NORTHERNSTATES POWER COMPANY (a Minnesotacorporation) UNDERWRITINGAGREEMENT 5.25%First Mortgage Bonds, Series due March 1, 2018

Exhibit 1.01

EXECUTION VERSION

NORTHERN STATES POWER COMPANY

(a Minnesota corporation)

UNDERWRITING AGREEMENT

5.25% First Mortgage Bonds, Series due March 1, 2018

March 11, 2008

Ladies and Gentlemen:

Northern States Power Company, a Minnesota corporation (the “Company”), proposes to sell to the underwriters named in Schedule I hereto (the “Underwriters”), for whom you are acting as representatives (the “Representatives”), an aggregate $500,000,000 principal amount of its First Mortgage Bonds, Series due March 1, 2018 (the “Bonds”) to be issued under its Trust Indenture, dated as of February 1, 1937, from the Company to The Bank of New York Trust Company, N.A., as successor trustee (the “Trustee”), as previously amended, supplemented and restated and as to be amended and supplemented by a supplemental indenture relating to the Bonds (such Trust Indenture as so supplemented, amended and restated being hereinafter referred to as the “Indenture”).

1.     Representations and Warranties by the Company.  The Company represents and warrants to, and agrees with, each Underwriter that:

(a)                                  The Company meets the requirements for use of Form S-3 under the Securities Act of 1933, as amended (the “Act”), and has filed with the Securities and Exchange Commission (the “Commission”) a registration statement on such Form, including a prospectus, for the registration under the Act of the Bonds, which registration statement has become effective.  Such registration statement and prospectus may have been amended or supplemented from time to time prior to the date of this Agreement.  Any such amendment or supplement was filed with the Commission and any such amendment has become effective.  As used in this Agreement:

(i)  “Applicable Time” means 4:45 p.m., New York City time, on the date of this Agreement;

(ii)  “Effective Date” means any date as of which any part of such registration statement relating to the Bonds became, or is deemed to have become, effective under the Act in accordance with the rules and regulations thereunder;

(iii)  “Final Term Sheet” means the final term sheet in the form attached as Schedule III hereto and prepared and filed pursuant to Section 4(a) hereof;

(iv)  “Issuer Free Writing Prospectus” means each “free writing prospectus” (as defined in Rule 405 under the Act), including the Final Term Sheet, prepared by or on behalf of the Company or used or referred to by the Company in connection with the offering of the Bonds;

(v)  “Preliminary Prospectus” means any preliminary form of prospectus supplement relating to the Bonds (together with the base prospectus in the form in which it appears in the Registration Statement) which has heretofore been or is required to be filed by the Company pursuant to Rule 424 under the Act and used prior to the filing of the Prospectus;

(vi)  “Pricing Disclosure Package” means, as of the Applicable Time, the most recent Preliminary Prospectus, together with each Issuer Free Writing Prospectus filed or used by the Company on or before the Applicable Time, including the pricing terms of the offering of the Bonds and the terms and conditions of the Bonds specified in the Final Term Sheet;

(vii)         “Prospectus” means the base prospectus in the form in which it appears in the Registration Statement together with the final prospectus supplement relating to the Bonds, in the form in which it shall be filed by the Company with the Commission pursuant to Rule 424 under the Act (including the base prospectus as so supplemented); and

(viii)        “Registration Statement” means, collectively, the various parts of such registration statement, each as amended as of the Effective Date for such part, including any Preliminary Prospectus or the Prospectus and all exhibits to such registration statement.

Any reference herein to the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 which were filed under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), on or before the date of this Agreement and, if the Company files any document pursuant to the Exchange Act after the date of this Agreement and prior to the termination of the offering of the Bonds by the Underwriters, which documents are deemed to be incorporated by reference into the Prospectus, such filing shall constitute an amendment or supplement to the Prospectus and the term “Prospectus” shall refer also to said prospectus as supplemented by the documents so filed from and after the time said documents are filed with the Commission.  Any reference to the “most recent Preliminary Prospectus” shall be deemed to refer to the latest Preliminary Prospectus included in the Registration Statement or filed pursuant to Rule 424(b) under the Act prior to or on the date hereof (including for purposes hereof, any documents incorporated by reference therein prior to or on the date hereof).

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(b)                                 No order preventing or suspending the use of any Preliminary Prospectus, the Prospectus, the Registration Statement or Issuer Free Writing Prospectus has been issued by the Commission and no proceeding for that purpose has been initiated or threatened by the Commission; the Registration Statement, on the Effective Date, complied in all material respects with the requirements of the Act, the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”), and the respective rules and regulations of the Commission thereunder and did not contain any untrue statement of a material fact or omit any material fact required to be stated therein or necessary in order to make the statements therein not misleading; and, at the time the Prospectus is filed with the Commission and at the Closing Date (as hereinafter defined), the Prospectus will comply in all material respects with the Act and the rules and regulations of the Commission thereunder and will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading;  provided that the Company makes no representations or warranties as to (A) that part of the Registration Statement which shall constitute the Statement of Eligibility (Form T-1) under the Trust Indenture Act of the Trustee or (B) the information contained in or omitted from the Registration Statement or the Prospectus in reliance upon and in conformity with information furnished in writing to the Company by or on behalf of any Underwriter through the Representatives specifically for use in the Registration Statement or Prospectus.  Each Preliminary Prospectus and the prospectus filed as part of the Registration Statement as originally filed or as part of any amendment thereto, or filed pursuant to Rule 424 of the Act, complied when so filed in all material respects with the rules under the Act, 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.

(c)       The documents incorporated by reference in any Preliminary Prospectus or the Prospectus, when they were filed with the Commission, conformed in all material respects to the requirements of the Exchange Act and the rules and regulations of the Commission thereunder, and any documents so filed and incorporated by reference subsequent to the date of this Agreement will, when they are filed with the Commission, conform in all material respects to the requirements of the Exchange Act and the rules and regulations of the Commission thereunder; and none of such documents include or will include any untrue statement of a material fact or omit or will omit to state any material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(d)       The Pricing Disclosure Package, as of the Applicable Time did not, and as of the Closing Date will not, contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading; provided that the Company makes no representations or warranties as to (A) that part of the Registration Statement which shall constitute the Statement of Eligibility (Form T-1) under the Trust Indenture Act of the Trustee or (B) the information contained in or omitted from the Pricing Disclosure Package in reliance upon and in conformity with information furnished in writing to the Company by or on behalf of any Underwriter through the Representatives specifically for use in the Pricing Disclosure Package, which information is specified in Section 10(g) hereof.

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(e)       Prior to the execution of this Agreement, the Company has not made and will not make (other than the Final Term Sheet) any offer relating to the Bonds that would constitute an Issuer Free Writing Prospectus without the prior consent of the Representatives; any such Issuer Free Writing Prospectus the use of which has been consented to by the Company and the Representatives is listed on Schedule II hereto; the Company has complied and will comply with the requirements of Rule 433 under the Act with respect to any such Issuer Free Writing Prospectus; any such Issuer Free Writing Prospectus will not, as of its issue date and through the time the Bonds are delivered pursuant to Section 3 hereof, include any information that conflicts with the information contained in the Registration Statement and the Prospectus; and any such Issuer Free Writing Prospectus, when taken together with the information contained in the Registration Statement, any Preliminary Prospectus and the Prospectus, did not, when issued or filed pursuant to Rule 433, and does not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading.

(f)        Deloitte & Touche LLP, which audited the consolidated financial statements and the related financial statement schedule as of and for the year ended December 31, 2007, incorporated by reference in the Registration Statement, the most recent Preliminary Prospectus and the Prospectus from the Company’s Annual Report on Form 10-K for the year ended December 31, 2007, is an independent registered public accounting firm as required by the Act and the rules and regulations of the Commission thereunder and do not provide to the Company or its subsidiaries any non-audit services which are prohibited by Section 10A(g) of the Exchange Act or which have not been pre-approved in accordance with Section 10A(h) of the Exchange Act.

(g)       The financial statements of the Company and its consolidated subsidiaries filed as a part of or incorporated by reference in the Registration Statement, the most recent Preliminary Prospectus or the Prospectus comply in all material respects with the applicable requirements of the Act and the Exchange Act, as applicable, and fairly present the financial position of the Company and its consolidated subsidiaries as of the dates indicated and the results of their operations and changes in financial position for the periods specified, and have been prepared in conformity with generally accepted accounting principles applied on a consistent basis throughout the periods involved, except as disclosed in such financial statements.

(h)       The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Minnesota with due corporate authority to carry on the business in which it is engaged and to own and operate the properties used by it in such business, as described in the most recent Preliminary Prospectus; the Company is qualified to do business as a foreign corporation and is in good standing under the laws of the States of North Dakota and South Dakota; and the Company is not required by the nature of its business to be licensed or qualified as a foreign corporation in any other state or jurisdiction in which its ownership or lease of property or the conduct of its business requires such qualification and the failure to so qualify might permanently impair title to property material to its operations or its right to enforce a material contract against others or expose it to substantial liabilities; and, except as set forth in the Pricing Disclosure Package and the Prospectus, the Company has all material licenses and approvals required at the date hereof to conduct its business, except where the failure to be so licensed or qualified would not have a material adverse effect on the

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condition (financial or otherwise), earnings, business or properties of the Company and its subsidiaries taken as a whole (a “Material Adverse Effect”).

(i)        The Company has no subsidiaries which would be deemed significant subsidiaries under Regulation S-X.

(j)        The Company has an authorized capitalization as set forth in the Preliminary Prospectus and the Prospectus; except as disclosed in the most recent Preliminary Prospectus and the Prospectus, all the outstanding shares of capital stock or other equity interests of each subsidiary of the Company have been duly and validly authorized and issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, free and clear of any lien, charge, encumbrance, security interest, restriction on voting or transfer or any other claim of any third party.

(k)       Neither the Company nor any of its subsidiaries has sustained since the date of the latest audited financial statements included or incorporated by reference in the most recent Preliminary Prospectus any material loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or action, order or decree of any court, arbitrator or governmental or regulatory authority, otherwise than as set forth or contemplated in the most recent Preliminary Prospectus and the Prospectus; and, since the respective dates as of which information is given in the Registration Statement and the most recent Preliminary Prospectus, neither the Company nor any of its subsidiaries has incurred any liabilities or obligations, direct or contingent, or entered into any transactions, not in the ordinary course of business, which are material to the Company and its subsidiaries taken as a whole, and there has not been any material change in the capital stock or long-term debt of the Company or any of its subsidiaries taken as a whole or any material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, business, financial position, stockholder’s equity, or results of operations of the Company and its subsidiaries taken as a whole, otherwise than as set forth or contemplated in the most recent Preliminary Prospectus and Prospectus.

(l)        Neither the execution and delivery of this Agreement and the Indenture, the issuance and delivery of the Bonds, the consummation of the transactions herein contemplated and the fulfillment of the terms hereof, nor compliance with the terms and provisions of this Agreement, the Bonds and the Indenture will conflict with, or result in the breach of, any of the terms, provisions or conditions of the Articles of Incorporation, as amended, or by-laws of the Company, or conflict with, or result in the breach or violation of any of the terms or provisions of, or constitute a default under or result in the creation or imposition of any lien, charge or encumbrance (other than the lien of the Indenture) upon any property or assets of the Company pursuant to, any indenture, mortgage, deed of trust, loan agreement or other contract, agreement or instrument to which the Company is a party or in which the Company has a beneficial interest or by which the Company is bound or result in the violation of any law, statute, order, rule or regulation applicable to the Company of any court or of any federal or state regulatory body or administrative agency or other governmental body having jurisdiction over the Company or over its properties.

(m)      The Company has full right, power and authority to execute and deliver this Agreement, the Bonds and the Indenture and to perform its obligations hereunder and

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thereunder; and all action required to be taken for the due and proper authorization, execution and delivery of this Agreement, the Bonds and the Indenture and the consummation of the transactions contemplated hereby and thereby has been duly and validly taken.

(n)       The Bonds have been duly authorized for issuance and sale pursuant to this Agreement and, when executed and authenticated in accordance with the Indenture and delivered and paid for as provided herein, will be duly issued and will constitute valid and binding obligations of the Company enforceable in accordance with their terms, except as limited by bankruptcy, insolvency and other laws affecting enforcement of creditors’ rights, and will be entitled to the benefits of the Indenture which will be substantially in the form heretofore delivered to you.

(o)       The Indenture has been duly and validly authorized by the Company and has been duly qualified under the Trust Indenture Act and, when duly executed and delivered by the Company, assuming due authorization, execution and delivery thereof by the Trustee, will constitute a valid and binding obligation of the Company, enforceable in accordance with its terms, except as enforcement thereof may be limited by bankruptcy, insolvency or other laws affecting enforcement of creditors’ rights.

(p)       This Agreement has been duly authorized, executed and delivered by the Company.

(q)       Each of the Indenture and the Bonds conform in all material respects to the descriptions thereof contained in the Pricing Disclosure Package and the Prospectus.

(r)        The statements set forth in the Pricing Disclosure Package and the Prospectus under the captions “Supplemental Description of the First Mortgage Bonds” and “Description of the First Mortgage Bonds,” insofar as they purport to constitute a summary of the terms of the Bonds, are accurate, complete and fair.

(s)       The Minnesota Public Utilities Commission (the “MPUC”) has issued its order approving the Company’s capital structure which order authorizes the issuance of the Bonds and is final and in full force and effect, and no other approval of, or any consent, authorization or order of, or filing or registration with, any regulatory public body, state or federal, or any court having jurisdiction over the Company, is, or will be at the Closing Date (as hereinafter defined), necessary in connection with the issuance and sale of the Bonds pursuant to this Agreement or the execution, delivery and performance of this Agreement and the Indenture, other than such approvals that have been obtained under the Act and the Trust Indenture Act and approvals that may be required under state securities laws.

(t)        The Company has good and valid title to all real and fixed property and leasehold rights described or enumerated in the Indenture (except such properties as have been released from the lien thereof in accordance with the terms thereof) and title to all personal property owned by it, subject only to taxes and assessments not yet delinquent, the lien of the Indenture as to parts of the Company’s property, certain easements, conditions, restrictions, leases, and similar encumbrances which do not affect the Company’s use of such property in the usual course of its business, certain minor defects in titles which are not material, defects in titles to certain properties which are not essential to the Company’s business and mechanics’ lien claims

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being contested or not of record or for the satisfaction or discharge of which adequate provision has been made by the Company; and any real property and buildings held under lease by the Company are held by it under valid, subsisting and enforceable leases with such exceptions as are not material and do not interfere with the use made and proposed to be made of such property and buildings by the Company.

(u)       Other than as set forth or contemplated in the most recent Preliminary Prospectus and the Prospectus, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or any of its subsidiaries is the subject which would reasonably be expected to have a Material Adverse Effect; and, to the best of the Company’s knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others.

(v)       The Company is not and, after giving effect to the offering and sale of the Bonds and the application of the proceeds thereof as described in the most recent Preliminary Prospectus and the Prospectus, will not be an “investment company” or an entity “controlled” by an “investment company,” as such terms are defined in the Investment Company Act of 1940, as amended (the “Investment Company Act”).

(w)      Except as set forth in the most recent Preliminary Prospectus and the Prospectus, the Company and its subsidiaries (i) are in compliance with any and all applicable federal, state and local laws and regulations relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (“Environmental Laws”), (ii) have received all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective business and (iii) are in compliance with all terms and conditions of any such permits, licenses or approvals, except where such noncompliance with Environmental Laws, failure to receive required permits, licenses or other approvals or failure to comply with the terms and conditions of such permits, licenses or approvals would not, individually or in the aggregate, have a Material Adverse Effect.

(x)        Since the date as of which information is given in the most recent Preliminary Prospectus through the Closing Date, and except as may otherwise be disclosed in the most recent Preliminary Prospectus, the Company has not (i) issued or granted any securities or (ii) declared or paid any dividend on its capital stock, and the Company has not (i) incurred any material liability or obligation, direct or contingent, other than liabilities and obligations which were incurred in the ordinary course of business or (ii) entered into any material transaction not in the ordinary course of business.

(y)       Each of the Company and, with respect to clause (ii), its subsidiaries (i) is not in violation of the Company’s Articles of Incorporation, as amended, or by-laws, (ii) is not in default in any material respect, and no event has occurred which, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any material indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which it is a party or by which it is bound or to which any of its properties or assets is subject or (iii) is not in violation of any law, ordinance, governmental rule, regulation or court decree to which the Company or its property or assets may be subject or has failed to obtain any license, permit, certificate, franchise or other governmental

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authorization or permit necessary to the ownership of its property or to the conduct of its business, except, in the case of clauses (ii) and (iii), for defaults, events of default, violations and failures which do not or would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

2.     Purchase and Sale.  Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company agrees to sell to the Representatives and each other Underwriter, and the Representatives and each other Underwriter agree, severally and not jointly, to purchase from the Company, at the purchase price of 99.046% of the principal amount thereof, plus accrued interest, if any, from March 18, 2008 to the Closing Date (as defined below) hereunder, the principal amount of Bonds set forth opposite the name of such Underwriter in Schedule I hereto.

The Company acknowledges and agrees that the Underwriters are acting solely in the capacity of an arm’s length contractual counterparty to the Company with respect to the offering of the Bonds contemplated hereby (including in connection with determining the terms of the offering) and not as a financial advisor or a fiduciary to, or an agent of, the Company or any other person.  Additionally, neither any Representative nor any other Underwriter is advising the Company or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction.  The Company shall consult with its own advisors concerning such matters and shall be responsible for making its own independent investigation and appraisal of the transactions contemplated hereby, and the Underwriters shall have no responsibility or liability to the Company with respect thereto. Any review by the Underwriters of the Company, the transactions contemplated hereby or other matters relating to such transactions will be performed solely for the benefit of the Underwriters and shall not be on behalf of the Company.

3.     Delivery and Payment.  Delivery of and payment for the Bonds shall be made at 9:30 a.m., New York City time, on March 18, 2008, at the offices of Simpson Thacher & Bartlett LLP, 425 Lexington Avenue, New York, New York 10017 (the “Closing Location”), which date and time may be postponed by agreement between the Representatives and the Company (such date and time being herein called the “Closing Date”).  Delivery of the Bonds shall be made to the Representatives for the respective accounts of the several Underwriters against payment by the several Underwriters through the Representatives of the purchase price thereof to or upon the order of the Company in federal (same day) funds to the account specified by the Company to Barclays Capital Inc., by causing The Depository Trust Company (“DTC”) to credit the Bonds to the account of Barclays Capital Inc. at DTC.  The Bonds will be delivered in definitive registered form except that, if for any reason the Company is unable to deliver the Bonds in definitive form, the Company reserves the right, as provided in the Indenture, to make delivery in temporary form.  Any Bonds delivered in temporary form will be exchangeable without charge for Bonds in definitive form.  The Bonds will be registered in the name of Cede & Co., as nominee of DTC and deposited by or on behalf of the Company with DTC or its designated custodian. The Bonds will be made available to the Representatives for checking in New York, New York, not later than 2:00 p.m., New York City time, on the business day preceding the Closing Date.  The documents to be delivered on the Closing Date on behalf of the parties hereto pursuant to Section 7 hereof, including the cross-receipt for the Bonds and any additional documents requested by the Underwriters, will be delivered at the Closing Location, and the Bonds will be delivered at the office of DTC or its designated custodian, all at the Closing Date.  A meeting will be held at

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the Closing Location at 4:00 p.m., New York City time, on the New York Business Day next preceding the Closing Date, at which meeting the final drafts of the documents to be delivered pursuant to the preceding sentence will be available for review by the parties hereto.  For the purposes of this Section 3, “New York Business Day” shall mean each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which banking institutions in New York City are generally authorized or obligated by law or executive order to close.

4.     Agreements of the Company.  The Company agrees with the several Underwriters that:

(a)   The Company will cause the Prospectus, in a form approved by the Representatives, to be filed pursuant to Rule 424(b) under the Act and will notify the Representatives promptly of such filing.  The Company will prepare the Final Term Sheet, containing solely a description of the terms of the Bonds and of the offering, in the form attached as Schedule III hereto, will file such Final Term Sheet pursuant to Rule 433(d) under the Act and will notify the Representatives promptly of such filing.  During the period for which a prospectus relating to the Bonds is required to be delivered under the Act (whether physically or through compliance with Rule 172 under the Act or any similar rule), the Company will promptly advise the Representatives (i) when any amendment to the Registration Statement has been filed or shall have become effective, (ii) when any subsequent supplement to the Prospectus (including documents deemed to be incorporated by reference into the Prospectus) has been filed and shall furnish the Representatives with copies thereof, (iii) of any request by the Commission for any amendment of or supplement to the Registration Statement or the Prospectus or for any additional information, (iv) of the issuance by the Commission of any stop order or of any order preventing or suspending the use of any Preliminary Prospectus, the Prospectus or any Issuer Free Writing Prospectus, (v) of the suspension of the qualification of the Bonds for offering or sale in any jurisdiction, (vi) of the initiation or threatening of any proceeding or examination for any such purpose, and (vii) of any request by the Commission for the amending or supplementing of the Registration Statement, any Preliminary Prospectus, the Prospectus or any Issuer Free Writing Prospectus or for additional information.  During the period for which a prospectus relating to the Bonds is required to be delivered under the Act (whether physically or through compliance with Rule 172 under the Act or any similar rule), the Company will not file (i) any amendment to the Registration Statement or supplement to the Prospectus (excluding documents deemed to be incorporated by reference into the Prospectus) unless the Company has furnished to the Representatives a copy for your review prior to filing and will not file any such proposed amendment or supplement to which the Representatives reasonably object or (ii) any document that would be deemed to be incorporated by reference into the Prospectus without delivering to the Representatives a copy of the document proposed to be so filed, such delivery to be made at least 24 hours prior to such filing, and the Company will consult with the Representatives as to any comments which the Representatives make in a timely manner with respect to such document.  During the period for which a prospectus relating to the Bonds is required to be delivered under the Act (whether physically or through compliance with Rule 172 under the Act or any similar rule), the Company will promptly file all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is required in connection with the offering or sale of the Bonds.  In the event of the issuance of any stop order or of any order preventing or

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suspending the use of any Preliminary Prospectus, the Prospectus or any Issuer Free Writing Prospectus, the Company will promptly use its best efforts to obtain the withdrawal of such order.  In the event of the Company’s receipt of a notice objecting to the use of the form of the Registration Statement or any post-effective amendment thereto, the Company will promptly take such steps including, without limitation, amending the Registration Statement or filing a new registration statement, at its own expense, as may be necessary to permit offers and sales of the Bonds by the Underwriters (and references herein to the “Registration Statement” shall include any such amendment or new registration statement).

(b)   If, at any time when a prospectus relating to the Bonds is required to be delivered under the Act (whether physically or through compliance with Rule 172 under the Act or any similar rule), any event occurs as a result of which the Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, or if it shall be necessary at any time to amend or supplement the Prospectus to comply with the Act or the Exchange Act or the respective rules and regulations of the Commission thereunder, the Company promptly, subject to paragraph (a) of this Section 4, will prepare and file an amendment or supplement to the Prospectus with the Commission and furnish to the Underwriters a reasonable number of copies thereof, or will make a filing with the Commission pursuant to Section 13 or 14 of the Exchange Act, which will correct such statement or omission or will effect such compliance.

(c)   The Company will make generally available to its security holders and to the Representatives a consolidated earnings statement (which need not be audited) of the Company, for a twelve-month period beginning after the date of the Prospectus filed pursuant to Rule 424(b) under the Act, as soon as is reasonably practicable after the end of such period, but in any event no later than eighteen months after the “effective date of the Registration Statement” (as defined in Rule 158(c) under the Act), which will satisfy the provision of Section 11(a) of the Act and the rules and regulations of the Commission thereunder (including at the option of the Company, Rule 158).

(d)   The Company will deliver to the Representatives conformed copies of the Registration Statement, the Preliminary Prospectus, the Prospectus and the Issuer Free Writing Prospectus (including all documents incorporated by reference therein) and, so long as delivery of a prospectus by an Underwriter or dealer may be required by the Act (whether physically or through compliance with Rule 172 under the Act or any similar rule), all amendments of and supplements to such documents, in each case as soon as available and in such quantities as the Representatives may reasonably request.

(e)   Other than the Final Term Sheet prepared and filed pursuant to Section 4(a) hereof, without the prior written consent of the Representatives, the Company has not made and will not make any offer relating to the Bonds that would constitute a “free writing prospectus” as defined in Rule 405 under the Act.

(f)    The Company will promptly file all material required to be filed by the Company with the Commission pursuant to Rule 433(d) under the Act and will retain as and to the extent required by Rule 433 under the Act all Issuer Free Writing Prospectuses not required to be filed

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with the Commission pursuant to the rules and regulations under the Act.  If at any time after the date hereof any events shall have occurred as a result of which any Issuer Free Writing Prospectus, as then amended or supplemented, would conflict with the information in the Registration Statement, the most recent Preliminary Prospectus or the Prospectus or would include an untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in light of the circumstances under which they were made, not misleading, or, if for any other reason it shall be necessary to amend or supplement any Issuer Free Writing Prospectus, the Company will notify the Representatives and, upon their request, file such document and prepare and furnish without charge to each Underwriter as many copies as the Representatives may from time to time reasonably request of an amended or supplemented Issuer Free Writing Prospectus that will correct such conflict, statement or omission or effect such compliance.

(g)   The Company will furnish such information, execute such instruments and take such action as may be required to qualify the Bonds for sale under the laws of such jurisdictions in the United States as the Representatives may designate and will maintain such qualifications in effect so long as required for the distribution of the Bonds; provided that the Company shall not be required to qualify to do business in any jurisdiction where it is not now so qualified or to take any action which would subject it to general or unlimited service of process in any jurisdiction where it is not now so subject.

(h)   So long as the Bonds are outstanding, the Company will furnish (or cause to be furnished) to each of the Representatives, upon request, copies all reports and financial statements filed with the Commission or any national securities exchange.

(i)    During the period beginning from the date of this Agreement and continuing to the Closing Date, the Company will not offer, sell, or otherwise dispose of any long-term debt securities of the Company (except under prior contractual commitments which have been disclosed to you), without the prior written consent of the Representatives, which consent shall not be unreasonably withheld.

(j)    The Company will obtain or make prior to the issuance of the Bonds all regulatory and governmental approvals, consents, authorizations, orders, filings and registrations necessary for the issuance of the Bonds, including, without limitation, any required approvals, consents, authorizations, orders, filings and registrations of the MPUC pertaining to the capital structure of the Company.

(k)   In connection with the offering of the Bonds, until the Underwriters shall have notified the Company and the other Underwriters of the completion of the sale of the Bonds, the Company will not, and will use its best efforts to cause its controlled affiliates not to, either alone or with one or more other persons (i) bid for or purchase for any account in which it or any such affiliate has a beneficial interest any Bonds or attempt to induce any person to purchase any Bonds or (ii) make bids or purchases for the purpose of creating actual, or apparent, active trading in, or of raising the price of, the Bonds.

(l)    The Company will not take, directly or indirectly, any action which is designed to stabilize or manipulate, or which constitutes or which might reasonably be expected to cause or

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result in stabilization or manipulation, of the price of any security of the Company in connection with the offering of the Bonds.

5.     Agreements of the Underwriters.  Each Underwriter hereby represents and agrees that:

(a)   it has not and will not use, authorize use of, refer to, or participate in the planning for use of, any Issuer Free Writing Prospectus or any “free writing prospectus,” as defined in Rule 405 under the Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) required to be filed by the Company with the Commission or retained by the Company pursuant to Rule 433 under the Act, other than (i) a free writing prospectus that contains no “issuer information” (as defined in Rule 433(h)(2) under the Act) that was not included (including through incorporation by reference) in the Preliminary Prospectus or a previously filed Issuer Free Writing Prospectus, (ii) the Final Term Sheet or (iii) any free writing prospectus prepared by such Underwriter and approved by the Company in advance in writing; and

(b)   it will, pursuant to reasonable procedures developed in good faith, retain, as and to the extent required under Rule 433 under the Securities Act, copies of each free writing prospectus used or referred to by it, in accordance with Rule 433.

6.     Expenses.  Whether or not the transactions contemplated hereunder are consummated or this Agreement is terminated, the Company will pay all costs and expenses incident to the performance of the obligations of the Company hereunder, including, without limiting the generality of the foregoing, all costs, taxes and expenses incident to the issue and delivery of the Bonds to the Underwriters, all fees and expenses of the Company’s counsel and accountants, all costs and expenses incident to the preparation, printing, filing and distribution of the Registration Statement (including all exhibits thereto), any Preliminary Prospectus, the Prospectus (including all documents incorporated by reference therein), any Issuer Free Writing Prospectus and any amendments thereof or supplements thereto, all costs and expenses (including fees and expenses of counsel) incurred in connection with “blue sky” qualifications, the determination of the legality of the Bonds for investment by institutional investors and the rating of the Bonds, all costs and expenses of the printing and distribution of all documents in connection with this underwriting, the fees and expenses of the Trustee and any paying agent (including related fees and expenses of any counsel to such parties) and all expenses and application fees incurred in connection with any filing with, and clearance of any offering by, the Financial Industry Regulatory Authority.  Except as provided in this Section 6 and Sections 9 and 10 hereof, the Underwriters will pay all their own costs and expenses, including the fees of their counsel and any advertising expenses in connection with any offer they may make.

7.     Conditions to the Obligations of the Underwriters.  The obligations of the Underwriters to purchase the Bonds shall be subject, in the discretion of the Representatives, to the accuracy of the representations and warranties on the part of the Company contained herein as of the date hereof and the Closing Date, to the accuracy of the statements of the Company’s officers on and as of the Closing Date made in any certificates given pursuant to the provisions

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hereof, to the performance by the Company of its obligations hereunder and to the following additional conditions:

(a)   The Prospectus shall have been filed with the Commission pursuant to Rule 424(b) under the Act within the applicable time period prescribed for such filing by the rules and regulations under the Act and in accordance with Section 4(a) hereof; all filings (including, without limitation, the Final Term Sheet) required by Rule 433 under the Act shall have been made, and no such filings shall have been made without the consent of the Representatives; no stop order suspending the effectiveness of the Registration Statement or any part thereof or preventing or suspending the use of the Prospectus or any Issuer Free Writing Prospectus shall have been issued and no proceeding for that purpose shall have been initiated or threatened by the Commission; and all requests for additional information on the part of the Commission shall have been complied with to the Representatives’ reasonable satisfaction.

(b)   The Representatives shall be furnished with opinions, dated the Closing Date, of Michael C. Connelly, Vice President and General Counsel of the Company, substantially in the form included as Exhibit A, and Jones Day, Chicago, Illinois, counsel for the Company, substantially in the form included as Exhibit B.

(c)   The Representatives shall have received from Simpson Thacher & Bartlett LLP, New York, New York, counsel for the Underwriters, such opinion or opinions dated the Closing Date with respect to such matters as the Representatives may reasonably require, and the Company shall have furnished to such counsel such documents as they reasonably request for the purpose of enabling them to pass upon such matters.

(d)   The Company shall have furnished to the Representatives a certificate of the President or any Vice President of the Company, dated the Closing Date, as to the matters set forth in paragraphs (a) and (h) of this Section 7 and to the further effect that the signers of such certificate have carefully examined the Registration Statement, the Prospectus and this Agreement and that:

(i)            the representations and warranties of the Company in this Agreement are true and correct on and as of the Closing Date with the same effect as if made on the Closing Date, and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied at or prior to the Closing Date; and

(ii)           there has been no material adverse change in the condition of the Company and its subsidiaries taken as a whole, financial or otherwise, or in the earnings, affairs or business prospects of the Company and its subsidiaries taken as a whole, whether or not arising in the ordinary course of business, from that set forth or contemplated by the Registration Statement, the most recent Preliminary Prospectus or Prospectus.

(e)   The Representatives shall have received letters from Deloitte & Touche LLP, independent public accountants for the Company (dated the date of this Agreement and Closing Date, respectively, and in form and substance satisfactory to the Representatives) advising that (i) they are an independent registered public accounting firm with respect to the Company as

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required by the Act and published rules and regulations of the Commission thereunder, (ii) in their opinion, the consolidated financial statements and supplemental schedules included or incorporated by reference in the Registration Statement, Preliminary Prospectus or Prospectus and covered by their opinion filed with the Commission under Section 13 of the Exchange Act comply as to form in all material respects with the applicable accounting requirements of the Exchange Act and the published rules and regulations of the Commission thereunder, (iii) that they have performed limited procedures, not constituting an audit, including a reading of the latest available interim financial statements of the Company, a reading of the minutes of meetings of the Board of Directors, committees thereof, and of the shareholder of the Company since the date of the most recent audited financial statements included or incorporated by reference in the Preliminary Prospectus or Prospectus, inquiries of officials of the Company responsible for financial accounting matters and such other inquiries and procedures as may be specified in such letter, and on the basis of such limited review and procedures nothing came to their attention that caused them to believe that:  (A) any material modifications should be made to any unaudited consolidated financial statements of the Company included or incorporated by reference in the Registration Statement, Preliminary Prospectus or Prospectus for them to be in conformity with generally accepted accounting principles or any unaudited consolidated financial statements of the Company included or incorporated by reference in the Registration Statement, Preliminary Prospectus or Prospectus do not comply as to form in all material respects with the applicable accounting requirements of the Exchange Act and the rules and regulations of the Commission applicable to Form 10-Q; and (B) with respect to the period subsequent to the date of the most recent financial statements included or incorporated by reference in the Prospectus and except as set forth in or contemplated by the Registration Statement, Preliminary Prospectus or Prospectus, there were any changes, at a specified date not more than three business days prior to the date of the letter, in the capital stock of the Company, increases in long-term debt or decreases in stockholder’s equity or net current assets of the Company on a consolidated basis as compared with the amounts shown on the most recent consolidated balance sheet included or incorporated in the Prospectus, or for the period from the date of the most recent financial statements included or incorporated by reference in the Prospectus to such specified date there were any decreases, as compared with the corresponding period in the preceding year, in operating revenues, operating income or net income of the Company and its subsidiaries, except in all instances for changes or decreases set forth in such letter, in which case the letter shall be accompanied by an explanation by the Company as to the significance thereof unless said explanation is not deemed necessary by the Representatives; and (iv) they have carried out specified procedures performed for the purpose of comparing certain specified financial information and percentages (which is limited to financial information derived from general accounting records of the Company or, to the extent not so derived, from schedules prepared by Company officers responsible for such accounting records) included or incorporated by reference in the Registration Statement, Preliminary Prospectus and Prospectus with indicated amounts in the financial statements or accounting records of the Company and (excluding any questions of legal interpretation) have found such information and percentages to be in agreement with the relevant accounting and financial information of the Company referred to in such letter in the description of the procedures performed by them.

(f)    Subsequent to the respective dates as of which information is given in the Registration Statement and the most recent Preliminary Prospectus, there shall not have been any change or decrease specified in the letter or letters referred to in paragraph (e) of this Section 7

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which makes it impractical or inadvisable in the judgment of the Representatives to proceed with the public offering or the delivery of the Bonds on the terms and in the manner contemplated by the Pricing Disclosure Package.

(g)   Subsequent to the execution and delivery of this Agreement, (i) no downgrading shall have occurred in the rating accorded the Bonds or any other debt securities or preferred stock of or guaranteed by the Company by any “nationally recognized statistical rating organization,” as such term is defined by the Commission for purposes of Rule 436(g)(2) under the Act and (ii) no such organization shall have publicly announced that it has under surveillance or review, or has changed its outlook with respect to, its rating of the Bonds or of any other debt securities or preferred stock of or guaranteed by the Company (other than an announcement with positive implications of a possible upgrading).

(h)   Neither the Company nor any of its subsidiaries (i) shall have sustained since the date of the latest audited financial statements included or incorporated by reference in the most recent Preliminary Prospectus any loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or action, order or decree of any court, arbitrator or governmental or regulatory authority, otherwise than as set forth or contemplated in the most recent Preliminary Prospectus, and (ii) shall have incurred since the date of this Agreement, any liabilities or obligations, direct or contingent, or entered into any transactions, not in the ordinary course of business, which are material to the Company and its subsidiaries taken as a whole, and there shall not have been any change in the capital stock or long-term debt of the Company or any of its subsidiaries taken as a whole or any change, or any development involving a prospective change, in or affecting the general affairs, management, business, financial position, stockholder’s equity, results of operations or prospects of the Company and its subsidiaries taken as a whole otherwise than as set forth or contemplated in the most recent Preliminary Prospectus and the Prospectus, the effect of which, in any such case described in clause (i) or (ii) above is in the judgment of the Underwriters so material and adverse as to make it impracticable or inadvisable to proceed with the offering, sale or the delivery of the Bonds on the terms and in the manner contemplated by this Agreement and the Prospectus.

(i)    No Representative shall have advised the Company that the Registration Statement or Prospectus, or any amendment or supplement thereto, contains an untrue statement of fact which in the opinion of counsel for the Underwriters is material or omits to state a fact which in the opinion of counsel for the Underwriters is material and is required to be stated therein or is necessary to make the statements therein not misleading.

(j)    No action shall have been taken and no statute, rule, regulation or order shall have been enacted, adopted or issued by any federal, state or foreign governmental or regulatory authority that would, as of the Closing Date, prevent the issuance or sale of the Bonds; and no injunction or order of any federal, state or foreign court shall have been issued that would, as of the Closing Date, prevent the issuance or sale of the Bonds.

(k)   All corporate proceedings and other legal matters incident to the authorization, form and validity of the Indenture and this Agreement and the transactions contemplated hereby shall be reasonably satisfactory to counsel to the Underwriters, and prior to the Closing Date, the

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Company shall have furnished to the Representatives such further information, certificates and documents as they may reasonably request.

(l)    The Company and Trustee shall have entered into the supplemental Indenture relating to the Bonds, and the Representatives shall have received counterparts, conformed as executed thereof, and the Bonds shall have been duly executed and delivered by the Company and authenticated by the Trustee.

If any of the conditions specified in this Section 7 shall not have been fulfilled when and as required by this Agreement, or if any of the opinions and certificates mentioned above or elsewhere in this Agreement shall not be satisfactory in form and substance to the Representatives and their counsel, this Agreement and all obligations of the Underwriters hereunder may be cancelled at, or at any time prior to, the Closing Date by the Representatives.  Notice of such cancellation shall be given to the Company in writing, or by telephone or telegraph confirmed in writing.

8.     Conditions of Company’s Obligations.  The obligations of the Company to sell and deliver the Bonds are subject to the following conditions:

                                                (a) Prior to the Closing Date, no stop order suspending the effectiveness of the Registration Statement shall have been issued and no proceedings for that purpose shall have been instituted or, to the knowledge of the Company or the Representatives, threatened.

                                                (b) The order of the MPUC referred to in Section 1(s) hereof shall be final and in full force and effect.

If any of the conditions specified in this Section 8 shall not have been fulfilled, this Agreement and all obligations of the Company hereunder may be cancelled on or at any time prior to the Closing Date by the Company.  Notice of such cancellation shall be given to the Underwriters in writing or by telephone or facsimile transmission confirmed in writing.

9.     Reimbursement of Underwriters’ Expenses.  If the sale of the Bonds provided for herein is not consummated (i) because this Agreement is terminated pursuant to Section 12 or (ii) because any condition to the obligations of the Underwriters set forth in Section 7 hereof is not satisfied or because of any refusal, inability or failure on the part of the Company to perform any agreement herein or comply with any provision hereof, other than by reason of a default by any of the Underwriters, the Company will reimburse the Underwriters severally upon demand for all out-of-pocket expenses that shall have been reasonably incurred by them in connection with the proposed purchase and sale of the Bonds, including the reasonable fees and disbursements of counsel for the Underwriters.

10.   Indemnification.

(a)   The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, directors and officers and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Act or Section 20 of the Exchange Act, from and against any and all losses,

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claims, damages and liabilities (including, without limitation, legal fees and other expenses reasonably incurred in connection with any suit, action or proceeding or any claim asserted as such fees and expenses are incurred), joint or several, that arise out of, or are based upon, any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any Preliminary Prospectus, the Prospectus (or any amendment or supplement thereto), or any Issuer Free Writing Prospectus (or amendment or supplement thereto) or any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Act or any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein not misleading, except insofar as such losses, claims, damages or liabilities arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use therein; provided, however, that the foregoing indemnity agreement with respect to any Preliminary Prospectus shall not inure to the benefit of any Underwriter from whom the person asserting any such losses, claims, damages or liabilities purchased Bonds, or any affiliate, director or officer of such Underwriter, or any person controlling such Underwriter where it shall have been determined by a court of competent jurisdiction by final and nonappealable judgment that (i) prior to the Applicable Time the Company shall have notified such Underwriter in writing that a part of the Preliminary Prospectus contains an untrue statement of material fact or omits to state therein a material fact required to be stated therein in order to make the statements therein not misleading (except that such notification shall not be required with respect to the omission of the Rule 430B Information), (ii) such untrue statement or omission of a material fact was corrected in a subsequent Preliminary Prospectus or Prospectus and such subsequent part was provided to such Underwriter far enough in advance of the Applicable Time so that such subsequent part could have been provided to such person prior to the Applicable Time, (iii) the Underwriter did not send or give such subsequent part to such person at or prior to the time of sale of Bonds to such person and (iv) such loss, claim, damage or liability would not have occurred had the Underwriter delivered such subsequent part to such person as provided for in clause (iii) above.

(b)   Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, its officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of Section 15 of the Act or Section 20 of the Exchange Act to the same extent as the indemnity set forth in paragraph (a) above, but only with respect to any losses, claims, damages or liabilities that arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to such Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Preliminary Prospectus or any Issuer Free Writing Prospectus (or any amendment or supplement thereto), it being understood and agreed that the only such information consists of the information identified in Section 10(g) hereof as being provided by the Underwriters.

(c)   If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought or asserted against any person in respect of which indemnification may be sought pursuant to either paragraph (a) or (b) above, such person (the “Indemnified Person”) shall promptly notify the person against whom such indemnification

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may be sought (the “Indemnifying Person”) in writing; provided that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have under this Section 10 except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided, further, that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have to an Indemnified Person otherwise than under this Section 10.  If any such proceeding shall be brought or asserted against an Indemnified Person and it shall have notified the Indemnifying Person thereof, the Indemnifying Person shall retain counsel reasonably satisfactory to the Indemnified Person, which may be counsel to the Indemnifying Person, to represent the Indemnified Person and any others entitled to indemnification pursuant to this Section 10 that the Indemnifying Person may designate in such proceeding and shall pay the reasonable fees and expenses of such counsel related to such proceeding as incurred.  In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary; (ii) the Indemnifying Person has failed within a reasonable time to retain counsel reasonably satisfactory to the Indemnified Person; (iii) the named parties in any such proceeding (including any impleaded parties) include both the Indemnifying Person and the Indemnified Person and the Indemnified Person shall have reasonably concluded that there may be legal defenses available to it that are different from or in addition to those available to the Indemnifying Person; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the Indemnifying Person and the Indemnified Person and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them.  It is understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceeding in the same jurisdiction, be liable for the fees and expenses of more than one separate firm (in addition to any local counsel) for all Indemnified Persons, and that all such fees and expenses shall be reimbursed as they are incurred.  Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing by the Representatives and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and any control persons of the Company shall be designated in writing by the Company.  The Indemnifying Person shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the Indemnifying Person agrees to indemnify each Indemnified Person from and against any loss or liability by reason of such settlement or judgment.  No Indemnifying Person shall, without the written consent of the Indemnified Person, effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of such Indemnified Person, in form and substance reasonably satisfactory to such Indemnified Person, from all liability on claims that are the subject matter of such proceeding and (y) does not include any statement as to or any admission of fault, culpability or a failure to act by or on behalf of any Indemnified Person.