indenture, we will covenant that, so long as any Assured Guaranty senior debt securities are outstanding, we will not, nor will we permit any subsidiary to, create, incur, assume or guarantee or otherwise permit to exist any indebtedness secured by any security interest on any shares of capital stock of any designated subsidiary, unless we concurrently provide that the Assured Guaranty senior debt securities and, if we elect, any other indebtedness that is not subordinate to the Assured Guaranty senior debt securities and with respect to which the governing instruments require, or pursuant to which we are obligated, to provide such security, will be secured equally with this indebtedness for at least the time period this other indebtedness is so secured.

        The term "designated subsidiary" means any present or future consolidated subsidiary, the consolidated net worth of which constitutes at least 5% of our consolidated net worth.

        For purposes of the Assured Guaranty indentures, the term "indebtedness" means, with respect to any person:

        The Assured Guaranty senior indenture also provides that, so long as any Assured Guaranty senior debt securities are outstanding and except in a transaction otherwise governed by the Assured Guaranty indentures, we will not issue, sell, assign, transfer or otherwise dispose of any shares of securities convertible into, or warrants, rights or options to subscribe for or purchase shares of, capital stock, other than preferred stock having no voting rights, of any designated subsidiary. Similarly, we will not permit any designated subsidiary to issue, other than to us, these types of securities, warrants, rights or

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options, other than director's qualifying shares and preferred stock having no voting rights, of any designated subsidiary, if, after giving effect to the transaction and the issuance of the maximum number of shares issuable upon the conversion or exercise of all the convertible securities, warrants, rights or options, we would own, directly or indirectly, less than 80% of the shares of capital stock of the designated subsidiary, other than preferred stock having no voting rights.

        However, we may issue, sell, assign, transfer or otherwise dispose of securities if the consideration is at least a fair market value as determined by our board or if required by law or regulation. We may also merge or consolidate any designated subsidiary into or with another direct or indirect subsidiary, the shares of capital stock of which we own at least 80% or, subject to the provisions described under"—Consolidation, Amalgamation, Merger and Sale of Assets" below, sell, transfer or otherwise dispose of the entire capital stock of any designated subsidiary at one time if the consideration is at least fair market value as determined by our board.

Consolidation, Amalgamation, Merger and Sale of Assets

        Each Assured Guaranty indenture provides that we may not:

        unless:

Events of Default

        Each of the following events will constitute an event of default under each Assured Guaranty indenture:

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        If an event of default with respect to the Assured Guaranty debt securities of any series, other than events of bankruptcy, insolvency or reorganization, occurs and is continuing, either the trustee or the holders of not less than 25% in principal amount of the outstanding Assured Guaranty debt securities of the series may declare the principal amount, or a lesser amount as may be provided for in the Assured Guaranty debt securities, of all outstanding Assured Guaranty debt securities of the series to be immediately due and payable by written notice. At any time after a declaration of acceleration has been made, but before a judgment or decree for payment of money has been obtained by the trustee, generally, the holders of not less than a majority in principal amount of the Assured Guaranty debt securities of the series may rescind and annul the declaration of acceleration. Any event of bankruptcy, insolvency or reorganization will cause the principal amount and accrued interest, or the lesser amount as provided for in the Assured Guaranty debt securities, to become immediately due and payable without any declaration or other act by the trustee or any holder.

        In connection with the issuance of any debt securities, the supplemental indenture shall provide that notwithstanding the foregoing, at Assured Guaranty's election, the sole remedy for the failure by Assured Guaranty to comply with the covenant in the indenture requiring Assured Guaranty to file with the trustee copies of the reports and other information it files with the SEC ("Assured Guaranty's SEC filing obligations") and for any failure by Assured Guaranty to comply with the requirements of Section 314(a)(1) of the TIA, which similarly requires Assured Guaranty to file with the trustee copies of the reports and other information it files with the SEC, shall, for the first 270 days after the occurrence of such failure consist exclusively of the right to receive additional interest on the debt securities of such series at an annual rate equal to 0.25% of the principal amount of the debt securities. This additional interest will accrue on the debt securities from and including the date on which a failure to comply with Assured Guaranty's SEC filing obligations or the failure to comply with the requirements of Section 314(a)(1) of the TIA first occurs to but not including the 270th day thereafter (or such earlier date on which such failure shall have been cured or waived). On such 270th day (or earlier, if such failure is cured or waived prior to such 270th day), such additional interest will cease to accrue and, if such failure has not been cured or waived prior to such 270th day, then either the trustee or the holders of not less than 25% in the aggregate principal amount of the debt securities of such

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series then outstanding may declare the principal of all the debt securities of such series, together with accrued interest, to be due and payable immediately. However, prior to such 270th day, any such failure shall not be an event of default. This provision shall not affect the rights of holders in the event of the occurrence of any other event of default.

        Each Assured Guaranty indenture provides that, within 90 days after the occurrence of any event which is, or after notice or lapse of time or both would become, an event of default the trustee will transmit notice of the default to each holder of the Assured Guaranty debt securities unless the default has been cured or waived. However, except in the case of a default in the payment of principal of, or premium, or interest, if any, on or additional amounts or any sinking fund or purchase fund installment with respect to any Assured Guaranty debt security, the trustee may withhold this notice if and so long as the board of directors, executive committee or trust committee of directors and/or responsible officers of the trustee determines in good faith that the withholding of the notice is in the best interest of the holders.

        If an event of default occurs and is continuing with respect to the Assured Guaranty debt securities of any series, the trustee may, in its discretion, proceed to protect and enforce its rights and the rights of the holders of Assured Guaranty debt securities by all appropriate judicial proceedings. Each Assured Guaranty indenture provides that, subject to the duty of the trustee during any default to act with the required standard of care, the trustee will be under no obligation to exercise any of its rights or powers under the Assured Guaranty indenture at the request or direction of any of the holders, unless the holders have offered the trustee reasonable indemnity. Subject to these indemnification provisions, the holders of a majority in principal amount of the outstanding Assured Guaranty debt securities of any series will generally have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the Assured Guaranty debt securities of the series.

Modification and Waiver

        Assured Guaranty and the trustee may modify or amend either Assured Guaranty indenture with the consent of the holders of not less than a majority in principal amount of the outstanding Assured Guaranty debt securities of each series affected by the modification or amendment, so long as the modification or amendment does not, without the consent of each affected holder:

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        In addition, no supplemental indenture may, directly or indirectly, modify or eliminate the subordination provisions of the Assured Guaranty subordinated indenture in any manner that might terminate or impair the subordination of the Assured Guaranty subordinated debt securities of any series to senior indebtedness without the prior written consent of the holders of the senior indebtedness.

        Assured Guaranty and the trustee may modify or amend the Assured Guaranty indenture and the Assured Guaranty debt securities of any series without the consent of any holder in order to, among other things:

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        The holders of at least a majority in principal amount of the outstanding Assured Guaranty debt securities of any series may, on behalf of the holders of all Assured Guaranty debt securities of that series, waive compliance by Assured Guaranty with specified covenants. The holders of not less than a majority in principal amount of the outstanding Assured Guaranty debt securities of any series may, on behalf of the holders of all Assured Guaranty debt securities of that series, waive any past default and its consequences with respect to the Assured Guaranty debt securities of that series, except a default:

        Under each Assured Guaranty indenture, Assured Guaranty must annually furnish the trustee with a statement regarding its performance of specified obligations and any default in its performance under the applicable Assured Guaranty indenture. Assured Guaranty is also required to deliver to the trustee, within five days after its occurrence, written notice of any event of default, or any event which after notice or lapse of time or both would constitute an event of default, resulting from the failure to perform, or breach of, any covenant or warranty contained in the applicable Assured Guaranty indenture or the Assured Guaranty debt securities.

Discharge, Defeasance and Covenant Defeasance

        We may discharge our payment obligations on the Assured Guaranty debt securities, which we refer to as defeasance, or elect to be discharged from complying with the covenants in the Assured Guaranty indentures, except for certain ministerial obligations, like registering transfers or exchanges of the Assured Guaranty debt securities, which we refer to as covenant defeasance.

        Defeasance or covenant defeasance, as the case may be, will be conditioned upon the irrevocable deposit by us with the trustee, in trust, of a cash amount or government obligations, or both, which, through the scheduled payment of principal and interest in accordance with their terms, will provide money in an amount sufficient to pay the principal of, any premium and interest on and any additional amounts with respect to, the Assured Guaranty debt securities on the scheduled due dates.

        We may only do this if, among other things:

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Subordination of Assured Guaranty Subordinated Debt Securities

        The Assured Guaranty subordinated debt securities will generally be subordinate in right of payment to the prior payment in full of all senior indebtedness. Upon any payment or distribution of our assets, whether in cash, property or securities, to creditors upon our dissolution, winding-up, liquidation or reorganization, whether voluntary or involuntary, or in bankruptcy, insolvency, receivership or other proceedings, all amounts due upon all senior indebtedness will first be paid in full, or payment provided for in money in accordance with its terms, before the holders of Assured Guaranty subordinated debt securities are entitled to receive or retain any payment on account of principal of, or any premium or interest on or any additional amounts with respect to the Assured Guaranty subordinated debt securities. This means that the holders of senior indebtedness will be entitled to receive any payment or distribution of any kind or character, including any payment or distribution which may be payable or deliverable by reason of the payment of any other indebtedness of Assured Guaranty being subordinated to the payment of Assured Guaranty subordinated debt securities, which may be payable or deliverable in respect of the Assured Guaranty subordinated debt securities upon any dissolution, winding-up, liquidation or reorganization or in any bankruptcy, insolvency, receivership or other proceeding.

        By reason of subordination, in the event of our liquidation or insolvency, holders of our senior indebtedness and holders of our other obligations that are not subordinated to senior indebtedness may recover more ratably than the holders of the Assured Guaranty subordinated debt securities.

        Subject to the payment in full of all senior indebtedness, your rights, as a holder of the Assured Guaranty subordinated debt securities, will be subrogated to the rights of the holders of senior indebtedness to receive payments or distributions of our cash, property or securities applicable to the senior indebtedness until the principal of, any premium and interest on and any additional amounts with respect to the Assured Guaranty senior debt securities have been paid in full.

        No payment of principal of, including redemption and sinking fund payments, or any premium or interest on or any additional amounts with respect to the Assured Guaranty subordinated debt securities of any series may be made:

        The Assured Guaranty subordinated indenture does not limit or prohibit us from incurring additional senior indebtedness, which may include indebtedness that is senior to the Assured Guaranty subordinated debt securities but subordinate to our other obligations. The Assured Guaranty senior debt securities will constitute senior indebtedness with respect to the Assured Guaranty subordinated debt securities.

        The term "senior indebtedness" means all indebtedness of Assured Guaranty outstanding at any time, except:

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        Senior indebtedness will continue to be senior indebtedness and be entitled to the benefits of the subordination provisions irrespective of any amendment, modification or waiver of any term of the senior indebtedness.

        The Assured Guaranty subordinated indenture provides that these subordination provisions may be changed prior to issuance of the Assured Guaranty subordinated debt securities. Any change would be described in the applicable prospectus supplement.

New York Law to Govern

        The Assured Guaranty indentures and the Assured Guaranty debt securities will be governed by, and construed in accordance with, the laws of the state of New York.

Information Concerning the Trustee

        We may, from time to time, borrow from or maintain deposit accounts and conduct other banking transactions with The Bank of New York and its affiliates in the ordinary course of business.

        Under each Assured Guaranty indenture, The Bank of New York is required to transmit annual reports to all holders regarding its eligibility and qualifications as trustee under the applicable Assured Guaranty indenture and related matters.


DESCRIPTION OF THE ASSURED GUARANTY US HOLDINGS DEBT SECURITIES
AND ASSURED GUARANTY GUARANTEE

        The following description of the Assured Guaranty US Holdings debt securities and the Assured Guaranty guarantee sets forth the material terms and provisions of the Assured Guaranty US Holdings debt securities and the Assured Guaranty guarantee to which any prospectus supplement may relate. The Assured Guaranty US Holdings senior debt securities are to be issued under an indenture, referred to in this prospectus as the Assured Guaranty US Holdings senior indenture, among Assured Guaranty US Holdings, Assured Guaranty, as guarantor, and The Bank of New York, as trustee, dated as of May 1, 2004, which is incorporated by reference as an exhibit to the registration statement of which this prospectus forms a part. The Assured Guaranty US Holdings subordinated debt securities are to be issued under an indenture, referred to in this prospectus as the Assured Guaranty US Holdings subordinated indenture, among Assured Guaranty US Holdings, Assured Guaranty, as guarantor, and The Bank of New York, as trustee, dated as of December 1, 2006, which is incorporated by reference as an exhibit to the registration statement of which this prospectus forms a part. The Assured Guaranty US Holdings senior indenture and the Assured Guaranty US Holdings subordinated indenture are sometimes referred to herein collectively as the Assured Guaranty US Holdings indentures and each individually as an Assured Guaranty US Holdings indenture. The specific terms applicable to a particular issuance of Assured Guaranty US Holdings debt securities and any variations from the terms set forth below will be set forth in the applicable prospectus supplement.

        The following is a summary of the material terms and provisions of the Assured Guaranty US Holdings indentures, the Assured Guaranty US Holdings debt securities and the Assured Guaranty guarantee. You should refer to the Assured Guaranty US Holdings indentures and the Assured Guaranty US Holdings debt securities for complete information regarding the terms and provisions of

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the Assured Guaranty US Holdings indentures, the Assured Guaranty US Holdings debt securities and the Assured Guaranty guarantee. The Assured Guaranty US Holdings indentures are substantially identical, except for the covenants of Assured Guaranty US Holdings and Assured Guaranty and provisions relating to subordination.

General

        The Assured Guaranty US Holdings indentures do not limit the aggregate principal amount of Assured Guaranty US Holdings debt securities which Assured Guaranty US Holdings may issue. Assured Guaranty US Holdings may issue Assured Guaranty US Holdings debt securities under the Assured Guaranty US Holdings indentures from time to time in one or more series. The Assured Guaranty US Holdings indentures do not limit the amount of other indebtedness or Assured Guaranty US Holdings debt securities, other than secured indebtedness which we, Assured Guaranty US Holdings or their respective subsidiaries may issue.

        Unless otherwise set forth in the applicable prospectus supplement, the Assured Guaranty US Holdings senior debt securities will be unsecured obligations of Assured Guaranty US Holdings and will rank equally with all of its other unsecured and unsubordinated indebtedness, subordinated in right of payment to the prior payment in full of all of Assured Guaranty US Holdings senior indebtedness, which term includes Assured Guaranty US Holdings senior debt securities, as described below under "Subordination of Assured Guaranty US Holdings Subordinated Debt Securities."

        Because Assured Guaranty US Holdings is a holding company, its rights and the rights of its creditors, including you as a holder of Assured Guaranty US Holdings debt securities, to participate in any distribution of assets of any subsidiary upon that subsidiary's liquidation or reorganization or otherwise would be subject to the prior claims of the subsidiary's creditors, except to the extent that Assured Guaranty US Holdings is a creditor of the subsidiary. The rights of creditors of Assured Guaranty US Holdings, including you as a holder of Assured Guaranty US Holdings debt securities, to participate in the distribution of stock owned by Assured Guaranty US Holdings in its subsidiaries, including Assured Guaranty US Holdings' insurance subsidiaries, may also be subject to the approval of insurance regulatory authorities having jurisdiction over the subsidiaries.

        The applicable prospectus supplement will describe the following terms of the offered Assured Guaranty US Holdings debt securities:

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        Assured Guaranty US Holdings has the ability under the Assured Guaranty US Holdings indentures to reopen a previously issued series of Assured Guaranty US Holdings debt securities and issue additional Assured Guaranty US Holdings debt securities of that series or establish additional terms of that series. Assured Guaranty US Holdings is also permitted to issue Assured Guaranty US Holdings debt securities with the same terms as previously issued Assured Guaranty US Holdings debt securities.

        Unless otherwise set forth in the applicable prospectus supplement, principal of, premium and interest on and additional amounts, if any, on the Assured Guaranty US Holdings debt securities will initially be payable at the corporate trust office of the trustee, or any other office or agency designated by Assured Guaranty US Holdings for this purpose. Interest on Assured Guaranty US Holdings debt securities issued in registered form:

        Assured Guaranty US Holdings will designate the initial paying agents, which will be named in the applicable prospectus supplement, and may, at any time, designate additional paying agents or rescind the designation of any paying agent or approve a change in the office through which any paying agent acts. However, Assured Guaranty US Holdings is required to maintain a paying agent in each place where the principal of, any premium or interest on or any additional amounts with respect to the Assured Guaranty US Holdings debt securities are payable.

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        Unless otherwise set forth in the applicable prospectus supplement, you may present the Assured Guaranty US Holdings debt securities for transfer, duly endorsed or accompanied by a written instrument of transfer if so required by Assured Guaranty US Holdings or the security registrar, or exchange for other Assured Guaranty US Holdings debt securities of the same series containing identical terms and provisions, in any authorized denominations, and of a like aggregate principal amount, in each case at the office or agency maintained by Assured Guaranty US Holdings for these purposes. This office will initially be the corporate trust office of the trustee. Any transfer or exchange will be made without service charge, although Assured Guaranty US Holdings may require payment of a sum sufficient to cover any tax or other governmental charge and any other expenses then payable. Assured Guaranty US Holdings is not required to:

        Assured Guaranty US Holdings has appointed the trustee as security registrar. The security registrar and any transfer agent initially designated by Assured Guaranty US Holdings will be named in the applicable prospectus supplement. At any time, Assured Guaranty US Holdings may designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts. However, Assured Guaranty US Holdings is required to maintain a transfer agent in each place where the principal of, any premium or interest on or any additional amounts with respect to the Assured Guaranty US Holdings debt securities are payable.

        Unless otherwise set forth in the applicable prospectus supplement, we will only issue the Assured Guaranty US Holdings debt securities in fully registered form without coupons in minimum denominations of $1,000 and any integral multiple of $1,000. If the Assured Guaranty US Holdings debt securities are issued in bearer form, any restrictions and considerations, including offering restrictions and U.S. federal income tax considerations applicable to, and to payment on and transfer and exchange of, these securities, will be described in the applicable prospectus supplement.

        The Assured Guaranty US Holdings debt securities may be issued as original issue discount securities, which means that they will bear no interest or bear interest at a rate which, at the time of issuance, is below market rates. Assured Guaranty US Holdings debt securities issued as original issue discount securities will be sold at a substantial discount below their principal amount. U.S. federal income tax and other considerations applicable to original issue discount securities will be described in the applicable prospectus supplement.

        If the purchase price, or the principal of, any premium or interest on or any additional amounts with respect to, any Assured Guaranty US Holdings debt securities is payable, or if any Assured Guaranty US Holdings debt securities are denominated, in one or more foreign currencies or currency units, the restrictions, elections, U.S. federal income tax considerations, specific terms and other information will be set forth in the applicable prospectus supplement.

        Unless otherwise set forth in the applicable prospectus supplement, other than as described below under "—Covenants Applicable to Assured Guaranty US Holdings Senior Debt Securities—Limitation on Liens on Stock of Designated Subsidiaries," the Assured Guaranty US Holdings indentures do not contain any provisions that would limit the ability of Assured Guaranty US Holdings to incur indebtedness or that would afford holders of Assured Guaranty US Holdings debt securities protection in the event of a sudden and significant decline in the credit quality of Assured Guaranty US Holdings

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or Assured Guaranty or a takeover, recapitalization or highly leveraged or similar transaction involving Assured Guaranty US Holdings or Assured Guaranty. Accordingly, Assured Guaranty US Holdings or Assured Guaranty could, in the future, enter into transactions that could increase the amount of its outstanding indebtedness that could affect its respective capital structure or credit rating.

Assured Guaranty Guarantee

        We will fully and unconditionally guarantee all payments on the Assured Guaranty US Holdings debt securities. Unless otherwise set forth in the applicable prospectus supplement, our guarantee of the Assured Guaranty US Holdings senior debt securities will be an unsecured obligation of Assured Guaranty and will rank equally with all of our other unsecured and unsubordinated indebtedness. Our guarantee of the Assured Guaranty US Holdings subordinated debt securities will be an unsecured obligation of Assured Guaranty, subordinated in right of payment to the prior payment in full of all Assured Guaranty senior indebtedness.

        Since we are a holding company, our rights and the rights of our creditors, including you as a holder of the Assured Guaranty US Holdings debt securities who would be a creditor of ours by virtue of our guarantee, and shareholders to participate in any distribution of the assets of any subsidiary upon the subsidiary's liquidation or reorganization or otherwise would be subject to prior claims of the subsidiary's creditors, except to the extent that we may be a creditor of the subsidiary. The right of our creditors, including you, to participate in the distribution of the stock owned by us in some of our subsidiaries, including our insurance subsidiaries, may also be subject to approval by insurance regulatory authorities having jurisdiction over the subsidiaries.

Conversion and Exchange

        The terms, if any, on which Assured Guaranty US Holdings debt securities are convertible into or exchangeable for, either mandatorily or at your or Assured Guaranty US Holdings' option, common shares of Assured Guaranty, preferred shares of Assured Guaranty or other securities, whether or not issued by Assured Guaranty, property or cash, or a combination of any of these, will be set forth in the applicable prospectus supplement.

Payments of Additional Amounts

        We will make all payments on Assured Guaranty US Holdings debt securities without withholding of any present or future taxes or governmental charges of Bermuda, referred to in this prospectus as a taxing jurisdiction, unless we are required to do so by applicable law or regulation.

        If we are required to withhold amounts, we will, subject to the limitations described below, pay to you additional amounts so that every net payment made to you, after the withholding, will not be the same amount provided for in the Assured Guaranty US Holdings debt security and the applicable Assured Guaranty US Holdings indenture.

        We will not be required to pay any additional amounts for:

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        In addition, we will not pay additional amounts if you are a fiduciary or partnership or other than the sole beneficial owner of the Assured Guaranty US Holdings debt security if the beneficiary or partner or settlor would not have been entitled to the additional amounts had it been the holder of the Assured Guaranty US Holdings debt security.

Global Securities

        The Assured Guaranty US Holdings debt securities may be issued, in whole or in part, in the form of one or more global securities that will be deposited with, or on behalf of, a depositary identified in the applicable prospectus supplement and registered in the name of the depositary or its nominee. Interests in any global Assured Guaranty US Holdings debt security will be shown on, and transfers of the Assured Guaranty US Holdings debt securities will be effected only through, records maintained by the depositary and its participants as described below.

        The specific terms of the depositary arrangement will be described in the applicable prospectus supplement.

Covenants Applicable to Assured Guaranty US Holdings Senior Debt Securities

        Under the Assured Guaranty US Holdings senior indenture, each of Assured Guaranty US Holdings and Assured Guaranty has covenanted that, so long as any Assured Guaranty US Holdings senior debt securities are outstanding, it will not, nor will it permit any subsidiary to, create, incur, assume, guarantee or otherwise permit to exist any indebtedness secured by any security interest on any shares of capital stock of any designated subsidiary, unless Assured Guaranty US Holdings and Assured Guaranty concurrently provide that the Assured Guaranty US Holdings senior debt securities and, if Assured Guaranty US Holdings and Assured Guaranty elect, any other indebtedness of Assured Guaranty US Holdings that is not subordinate to the Assured Guaranty US Holdings senior debt securities and with respect to which the governing instruments require, or pursuant to which the

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Assured Guaranty US Holdings is otherwise obligated, to provide such security, will be secured equally with the indebtedness for at least the time period the other indebtedness is so secured.

        The term "designated subsidiary" means any present or future consolidated subsidiary of Assured Guaranty, the consolidated net worth of which constitutes at least 5% of Assured Guaranty's consolidated net worth.

        For purposes of the Assured Guaranty US Holdings indentures, the term "indebtedness" means, with respect to any person:

        The Assured Guaranty US Holdings senior indenture also provides that, so long as any Assured Guaranty US Holdings senior debt securities are outstanding and except in a transaction otherwise governed by the Assured Guaranty US Holdings indentures, neither Assured Guaranty US Holdings nor Assured Guaranty will issue, sell, assign, transfer or otherwise dispose of any shares of securities convertible into, or warrants, rights or options to subscribe for or purchase shares of, capital stock, other than preferred stock having no voting rights, of any designated subsidiary. Similarly, Assured Guaranty US Holdings will not permit any designated subsidiary to issue, other than to Assured Guaranty US Holdings or Assured Guaranty, these types of securities, warrants, rights or options, other than director's qualifying shares and preferred stock having no voting rights, of any designated subsidiary, if, after giving effect to the transaction and the issuance of the maximum number of shares issuable upon the conversion or exercise of all the convertible securities, warrants, rights or options, Assured Guaranty would own, directly or indirectly, less than 80% of the shares of capital stock of the designated subsidiary, other than preferred stock having no voting rights.

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        However, Assured Guaranty US Holdings may issue, sell, assign, transfer or otherwise dispose of securities if the consideration is at least a fair market value as determined by Assured Guaranty US Holdings' board or if required by law or regulation. Assured Guaranty US Holdings or Assured Guaranty, as the case may be, may also merge or consolidate any designated subsidiary into or with another direct or indirect subsidiary of Assured Guaranty, the shares of capital stock of which Assured Guaranty owns at least 80% or, subject to the provisions described under "—Consolidation, Amalgamation, Merger and Sale of Assets" below, sell, transfer or otherwise dispose of the entire capital stock of any designated subsidiary at one time if the consideration is at least fair market value as determined by Assured Guaranty US Holdings' or Assured Guaranty's board.

Consolidation, Amalgamation, Merger and Sale of Assets

        Each Assured Guaranty US Holdings indenture provides that Assured Guaranty US Holdings and Assured Guaranty may not:

unless:

Events of Default

        Each of the following events will constitute an event of default under each Assured Guaranty US Holdings indenture, whether it be voluntary or involuntary or be effected by operation of law or

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pursuant to any judgment, decree or order of any court or any order, rule or regulation of any administrative or governmental body:

        If an event of default with respect to the Assured Guaranty US Holdings debt securities of any series, other than events of bankruptcy, insolvency or reorganization, occurs and is continuing, either the trustee or the holders of not less than 25% in principal amount of the outstanding Assured Guaranty US Holdings debt securities of the series may declare the principal amount, or a lesser amount as may be provided for in the Assured Guaranty US Holdings debt securities, of all outstanding Assured Guaranty US Holdings debt securities of the series to be immediately due and payable by written notice. At any time after a declaration of acceleration has been made, but before a judgment or decree for payment of money has been obtained by the trustee, generally, the holders of not less than a majority in principal amount of the Assured Guaranty US Holdings debt securities of the series may rescind and annul the declaration of acceleration. Any event of bankruptcy, insolvency or reorganization will cause the principal amount and accrued interest, or the lesser amount as provided for in the Assured Guaranty US Holdings debt securities, to become immediately due and payable without any declaration or other act by the trustee or any holder.

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        In connection with the issuance of any debt securities, the supplemental indenture shall provide that notwithstanding the foregoing, at the election of Assured Guaranty or Assured guaranty US Holdings, the sole remedy for the failure by Assured Guaranty or Assured Guaranty US Holdings to comply with the covenant in the indenture requiring Assured Guaranty or Assured Guaranty US Holdings to file with the trustee copies of the reports and other information it files with the SEC ("Assured Guaranty/ Assured Guaranty US Holdings' SEC filing obligations") and for any failure by Assured Guaranty or Assured Guaranty US Holdings to comply with the requirements of Section 314(a)(1) of the TIA, which similarly requires Assured Guaranty or Assured Guaranty US Holdings to file with the trustee copies of the reports and other information it files with the SEC, shall, for the first 270 days after the occurrence of such failure consist exclusively of the right to receive additional interest on the debt securities of such series at an annual rate equal to 0.25% of the principal amount of the debt securities. This additional interest will accrue on the debt securities from and including the date on which a failure to comply with Assured Guaranty/ Assured Guaranty US Holdings' SEC filing obligations or the failure to comply with the requirements of Section 314(a)(1) of the TIA first occurs to but not including the 270th day thereafter (or such earlier date on which such failure shall have been cured or waived). On such 270th day (or earlier, if such failure is cured or waived prior to such 270th day), such additional interest will cease to accrue and, if such failure has not been cured or waived prior to such 270th day, then either the trustee or the holders of not less than 25% in the aggregate principal amount of the debt securities of such series then outstanding may declare the principal of all the debt securities of such series, together with accrued interest, to be due and payable immediately. However, prior to such 270th day, any such failure shall not be an event of default. This provision shall not affect the rights of holders in the event of the occurrence of any other event of default.

        Each Assured Guaranty US Holdings indenture provides that, within 90 days after the occurrence of any event which is, or after notice or lapse of time or both would become, an event of default the trustee must transmit, notice of the default to each holder of the Assured Guaranty US Holdings debt securities unless the default has been cured or waived. However, except in the case of a default in the payment of principal of, or premium or interest, if any, on or additional amounts or any sinking fund or purchase fund installment with respect to any Assured Guaranty US Holdings debt security, the trustee may withhold this notice if and so long as the board of directors, executive committee or trust committee of directors and/or responsible officers of the trustee determine in good faith that the withholding of the notice is in the best interest of the holders.

        If an event of default occurs and is continuing with respect to the Assured Guaranty US Holdings debt securities of any series, the trustee may, in its discretion, proceed to protect and enforce its rights and the rights of the holders of Assured Guaranty US Holdings debt securities by all appropriate judicial proceedings. Each Assured Guaranty US Holdings indenture provides that, subject to the duty of the trustee during any default to act with the required standard of care, the trustee will be under no obligation to exercise any of its rights or powers under the Assured Guaranty US Holdings indenture at the request or direction of any of the holders, unless the holders have offered the trustee reasonable indemnity. Subject to these indemnification provisions, the holders of a majority in principal amount of the outstanding Assured Guaranty US Holdings debt securities of any series will generally have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the Assured Guaranty US Holdings debt securities of the series.

Modification and Waiver

        Assured Guaranty US Holdings, Assured Guaranty and the trustee may modify or amend either Assured Guaranty US Holdings indenture with the consent of the holders of not less than a majority in principal amount of the outstanding Assured Guaranty US Holdings debt securities of each series

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affected by the modification or amendment, so long as the modification or amendment does not, without the consent of each affected holder:

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        In addition, no supplemental indenture may, directly or indirectly, modify or eliminate the subordination provisions of the Assured Guaranty US Holdings subordinated indenture in any manner which might terminate or impair the subordination of the Assured Guaranty US Holdings subordinated debt securities to senior indebtedness or the subordination of the related Assured Guaranty guarantee to Assured Guaranty senior indebtedness, without the prior written consent of the holders of the senior indebtedness or the Assured Guaranty senior indebtedness, respectively.

        Assured Guaranty US Holdings, Assured Guaranty and the trustee may modify or amend the Assured Guaranty US Holdings indenture and the Assured Guaranty US Holdings debt securities of any series without the consent of any holder in order to, among other things:

        The holders of at least a majority in principal amount of the outstanding Assured Guaranty US Holdings debt securities of any series may, on behalf of the holders of all Assured Guaranty US Holdings debt securities of that series, waive compliance by Assured Guaranty US Holdings and Assured Guaranty with specified covenants of the applicable Assured Guaranty US Holdings indenture. The holders of not less than a majority in principal amount of the outstanding Assured Guaranty US Holdings debt securities on behalf of the holders of all Assured Guaranty US Holdings debt securities of that series may waive any past default and its consequences with respect to the Assured Guaranty US Holdings debt securities of that series, except a default:

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        Under each Assured Guaranty US Holdings indenture, each of Assured Guaranty US Holdings and Assured Guaranty must annually furnish the trustee a statement regarding its performance of specified obligations and any default in its performance under the applicable Assured Guaranty US Holdings indenture. Each of Assured Guaranty US Holdings and Assured Guaranty is also required to deliver to the trustee, within five days after its occurrence, written notice of any event of default, or any event which after notice or lapse of time or both would constitute an event of default, resulting from the failure to perform or breach of any covenant or warranty contained in the applicable Assured Guaranty US Holdings indenture or the Assured Guaranty US Holdings debt securities of any series.

Discharge, Defeasance and Covenant Defeasance

        Assured Guaranty US Holdings or Assured Guaranty may discharge their payment obligations on the Assured Guaranty US Holdings debt securities, which we refer to as defeasance, or elect to be discharged from complying with the covenants in the Assured Guaranty US Holdings indentures, except for certain ministerial obligations, like registering transfers or exchanges of the Assured Guaranty US Holdings debt securities, which we refer to as covenant defeasance.

        Assured Guaranty US Holdings or Assured Guaranty may only do this if, among other things:

Subordination of Assured Guaranty US Holdings Subordinated Debt Securities

        The Assured Guaranty US Holdings subordinated debt securities will generally be subordinate in right of payment to the prior payment in full of all senior indebtedness. Upon any payment or distribution of assets of Assured Guaranty US Holdings of any kind or character, whether in cash, property or securities, to creditors upon any dissolution, winding-up, liquidation or reorganization of Assured Guaranty US Holdings, whether voluntary or involuntary, or in bankruptcy, insolvency, receivership or other proceedings, all amounts due upon all senior indebtedness will first be paid in full, or payment provided for in money in accordance with its terms, before the holders of Assured Guaranty US Holdings subordinated debt securities of that series are entitled to receive or retain any payment on account of principal of, or any premium or interest on, or any additional amounts with

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respect to, the Assured Guaranty US Holdings subordinated debt securities. This means that the holders of the senior indebtedness will be entitled to receive any payment or distribution, which may be payable or deliverable by reason of the payment of any other indebtedness of Assured Guaranty US Holdings being subordinated to the payment of Assured Guaranty US Holdings subordinated debt securities, which may be payable or deliverable in respect of the Assured Guaranty US Holdings subordinated debt securities upon any dissolution, winding-up, liquidation or reorganization or in any bankruptcy, insolvency, receivership or other proceeding.

        By reason of this subordination, in the event of liquidation or insolvency of Assured Guaranty US Holdings, holders of senior indebtedness and holders of other obligations of Assured Guaranty US Holdings that are not subordinated to the senior indebtedness may recover more, ratably, than the holders of the Assured Guaranty US Holdings subordinated debt securities.

        Subject to the payment in full of all senior indebtedness, the rights of the holders of the Assured Guaranty US Holdings subordinated debt securities will be subrogated to the rights of the holders of the senior indebtedness to receive payments or distributions of cash, property or securities of Assured Guaranty US Holdings applicable to the senior indebtedness until the principal of, any premium and interest on, and any additional amounts with respect to, the Assured Guaranty US Holdings subordinated debt securities have been paid in full.

        No payment of principal of, including redemption and sinking fund payments, or any premium or interest on or any additional amounts with respect to the Assured Guaranty US Holdings subordinated debt securities may be made by Assured Guaranty US Holdings if:

        The Assured Guaranty US Holdings subordinated indenture does not limit or prohibit Assured Guaranty US Holdings from incurring additional senior indebtedness, which may include indebtedness that is senior to the Assured Guaranty US Holdings subordinated debt securities, but subordinate to other obligations of Assured Guaranty US Holdings. The Assured Guaranty US Holdings senior debt securities will constitute senior indebtedness with respect to the Assured Guaranty US Holdings subordinated debt securities.

        The term "senior indebtedness" means, with respect to the Assured Guaranty US Holdings subordinated debt securities of any particular series, all indebtedness of Assured Guaranty US Holdings outstanding at any time, except:

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        Senior indebtedness with respect to the Assured Guaranty US Holdings subordinated debt securities shall continue to be entitled to the benefits of the subordination provisions irrespective of any amendment, modification or waiver of any term of the senior indebtedness.

        The Assured Guaranty US Holdings subordinated indenture provides that the subordination provisions, insofar as they relate to any particular series of Assured Guaranty US Holdings subordinated debt securities, may be changed prior to issuance of the applicable Assured Guaranty US Holdings subordinated debt securities, which change would be described in the applicable prospectus supplement.

Subordination of Assured Guaranty Guarantee of Assured Guaranty US Holdings Subordinated Debt Securities

        The Assured Guaranty guarantee of Assured Guaranty US Holdings subordinated debt securities will generally be subordinate in right of payment to the prior payment in full of all Assured Guaranty senior indebtedness. Upon any payment or distribution of assets of Assured Guaranty of any kind or character, whether in cash, property or securities, to creditors upon any dissolution, winding-up, liquidation or reorganization of Assured Guaranty, whether voluntary or involuntary, or in bankruptcy, insolvency, receivership or other proceedings, all amounts due upon all Assured Guaranty senior indebtedness will first be paid in full, or payment of the Assured Guaranty senior indebtedness provided for in money in accordance with its terms, before the holders of Assured Guaranty US Holdings subordinated debt securities are entitled to receive or retain any payment from Assured Guaranty on account of principal of, or any premium or interest on, or any additional amounts with respect to, the Assured Guaranty US Holdings subordinated debt securities. This means that the holders of Assured Guaranty senior indebtedness shall be entitled to receive any payment or distribution by Assured Guaranty of any kind or character, including any payment or distribution which may be payable or deliverable by Assured Guaranty by reason of the payment of any other indebtedness of Assured Guaranty being subordinated to the payment of Assured Guaranty US Holdings subordinated debt securities, which may be payable or deliverable by Assured Guaranty in respect of the Assured Guaranty US Holdings subordinated debt securities upon any dissolution, winding-up, liquidation or reorganization or in any bankruptcy, insolvency, receivership or other proceeding.

        By reason of this subordination, in the event of liquidation or insolvency of Assured Guaranty, holders of Assured Guaranty senior indebtedness and holders of other obligations of Assured Guaranty that are not subordinated to the Assured Guaranty senior indebtedness may recover more, ratably, than the holders of the Assured Guaranty US Holdings subordinated debt securities.

        Subject to the payment in full of all Assured Guaranty senior indebtedness, the rights of the holders of the Assured Guaranty US Holdings subordinated debt securities under the Assured Guaranty guarantee will be subrogated to the rights of the holders of the Assured Guaranty senior indebtedness to receive payments or distributions of cash, property or securities of Assured Guaranty applicable to the Assured Guaranty senior indebtedness until the principal of, any premium and interest on, and any additional amounts with respect to, the Assured Guaranty US Holdings senior debt securities have been paid in full.

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        No payment of principal of, including redemption and sinking fund payments, or any premium or interest on or any additional amounts with respect to the Assured Guaranty US Holdings subordinated debt securities of any series may be made by Assured Guaranty if:

        The Assured Guaranty US Holdings subordinated indenture does not limit or prohibit Assured Guaranty from incurring additional Assured Guaranty senior indebtedness, which may include indebtedness that is senior to the Assured Guaranty guarantee of the Assured Guaranty US Holdings subordinated debt securities, but subordinate to other obligations of Assured Guaranty. The Assured Guaranty senior debt securities will constitute Assured Guaranty senior indebtedness with respect to the Assured Guaranty US Holdings subordinated debt securities.

        The term "Assured Guaranty senior indebtedness" means, with respect to the Assured Guaranty US Holdings subordinated debt securities of any particular series, all indebtedness of Assured Guaranty outstanding at any time, except:

        The Assured Guaranty US Holdings subordinated indenture provides that the subordination provisions, insofar as they relate to any particular series of Assured Guaranty US Holdings subordinated debt securities, may be changed prior to the issuance of that series of Assured Guaranty US Holdings subordinated debt securities, which change would be described in the applicable prospectus supplement.

New York Law to Govern

        The Assured Guaranty US Holdings indentures are, and the Assured Guaranty US Holdings debt securities and the Assured Guaranty guarantee will be, governed by, and construed in accordance with, the laws of the state of New York.


DESCRIPTION OF THE WARRANTS TO PURCHASE ASSURED GUARANTY
COMMON SHARES OR PREFERRED SHARES

        The following summary sets forth the material terms and provisions of the common share warrants and preferred share warrants, which would be issued pursuant to a stock warrant agreement between Assured Guaranty and a stock warrant agent to be selected at the time of issue. The stock warrant agreement may include or incorporate by reference standard warrant provisions substantially in the

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form of the standard stock warrant provisions, which is filed as an exhibit to the registration statement of which this prospectus forms a part.

General

        The stock warrants may be issued under the stock warrant agreement independently or together with any other securities offered by a prospectus supplement. If stock warrants are offered, the applicable prospectus supplement will describe the designation and terms of the stock warrants, including, without limitation, the following:

        The common shares or preferred shares issuable upon exercise of the stock warrants will, when issued in accordance with the stock warrant agreement, be fully paid and nonassessable. This means that the shares will be paid for in full at the time they are issued, and, once they are paid for in full, there will be no further liability for further assessments or taxation.

Exercise of Stock Warrants

        You may exercise your stock warrants by surrendering to the stock warrant agent your stock warrant certificate with the form of election to purchase on the reverse of the certificate properly completed and executed by you, or your authorized agent, which signature must be guaranteed by a bank or trust company, by a broker or dealer which is a member of the National Association of Securities Dealers, Inc., which we refer to in this prospectus as the NASD, or by a member of a national securities exchange. You must indicate on the form of election whether you are electing to exercise all or a portion of the stock warrants evidenced by the certificate. You must also submit a payment of the aggregate exercise price of the stock warrants to be exercised in lawful money of the United States along with your stock warrant certificates, unless otherwise set forth in the applicable prospectus supplement. Upon receipt of the stock warrant certificate, form of election and aggregate payment, if applicable, by the stock warrant agent, the stock warrant agent will requisition from the transfer agent for the common shares or the preferred shares, as the case may be, a certificate representing the number of common shares or preferred shares purchased for issuance and delivery to you or upon your written order. If you exercise less than all of the stock warrants evidenced by any

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stock warrant certificate, the stock warrant agent shall deliver to you a new stock warrant certificate representing your unexercised stock warrants.

Anti-dilution and Other Provisions

        The exercise price payable, the number of common shares or preferred shares purchasable upon the exercise of each stock warrant and the number of stock warrants outstanding are subject to adjustment if specified events occur. These events include:

        In lieu of adjusting the number of common shares or preferred shares purchasable upon exercise of each stock warrant, Assured Guaranty may elect to adjust the number of stock warrants. No adjustment in the number of shares purchasable upon exercise of the stock warrants will be required until cumulative adjustments require an adjustment of at least 1% in the number of shares purchasable. We may also, at our option, reduce the exercise price at any time. No fractional shares will be issued upon exercise of stock warrants, but we will pay the cash value of any fractional shares otherwise issuable. Notwithstanding the preceding sentences, in case of any consolidation, merger, or sale or conveyance of our property as an entirety or substantially as an entirety, you, as a stock warrant holder, shall have the right to the kind and amount of shares of stock and other securities and property, including cash, receivable by a holder of the number of common shares or preferred shares into which your stock warrants were exercisable immediately prior to this event.

No Rights as Shareholders

        You will not be entitled, by virtue of being a stock warrant holder, to vote, to consent, to receive dividends, to receive notice as shareholders with respect to any meeting of shareholders for the election of our directors or any other matter, or to exercise any rights whatsoever as shareholders of Assured Guaranty.


DESCRIPTION OF THE WARRANTS TO PURCHASE DEBT SECURITIES

        The following summary sets forth the material terms and provisions of the debt warrants, which would be issued pursuant to a debt warrant agreement between Assured Guaranty and a debt warrant agent to be selected at the time of issue. The debt warrant agreement may include or incorporate by reference standard warrant provisions substantially in the form of the standard debt warrant provisions, which is filed as an exhibit to the registration statement of which this prospectus forms a part.

General

        The debt warrants may be issued under the debt warrant agreement independently or together with any other securities offered by a prospectus supplement. If debt warrants are offered, the applicable prospectus supplement will describe the designation and terms of the debt warrants, including, without limitation, the following:

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        You, as a debt warrant holder, will generally not have any of the rights of holders of Assured Guaranty debt securities, including the right to receive the payment of principal of, any premium or interest on, or any additional amounts with respect to, the Assured Guaranty debt securities or to enforce any of the covenants of the Assured Guaranty debt securities or the applicable Assured Guaranty indenture.

Exercise of Debt Warrants

        You may exercise your debt warrants by surrendering at the office of the debt warrant agent your debt warrant certificate with the form of election to purchase on the reverse side of the certificate properly completed and signed by you, which signature must be guaranteed by a bank or trust company, by a broker or dealer which is a member of the NASD or by a member of a national securities exchange. You must also submit a payment in full of the exercise price, as set forth in the applicable prospectus supplement. Upon the exercise of debt warrants, Assured Guaranty will issue the Assured Guaranty debt securities in authorized denominations in accordance with your instructions. If you exercise less than all of the debt warrants evidenced by your debt warrant certificate, a new debt warrant certificate will be issued for the remaining number of debt warrants.


DESCRIPTION OF STOCK PURCHASE CONTRACTS
AND STOCK PURCHASE UNITS

        We may issue stock purchase contracts, representing contracts obligating you to purchase from us, and obligating us to sell to you, a specified number of common shares at a future date or dates. The price per common share may be fixed at the time the stock purchase contracts are issued or may be determined by reference to a specific formula set forth in the stock purchase contracts.

        The stock purchase contracts may be issued separately or as a part of stock purchase units consisting of a stock purchase contract and, as security for your obligations to purchase the common shares under the stock purchase contracts, either:

        The stock purchase contracts may require us to make periodic payments to you or vice versa, and these payments may be unsecured or prefunded on some basis. The stock purchase contracts may require you to secure your obligations in a specified manner, and, in some circumstances, we may

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deliver newly issued prepaid stock purchase contracts upon release to you of any collateral securing your obligations under the original stock purchase contract.

        The applicable prospectus supplement will describe the specific terms of any stock purchase contracts or stock purchase units and, if applicable, prepaid stock purchase contracts. However, that description will not purport to be complete and will be qualified in its entirety by reference to:


PLAN OF DISTRIBUTION

        Assured Guaranty and/or Assured Guaranty US Holdings may sell offered securities in any one or more of the following ways from time to time:

        The applicable prospectus supplement will set forth the specific terms of the offering of the offered securities, including:

        The distribution of the offered securities may be effected from time to time:

        Offers to purchase offered securities may be solicited by agents designated by Assured Guaranty from time to time. Any agent involved in the offer or sale of the offered securities in respect of which this prospectus is delivered will be named, and any commissions payable by Assured Guaranty and/or Assured Guaranty US Holdings to the agent will be set forth, in the applicable prospectus supplement. Unless otherwise set forth in the applicable prospectus supplement, any agent will be acting on a reasonable best efforts basis for the period of its appointment. Any agent may be deemed to be an underwriter, as that term is defined in the Securities Act, of the offered securities so offered and sold.

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        If offered securities are sold to the public by means of an underwritten offering, either through underwriting syndicates represented by managing underwriters or directly by the managing underwriters, Assured Guaranty and/or Assured Guaranty US Holdings will execute an underwriting agreement with an underwriter or underwriters, and the names of the specific managing underwriter or underwriters, as well as any other underwriters, will be set forth in the applicable prospectus supplement. In addition, the terms of the transaction, including commissions, discounts and any other compensation of the underwriters and dealers, if any, will be set forth in the applicable prospectus supplement, which prospectus supplement will be used by the underwriters to make resales of the offered securities. If underwriters are utilized in the sale of the offered securities, the offered securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including:

        In addition, unless otherwise indicated in the prospectus supplement, the underwriting agreement will provide that the obligations of the underwriters are subject to specified conditions precedent and that the underwriters with respect to a sale of offered securities will be obligated to purchase all of the offered securities of a series if any are purchased.

        Assured Guaranty and/or Assured Guaranty US Holdings may grant to the underwriters options to purchase additional offered securities to cover over-allotments, if any, at the public offering price, with additional underwriting discounts or commissions as may be set forth in the applicable prospectus supplement. If Assured Guaranty and/or Assured Guaranty US Holdings grants any over-allotment option, the terms of the over-allotment option will be set forth in the applicable prospectus supplement.

        If a dealer is utilized in the sales of offered securities, Assured Guaranty and/or Assured Guaranty US Holdings will sell the offered securities to the dealer as principal. The dealer may then resell the offered securities to the public at varying prices to be determined by the dealer at the time of resale. Any dealer may be deemed to be an underwriter of the offered securities so offered and sold. The name of the dealer and the terms of the transaction will be set forth in the applicable prospectus supplement.

        Offers to purchase offered securities may be solicited directly by Assured Guaranty and/or Assured Guaranty US Holdings, and the sale of the offered securities may be made by Assured Guaranty and/or Assured Guaranty US Holdings directly to institutional investors or others with respect to any resale of the offered securities. The terms of any of these sales will be described in the applicable prospectus supplement.

        Offered securities may also be offered and sold in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise by one or more remarketing firms acting as principals for their own accounts or as agents for Assured Guaranty and/or Assured Guaranty US Holdings. Any remarketing firm will be identified and the terms of its agreements, if any, with Assured Guaranty and/or Assured Guaranty US Holdings and its compensation will be described in the applicable prospectus supplement. Remarketing firms may be deemed to be underwriters in connection with the offered securities remarketed by them.

        Agents, underwriters, dealers and remarketing firms may be entitled, under agreements entered into with Assured Guaranty and/or Assured Guaranty US Holdings, to indemnification by Assured Guaranty and/or Assured Guaranty US Holdings against some civil liabilities, including liabilities under the Securities Act that may arise from any untrue statement or alleged untrue statement of a material

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fact or any omission or alleged omission to state a material fact in this prospectus, any supplement or amendment hereto, or in the registration statement of which this prospectus forms a part, or to contribution with respect to payments which the agents, underwriters or dealers may be required to make.

        Assured Guaranty and/or Assured Guaranty US Holdings may authorize underwriters or other persons acting as Assured Guaranty's and/or Assured Guaranty US Holdings' agents to solicit offers by specified institutions to purchase offered securities from Assured Guaranty and/or Assured Guaranty US Holdings, pursuant to contracts providing for payments and delivery on a future date, which will be set forth in the applicable prospectus supplement. Institutions with which these contracts may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and others. However, in all cases, these institutions must be approved by Assured Guaranty and/or Assured Guaranty US Holdings. The obligations of any purchaser under any contract will be subject to the condition that the purchase of the offered securities shall not, at the time of delivery, be prohibited under the laws of the jurisdiction to which the purchaser is subject. The underwriters and other agents will not have any responsibility in respect of the validity or performance of these contracts.

        Each series of offered securities will be a new issue and, other than the common shares, which are listed on the NYSE, will have no established trading market. Assured Guaranty and/or Assured Guaranty US Holdings may elect to list any series of offered securities on an exchange and, in the case of the common shares, on any additional exchange. However, unless otherwise specified in the applicable prospectus supplement, none of Assured Guaranty and/or Assured Guaranty US Holdings shall be obligated to do so. No assurance can be given as to the liquidity of the trading market for any of the offered securities.

        Underwriters, dealers, agents and remarketing firms may be customers of, engage in transactions with, or perform services for, Assured Guaranty and its subsidiaries in the ordinary course of business.


LEGAL MATTERS

        Certain matters as to U.S. and New York law in connection with this offering will be passed upon for us by Mayer Brown LLP, Chicago, Illinois. Certain matters as to Bermuda law will be passed upon for us by Conyers Dill & Pearman, Hamilton, Bermuda.


EXPERTS

        The financial statements and management's assessment of the effectiveness of internal control over financial reporting (which is included in Management's Report on Internal Control over Financial Reporting) incorporated in this prospectus by reference to our Annual Report on Form 10-K for the year ended December 31, 2008 have been so incorporated in reliance on the reports of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in accounting and auditing.

        The financial statements of Financial Security Assurance Holdings Ltd. ("FSAH") and management's assessment of the effectiveness of internal control over financial reporting (which is included in Management's Report on Internal Control over Financial Reporting) incorporated in this prospectus by reference to FSAH's Annual Report on Form 10-K for the year ended December 31, 2008 have been so incorporated in reliance on the reports of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in accounting and auditing.

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ENFORCEABILITY OF CIVIL LIABILITIES UNDER UNITED STATES
FEDERAL SECURITIES LAWS AND OTHER MATTERS

        We are organized under the laws of Bermuda. In addition, some of our directors and officers reside outside the United States, and a portion of their assets and our assets are or may be located in jurisdictions outside the United States. Therefore, it may be difficult for investors to effect service of process within the United States upon Assured Guaranty or its non-U.S. directors and officers or to recover against us or our non-U.S. directors and officers on judgments of U.S. courts, including judgments predicated upon the civil liability provisions of the U.S. federal securities laws. Further, no claim may be brought in Bermuda against us or our directors and officers in the first instance for violation of U.S. federal securities laws because these laws have no extraterritorial jurisdiction under Bermuda law and do not have force of law in Bermuda. A Bermuda court may, however, impose civil liability, including the possibility of monetary damages, on us or our directors and officers if the facts alleged in a complaint constitute or give rise to a cause of action under Bermuda law. However, we may be served with process in the United States with respect to actions against us arising out of or in connection with violations of U.S. federal securities laws relating to offers and sales of common shares made hereby by serving our U.S. agent irrevocably appointed for that purpose.

        We have been advised by Conyers Dill & Pearman, our special Bermuda counsel, that there is doubt as to whether the courts of Bermuda would enforce judgments of U.S. courts obtained in actions against us or our directors and officers, as well as the experts named herein, predicated upon the civil liability provisions of the U.S. federal securities laws or original actions brought in Bermuda against us or such persons predicated solely upon U.S. federal securities laws. A Bermuda court would likely enforce a final and conclusive judgment in personam, which means a judgment against a specific person rather than against specific property, obtained in a court in the United States under which a sum of money is payable, other than a sum of money payable in respect of multiple damages, taxes or other charges of a similar nature or in respect of a fine or other penalty, provided that the Bermuda court was satisfied that each of the following conditions was met:

        Further, we have been advised by Conyers Dill & Pearman that there is no treaty in effect between the United States and Bermuda providing for the enforcement of judgments of U.S. courts, and there are grounds upon which Bermuda courts may not enforce judgments of U.S. courts. Some remedies available under the laws of U.S. jurisdictions, including some remedies available under the U.S. federal securities laws, may not be allowed in Bermuda courts as contrary to that jurisdiction's public policy. Because judgments of U.S. courts are not automatically enforceable in Bermuda, it may be difficult for you to recover against us based upon such judgments.


WHERE YOU CAN FIND MORE INFORMATION

        Assured Guaranty files annual, quarterly and special reports, proxy statements and other information with the SEC. FSAH files annual, quarterly and special reports and other information with the SEC. Assured Guaranty's and FSAH's SEC filings are available to the public over the Internet at the SEC's website at http://www.sec.gov. You may read and copy any document we or FSAH files in the

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SEC's Public Reference Room, 100 F Street, N.E., Washington, D.C. 20549. You may also obtain copies of this information by mail from the Public Reference Section of the SEC, 100 F Street, N.E., Washington, D.C. 20549, at prescribed rates. You may obtain information on the operation of the SEC's Public Reference Room in Washington, D.C. by calling the SEC at 1-800-SEC-0330. The SEC also maintains an Internet website that contains reports, proxy statements and other information about issuers, like Assured Guaranty and FSAH, that file electronically with the SEC. The address of that site is http://www.sec.gov. The SEC file number for documents Assured Guaranty files under the Exchange Act is 001-32141. The SEC file number for documents FSAH files under the Exchange Act is 1-12644. Assured Guaranty's and FSAH's SEC filings are also available at the office of the New York Stock Exchange, 20 Broad Street, New York, New York 10005. For further information on obtaining copies of our public filings at the NYSE, you should call (212) 656-5060.

        Assured Guaranty is allowed to "incorporate by reference" information filed with the SEC, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus, and information that Assured Guaranty or FSAH files subsequently with the SEC will automatically update and supersede the information included and/or incorporated by reference in this prospectus. Assured Guaranty incorporates by reference the documents listed below and any future filings made by it or FSAH with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the after the initial filing of the registration statement that contains this prospectus and prior to the time that Assured Guaranty sells all of the securities offered by this prospectus:

Assured SEC Filings:

FSAH SEC Filings:

        You may request a copy of these filings, other than exhibits unless that exhibit is specifically incorporated by reference into that filing, at no cost, by writing or telephoning us at the following address:

Assured SEC Filings:
Investor Relations
Assured Guaranty Ltd.
30 Woodbourne Avenue
Hamilton HM 08 Bermuda
Telephone: (441) 296-4004
  FSAH SEC Filings:
Investor Relations
Financial Security Assurance Holdings Ltd.
31 West 52nd Street
New York, New York 10019
Telephone: (212) 826-0100

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23,924,000 Shares

GRAPHIC

Assured Guaranty Ltd.

Common Shares


Prospectus Supplement


UBS Investment Bank

November 30, 2009