Exhibit 1.1

American Capital Agency Corp., a Delaware corporation (the “Company”), and American Capital Agency Management, LLC, a Delaware limited liability company and the manager of the Company (the “Manager”), confirm their agreement with each of the Underwriters named in Schedule I hereto (collectively, the “Underwriters,” which term shall also include any underwriter substituted as hereinafter provided in Section 10 hereof), for whom Citigroup Global Markets Inc. and Merrill Lynch, Pierce, Fenner & Smith Incorporated are acting as representatives (in such capacity, the “Representatives”), with respect to (i) the sale by the Company, and the purchase by the Underwriters, acting severally and not jointly, of 12,500,000 shares of common stock, par value $0.01 per share, of the Company (“Common Stock”) and (ii) the grant by the Company to the Underwriters, acting severally and not jointly, of the option described in Section 2(b) hereof to purchase all or any part of 1,875,000 additional shares of Common Stock to cover over-allotments, if any. The aforesaid 12,500,000 shares of Common Stock (the “Initial Securities”) to be purchased by the Underwriters and all or any part of the 1,875,000 shares of Common Stock subject to the option described in Section 2(b) hereof (the “Option Securities”) are hereinafter called, collectively, the “Securities.”

The Company and the Manager understand that the Underwriters propose to make a public offering of the Securities as soon as the Representatives deem advisable after this Agreement has been executed and delivered.

The Company has filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-11 (Registration No. 333-149167) (“Registration Statement 333-

149167”), including a related preliminary prospectus, for the registration of the Securities under the Securities Act of 1933, as amended (the “1933 Act”). Registration Statement 333-149167, as amended on or prior to the Applicable Time (as defined below), has been declared effective by the Commission under the 1933 Act and the rules and regulations of the Commission under the 1933 Act (the “1933 Act Regulations”). Promptly after execution and delivery of this Agreement, the Company will prepare and file a prospectus in accordance with the provisions of Rule 430A (“Rule 430A”) of the 1933 Act Regulations and paragraph (b) of Rule 424 (“Rule 424(b)”) of the 1933 Act Regulations. Any information included in such prospectus that was omitted from Registration Statement 333-149167 at the time it became effective but that is deemed to be part of and included therein pursuant to Rule 430A is referred to as “Rule 430A Information.” Each prospectus used in connection with the offering of the Securities that omitted the Rule 430A Information is herein called a “preliminary prospectus.” Registration Statement 333-149167, on each date and time that such registration statement and any post-effective amendment or amendments become or becomes effective (each, an “Effective Date”), including all documents filed as a part thereof, including any information contained in a Prospectus (as defined below) subsequently filed with the Commission pursuant to Rule 424(b) and deemed part of such registration statement, collectively, are herein called the “Registration Statement.” Any registration statement filed pursuant to Rule 462(b) of the 1933 Act Regulations is herein referred to as the “Rule 462(b) Registration Statement,” and after such filing the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The term “Prospectus” means the final prospectus relating to the Securities, in the form first filed with the Commission pursuant to paragraph (1) or (4) of Rule 424(b), and any amendments or supplements thereto. For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to be the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval system (“EDGAR”).

All references in this Agreement to financial statements and schedules and other information which is “contained,” “included” or “stated” in the Registration Statement, the Disclosure Package or the Prospectus (or other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information that is deemed by the 1933 Act Regulations to be a part of or included in the Registration Statement, the Disclosure Package or the Prospectus, as the case may be.

(a) Representations and Warranties by the Company. The Company represents and warrants to each Underwriter as of the date hereof, as of the Applicable Time referred to in Section 1(a)(ii) hereof, as of the Closing Time referred to in Section 2(c) hereof, and as of each Date of Delivery (if any) referred to in Section 2(b) hereof, and agrees with each Underwriter, as follows:

(i) Status under the Securities Act. At the time of filing the Registration Statement, at the earliest time thereafter that the Company or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) of the 1933 Act Regulations) of the Securities and at the date hereof, the Company was not and is not an “ineligible issuer,” as defined in Rule 405 of the 1933 Act Regulations (“Rule 405”).

(ii) Registration Statement, Prospectus and Disclosure Package at Time of Sale. Each of the Registration Statement, any Rule 462(b) Registration Statement and any post-effective amendment thereto has become effective under the 1933 Act and no stop order suspending the effectiveness of the Registration Statement, any Rule 462(b) Registration Statement or any post-effective amendment thereto has been issued under the 1933 Act and no proceedings for that purpose have been instituted or are pending or, to the knowledge of the Company, are contemplated by the Commission, and any request on the part of the Commission

for additional information has been complied with. The Company has not distributed any offering material in connection with the offering or sale of the Securities other than the Registration Statement, the preliminary prospectus, if any, the Disclosure Package (as defined below) and the Prospectus.

At the respective times the Registration Statement, any Rule 462(b) Registration Statement and each amendment thereto became effective and at the Closing Time (and, if any Option Securities are purchased, at the Date of Delivery), the Registration Statement, the Rule 462(b) Registration Statement and any amendments and supplements thereto complied and will comply in all material respects with the requirements of the 1933 Act and the 1933 Act Regulations and did not and will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading.

Neither the Prospectus nor any amendments or supplements thereto, at the time the Prospectus or any such amendment or supplement was issued and at the Closing Time (and, if any Option Securities are purchased, at the Date of Delivery), included or will include an untrue statement of a material fact or omitted or will omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.

Each preliminary prospectus (delivered to the Underwriters for use in connection with the offering contemplated by this Agreement) and the Prospectus (including any amendments or supplements thereto) complied when so filed in all material respects with the 1933 Act Regulations and each preliminary prospectus and the Prospectus delivered to the Underwriters for use in connection with this offering was identical to the electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T.

As of the Applicable Time (as defined below) and as of the Closing Time, neither (x) the Issuer General Use Free Writing Prospectus(es) (as defined below) issued at or prior to the Applicable Time, the Statutory Prospectus (as defined below) as of the Applicable Time and the information included on Schedule II hereto, all considered together (collectively, the “Disclosure Package”), nor (y) any individual Issuer Limited Use Free Writing Prospectus (as defined below), when considered together with the Disclosure Package, included any untrue statement of a material fact or omitted to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.

“Applicable Time” means [a.m.][p.m.] (New York City time) on May , 2008 or such other time as agreed by the Company and the Representatives.

“Issuer Free Writing Prospectus” means any “issuer free writing prospectus,” as defined in Rule 433 of the 1933 Act Regulations (“Rule 433”), relating to the Securities that (i) is required to be filed with the Commission by the Company, (ii) is a “road show that is a written communication” within the meaning of Rule 433(d)(8)(i), whether or not required to be filed with the Commission or (iii) is exempt from filing pursuant to Rule 433(d)(5)(i) because it contains a description of the Securities or of the offering that does not reflect the final terms, in each case in the form filed or required to be filed with the Commission or, if not required to be filed, in the form retained in the Company’s records pursuant to Rule 433(g).

“Issuer General Use Free Writing Prospectus” means any Issuer Free Writing Prospectus that is intended for general distribution to prospective investors (other than a Bona Fide Electronic Road Show (as defined below)), as evidenced by its being specified in Schedule III hereto.

“Issuer Limited Use Free Writing Prospectus” means any Issuer Free Writing Prospectus that is not an Issuer General Use Free Writing Prospectus.

“Statutory Prospectus” as of any time means the prospectus relating to the Securities that is included in the Registration Statement immediately prior to that time, including any preliminary or other prospectus deemed to be a part thereof.

The Company has made available a “bona fide electronic road show,” as defined in Rule 433, in compliance with Rule 433(d)(8)(ii) (the “Bona Fide Electronic Road Show”) such that no filing of any “road show” (as defined in Rule 433(h)) is required in connection with the offering of the Securities.

Each Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Securities or until any earlier date that the issuer notified or notifies the Representatives as described in Section 3(e) hereof, did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained in the Registration Statement, the Disclosure Package or the Prospectus, and any preliminary or other prospectus deemed to be a part thereof that has not been superseded or modified.

The representations and warranties in this subsection shall not apply to statements in or omissions from the Registration Statement, the Disclosure Package, the Prospectus or any Issuer Free Writing Prospectus made in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives expressly for use therein, which information is specified in Section 6(b) hereof.

(iii) Financial Data. The balance sheet of the Company, including the notes thereto, included in the Registration Statement, the Disclosure Package and the Prospectus present fairly the financial position of the respective entities to which such financial data relate (the “Covered Entities”) as of the dates indicated; the supporting schedules included in the Registration Statement, if any, fairly present the information required to be stated therein; such financial data has been prepared in conformity with generally accepted accounting principles as applied in the United States (“GAAP”) (except as may be expressly stated in the related notes thereto) and in accordance with Regulation S-X promulgated by the Commission; the financial data set forth in the Registration Statement, the Disclosure Package, each preliminary prospectus (delivered to the Underwriters for use in connection with the offering contemplated by this Agreement) and the Prospectus fairly present the information shown therein and has been compiled on a basis consistent with the financial data included in the Registration Statement, the Disclosure Package and the Prospectus; no other financial statements or supporting schedules are required to be included in the Registration Statement; the selected financial data set forth under the caption “Selected Financial Information” in the Registration Statement, the Disclosure Package, each such preliminary prospectus and the Prospectus fairly present the information included therein; all disclosures contained in the Registration Statement, the Disclosure Package or the Prospectus, regarding “non-GAAP financial measures” (as such term is defined by the rules and regulations of the Commission), if any, comply with Regulation G of the Securities Exchange Act of 1934, as amended (the “1934 Act”) and Item 10 of Regulation S-K of the 1933 Act, to the extent applicable.

(iv) Independent Accountants. Ernst & Young LLP, who certified the balance sheet of the Covered Entities included in the Registration Statement, the Disclosure Package and the Prospectus, is, and was during the period covered by its report, an independent registered public accounting firm as required by the 1933 Act and the 1933 Act Regulations and the Public Company Accounting Oversight Board (United States).

(v) No Material Adverse Change in Business. Since the respective dates as of which information is given in the Registration Statement, the Disclosure Package, each preliminary prospectus (delivered to the Underwriters for use in connection with the offering contemplated by this Agreement) and the Prospectus, except as otherwise stated therein, as of the date hereof and the Closing Time (and, if any option securities are purchased, at the Date of Delivery) (A) there has been no material adverse change in the condition, financial or otherwise, or in the earnings, business affairs or business prospects of the Company and each of its subsidiaries, all of which are listed on Schedule IV attached hereto (each, a “Subsidiary” and collectively, the “Subsidiaries”) considered as one enterprise, whether or not arising in the ordinary course of business (a “Material Adverse Effect”), (B) there have been no transactions entered into by the Company or any of its Subsidiaries, other than those in the ordinary course of business, which are material with respect to the Company and its Subsidiaries considered as one enterprise, (C) there has been no obligation, contingent or otherwise, directly or indirectly incurred by the Company or any Subsidiaries that could reasonably be likely to have a Material Adverse Effect, and (D) there has been no dividend or distribution of any kind declared, paid or made by the Company on any class of its capital stock or repurchase or redemption by the Company or any class of its capital stock.

(vi) Good Standing of the Company. The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Delaware and has the power and authority to own, lease and operate its properties and to conduct its business as described in the Registration Statement, the Disclosure Package and the Prospectus and to enter into and perform its obligations under this Agreement. The Company is duly qualified as a foreign corporation to transact business and is in good standing in each other jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except where the failure, individually or in the aggregate, so to qualify or to be in good standing would not result in a Material Adverse Effect.

(vii) Subsidiaries. Each Subsidiary is duly incorporated or organized and is validly existing and in good standing under the laws of the jurisdiction of its incorporation or organization, with requisite power and authority to own, lease and operate its properties and to conduct its business as described in the Registration Statement, the Disclosure Package and the Prospectus, and to consummate the transactions contemplated hereby. Each Subsidiary is duly qualified as a foreign corporation, limited liability company, partnership or trust to transact business and is in good standing in each other jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except where the failure so to qualify or to be in good standing would not result in a Material Adverse Effect. All issued and outstanding equity interests in each Subsidiary are owned directly or indirectly by the Company and have been duly authorized and validly issued and have not been issued in violation of, or subject to, any preemptive right, co-sale right, registration right, right of first refusal or other similar right of equity holders arising by operation of law, under the organizational documents of such Subsidiary, under any agreement to which such Subsidiary is a

party or otherwise, and are owned by the Company, directly or indirectly, free and clear of any pledge, security interests, liens, encumbrances, claims or equitable interests. Except as disclosed in the Prospectus, the Company does not, and as of the Closing Time (and, if any Option Securities are purchased, at the Date of Delivery) will not, own or control, directly or indirectly, any equity interest in any corporation, partnership, joint venture, limited liability company, association or other entity other than the Subsidiaries.

(viii) Capitalization. The authorized, issued and outstanding capital stock of the Company, in each case as of the date of this Agreement, is as set forth in the Registration Statement, the Disclosure Package and the Prospectus. The issued and outstanding shares of capital stock of the Company have been duly authorized and validly issued and are fully paid and non-assessable; none of the outstanding shares of capital stock of the Company were issued in violation of preemptive or other similar rights of any securityholder of the Company. Upon completion of the issuance and sale of the Securities pursuant to this Agreement, the capitalization of the Company will be as set forth in the Prospectus in the column entitled “As of January 11, 2008—As Adjusted” under the caption “Capitalization.” Except as disclosed in the Registration Statement, the Disclosure Package and the Prospectus, there are no outstanding (A) securities or obligations of the Company or any of the Subsidiaries convertible into or exchangeable for any equity interests of the Company or any such Subsidiary, (B) warrants, rights or options to subscribe for or purchase from the Company or any such Subsidiary any such equity interests or any such convertible or exchangeable securities or obligations or (C) obligations of the Company or any such Subsidiary to issue any equity interests, any such convertible or exchangeable securities or obligation, or any such warrants, rights or options.

(ix) Authorization and Description of Certain Agreements. This Agreement has been duly authorized, executed and delivered by the Company and is the valid and binding obligation of the Company enforceable in accordance with its terms, and the Management Agreement by and between the Company and the Manager, which is filed as Exhibit 10.2 to the Registration Statement (the “Management Agreement”), has been duly authorized by the Company and at the Closing Time will have been duly executed and delivered by the Company and will constitute a legal, valid and binding agreement of the Company enforceable in accordance with its terms, except in each case as the enforcement thereof may be subject to (A) bankruptcy, insolvency, reorganization, moratorium or other similar laws now or thereafter in effect relating to creditors’ rights generally and (B) general principles of equity and the discretion of the court before which any proceeding therefor may be brought. This Agreement and the Management Agreement conform in all material respects to the descriptions thereof in the Registration Statement, the Disclosure Package and the Prospectus.

(x) Authorization and Description of Securities. The Securities have been duly authorized for issuance and sale to the Underwriters pursuant to this Agreement and, when issued and delivered by the Company pursuant to this Agreement against payment of the consideration set forth herein, will be validly issued and fully paid and non-assessable; the Securities conform in all material respects to all statements relating thereto contained in the Registration Statement, the Disclosure Package and the Prospectus and such descriptions conform in all material respects to the rights set forth in the instruments defining the same; no holder of the Securities will be subject to personal liability by reason of being such a holder; and the issuance of the Securities is not subject to any preemptive or other similar rights of any securityholder of the Company.

(xi) Absence of Defaults and Conflicts. The Company is not in violation of its certificate of incorporation (“Charter”), or its bylaws (“Bylaws”). No Subsidiary is in violation of its organizational documents (including, without limitation, partnership and limited liability

company agreements). Neither the Company nor any Subsidiary is in default in the performance or observance (nor has any event occurred which with notice, lapse of time, or both would constitute a default in the observance or performance) of any obligation, agreement, covenant or condition contained in any contract, indenture, mortgage, deed of trust, loan or credit agreement, note, lease or other agreement or instrument to which the Company is a party or by which it may be bound, or to which any of the property or assets of the Company is subject (collectively, “Agreements and Instruments”). The execution, delivery and performance by the Company of this Agreement and the consummation by the Company of the transactions contemplated herein (including the issuance and sale of the Securities and the use of the proceeds from the sale of the Securities as described in the Registration Statement, the Disclosure Package and the Prospectus under the caption “Use of Proceeds”) and compliance by the Company with its obligations hereunder and thereunder have been duly authorized by all necessary corporate action and do not and will not, whether with or without the giving of notice or passage of time or both, conflict with or constitute a breach of, or default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company pursuant to, the Agreements and Instruments, nor will such action result in any violation of the provisions of the Charter or Bylaws of the Company or the organizational documents of any Subsidiary (including, without limitation, partnership and limited liability company agreements), any applicable law, statute, rule, regulation, judgment, order, writ or decree of any government, government instrumentality or court, domestic or foreign, having jurisdiction over the Company or any Subsidiary or any of their assets, properties or operations.

(xii) Compliance with Applicable Laws, Rules and Regulations. The Company and each of its Subsidiaries are in compliance with all applicable federal, state, local and foreign laws, rules, regulations, orders, decrees and judgments, including those relating to transactions with affiliates, except where the failure to so comply is not reasonably likely to, singly or in the aggregate, result in a Material Adverse Effect.

(xiii) Absence of Proceedings. There is no action, suit, proceeding, inquiry or investigation before or brought by any court or governmental agency or body, domestic or foreign, now pending, or, to the knowledge of the Company, threatened, against or affecting the Company or any Subsidiary, which is required to be disclosed in the Registration Statement, the Disclosure Package or the Prospectus (other than as disclosed therein), or which would reasonably be expected to result in a Material Adverse Effect, or which would reasonably be expected to materially and adversely affect the properties or assets thereof or the consummation of the transactions contemplated in this Agreement or the performance by the Company of its obligations hereunder; the aggregate of all pending legal or governmental proceedings to which the Company or any subsidiary is a party or of which any of their respective property or assets is the subject which are not described in the Registration Statement, including ordinary routine litigation incidental to the business, could not, singly or in the aggregate, result in a Material Adverse Effect.

(xiv) Accuracy of Exhibits. There are no contracts or documents that are required to be described in the Registration Statement, the Disclosure Package or the Prospectus or to be filed as exhibits thereto which have not been described in all material respects and filed as required by Item 601(b) of Regulation S-K of the 1993 Act Regulations. The copies of all contracts, agreements, instruments and other documents (including governmental licenses, authorizations, permits, consents and approvals and all amendments or waivers relating to any of the foregoing) that have been furnished to the Underwriters or their counsel are complete and genuine and include all material collateral and supplemental agreements thereto.

(xv) Possession of Intellectual Property. The Company and its Subsidiaries own or possess, or can acquire on reasonable terms, adequate patents, patent rights, licenses, inventions, copyrights, know how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures), trademarks, service marks, trade names or other intellectual property (collectively, “Intellectual Property”) necessary to carry on the business now operated by them, and neither the Company nor any of its Subsidiaries has received any notice or is otherwise aware of any infringement of or conflict with asserted rights of others with respect to any Intellectual Property or of any facts or circumstances which would render any Intellectual Property invalid or inadequate to protect the interest of the Company or any of its Subsidiaries therein, and which infringement or conflict (if the subject of any unfavorable decision, ruling or finding) or invalidity or inadequacy, singly or in the aggregate, would result in a Material Adverse Effect.

(xvi) Absence of Manipulation. Neither the Company nor any affiliate of the Company has taken, nor will the Company or any affiliate take, directly or indirectly, any action that is designed to, has constituted or which would be expected to cause or result in stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities.

(xvii) Absence of Further Requirements. No filing with, or authorization, approval, consent, license, order, registration, qualification or decree of, any court or governmental authority or agency is necessary or required for the performance by the Company of its obligations hereunder, in connection with the offering, issuance or sale of the Securities hereunder or the consummation of the transactions contemplated by this Agreement, except such as have been already obtained or as may be required under the 1933 Act or the 1933 Act Regulations or state securities laws.

(xviii) Possession of Licenses and Permits. The Company and its Subsidiaries possess such permits, licenses, approvals, consents and other authorizations issued by the appropriate federal, state, local or foreign regulatory agencies or bodies necessary to conduct the business now operated by them as described in the Registration Statement, the Disclosure Package and the Prospectus (collectively, “Intangibles”), except where the failure so to possess is not reasonably likely to, individually or in the aggregate, result in a Material Adverse Effect; the Company and its Subsidiaries are in compliance with the terms and conditions of all such Intangibles, except where the failure so to comply is not reasonably likely to, singly or in the aggregate, result in a Material Adverse Effect; all of the Intangibles are valid and in full force and effect, except when the invalidity of such Intangibles or the failure of such Intangibles to be in full force and effect is not reasonably likely to, singly or in the aggregate, result in a Material Adverse Effect; the Company and its Subsidiaries have not received any notice of proceedings relating to the revocation or modification of any such Intangibles which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would be reasonably likely to, result in a Material Adverse Effect; the Company and its Subsidiaries have not violated or received written notice of any infringement of or conflict with (and the Company does not know of any such infringement of or conflict with) asserted rights of others with respect to any such Intangibles, except where the infringement of or conflict with is not reasonably likely to, singly or in the aggregate, result in a Material Adverse Effect.

(xix) Payment of Taxes. All tax returns of the Company and its Subsidiaries required by law to be filed have been filed and all taxes shown by such returns or otherwise assessed, which are due and payable, have been paid, except assessments against which appeals have been or will be promptly taken as to which adequate reserves have been provided. The charges,

accruals and reserves on the books of the Company in respect of any income and corporation tax liability for any years not finally determined are adequate to meet any assessments or re-assessments for additional income tax for any years not finally determined, except to the extent of any inadequacy that would not result in a Material Adverse Effect.

(xx) Absence of Transfer Taxes. There are no transfer taxes or other similar fees or charges under federal law or the laws of any state, or any political subdivision thereof, required to be paid in connection with the execution and delivery of this Agreement or the issuance or sale by the Company of the Securities.

(xxi) Foreign Corrupt Practices Act. Neither the Company nor any of its Subsidiaries, nor to the knowledge of the Company, any director, officer, agent, employee, affiliate or other person acting on behalf of the Company or any of its Subsidiaries is aware of or has taken any action, directly or indirectly, that would result in a violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (the “FCPA”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA. The Company, the Subsidiaries and American Capital Strategies, Ltd. (“ACAS”) have conducted their businesses in compliance with the FCPA and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith.

(xxii) Money Laundering Laws. The operations of the Company and its Subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its Subsidiaries with respect to the Money Laundering Laws is pending or, to the best knowledge of the Company, threatened.

(xxiii) OFAC. Neither the Company nor any of its Subsidiaries, nor to the knowledge of the Company, any director, officer, agent, employee, affiliate or person acting on behalf of the Company or any of its Subsidiaries is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Treasury Department (“OFAC”); and the Company will not directly or indirectly use the proceeds of the offering, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

(xxiv) Related Party Transactions. No relationship, direct or indirect, exists between or among the Company or any of its Subsidiaries on the one hand, and the directors, officers, trustees, managers, stockholders, partners, customers or suppliers of the Company or any of the Subsidiaries on the other hand, which would be required by the 1933 Act or by the 1933 Regulations to be described in the Registration Statement, the Disclosure Package and the Prospectus, which is not so described.

(xxv) Noncompetition; nondisclosure. Neither the Company nor any officer of the Company is subject to any noncompete, nondisclosure, confidentiality, employment, consulting or similar arrangement that would be violated by the present or proposed business activities of the Company as described in the Registration Statement, the Disclosure Package and the Prospectus.

(xxvi) Investment Company Act. The Company is not required, and upon the issuance and sale of the Securities as herein contemplated and the application of the net proceeds therefrom as described in the Registration Statement, the Disclosure Package and the Prospectus will not be required, to register as an “investment company” under the Investment Company Act of 1940, as amended (the “1940 Act”).

(xxvii) Registration Rights. Except as disclosed in the Registration Statement, the Disclosure Package, and the Prospectus, there are no persons with registration or other similar rights to have any equity or debt securities, including securities that are convertible into or exchangeable for equity securities, registered pursuant to the Registration Statement or otherwise registered by the Company under the 1933 Act; and no person has a right of participation or first refusal with respect to the sale of the securities by the Company.

(xxviii) Accounting Controls and Disclosure Controls. The Company and each of its Subsidiaries maintain a system of internal accounting controls sufficient to provide reasonable assurances that (A) transactions are executed in accordance with management’s general or specific authorization; (B) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain accountability for assets; (C) receipts and expenditures are being made only in accordance with management’s general or specific authorization; (D) access to assets is permitted only in accordance with management’s general or specific authorization; and (E) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. Except as described in the Registration Statement, the Disclosure Package and the Prospectus, since the Company’s inception, there has been (1) no material weakness in the Company’s internal control over financial reporting (whether or not remediated) and (2) no change in the Company’s internal control over financial reporting that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting. The Company and its Subsidiaries have established disclosure controls and procedures that are designed to ensure that information required to be disclosed by the Company in the reports that it files or submits under the 1934 Act is recorded, processed, summarized and reported, within the time periods specified in the Commission’s rules and forms, and is accumulated and communicated to the Company’s management, including its principal executive officer or officers and principal financial officer or officers, as appropriate, to allow timely decisions regarding disclosure.

(xxix) Compliance with the Sarbanes-Oxley Act. The Company has taken all necessary actions to ensure that, upon the effectiveness of the Registration Statement, it will be in compliance in all material respects with all provisions of the Sarbanes-Oxley Act of 2002 and all rules and regulations promulgated thereunder or implementing the provisions thereof (the “Sarbanes-Oxley Act of 2002”) that are then in effect and which the Company is required to comply with as of the effectiveness of the Registration Statement.

(xxx) Pending Proceedings and Examinations. The Registration Statement is not the subject of a pending proceeding or examination under Section 8(d) or 8(e) of the 1933 Act, and the Company is not the subject of a pending proceeding under Section 8A of the 1933 Act in connection with the offering of the Securities.

(xxxi) REIT Status. Commencing with its initial taxable year ending December 31, 2008, the Company has been organized in conformity with the requirements for qualification and taxation as a real estate investment trust (“REIT”) under the Internal Revenue Code of 1986, as amended, and the regulations and published interpretations thereunder (collectively, the “Code”), and the Company’s proposed method of operation (taking into account its operations to date) as described in the Registration Statement, the Disclosure Package and the Prospectus will enable it to meet the requirements for qualification and taxation as a REIT under the Code. No transaction or other event has occurred that could cause the Company to not be able to qualify as a REIT for its taxable year ending December 31, 2008 or future taxable years. The Company and each of its Subsidiaries have no intention of changing their operations or engaging in activities that would cause the Company to fail to qualify, or make economically undesirable the Company’s continued qualification as a REIT.

(xxxii) Tax Opinion. The Company’s representatives have discussed with its counsel, Skadden, Arps, Slate, Meagher & Flom LLP, the officer’s certificate supporting the legal opinion as to certain tax matters provided pursuant to Section 5(b) hereof, and where representations in such officer’s certificate involve terms defined in the Code, the Treasury regulations thereunder, published rulings of the Internal Revenue Service, or other relevant authority, the Company’s representatives are satisfied after their discussions with their counsel in their understanding of such terms and are capable of making such representations.

(xxxiii) Description of Organization and Method of Operation. The description of the Company’s organization and proposed method of operation and its qualification and taxation as a REIT set forth in the Registration Statement, the Disclosure Package and the Prospectus is accurate in all material respects and presents fairly the matters referred to therein. The Company’s conflicts of interest, operating policies, investment guidelines and operating restrictions described in the Registration Statement, the Disclosure Package and the Prospectus accurately reflect in all material respects the current intentions of the Company with respect to the operation of its business, and no material deviation from such guidelines or policies is currently contemplated.

(xxxiv) Director Independence. Each of the independent director nominees (or independent directors once appointed) named in the Registration Statement, the Disclosure Package and Prospectus satisfies the independence standards established by The NASDAQ Stock Market, Inc. (“NASDAQ”) and the enhanced independence standards contained in Rule 10A-3(b)(1) promulgated by the Commission under the 1934 Act.

(xxxv) Broker/Dealer Status. Neither the Company nor any of its affiliates (i) is required to register as a “broker” or “dealer” in accordance with the provisions of the rules and regulations promulgated under 1934 Act (the “1934 Act Regulations”), or (ii) directly, or indirectly through one or more intermediaries, controls or has any other association with (within the meaning of Article I of the By-laws of the Financial Industry Regulatory Authority, Inc. (the “FINRA”)) any member firm of the FINRA. No relationship, direct or indirect, exists between or among the Company, on the one hand, and the directors, officers or stockholders of the Company, on the other hand, which is required by the rules of the FINRA to be described in the Registration Statement, the Disclosure Package and the Prospectus, which is not so described.

(xxxvi) Finder’s Fees. Except for the Underwriters’ discount, the Company has not incurred any liability for any finder’s fees or similar payments in connection with the transactions herein contemplated.

(xxxvii) Insurance. The Company and its Subsidiaries carry or are entitled to the benefits of insurance, with financially sound and reputable insurers, in such amounts and covering such risks as is generally maintained by companies of established repute engaged in the same or similar business, which do not own or lease any property or have any employees, and all such insurance is in full force and effect. The Company has no reason to believe that it or any Subsidiary will not be able (A) to renew its existing insurance coverage as and when such policies expire or (B) to obtain comparable coverage from similar institutions as may be necessary or appropriate to conduct its business as now conducted and at a cost that would not result in a Material Adverse Effect. Neither the Company nor any Subsidiary has been denied any insurance coverage which it has sought or for that it has applied.

(xxxviii) Dividends/Distributions. Except as disclosed in the Registration Statement, the Disclosure Package and the Prospectus, no Subsidiary is currently prohibited, directly or indirectly, from paying any dividends or distributions to the Company to the extent permitted by applicable law, from making any other distribution on such Subsidiary’s issued and outstanding capital stock or other equity interests, from repaying to the Company any loans or advances to such Subsidiary from the Company or from transferring any of the property or assets of such Subsidiary to the Company.

(xxxix) Market Data. The statistical and market related data included in the Registration Statement, the Disclosure Package and the Prospectus are based on or derived from current sources that the Company believes to be reliable and accurate.

(xl) ACAS Data. The financial and other data of ACAS included in the Registration Statement, the Disclosure Package and the Prospectus is true, complete and accurate in all material respects.

(xli) Stock Option Grants. No stock option awards have been granted by the Company.

(xlii) Environmental Compliance. The Company is not in violation of, and has not received notice of any violation with respect to, any applicable environmental, safety or similar law applicable to the business of the Company. The Company has received all permits, licenses or other approvals required of it under applicable federal and state occupational safety and health and environmental laws and regulations to conduct its business, and the Company is in compliance with all terms and conditions of any such permit, license or approval, except any such violation of law or regulation, failure to receive required permits, licenses or other approvals or failure to comply with the terms and conditions of such permits, licenses or approvals, which could not, singly or in the aggregate, have a Material Adverse Effect.

(xliii) Real Property; Personal Property. The Company and the Subsidiaries have good and marketable title in fee simple to all real property, if any, and good title to all personal property, if any, owned by it, in each case free and clear of all liens, security interests, pledges, charges, encumbrances, mortgages and defects, except as are disclosed in the Registration Statement, the Disclosure Package and the Prospectus or as could not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect; any real property or personal property held under lease by the Company or any of the Subsidiaries is held under a lease that is valid, existing and enforceable against the Company or such Subsidiary, with such exceptions as are disclosed in the Registration Statement, the Disclosure Package and the Prospectus or as could not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(xliv) Lending Relationships. Except as disclosed in the Registration Statement, the Disclosure Package and the Prospectus, neither the Company nor ACAS has any material lending or other relationship with any bank or lending affiliate of any Underwriter.

(b) Representations and Warranties by the Manager. The Manager represents and warrants to each Underwriter as of the date hereof as of the Applicable Time, as of the Closing Time, and, as of each such Date of Delivery (if any) and agrees with each Underwriter, as follows:

(i) Registration Statement, Prospectus and Disclosure Package at Time of Sale. At the respective times the Registration Statement, any Rule 462(b) Registration Statement and each amendment thereto became effective and at the Closing Time (and, if any Option Securities are purchased, at the Date of Delivery), the Registration Statement, any Rule 462(b) Registration Statement and any amendments and supplements thereto complied and will comply in all material respects with the requirements of the 1933 Act and the 1933 Act Regulations and did not and will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading.

As of the Applicable Time and as of the Closing Time, neither (x) the Disclosure Package, nor (y) any individual Issuer Limited Use Free Writing Prospectus, when considered together with the Disclosure Package, included any untrue statement of a material fact or omitted to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(ii) Good Standing of the Manager. The Manager has been duly formed and is validly existing as a limited liability company in good standing under the laws of the State of Delaware and has power and authority to own, lease and operate its properties and to conduct its business as described in the Registration Statement, the Disclosure Package and the Prospectus and to enter into and perform its obligations under this Agreement; and the Manager is duly qualified as a foreign limited liability company to transact business and is in good standing in each other jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except where the failure so to qualify or to be in good standing would not result in a Material Adverse Effect.

(iii) Authorization of Certain Agreements. This Agreement has been duly authorized, executed and delivered by the Manager and constitutes a valid and binding agreement of the Manager enforceable in accordance with its terms, and each of the Management Agreement and the Administrative Services Agreement to be entered into by ACAS and the Manager (the “Services Agreement”) has been duly authorized by the Manager and at the Closing Time will have been duly executed and delivered by the Manager and will constitute a legal, valid and binding agreement of the Manager enforceable in accordance with its terms, except in ease case as may be limited by (A) bankruptcy, insolvency, reorganization, moratorium or other similar laws now or thereafter in effect relating to creditors’ rights generally and (B) general equitable principles and the discretion of the court before which any proceeding therefor may be brought.

(iv) Absence of Defaults and Conflicts. Neither the Manager nor ACAS is in violation of their respective organizational documents or in default in the performance or observance of any obligation, agreement, covenant or condition contained in any contract, indenture, mortgage, deed of trust, loan or credit agreement, note, lease or other agreement or instrument to which the Manager or ACAS is a party or by which it may be bound, or to which any of the property or assets of the Manager or ACAS is subject (collectively, the “Manager Agreements and Instruments”), or in violation of any law, statute, rule, regulation, judgment, order or decree, except for such violations or except for such defaults that would not result in a material adverse effect on the condition, financial or otherwise, or in the business affairs, business prospects or regulatory status of the Manager, whether or not arising in the ordinary course of business, or that would otherwise prevent the Manager from carrying out its obligations under this Agreement (a “Manager Material Adverse Effect”). The execution, delivery and performance of this Agreement and the consummation of the transactions contemplated herein and in the Registration Statement, the Disclosure Package and the Prospectus and compliance by the Manager with its obligations under this Agreement do not and will not, whether with or without the giving of notice or passage of time or both, conflict with or constitute a breach of, or default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Manager or ACAS pursuant to the Manager Agreements and Instruments, nor will such action result in any violation of the provisions of the limited liability company operating agreement of the Manager or other organizational documents, the organizational documents of ACAS or any applicable law, statute, rule, regulation, judgment, order, writ or decree of any government, government instrumentality or court, domestic or foreign, having jurisdiction over the Manager or any of its assets, properties or operations.

(v) Absence of Proceedings. There is no action, suit, proceeding, inquiry or investigation before or brought by any court or governmental agency or body, domestic or foreign, now pending, or, to the knowledge of the Manager, threatened, against or affecting the Manager.

(vi) Absence of Further Requirements. (A) No filing with, or authorization, approval, consent, license, order, registration, qualification or decree of, any court or governmental authority or agency, domestic or foreign, (B) no authorization, approval, vote or other consent of any stockholder or creditor of the Manager, (C) no waiver or consent under any Manager Agreements and Instruments, and (D) no authorization, approval, vote or other consent of any other person or entity, is necessary or required for the performance by the Manager of its obligations under this Agreement and the transactions contemplated hereby, in each case on the terms contemplated by the Registration Statement, the Disclosure Package and the Prospectus,

except (1) such as have been already obtained or as may be required under the 1933 Act or the 1933 Act Regulations or state securities laws and (2) such, the failure of which to have obtained, would not reasonably be expected to have a Manager Material Adverse Effect.

(vii) Financial Resources. Upon the execution of the Services Agreement by ACAS and the Manager, the Manager will have the financial and other resources available to it necessary for the performance of its services and obligations as contemplated in the Registration Statement, the Disclosure Package and the Prospectus and under this Agreement.

(viii) Possession of Licenses and Permits. The Manager possesses such Intangibles issued by the appropriate federal, state, local or foreign regulatory agencies or bodies necessary to conduct its business as described in the Registration Statement, the Disclosure Package and the Prospectus, except where the failure so to possess would not, individually or in the aggregate, result in a Material Adverse Effect or a Manager Material Adverse Effect; the Manager is in compliance with the terms and conditions of all such Intangibles, except where the failure so to comply would not, individually or in the aggregate, result in a Material Adverse Effect or a Manager Material Adverse Effect; all of the Intangibles are valid and in full force and effect, except when the invalidity of such Intangibles or the failure of such Intangibles to be in full force and effect would not have a Material Adverse Effect or a Manager Material Adverse Effect; and the Manager has not received any notice of proceedings relating to the revocation or modification of any such Intangibles which, individually or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would result in a Material Adverse Effect or a Manager Material Adverse Effect.

(ix) Employment; Noncompetition; Nondisclosure. The Manager has not been notified that any executive officer of the Company or the Manager or key member or significant number of members of ACAS’s residential mortgage investment team plans to terminate its or their employment with ACAS. Neither the Manager nor, any executive officer or key employee of the Company or the Manager or key member of ACAS’s residential mortgage investment team is subject to any noncompete, nondisclosure, confidentiality, employment, consulting or similar agreement that would be violated by the present or proposed business activities of the Company or the Manager as described in the Registration Statement, the Disclosure Package and the Prospectus, except where such violation would not constitute a Manager Material Adverse Effect.

(x) Internal Controls. The Manager operates a system of internal controls sufficient to provide reasonable assurance that (A) transactions that may be effectuated by it under the Management Agreement are executed in accordance with its management’s general or specific authorization; and (B) access to the Manager’s assets is permitted only in accordance with its management’s general or specific authorization.

(xi) Manager Data. The information relating to the Manager included in the Registration Statement, the Disclosure Package and the Prospectus is true, complete and accurate in all material respects.

(xii) Investment Advisers Act. The Manager is not prohibited by the Investment Advisers Act of 1940, as amended (the “Advisers Act”), or the rules and regulations thereunder, from performing its obligations under the Management Agreement as described in the Registration Statement, the Disclosure Package and the Prospectus; and the Manager is not registered and is not required to register as an investment adviser under the Advisers Act.

(c) Officer’s Certificates. Any certificate signed by any officer of the Company or the Manager delivered to the Representatives or to counsel for the Underwriters pursuant to this Agreement shall be deemed a representation and warranty by the Company or the Manager, as the case may be, to each Underwriter as to the matters covered thereby.

(a) Initial Securities. On the basis of the representations and warranties herein contained and subject to the terms and conditions herein set forth, the Company agrees to sell to each Underwriter, severally and not jointly, and each Underwriter, severally and not jointly, agrees to purchase from the Company, at the price per share of Common Stock of $20.00, the number of Initial Securities set forth in Schedule I opposite the name of such Underwriter, plus any additional number of Initial Securities which such Underwriter may become obligated to purchase pursuant to the provisions of Section 10 hereof, bears to the total number of Initial Securities, subject, in each case, to such adjustments among the Underwriters as the Representatives in their sole discretion shall make to eliminate any sales or purchases of fractional securities.

(b) Option Securities. In addition, on the basis of the representations and warranties herein contained and subject to the terms and conditions herein set forth, the Company hereby grants an option to the Underwriters, severally and not jointly, to purchase up to an additional 1,875,000 shares of Common Stock, at the price per share set forth in paragraph (a) above. The option hereby granted will expire 30 days after the date hereof and may be exercised in whole or in part from time to time only for the purpose of covering overallotments which may be made in connection with the offering and distribution of the Initial Securities upon notice by the Representatives to the Company setting forth the number of Option Securities as to which the several Underwriters are then exercising the option and the time and date of payment and delivery for such Option Securities. Any such time and date of delivery (a “Date of Delivery”) shall be determined by the Representatives, but shall not be later than seven full business days after the exercise of said option, nor in any event prior to the Closing Time, as hereinafter defined. If the option is exercised as to all or any portion of the Option Securities, each of the Underwriters, acting severally and not jointly, will purchase that proportion of the total number of Option Securities then being purchased which the number of Initial Securities set forth in Schedule I opposite the name of such Underwriter bears to the total number of Initial Securities, subject in each case to such adjustments as the Representatives in their sole discretion shall make to eliminate any sales or purchases of fractional shares.

(c) Payment. Payment of the purchase price for, and delivery of certificates, if any, for the Initial Securities shall be made at the offices of Skadden, Arps, Slate, Meagher & Flom LLP, Four Times Square, New York, New York 10036, or at such other place as shall be agreed upon by the Representatives and the Company, at 10:00 a.m. (New York City time) on May __, 2008 (unless postponed in accordance with the provisions of Section 10), or such other time not later than ten business days after such date as shall be agreed upon by the Representatives and the Company (such time and date of payment and delivery being herein called “the Closing Time”).

In addition, in the event that any or all of the Option Securities are purchased by the Underwriters, payment of the purchase price for, and delivery of certificates for, such Option Securities shall be made at the above-mentioned offices, or at such other place as shall be agreed upon by the Representatives and the Company, on each Date of Delivery as specified in the notice from the Representatives to the Company.

Payment shall be made to the Company by wire transfer of immediately available funds to a bank account designated by the Company against delivery to the Representatives for the respective

accounts of the Underwriters of certificates for the Securities to be purchased by them. It is understood that each Underwriter has authorized the Representatives, for its account, to accept delivery of, receipt for, and make payment of the purchase price for, the Initial Securities and the Option Securities, if any, which it has agreed to purchase. Any Representatives, individually and not as representatives of the Underwriters, may (but shall not be obligated to) make payment of the purchase price for the Initial Securities or the Option Securities, if any, to be purchased by any Underwriter whose funds have not been received by the Closing Time or the relevant Date of Delivery, as the case may be, but such payment shall not relieve such Underwriter from its obligations hereunder.

(d) Denominations; Registration. Certificates for the Initial Securities and the Option Securities, if any, shall be in such denominations and registered in such names as the Representatives may request in writing at least one full business day before the Closing Time or the relevant Date of Delivery, as the case may be. The certificates for the Initial Securities and the Option Securities, if any, will be made available for examination and packaging by the Representatives in the City of New York not later than 10:00 a.m. (New York City time) on the business day prior to the Closing Time or the relevant Date of Delivery, as the case may be.

SECTION 3. Covenants of the Company. The Company covenants with each Underwriter as follows:

(a) Compliance with Securities Regulations and Commission Requests. The Company, subject to Section 3(b) hereof, will comply with the requirements of Rule 430A and will notify the Representatives promptly, and confirm the notice in writing, (i) when any post-effective amendment to the Registration Statement shall become effective, or any supplement to the Prospectus or any amended Prospectus shall have been filed, (ii) of the receipt of any comments from the Commission, (iii) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or any document deemed to be a part thereof or for additional information, (iv) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or of any order preventing or suspending the use of any preliminary prospectus, or of the suspension of the qualification of the Securities for offering or sale in any jurisdiction, or of the initiation or threatening of any proceedings for any of such purposes or of any examination pursuant to Section 8(e) of the 1933 Act concerning the Registration Statement and (v) if the Company becomes the subject of a proceeding under Section 8A of the 1933 Act in connection with the offering of the Securities. The Company will effect the filings required under Rule 424(b), in the manner and within the time period required by Rule 424(b) (without reliance on Rule 424(b)(8) of the 1933 Act Regulations) and will take such steps as it deems necessary to ascertain promptly whether the form of prospectus transmitted for filing under Rule 424(b) was received for filing by the Commission and, in the event that it was not, it will promptly file such prospectus. The Company will make every reasonable effort to prevent the issuance of any stop order and, if any stop order is issued, to obtain the lifting thereof at the earliest possible moment.

(b) Filing of Amendments and Exchange Act Documents. The Company will give the Representatives notice of its intention to file or prepare any amendment to the Registration Statement (including any filing under Rule 462(b)) or any amendment, supplement or revision to either any preliminary prospectus (including any preliminary prospectus included in the Registration Statement or any amendment thereto at the time it became effective) or to the Prospectus, whether pursuant to the 1933 Act, the 1934 Act or otherwise, and the Company will furnish the Representatives with copies of any such documents a reasonable amount of time prior to such proposed filing or use, as the case may be, and will not file or use any such document to which the Representatives or counsel for the Underwriters shall reasonably object. The Company has given the Representatives notice of its intention to make any filings pursuant to the 1934 Act or the 1934 Act Regulations from the Applicable Time to the Closing Time and

will furnish the Representatives with copies of any such documents a reasonable amount of time prior to such proposed filing and will not file or use any such document to which the Representatives or counsel for the Underwriters shall reasonably object.

(c) Delivery of Registration Statements. The Company has furnished or will deliver to the Representatives and counsel for the Underwriters, without charge, conformed copies of the Registration Statement as originally filed and of each amendment thereto (including exhibits filed therewith and documents deemed to be a part thereof) and conformed copies of all consents and certificates of experts, and will also deliver to the Representatives, without charge, a conformed copy of the Registration Statement as originally filed and of each amendment thereto (without exhibits) for each of the Underwriters. The copies of the Registration Statement and each amendment thereto furnished to the Underwriters will be identical to the electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T.

(d) Delivery of Prospectuses. The Company has delivered to each Underwriter, without charge, as many copies of each preliminary prospectus as such Underwriter reasonably requested, and the Company hereby consents to the use of such copies for purposes permitted by the 1933 Act. The Company will furnish to each Underwriter, without charge, during the period when the Prospectus is required to be delivered under the 1933 Act, such number of copies of the Prospectus (as amended or supplemented) as such Underwriter may reasonably request. The Prospectus and any amendments or supplements thereto furnished to the Underwriters will be identical to the electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T.

(e) Continued Compliance with Securities Laws. The Company will comply with the 1933 Act and the 1933 Act Regulations and the 1934 Act and the 1934 Act Regulations so as to permit the completion of the distribution of the Securities as contemplated in this Agreement and in the Prospectus. If at any time when a prospectus is required by the 1933 Act to be delivered in connection with sales of the Securities, any event shall occur or condition shall exist as a result of which it is necessary, in the opinion of counsel for the Underwriters or for the Company, to amend the Registration Statement or amend or supplement the Prospectus in order that the Prospectus will not include any untrue statements of a material fact or omit to state a material fact necessary in order to make the statements therein not misleading in the light of the circumstances existing at the time it is delivered to a purchaser, or if it shall be necessary, in the opinion of such counsel, at any such time to amend the Registration Statement or amend or supplement the Prospectus in order to comply with the requirements of the 1933 Act or the 1933 Act Regulations, the Company will promptly prepare and file with the Commission, subject to Section 3(b) hereof, such amendment or supplement as may be necessary to correct such statement or omission or to make the Registration Statement or the Prospectus comply with such requirements, the Company will use its best efforts to have such amendment declared effective as soon as practicable and the Company will furnish to the Underwriters such number of copies of such amendment or supplement as the Underwriters may reasonably request. If at any time following issuance of an Issuer Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer Free Writing Prospectus conflicted or would conflict with the information contained in the Registration Statement (or any other registration statement relating to the Securities) or the Statutory Prospectus or any preliminary prospectus or included or would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances prevailing at that subsequent time, not misleading, the Company will promptly notify the Representatives and will promptly amend or supplement, at its own expense, such Issuer Free Writing Prospectus to eliminate or correct such conflict, untrue statement or omission.

(f) Blue Sky Qualifications. The Company will use its best efforts, in cooperation with the Underwriters, to qualify the Securities for offering and sale under the applicable securities laws of such

states and other jurisdictions as the Representatives may designate and to maintain such qualifications in effect for a period of not less than one year from the date hereof; provided, however, that the Company shall not be obligated to file any general consent to service of process or to qualify as a foreign corporation or as a dealer in securities in any jurisdiction in which it is not so qualified or to subject itself to taxation in respect of doing business in any jurisdiction in which it is not otherwise so subject.

(g) Rule 158. The Company will timely file such reports pursuant to the 1934 Act as are necessary in order to make generally available to its securityholders as soon as practicable an earnings statement for the purposes of, and to provide to the Underwriters the benefits contemplated by, the last paragraph of Section 11(a) of the 1933 Act.

(h) Use of Proceeds. The Company will use the net proceeds received by it from the sale of the Securities in the manner specified in the Disclosure Package and the Prospectus under “Use of Proceeds.”

(i) Listing. The Company will use its best efforts to maintain the listing of the Securities on The NASDAQ Global Market of NASDAQ and to file with NASDAQ all documents and notices required by NASDAQ of companies that have securities that are listed on The NASDAQ Global Market.

(j) Restriction on Sale of Securities. During a period of 180 days from the date of the Prospectus, the Company will not, without the prior written consent of the Representatives, (i) directly or indirectly, offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase or otherwise transfer or dispose of any shares of Common Stock or any securities convertible into or exercisable or exchangeable for shares of Common Stock or file any registration statement under the 1933 Act with respect to any of the foregoing or (ii) enter into any swap or any other agreement or any transaction that transfers, in whole or in part, directly or indirectly, the economic consequence of ownership of the shares of Common Stock, whether any such swap or transaction described in clause (i) or (ii) above is to be settled by delivery of shares of Common Stock or such other securities, in cash or otherwise. The foregoing sentence shall not apply to the (A) Securities to be sold hereunder, (B) the 2,500,000 shares of Common Stock to be issued by the Company to ACAS at the Closing Time, (C) any shares of Common Stock issued or options to purchase Common Stock granted pursuant to existing employee benefit plans of the Company, (D) any shares of Common Stock issued pursuant to any non-employee director stock plans or dividend reinvestment plans or (E) any shares of Common Stock issued in mergers and acquisition transactions. Notwithstanding the foregoing, if (1) during the last 17 days of the 180-day restricted period the Company issues an earnings release or material news or a material event relating to the Company occurs or (2) prior to the expiration of the 180-day restricted period, the Company announces that it will release earnings results or becomes aware that material news or a material event will occur during the 16-day period beginning on the last day of the 180-day restricted period, the restrictions imposed in this paragraph (j) shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.

(k) Issuer Free Writing Prospectuses. Each of the Company and the Manager represents and agrees that, unless it obtains the prior consent of the Representatives, and each Underwriter represents and agrees that, unless it obtains the prior consent of the Company, the Manager and the Representatives, it has not made and will not make any offer relating to the Securities that would constitute an “issuer free writing prospectus,” as defined in Rule 433, or that would otherwise constitute a “free writing prospectus,” as defined in Rule 405, required to be filed with the Commission, whether or not required to be filed with the Commission. Any such free writing prospectus consented to by the Company, the Manager and the Representatives is hereinafter referred to as a “Permitted Free Writing Prospectus.” Each of the Company and the Manager represents that it has treated or agrees that it will treat each

Permitted Free Writing Prospectus as an “issuer free writing prospectus,” as defined in Rule 433, and has complied and will comply with the requirements of Rule 433 applicable to any Permitted Free Writing Prospectus, including timely filing with the Commission where required, legending and record keeping.

(l) Share Price Manipulation. Each of the Company and the Manager agrees that it will not, and will cause their respective officers, directors (and in the case of the Manager, American Capital, LLC, ACAS and its subsidiaries) not to, take, directly or indirectly, any action designed to, or that might be reasonably expected to, cause or result in stabilization or manipulation of the price of the Securities to facilitate the sale or resale of the Securities.

(m) REIT Qualification. The Company will use its best efforts to meet the requirements for qualification and taxation as a REIT under the Code for its taxable year ending December 31, 2008 and, subject to any future determination by the Company’s board of directors that it is no longer in the Company’s best interests to qualify as a REIT, thereafter.

(n) Investment Company Act. The Company will use its best efforts to conduct its affairs and the affairs of its Subsidiaries in such a manner so as to ensure that neither the Company nor any of its Subsidiaries will be an “investment company” (as defined in the 1940 Act) or an entity “controlled” by an investment company that is required to be registered under the 1940 Act.

(o) Lock-up Agreements. The Company will use its best efforts to provide the Representatives, prior to the Applicable Time, with (i) an agreement substantially in the form of Exhibit B hereto signed by each of the persons and entities listed on Schedule V hereto and (ii) an agreement substantially in the form of Exhibit D hereto signed by ACAS.

(p) Undertakings. The Company will comply with all of the provisions of any undertakings in the Registration Statement.

(q) Transfer Agent. The Company has engaged and will maintain, at its sole expense, a registrar and transfer agent for the Securities.

(r) Liability Insurance. The Company will obtain or maintain, as appropriate, Directors and Officers liability insurance in an amount deemed advisable by the Company in its reasonable discretion.

(a) Expenses. The Company will pay or cause to be paid all expenses incident to the performance of its obligations under this Agreement, including (i) the preparation, printing and filing of the Registration Statement (including financial statements and exhibits) as originally filed and of each amendment thereto, (ii) the preparation, printing and delivery to the Underwriters of this Agreement, any Agreement among Underwriters and such other documents as may be required in connection with the offering, purchase, sale, issuance or delivery of the Securities, (iii) the preparation, issuance and delivery of the certificates for the Securities to the Underwriters, including any stock or other transfer taxes and any stamp or other duties payable upon the sale, issuance or delivery of the Securities to the Underwriters, (iv) the fees and disbursements of the Company’s counsel, accountants and other advisors, (v) the qualification of the Securities under securities laws in accordance with the provisions of Section 3(f) hereof, including filing fees and the reasonable fees and disbursements of counsel for the Underwriters in connection therewith and in connection with the preparation of any Blue Sky Survey and any supplement thereto, (vi) the printing and delivery to the Underwriters of copies of each preliminary prospectus, any Permitted Free Writing Prospectus and of the Prospectus and any amendments or supplements thereto and any costs associated with electronic delivery of any of the foregoing by the Underwriters to investors,

(vii) the preparation, printing and delivery to the Underwriters of copies of the Blue Sky Survey and any supplement thereto, (viii) the fees and expenses of any transfer agent or registrar for the Securities, (ix) travel and lodging expenses of the officers and representatives (other than the Underwriters) of the Company in connection with the road show, (x) the filing fees incident to, and the reasonable fees and disbursements of counsel to the Underwriters in connection with, the review by the FINRA of the terms of the sale of the Securities, (xi) the fees and expenses incurred in connection with the listing of the Securities on The NASDAQ Global Market, and (xii) the costs and expenses (including without limitation any damages or other amounts payable in connection with legal or contractual liability) associated with the reforming of any contracts for sale of the Securities made by the Underwriters caused by a breach of the representation contained in the fifth paragraph of Section 1(a)(ii) hereof. Except as provided in Section 4, Section 6 and Section 7, hereof, the Underwriters shall pay their own expenses, including the fees and disbursements of their legal counsel and all costs and expenses incident to the preparation and undertaking of the road show presentations to be made to prospective investors, except the expenses described in clause (ix) of this Section 4(a) .

(b) Termination of Agreement. If this Agreement is terminated by the Representatives in accordance with the provisions of Section 5 or Section 9(a)(i), the Company shall reimburse the Underwriters for all reasonable out-of-pocket expenses (including the reasonable fees and disbursements of counsel for the Underwriters) incurred in connection with the proposed purchase and the public offering and sale of the Securities.

SECTION 5. Conditions of Underwriters’ Obligations. The obligations of the several Underwriters hereunder are subject to the accuracy of the representations and warranties of the Company and the Manager contained in Section 1 hereof or in certificates of any officer of the Company or the Manager delivered pursuant to the provisions hereof, to the performance by the Company of its covenants and other obligations hereunder, and to the following further conditions:

(a) Effectiveness of Registration Statement and Filing of Prospectus. The Registration Statement, including any Rule 462(b) Registration Statement, has become effective and at the Closing Time no stop order suspending the effectiveness of the Registration Statement shall have been issued under the 1933 Act or proceedings therefor initiated or threatened by the Commission, and any request on the part of the Commission for additional information shall have been complied with to the reasonable satisfaction of counsel to the Underwriters. A prospectus containing the Rule 430A Information shall have been filed with the Commission in the manner and within the time period required by Rule 424(b) without reliance on Rule 424(b)(8) (or a post-effective amendment providing such information shall have been filed and become effective in accordance with the requirements of Rule 430A).

(b) Opinion of Counsel for Company. At the Closing Time, the Representatives shall have received the favorable opinions, dated as of the Closing Time, from Skadden, Arps, Slate, Meagher & Flom LLP, counsel for the Company and the Manager, in the form and substance satisfactory to counsel for the Underwriters, to the effect set forth in Exhibit A and Exhibit C hereto and to such further effect as counsel to the Underwriters may reasonably request. Such counsel may also state that, insofar as such opinion involves factual matters, they have relied, to the extent they deem proper, upon certificates of officers of the Company and the Manager and certificates of public officials.

(c) Opinion of Counsel for Underwriters. At the Closing Time, the Representatives shall have received the favorable opinion, dated as of the Closing Time, of Hunton & Williams LLP, special counsel for the Underwriters, with respect to the matters as the Underwriters may reasonably request. Such counsel may also state that, insofar as such opinion involves factual matters, they have relied, to the extent they deem proper, upon certificates of officers of the Company and the Manager and certificates of public officials.

(d) Officers’ Certificate. At the Closing Time, there shall not have been, since the date hereof or since the respective dates as of which information is given in the Disclosure Package or the Prospectus, any material adverse change in the condition, financial or otherwise, or in the earnings, business affairs or business prospects of the Company and its Subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business, and the Representatives shall have received a certificate of the President and Chief Executive Officer of the Company and of the Chief Financial Officer of the Company, dated as of the Closing Time, to the effect that (i) there has been no such material adverse change, (ii) the representations and warranties in Section 1(a) hereof are true and correct with the same force and effect as though expressly made at and as of the Closing Time, (iii) the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied at or prior to the Closing Time, and (iv) no stop order suspending the effectiveness of the Registration Statement has been issued and no proceedings for that purpose have been instituted or are pending or, to their knowledge, contemplated by the Commission. The Representatives shall have also received a certificate of the President of the Manager and of the Treasurer of the Manager, dated as of the Closing Time, to the effect that (i) the representations and warranties in Section 1(b) hereof are true and correct with the same force and effect as though expressly made at and as of the Closing Time and (ii) the Manager has complied with all agreements and satisfied all conditions on its part to be performed or satisfied at or prior to the Closing Time.

(e) Accountants’ Comfort Letter. At the time of the execution of this Agreement, the Representatives shall have received from Ernst & Young LLP a letter dated such date, in form and substance satisfactory to the Representatives, together with signed or reproduced copies of such letters for each of the other Underwriters, containing statements and information of the type ordinarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained in the Registration Statement, the Disclosure Package and the Prospectus. Such letters shall address the audited financial statements, any unaudited interim financial statements (including a statement that such unaudited financial statements have been reviewed in accordance with the standards established under Statement on Auditing Standards No. 100) and any pro forma financial statements and also shall provide customary negative assurances.

(f) Bring-down Comfort Letter. At the Closing Time, the Representatives shall have received from Ernst & Young LLP a letter, dated as of the Closing Time, to the effect that Ernst & Young LLP reaffirms the statements made in the letter furnished pursuant to subsection (e) of this Section, except that the specified date referred to shall be a date not more than three business days prior to the Closing Time.

(g) Approval of Listing. At the Closing Time, the Securities shall have been approved for listing on The NASDAQ Global Market, subject only to official notice of issuance.

(h) No Objection. At the Closing Time, the FINRA shall have confirmed that it has not raised any objection with respect to the fairness and reasonableness of the underwriting terms and arrangements.

(i) Lock-up Agreements. At the date of this Agreement, the Representatives shall have received (i) an agreement substantially in the form of Exhibit B hereto signed by the persons and entities listed on Schedule V hereto and (ii) an agreement substantially in the form of Exhibit D hereto signed by ACAS.

(j) Conditions to Purchase of Option Securities. In the event that the Underwriters exercise their option provided in Section 2(b) hereof to purchase all or any portion of the Option Securities, the representations and warranties of the Company and the Manager contained herein and the statements in any certificates furnished by the Company and the Manager hereunder shall be true and correct as of each Date of Delivery and, at the relevant Date of Delivery, the Representatives shall have received:

(i) Officers’ Certificate. A certificate, dated such Date of Delivery, of the Chief Executive Officer and President of the Company and of the Chief Financial Officer of the Company confirming that the certificates delivered at the Closing Time pursuant to Section 5(d) hereof remains true and correct as of such Date of Delivery.

(ii) Officers’ Certificate. A certificate, dated such Date of Delivery, of the President of the Manager and of the Treasurer of the Manager confirming that the certificates delivered at the Closing Time pursuant to Section 5(d) hereof remains true and correct as of such Date of Delivery.

(iii) Opinion of Counsel for Company. The favorable opinion of Skadden, Arps, Slate, Meagher & Flom LLP, counsel for the Company and the Manager, each in form and substance satisfactory to counsel for the Underwriters, dated such Date of Delivery, relating to the Option Securities to be purchased on such Date of Delivery and otherwise to the same effect as the opinions required by Section 5(b) hereof.

(iv) Opinion of Counsel for Underwriters. The favorable opinion of Hunton & Williams LLP, special counsel for the Underwriters, dated such Date of Delivery, relating to the Option Securities to be purchased on such Date of Delivery and otherwise to the same effect as the opinion required by Section 5(c) hereof.

(v) Bring-down Comfort Letter. A letter from Ernst & Young LLP, in form and substance satisfactory to the Representatives and dated such Date of Delivery, substantially in the same form and substance as the letter furnished to the Representatives pursuant to Section 5(e) hereof, except that the “specified date” in the letter furnished pursuant to this paragraph shall be a date not more than three days prior to such Date of Delivery.

(k) Additional Documents. At the Closing Time and at each Date of Delivery counsel for the Underwriters shall have been furnished with such documents and opinions as they may require for the purpose of enabling them to pass upon the issuance and sale of the Securities as herein contemplated, or in order to evidence the accuracy of any of the representations or warranties, or the fulfillment of any of the conditions, herein contained; and all proceedings taken by the Company in connection with the issuance and sale of the Securities as herein contemplated shall be satisfactory in form and substance to the Representatives and counsel for the Underwriters.

(l) Termination of Agreement. If any condition specified in this Section shall not have been fulfilled when and as required to be fulfilled, this Agreement, or, in the case of any condition to the purchase of Option Securities on a Date of Delivery which is after the Closing Time, the obligations of the several Underwriters to purchase the relevant Option Securities, may be terminated by the Representatives by notice to the Company at any time at or prior to the Closing Time or such Date of Delivery, as the case may be, and such termination shall be without liability of any party to any other party, except as provided in Section 4(b) and except that this paragraph and Sections 1, 6, 7 and 8 shall survive any such termination and remain in full force and effect.

(a) Indemnification of Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, as such term is defined in Rule 501(b) under the 1933 Act (each, an “Affiliate”), its selling agents and each person, if any, who controls any Underwriter within the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act as follows:

(i) against any and all loss, liability, claim, damage and expense whatsoever, as incurred, that such Underwriter, its Affiliates, its selling agents and each person, if any, who controls such Underwriter within the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act, may become subject under the 1933 Act, the 1934 Act, the 1940 Act, any U.S. federal or state statutory law or regulation, any Canadian federal or provincial statutory law or regulation or at common law or otherwise, insofar as such loss, liability, claim, damage arises out of or is based on any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement (or any amendment thereto), including the Rule 430A Information, or the omission or alleged omission therefrom of a material fact required to be stated therein or necessary to make the statements therein not misleading or arising out of any untrue statement or alleged untrue statement of a material fact included in any preliminary prospectus (delivered to the Underwriters for use in connection with the offering contemplated by this Agreement, which is dated April 28, 2008), the Disclosure Package, any Issuer Free Writing Prospectus or the Prospectus (or any amendment or supplement thereto), or the omission or alleged omission therefrom of a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading;

(ii) against any and all loss, liability, claim, damage and expense whatsoever, as incurred, to the extent of the aggregate amount paid in settlement of any litigation, or any investigation or proceeding by any governmental agency or body, commenced or threatened, or of any claim whatsoever based upon any such untrue statement or omission, or any such alleged untrue statement or omission; provided that (subject to Section 6(d) below) any such settlement is effected with the written consent of the Company;

(iii) against any and all expense whatsoever, as incurred (including the fees and disbursements of counsel chosen by the Representatives), reasonably incurred in investigating, preparing or defending against any litigation, or any investigation or proceeding by any governmental agency or body, commenced or threatened, or any claim whatsoever based upon any such untrue statement or omission, or any such alleged untrue statement or omission, to the extent that any such expense is not paid under (i) or (ii) above;

provided, however, that this indemnity agreement shall not apply to any loss, liability, claim, damage or expense to the extent arising out of any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives expressly for use in the Registration Statement (or any amendment thereto), including the Rule 430A Information, or any preliminary prospectus, any Issuer Free Writing Prospectus, the Disclosure Package or the Prospectus (or any amendment or supplement thereto).

(b) Indemnification of Company, Directors and Officers. Each Underwriter severally agrees to indemnify and hold harmless the Company, its directors, each of its officers who signed the Registration Statement, and each person, if any, who controls the Company within the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act, against any and all loss, liability, claim, damage and expense described in the indemnity contained in subsection (a) of this Section, as incurred, but only with respect to untrue statements or omissions, or alleged untrue statements or omissions, made in the Registration Statement (or any amendment thereto), including the Rule 430A Information or any preliminary prospectus (delivered to the Underwriters for use in connection with the offering contemplated by this Agreement), Disclosure Package, any Issuer Free Writing Prospectus or the Prospectus (or any amendment or supplement thereto) in reliance upon and in conformity with written

information furnished to the Company by such Underwriter through the Representatives expressly for use therein. The Company hereby acknowledges that the only information that the Underwriters have furnished to the Company expressly for use in the Registration Statement (or any amendment thereto), including the Rule 430A Information or any preliminary prospectus, any Issuer Free Writing Prospectus or the Prospectus (or any amendment or supplement thereto) are the statements set forth under the caption “Underwriting” in the Statutory Prospectus and the Prospectus as follows: paragraph three relating to commissions and discounts, paragraphs 14, 15 and 16 relating to price stabilization and paragraph 19 relating to electronic distribution.

(c) Actions against Parties; Notification. Each indemnified party shall give notice as promptly as reasonably practicable to each indemnifying party of any action commenced against it in respect of which indemnity may be sought hereunder, but failure to so notify an indemnifying party shall not relieve such indemnifying party from any liability hereunder to the extent it is not materially prejudiced as a result thereof and in any event shall not relieve it from any liability which it may have otherwise than on account of this indemnity agreement. In case any such action is brought against any indemnified party and such indemnified party seeks or intends to seek indemnity from an indemnifying party, the indemnifying party will be entitled to participate in, and, to the extent that it shall elect, jointly with all other indemnifying parties similarly notified, by written notice delivered to the indemnified party promptly after receiving the aforesaid notice from such indemnified party, to assume the defense thereof with counsel reasonably satisfactory to such indemnified party; provided, however, if the defendants in any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that a conflict may arise between the positions of the indemnifying party and the indemnified party in conducting the defense of any such action or that there may be legal defenses available to it and/or other indemnified parties that are different from or additional to those available to the indemnifying party, the indemnified party or parties shall have the right to select separate counsel to assume such legal defenses and to otherwise participate in the defense of such action on behalf of such indemnified party or parties. Upon receipt of notice from the indemnifying party to such indemnified party of such indemnifying party’s election so to assume the defense of such action and approval by the indemnified party of counsel, the indemnifying party will not be liable to such indemnified party under this Section 6 for any legal or other expenses subsequently incurred by such indemnified party in connection with the defense thereof unless (i) the indemnified party shall have employed separate counsel in accordance with the proviso to the next preceding sentence (it being understood, however, that the indemnifying party shall not be liable for the expenses of more than one separate counsel (together with local counsel), approved by the indemnifying party (the Representatives in the case of Section 6(b) and Section 10), representing the indemnified parties who are parties to such action), (ii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of commencement of the action, or (iii) the indemnifying party has authorized in writing the employment of counsel for the indemnified party at the expense of the indemnifying party, in each of which cases the fees and expenses of counsel shall be at the expense of the indemnifying party.

(d) Settlement without Consent if Failure to Reimburse. The indemnifying party under this Section 6 shall not be liable for any settlement of any proceeding effected without its written consent, which consent shall not be unreasonably withheld, but if settled with such consent or if there be a final judgment for the plaintiff, the indemnifying party agrees to indemnify the indemnified party against any loss, claim, damage, liability or expense by reason of such settlement or judgment. Notwithstanding the foregoing sentence, if at any time an indemnified party shall have requested an indemnifying party to reimburse the indemnified party for fees and expenses of counsel as contemplated by Section 6(d) hereof, the indemnifying party agrees that it shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than sixty (60) days after receipt by such indemnifying party of the aforesaid request and (ii) such indemnifying party shall not have reimbursed the

indemnified party in accordance with such request prior to the date of such settlement. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement, compromise or consent to the entry of judgment in any pending or threatened action, suit or proceeding in respect of which any indemnified party is or could have been a party and indemnity was or could have been sought hereunder by such indemnified party, unless such settlement, compromise or consent includes (i) an unconditional release of such indemnified party from all liability on claims that are the subject matter of such action, suit or proceeding and (ii) does not include a statement as to or an admission of fault, culpability or a failure to act by or on behalf of any indemnified party.

SECTION 7. Contribution. If the indemnification provided for in Section 6 hereof is for any reason unavailable to or insufficient to hold harmless an indemnified party in respect of any losses, liabilities, claims, damages or expenses referred to therein, then each indemnifying party shall contribute to the aggregate amount of such losses, liabilities, claims, damages and expenses incurred by such indemnified party, as incurred, (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriters on the other hand from the offering of the Securities pursuant to this Agreement or (ii) if the allocation provided by clause (i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company on the one hand and of the Underwriters on the other hand in connection with the statements or omissions which resulted in such losses, liabilities, claims, damages or expenses, as well as any other relevant equitable considerations.

The relative benefits received by the Company on the one hand and the Underwriters on the other hand in connection with the offering of the Securities pursuant to this Agreement shall be deemed to be in the same respective proportions as the total net proceeds from the offering of the Securities pursuant to this Agreement (before deducting expenses) received by the Company and the total underwriting discount received by the Underwriters, in each case as set forth on the cover of the Prospectus bear to the aggregate public offering price of the Securities as set forth on the cover of the Prospectus.

The relative fault of the Company on the one hand and the Underwriters on the other hand shall be determined by reference to, among other things, whether any such untrue or alleged untrue statement of a material fact or omission or alleged omission to state a material fact relates to information supplied by the Company or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 7 were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation which does not take account of the equitable considerations referred to above in this Section 7. The aggregate amount of losses, liabilities, claims, damages and expenses incurred by an indemnified party and referred to above in this Section 7 shall be deemed to include any legal or other expenses reasonably incurred by such indemnified party in investigating, preparing or defending against any litigation, or any investigation or proceeding by any governmental agency or body, commenced or threatened, or any claim whatsoever based upon any such untrue or alleged untrue statement or omission or alleged omission.

Notwithstanding the provisions of this Section 7, no Underwriter shall be required to contribute an amount in excess of the underwriting discounts and commissions applicable to the Securities purchased by such Underwriter and (ii) no person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the 1933 Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations in this Section 7 to contribute are several in proportion to their respective underwriting obligations and not joint.

No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the 1933 Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation.

For purposes of this Section 7, each person, if any, who controls an Underwriter within the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act and each Underwriter’s Affiliates and selling agents shall have the same rights to contribution as such Underwriter, and each director of the Company, each officer of the Company who signed the Registration Statement, and each person, if any, who controls the Company within the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act shall have the same rights to contribution as the Company. The Underwriters’ respective obligations to contribute pursuant to this Section 7 are several in proportion to the number of Initial Securities set forth opposite their respective names in Schedule I hereto and not joint.

SECTION 8. Representations, Warranties and Agreements to Survive. All representations, warranties and agreements contained in this Agreement or in certificates of officers of the Company or the Manager submitted pursuant hereto, shall remain operative and in full force and effect regardless of (a) any investigation made by or on behalf of any Underwriter or its Affiliates or selling agents, any person controlling any Underwriter, its officers or directors or any person controlling the Company and (b) delivery of and payment for the Securities.

(a) Termination; General. The Representatives may terminate this Agreement, by notice to the Company, at any time at or prior to the Closing Time (i) if there has been, since the time of execution of this Agreement or since the respective dates as of which information is given in the Disclosure Package or the Prospectus (exclusive of any supplement thereto), any material adverse change in the condition, financial or otherwise, or in the earnings, business affairs or business prospects of the Company and its Subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business, or (ii) if there has occurred any material adverse change in the financial markets in the United States or the international financial markets, any outbreak of hostilities or escalation thereof or other calamity or crisis or any change or development involving a prospective change in national or international political, financial or economic conditions, as in the judgment of the Representatives is material and adverse and makes it impracticable or inadvisable to market the Securities or to enforce contracts for the sale of the Securities, or (iii) if trading in any securities of the Company has been suspended or materially limited by the Commission or NASDAQ or if trading generally on the New York Stock Exchange or in the NASDAQ has been suspended or materially limited, or minimum or maximum prices for trading have been fixed, or maximum ranges for prices have been required, by any of said exchanges or by such system or by order of the Commission, the FINRA or any other governmental authority, (iv) a material disruption has occurred in commercial banking or securities settlement or clearance services in the United States such that settlement and clearance of the sale of the Securities is impracticable or impossible, or (v) if a banking moratorium has been declared by either federal or New York State authorities.

(b) Liabilities. If this Agreement is terminated pursuant to this Section, such termination shall be without liability of any party to any other party, except as provided in Section 4 hereof, and provided further that this paragraph and Sections 1, 6, 7, 8 and 9(a) shall survive such termination and remain in full force and effect.

SECTION 10. Default by One or More of the Underwriters. If one or more of the Underwriters shall fail at the Closing Time or a Date of Delivery to purchase the Securities which it or they are obligated to purchase under this Agreement (the “Defaulted Securities”), the Representatives shall have the right, within 24 hours thereafter, to make arrangements for one or more of the

non-defaulting Underwriters, or any other underwriters, to purchase all, but not less than all, of the Defaulted Securities in such amounts as may be agreed upon and upon the terms herein set forth; if, however, the Representatives shall not have completed such arrangements within such 24-hour period, then:

(i) if the number of Defaulted Securities does not exceed 10% of the number of Securities to be purchased on such date, each of the non-defaulting Underwriters shall be obligated, severally and not jointly, to purchase the full amount thereof in the proportions that their respective underwriting obligations hereunder bear to the underwriting obligations of all non-defaulting Underwriters, or

(ii) if the number of Defaulted Securities exceeds 10% of the number of Securities to be purchased on such date, this Agreement or, with respect to any Date of Delivery which occurs after the Closing Time, the obligation of the Underwriters to purchase and of the Company to sell the Option Securities to be purchased and sold on such Date of Delivery shall terminate without liability on the part of any non-defaulting Underwriter.

No action taken pursuant to this Section shall relieve any defaulting Underwriter from liability in respect of its default.

In the event of any such default which does not result in a termination of this Agreement or, in the case of a Date of Delivery which is after the Closing Time, which does not result in a termination of the obligation of the Underwriters to purchase and the Company to sell the relevant Option Securities, as the case may be, either (i) the Representatives or (ii) the Company shall have the right to postpone the Closing Time or the relevant Date of Delivery, as the case may be, for a period not exceeding seven days in order to effect any required changes in the Registration Statement or Prospectus or in any other documents or arrangements. As used herein, the term “Underwriter” includes any person substituted for an Underwriter under this Section 10.

SECTION 11. Tax Disclosure. Notwithstanding any other provision of this Agreement, from the commencement of discussions with respect to the transactions contemplated hereby, the Company (and each employee, representatives or other agent of the Company) may disclose to any and all persons, without limitation of any kind, the tax treatment and tax structure (as such terms are used in Sections 6011, 6111 and 6112 of the Code and the Treasury Regulations promulgated thereunder) of the transactions contemplated by this Agreement and all materials of any kind (including opinions or other tax analyses) that are provided to the Company relating to such tax treatment and tax structure.

SECTION 12. Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted by any standard form of telecommunication. Notices to the Underwriters shall be directed to (i) Citigroup Global Markets, Inc., at 388 Greenwich Street, New York, New York 10013, attention of the General Counsel and (ii) Merrill Lynch, Pierce, Fenner & Smith Incorporated, 4 World Financial Center, New York, New York, 10080, attention of the General Counsel, with a copy to (which shall not constitute notice) Hunton & Williams LLP, Riverfront Plaza, East Tower, 951 East Byrd Street, Richmond, Virginia 23219, Attention: Edward W. Elmore, Jr., Esq.; notices to the Company shall be directed to it at 2 Bethesda Metro Center, 14^th Floor, Bethesda, Maryland 20814, attention of the Secretary, with a copy to (which shall not constitute notice) Skadden, Arps, Slate, Meagher & Flom LLP, Four Times Square, New York, New York 10036, Attention: David J. Goldschmidt, Esq.

SECTION 13. No Advisory or Fiduciary Relationship. The Company acknowledges and agrees that (i) the purchase and sale of the Securities pursuant to this Agreement, including the

determination of the offering price of the Securities and any related discounts and commissions, is an arm’s-length commercial transaction between the Company and the Manager, on the one hand, and the several Underwriters, on the other hand, (ii) in connection with the offering contemplated hereby and the process leading to such transaction each Underwriter is and has been acting solely as a principal and is not the agent or fiduciary of the Company or the Manager, or their respective stockholders, creditors, employees or any other party, (iii) no Underwriter has assumed or will assume an advisory or fiduciary responsibility in favor of the Company or the Manager with respect to the offering contemplated hereby or the process leading thereto (irrespective of whether such Underwriter has advised or is currently advising the Company or the Manager on other matters) and no Underwriter has any obligation to the Company or the Manager with respect to the offering contemplated hereby, except the obligations expressly set forth in this Agreement, (iv) the Underwriters and their respective Affiliates may be engaged in a broad range of transactions that involve interests that differ from those of the Company and the Manager, and (v) the Underwriters and their respective agents have not provided any legal, accounting, regulatory or tax advice with respect to the offering contemplated hereby and the Company and the Manager have consulted their own legal, accounting, regulatory and tax advisors to the extent it deemed appropriate.

SECTION 14. Integration. This Agreement supersedes all prior agreements and understandings (whether written or oral) between the Company, the Manager and the Underwriters, or any of them, with respect to the subject matter hereof.

SECTION 15. Parties. This Agreement shall each inure to the benefit of and be binding upon the Underwriters, the Company, the Manager and their respective successors. Nothing expressed or mentioned in this Agreement is intended or shall be construed to give any person, firm or corporation, other than the Underwriters, the Company, the Manager and their respective successors and the controlling persons and officers and directors referred to in Sections 6 and 7 and their heirs and legal representatives, any legal or equitable right, remedy or claim under or in respect of this Agreement or any provision herein contained. This Agreement and all conditions and provisions hereof are intended to be for the sole and exclusive benefit of the Underwriters, the Company, the Manager and their respective successors, and said controlling persons and officers and directors and their heirs and legal representatives, and for the benefit of no other person, firm or corporation. No purchaser of Securities from any Underwriter shall be deemed to be a successor by reason merely of such purchase.

SECTION 16. GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

SECTION 17. TIME. TIME SHALL BE OF THE ESSENCE OF THIS AGREEMENT. EXCEPT AS OTHERWISE SET FORTH HEREIN, SPECIFIED TIMES OF DAY REFER TO NEW YORK CITY TIME.

SECTION 18. Counterparts. This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all such counterparts shall together constitute one and the same Agreement.

SECTION 19. Effect of Headings. The Section headings herein are for convenience only and shall not affect the construction hereof.

If the foregoing is in accordance with your understanding of our agreement, please sign and return to the Company a counterpart hereof, whereupon this instrument, along with all counterparts, will become a binding agreement among the Underwriters, the Company and the Manager in accordance with its terms.


Very truly yours,

AMERICAN CAPITAL AGENCY CORP.

By:
Name:		Samuel A. Flax
Title:		Executive Vice President

AMERICAN CAPITAL AGENCY MANAGEMENT, LLC

By:
Name:		Samuel A. Flax
Title:		Vice President

For themselves and as Representatives of the other Underwriters named in Schedule I hereto.

FORM OF OPINION OF SKADDEN, ARPS, SLATE, MEAGHER & FLOM LLP TO BE DELIVERED PURSUANT TO SECTION 5(b) (CORPORATE OPINION)

The undersigned, an officer and/or director and/or the manager of American Capital Agency Corp., a Delaware corporation (the “Company”), understands that Citigroup Global Markets Inc. and Merrill Lynch, Pierce, Fenner & Smith Incorporated (collectively, in such capacity, the “Representatives”) propose to enter into a Underwriting Agreement (the “Underwriting Agreement”) with the Company and American Capital Agency Management, LLC, a Delaware limited liability company and the manager of the Company (the “Manager”), providing for the public offering of shares of the Company’s common stock, $0.01 par value per share (“Common Stock”). In recognition of the benefit that such an offering will confer upon the undersigned as an officer and/or director or the manager of the Company, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the undersigned agrees with the Representatives that, during a period of 180 days following the date of the Underwriting Agreement, the undersigned will not, without the prior written consent of the Representatives, directly or indirectly, (i) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant for the sale of, or otherwise dispose of or transfer any of the shares of Common Stock or any securities convertible into or exchangeable or exercisable for shares of Common Stock, whether now owned or hereafter acquired by the undersigned or with respect to which the undersigned has or hereafter acquires the power of disposition, file, or cause to be filed, any registration statement under the Securities Act of 1933, as amended, with respect to any of the foregoing (collectively, the “Lock-Up Securities”) or (ii) enter into any swap or any other agreement or any transaction that transfers, in whole or in part, directly or indirectly, the economic consequence of ownership of the Lock-Up Securities, whether any such swap or transaction is to be settled by delivery of shares of Common Stock or other securities, in cash or otherwise.

(1) during the last 17 days of the 180-day lock-up period, the Company issues an earnings release or material news or a material event relating to the Company occurs; or

(2) prior to the expiration of the 180-day lock-up period, the Company announces that it will release earnings results or becomes aware that material news or a material event will occur during the 16-day period beginning on the last day of the 180-day lock-up period.

The restrictions imposed by this lock-up agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event, as applicable, unless the Representatives waive, in writing, such extension.

For the avoidance of doubt, nothing contained herein shall prevent the undersigned from, or restrict the ability of the undersigned to, (i) purchase shares of Common Stock or other securities of the Company or (ii) exercise any options or other convertible securities granted under any benefit plan of the Company; provided, that any shares of Common Stock received upon exercise of such options or other convertible securities shall be subject to the foregoing restrictions.

Notwithstanding the foregoing, the undersigned may make gifts or transfers of Common Stock to, or for the benefit of, family members, charitable institutions, and trusts, limited partnerships or other entities created for estate planning purposes, the principal beneficiaries of which are family members or charitable institutions, subject to the condition that any such family member or charitable institution or other holder shall execute an agreement with the Representatives stating that such transferee is receiving and holding the shares of Common Stock subject to the provisions of this lock-up agreement. In addition, if the undersigned is a corporation, partnership, limited liability company or other entity, the undersigned may transfer shares of Common Stock to persons or other entities that own equity interests in the undersigned, subject to the condition that the recipient shall execute an agreement with the Representatives stating that such recipient is receiving and holding the shares of Common Stock subject to the provisions of this lock-up agreement.

The undersigned also agrees and consents to the entry of stop transfer instructions with the Company’s transfer agent and registrar against the transfer of the Lock-Up Securities except in compliance with the foregoing instructions.

THIS LOCK-UP AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.


Very truly yours,

Signature:


Print Name:

The undersigned, American Capital Strategies, Ltd. (“ACAS”), an affiliate of American Capital Agency Corp., a Delaware corporation (the “Company”), understands that Citigroup Global Markets Inc. and Merrill Lynch, Pierce, Fenner & Smith Incorporated (collectively, in such capacity, the “Representatives”) propose to enter into a Underwriting Agreement (the “Underwriting Agreement”) with the Company and American Capital Agency Management, LLC, a Delaware limited liability company and the manager of the Company (the “Manager”), providing for the public offering of shares of the Company’s common stock, $0.01 par value per share (“Common Stock”). In recognition of the benefit that such an offering will confer upon the undersigned, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the undersigned agrees with the Representatives that, during a period of 365 days following the date of the Underwriting Agreement, the undersigned will not, without the prior written consent of the Representatives, directly or indirectly, (i) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant for the sale of, or otherwise dispose of or transfer any of the 2,500,000 shares of Common Stock acquired by the undersigned pursuant to that certain Stock Purchase Agreement, dated as of the date hereof, between the Company and ACAS (the “Lock-Up Securities”) or (ii) enter into any swap or any other agreement or any transaction that transfers, in whole or in part, directly or indirectly, the economic consequence of ownership of the Lock-Up Securities, whether any such swap or transaction is to be settled by delivery of shares of Common Stock or other securities, in cash or otherwise.

(3) during the last 17 days of the 365-day lock-up period, the Company issues an earnings release or material news or a material event relating to the Company occurs; or

(4) prior to the expiration of the 365-day lock-up period, the Company announces that it will release earnings results or becomes aware that material news or a material event will occur during the 16-day period beginning on the last day of the 365-day lock-up period.

For the avoidance of doubt, nothing contained herein shall prevent the undersigned from, or restrict the ability of the undersigned to purchase shares of Common Stock or other securities of the Company. The undersigned may transfer shares of Common Stock to persons or other entities that own equity interests in the undersigned, subject to the condition that the recipient shall execute an agreement with the Representatives stating that such recipient is receiving and holding the shares of Common Stock subject to the provisions of this lock-up agreement.

THIS LOCK-UP AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.


Very truly yours,

AMERICAN CAPITAL STRATEGIES, LTD.

By:
Name:
Title:


Name of Underwriter		Number of Initial Securities
Citigroup Global Markets Inc.

Merrill Lynch, Pierce, Fenner & Smith Incorporated

Morgan Stanley & Co. Incorporated

Deutsche Bank Securities, Inc.

Credit Suisse Securities (USA) LLC

Banc of America Securities LLC

JMP Securities LLC

HSBC Securities (USA) Inc.

RBC Capital Markets Corporation

Total		12,500,000


CITIGROUP GLOBAL MARKETS INC.

By:
Name:
Title:

MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED

By:
Name:
Title: