8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of report (Date of earliest event reported): March 25, 2019

ALLIANT ENERGY CORPORATION

(a Wisconsin corporation)

1-9894	4902 N. Biltmore Lane Madison, Wisconsin 53718 Telephone (608) 458-3311	39-1380265
Commission File Number	Name of Registrant, State of Incorporation, Address of Principal Executive Offices and Telephone Number	IRS Employer Identification Number

INTERSTATE POWER AND LIGHT COMPANY

(an Iowa corporation)

1-4117	Alliant Energy Tower Cedar Rapids, Iowa 52401 Telephone (319) 786-4411	42-0331370
Commission File Number	Name of Registrant, State of Incorporation, Address of Principal Executive Offices and Telephone Number	IRS Employer Identification Number

(Former name or former address, if changed since last report.)

This combined Form 8-K is separately filed by Alliant Energy Corporation and Interstate Power and Light Company.

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company  ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 8.01 Other Events.

On March 25, 2019, Interstate Power and Light Company (“IPL”), a subsidiary of Alliant Energy Corporation, entered into an Underwriting Agreement (the “Underwriting Agreement”) with Barclays Capital Inc., J.P. Morgan Securities LLC and Mizuho Securities USA LLC, as representatives of the several underwriters listed therein (the “Underwriters”), pursuant to which IPL agreed to sell, and the Underwriters agreed to purchase, subject to the terms and conditions set forth therein, $300 million aggregate principal amount of IPL’s 3.60% Senior Debentures due 2029 (the “Debentures”), in a public offering (the “Offering”). The Debentures are to be issued under an Indenture dated as of August 20, 2003, between IPL and The Bank of New York Mellon Trust Company, N.A., as successor trustee (the “Indenture”), pursuant to an Officer’s Certificate provided pursuant to the Indenture setting forth the terms of the Debentures (the “Certificate”). The Offering is expected to close, subject to standard closing conditions, on April 1, 2019.

The Debentures are registered under the Securities Act of 1933, as amended, pursuant to an automatic shelf registration statement on Form S-3 (Registration No. 333-222076-02) that IPL filed with the Securities and Exchange Commission (the “SEC”) on December 15, 2017 (the “Registration Statement”). The Registration Statement was supplemented by a Prospectus Supplement setting forth the terms of the Debentures that IPL filed with the SEC on March 26, 2019.

This Current Report on Form 8-K is being filed for the purpose of filing exhibits to the Registration Statement relating to the public offering of the Debentures, and all such exhibits are hereby incorporated into the Registration Statement by reference. The Underwriting Agreement is filed as Exhibit 1.1 and the Certificate is filed as Exhibit 4.1 to this Form 8-K.

On March 25, 2019, IPL issued a press release announcing that it had priced the Offering. The press release is filed as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

Perkins Coie LLP, counsel to IPL, has issued an opinion to IPL, dated April 1, 2019, regarding the legality of the Debentures upon issuance thereof, and Simmons Perrine Moyer Bergman PLC, Iowa counsel to IPL, has issued an opinion to IPL, dated April 1, 2019, regarding certain legal matters relating to Iowa law. The opinions are filed as Exhibit 5.1 and Exhibit 5.2 hereto.

Item 9.01 Financial Statements and Exhibits.

(d)    Exhibits

Exhibit No.	Description
1.1	Underwriting Agreement, dated March 25, 2019, among Interstate Power and Light Company and the underwriters named therein.
4.1	Officer’s Certificate creating the 3.60% Senior Debentures due 2029 of Interstate Power and Light Company.
5.1	Opinion of Perkins Coie LLP, dated April 1, 2019, with respect to the 3.60% Senior Debentures due 2029 of Interstate Power and Light Company.
5.2	Opinion of Simmons Perrine Moyer Bergman PLC, dated April 1, 2019, with respect to the 3.60% Senior Debentures due 2029 of Interstate Power and Light Company.
23.1	Consent of Perkins Coie LLP (contained in Exhibit 5.1 hereto).
23.2	Consent of Simmons Perrine Moyer Bergman PLC (contained in Exhibit 5.2 hereto).
99.1	Press Release of Interstate Power and Light Company, dated March 25, 2019.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, Alliant Energy Corporation and Interstate Power and Light Company have each duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	ALLIANT ENERGY CORPORATION
Date: April 1, 2019	By:	/s/ Robert J. Durian
		Robert J. Durian Senior Vice President and Chief Financial Officer

	INTERSTATE POWER AND LIGHT COMPANY
Date: April 1, 2019	By:	/s/ Robert J. Durian
		Robert J. Durian Senior Vice President and Chief Financial Officer

EX-1.1

Exhibit 1.1

EXECUTION VERSION

INTERSTATE POWER AND LIGHT COMPANY

(an Iowa corporation)

3.60% SENIOR DEBENTURES DUE 2029

UNDERWRITING AGREEMENT

Dated: March 25, 2019

TABLE OF CONTENTS

Page

SECTION 1.	Representations and Warranties		3
(a)	Representations and Warranties by the Company		3
	(i)	Registration Statement, Prospectus and Disclosure at Time of Sale	3
	(ii)	Company is a Well-Known Seasoned Issuer	5
	(iii)	Incorporated Documents	5
	(iv)	Independent Accountants	6
	(v)	Financial Statements	6
	(vi)	No Material Adverse Change in Business	6
	(vii)	Good Standing of the Company	7
	(viii)	No Significant Subsidiaries	7
	(ix)	Capitalization	7
	(x)	Authorization of Agreement	8
	(xi)	Authorization of the Base Indenture	8
	(xii)	Authorization of the Securities	8
	(xiii)	Description of the Securities and the Indenture	8
	(xiv)	Absence of Defaults and Conflicts	8
	(xv)	Absence of Labor Disputes	9
	(xvi)	Absence of Proceedings	9
	(xvii)	Accuracy of Exhibits	10
	(xviii)	Absence of Further Requirements	10
	(xix)	Possession of Licenses and Permits	10
	(xx)	Title to Property	11
	(xxi)	Investment Company Act	11
	(xxii)	Environmental Laws	11
	(xxiii)	Accounting Controls and Disclosure Controls	12
	(xxiv)	Foreign Corrupt Practices Act	13
	(xxv)	Money Laundering Laws	13
	(xxvi)	OFAC	14
	(xxvii)	No Price Stabilization or Manipulation	14
(b)	Officer’s Certificates		14

i

SECTION 2.	Sale and Delivery to Underwriters; Closing	14
(a)	The Securities	14
(b)	Payment	15
(c)	Denominations; Registration	15
SECTION 3.	Covenants of the Company	15
(a)	Compliance with Securities Regulations and Commission Requests	15
(b)	Filing of Amendments	16
(c)	Delivery of Registration Statements	16
(d)	Delivery of Prospectuses	16
(e)	Continued Compliance with Securities Laws	16
(f)	Blue Sky Qualifications	17
(g)	Rule 158	17
(h)	Use of Proceeds	17
(i)	Restriction on Sale of Securities	17
(j)	Reporting Requirements	18
(k)	2005 Act Filings	18
(l)	Rating of Securities	18
(m)	DTC	18
(n)	Compliance with Regulatory Approvals	18
(o)	Issuer Free Writing Prospectus	18
(p)	Final Term Sheet	18
(q)	Notice of Inability to Use Automatic Shelf Registration Statement Form	19
(r)	Filing Fees	19

ii

SECTION 4.	Payment of Expenses	19
(a)	Expenses	19
(b)	Termination of Agreement	19
SECTION 5.	Conditions of Underwriters’ Obligations	20
(a)	Effectiveness of Registration Statement	20
(b)	Opinion of Counsel for Company	20
(c)	Letter from Counsel for Company	20
(d)	Opinion of Counsel for Underwriters	21
(e)	Officers’ Certificate	21
(f)	Accountant’s Comfort Letter	21
(g)	Bring-down Comfort Letter	21
(h)	Maintenance of Rating	22
(i)	Additional Documents	22
(j)	Termination of Agreement	22
SECTION 6.	Indemnification	22
(a)	Indemnification of Underwriters	22
(b)	Indemnification of Company, Directors and Officers	23
(c)	Actions against Parties; Notification	24
(d)	Settlement without Consent if Failure to Reimburse	25
SECTION 7.	Contribution	25

iii

SECTION 8.	Representations, Warranties and Agreements to Survive Delivery	26
SECTION 9.	Termination of Agreement	26
(a)	Termination; General	26
(b)	Liabilities	27
SECTION 10.	Default by One or More of the Underwriters	27
SECTION 11.	Certain Agreements of the Underwriters	28
SECTION 12.	Notices	29
SECTION 13.	Parties	29
SECTION 14.	No Fiduciary Duty	29
SECTION 15.	Governing Law and Time	29
SECTION 16.	Patriot Act	30
SECTION 17.	Effect of Headings	30
SECTION 18.	Counterparts	31

SCHEDULES

Schedule A — List of Underwriters’ Purchase Amounts

Schedule B — Issuer Free Writing Prospectuses contained in the General Disclosure Package

Schedule C — Pricing Information

Schedule D — Final Term Sheet

Schedule E — Underwriter Information

iv

INTERSTATE POWER AND LIGHT COMPANY

(an Iowa corporation)

3.60% SENIOR DEBENTURES DUE 2029

UNDERWRITING AGREEMENT

March 25, 2019

Barclays Capital Inc.

745 7th Avenue

New York, New York 10019

J.P. Morgan Securities LLC

383 Madison Ave

New York, NY 10179

Mizuho Securities USA LLC

320 Park Avenue

New York, NY 10022

As Representatives (as defined below) of the several Underwriters (as defined below)

Ladies and Gentlemen:

Interstate Power and Light Company, an Iowa corporation (the “Company”), confirms its agreement (the “Agreement”) with Barclays Capital Inc. (“Barclays”), J.P. Morgan Securities LLC (“J.P. Morgan”) and Mizuho Securities USA LLC (“Mizuho”), and each of the other underwriters named on Schedule A hereto (collectively, the “Underwriters”, which term shall also include any underwriter substituted as hereinafter provided in Section 10 hereof), for whom Barclays, J.P. Morgan and Mizuho are acting as representatives (in such capacity, the “Representatives”), with respect to the issue and sale by the Company and the purchase by the Underwriters, acting severally and not jointly, of the respective principal amounts set forth on Schedule A of $300,000,000 aggregate principal amount of the Company’s 3.60% Senior Debentures due 2029 (the “Securities”). The Securities will be issued pursuant to an indenture dated as of August 20, 2003 (the “Base Indenture”) between the Company and The Bank of New York Mellon Trust Company, N.A. as successor trustee thereunder (the “Trustee”). The term “Indenture,” as used herein, includes the Base Indenture and the Officer’s Certificate (as defined in the Base Indenture) to be executed in connection with the offering of the Securities, establishing the form and terms of the Securities pursuant to Section 301 of the Base Indenture. The Securities are to be issued in book-entry form and will be registered in the name of Cede & Co. as nominee of The Depository Trust Company (“DTC”) pursuant to the blanket letter agreement, dated October 1, 2003, between the Company and DTC.

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The Company understands 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”) an automatic shelf registration statement on Form S-3 (No. 333-222076-02), including a base prospectus (the “Base Prospectus”), for the registration of certain securities, including the Securities, under the Securities Act of 1933, as amended (the “1933 Act”), and the offering thereof from time to time in accordance with Rule 415 of the rules and regulations of the Commission under the 1933 Act (the “1933 Act Regulations”), which automatic shelf registration statement became effective under the 1933 Act upon filing with the Commission. Promptly after execution and delivery of this Agreement, the Company will prepare and file a prospectus supplement relating to the Securities in accordance with the provisions of Rule 430B (“Rule 430B”) 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 supplement that was omitted from the Registration Statement at the time it first became effective but that is deemed to be a part of and included in such registration statement pursuant to Rule 430B is referred to as “Rule 430B Information.” Such registration statement, at any given time, including the amendments thereto to such time, the exhibits and schedules thereto, at such time, and the Rule 430B Information, is referred to herein as the “Registration Statement.” The final prospectus supplement, together with the Base Prospectus, in the form first furnished to the Representatives by the Company for use in connection with the offering of the Securities, is referred to herein as the “Prospectus.” A “preliminary prospectus” shall be deemed to refer to any preliminary prospectus supplement, together with the Base Prospectus, used in connection with the offering of the Securities that omitted the Rule 430B Information. For the purposes of this Agreement, all references to the “Registration Statement,” the “Prospectus” or any preliminary prospectus shall also be deemed to include all documents incorporated therein by reference pursuant to Item 12 of Form S-3 under the 1933 Act at such time and the documents otherwise deemed to be a part thereof or included therein by the 1933 Act Regulations. For purposes of this Agreement, all references to the Registration Statement, Prospectus or preliminary prospectus or to any amendment or supplement to any of the foregoing shall be deemed to include any 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 are “contained,” “included” or “stated” (or other references of like import) in the Registration Statement, Prospectus or preliminary prospectus shall be deemed to mean and include all such financial statements and schedules and other information which are incorporated by reference in or otherwise deemed by 1933 Act Regulations to be a part of or included in, as of such applicable date, the Registration Statement, Prospectus or preliminary prospectus, as the case may be.

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SECTION 1. Representations and Warranties.

(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)(i) hereof and as of the Closing Time referred to in Section 2(b) hereof, and agrees with each Underwriter, as follows:

(i) Registration Statement, Prospectus and Disclosure at Time of Sale. The Company meets the requirements for use of Form S-3 under the 1933 Act. The Registration Statement is an “automatic shelf registration statement,” as defined in Rule 405 (“Rule 405”) of the 1933 Act Regulations, that automatically became effective not more than three years prior to the date hereof and no stop order suspending the effectiveness of the Registration Statement 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 received from the Commission any notice pursuant to Rule 401(g)(2) (“Rule 401(g)(2)”) of the 1933 Act Regulations objecting to use of the automatic shelf registration statement form and the Company has not otherwise ceased to be eligible to use the automatic shelf registration form.

At the time the Registration Statement became effective (including without limitation any effective dates of any amendments thereto and each deemed effective date with respect to the Underwriters pursuant to Rule 430B(f)(2) of the 1933 Act Regulations) and at the Closing Time, the Registration Statement and any amendments and supplements thereto complied or will comply, as the case may be, in all material respects with the requirements of the 1933 Act and the 1933 Act Regulations and the Trust Indenture Act of 1939, as amended (the “1939 Act”) and the rules and regulations of the Commission under the 1939 Act (the “1939 Act Regulations”), and did not or will not, as the case may be, 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 and the Indenture complied and will comply in all material respects with the requirements of the 1939 Act. 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 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. The representations and warranties in this subsection shall not apply to statements in or omissions from the Registration Statement or Prospectus made in reliance upon and in conformity with information furnished to the Company in writing by any Underwriter through the Representatives expressly for use in the Registration Statement (or any amendment thereto) or Prospectus (or any amendment thereto), it being understood and agreed that the only such information consists of the information contained in Schedule E hereto.

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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 under the 1933 Act, 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), neither (x) the Issuer Free Writing Prospectus(es) (as defined below) listed on Schedule B and the Statutory Prospectus (as defined below), all considered together (collectively, the “General Disclosure Package”), nor (y) any individual Issuer Free Writing Prospectus, when considered together with the General Disclosure Package, will include any untrue statement of a material fact or omit 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.

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.

As used in this subsection and elsewhere in this Agreement:

“Applicable Time” means 4:00 P.M. (Eastern time) on the date of this Agreement.

“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 document incorporated by reference therein and any preliminary or other prospectus supplement deemed to be a part thereof.

“Issuer Free Writing Prospectus” means any “issuer free writing prospectus,” as defined in Rule 433 (“Rule 433”) of the 1933 Act Regulations, relating to the Securities that (i) is required to be filed with the Commission by the Company or (ii) 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) or is exempt from filing pursuant to Rule 433(d)(8)(i) relating to road shows.

4

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 the next sentence, did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained in the Registration Statement or the Prospectus, including any document incorporated by reference therein and any preliminary or other prospectus deemed to be a part thereof that has not been superseded or modified. 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 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, not misleading, the Company has notified or will notify promptly the Representatives so that any use of such Issuer Free Writing Prospectus may cease until it is amended or supplemented. The foregoing two sentences do not apply to statements in or omissions from any Issuer Free Writing Prospectus based upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives expressly for use therein, it being understood and agreed that the only such information consists of the information contained in Schedule E hereto.

(ii) Company is a Well-Known Seasoned Issuer. (A) At the time of filing the Registration Statement, (B) at the time of the most recent amendment thereto for the purposes of complying with Section 10(a)(3) of the 1933 Act (whether such amendment was by post-effective amendment, by incorporated report filed pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended (the “1934 Act”) or by form of prospectus) and (C) as of the date hereof, the Company was and is a “well-known seasoned issuer” as defined in Rule 405.

(iii) Incorporated Documents.

(A)    The documents incorporated or deemed to be incorporated by reference in the Registration Statement, the Statutory Prospectus and the Prospectus, at the time they were or hereafter are filed with the Commission, complied or will comply, as the case may be, in all material respects with the requirements of the 1934 Act and the rules and regulations of the Commission thereunder (the “1934 Act Regulations”), as applicable, and, when read together with the other information in the Registration Statement, the Statutory Prospectus and the Prospectus, did not or will not, as the case may be, 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.

(B)    The description of regulatory matters to which the Company is subject, as disclosed in the Company’s filings with the Commission under the 1934 Act and the 1934 Act Regulations and as incorporated by reference into the Registration Statement, is true and correct in all material respects, except to the extent such description in any specific filing has been superseded, updated or supplemented by such description in a subsequent filing under the 1934 Act or the 1934 Act Regulations made prior to the date hereof or by such description in the Statutory Prospectus and the Prospectus.

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(iv) Independent Accountants. Deloitte & Touche LLP, which has certified certain financial statements of the Company and its consolidated subsidiaries and delivered its report with respect to the audited financial statements of the Company and related schedule included in the Registration Statement, the Statutory Prospectus and the Prospectus, is an independent registered public accounting firm with respect to the Company and its subsidiaries as required by the 1933 Act and the rules of the Public Company Accounting Oversight Board.

(v) Financial Statements. The financial statements included in the Registration Statement, the Statutory Prospectus and the Prospectus, together with the related schedules and notes, present fairly in all material respects the financial position of the Company and its consolidated subsidiaries at the dates indicated and the statements of income, changes in common equity and cash flows of the Company and its consolidated subsidiaries for the periods specified; said financial statements have been prepared in conformity with generally accepted accounting principles (“GAAP”) applied on a consistent basis throughout the periods involved. The supporting schedules included in the Registration Statement, if any, present fairly in all material respects in accordance with GAAP the information required to be stated therein. The selected financial data and the summary financial information included in the Statutory Prospectus and the Prospectus present fairly in all material respects the information shown therein and have been compiled on a basis consistent with that of the audited financial statements included in the Registration Statement. The interactive data in eXtensible Business Reporting Language (“XBRL”) incorporated by reference into the Registration Statement, the Statutory Prospectus and the Prospectus present fairly in all material respects the information called for and was prepared in accordance with the Commission’s rules and guidelines applicable thereto.

(vi) No Material Adverse Change in Business. Since the respective dates as of which information is given in the Registration Statement, the General Disclosure Package and the Prospectus, except as otherwise stated therein, (A) there has been no material adverse change in the condition, financial or otherwise, earnings or business affairs of the Company and its subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business nor have there been any developments involving a prospective material adverse change of the Company and its 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, and (C) except for regular dividends on the common stock, $2.50 par value per share, of the Company and the 5.100% Series D Cumulative Perpetual Preferred Stock, $.01 par value per share, of the Company, there has been no dividend or distribution of any kind declared, paid or made by the Company on any class of its capital stock.

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(vii) Good Standing of the Company. The Company has been duly organized and is validly existing as a corporation under the laws of the State of Iowa and has corporate power and authority to own, lease and operate its properties and to conduct its business as described in the General Disclosure Package and the Prospectus and to enter into and perform its obligations under this Agreement; and 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 so to qualify or to be in good standing would not result in a Material Adverse Effect.

(viii) No Significant Subsidiaries. The Company has no “significant subsidiary” as defined in Rule 1-02(w) of Regulation S-X.

(ix) Capitalization. The issued and outstanding capital stock of the Company as of the date hereof is 13,370,788 shares of common stock and 8,000,000 shares of the Company’s 5.100% Series D Cumulative Perpetual Preferred Stock (except for subsequent issuances, if any, pursuant to this Agreement, pursuant to existing reservations, agreements or employee benefit plans, or pursuant to the exercise of convertible securities or options outstanding on the date hereof or pursuant to any dividend reinvestment plan). All of 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 and none of the outstanding shares of capital stock of the Company was issued in violation of the preemptive or other similar rights of any securityholder of the Company. As of the date hereof, except for 8,000,000 shares of the Company’s 5.100% Series D Cumulative Perpetual Preferred Stock, all of the issued and outstanding shares of the capital stock of the Company are owned by Alliant Energy Corporation, a Wisconsin corporation (the “Parent”), free and clear of all liens, encumbrances, equities or claims. Immediately prior to the Closing Time, except for 8,000,000 shares of the Company’s 5.100% Series D Cumulative Perpetual Preferred Stock, all of the issued and outstanding shares of capital stock of the Company will be owned directly by the Parent, free and clear of all liens, encumbrances, equities or claims. The Parent is a “holding company” as defined under the Public Utility Holding Company Act of 2005 (the “2005 Act”). The Company is a “subsidiary company” within the Alliant Energy Corporation “holding company system,” each as defined under the 2005 Act.

7

(x) Authorization of Agreement. The Company has all requisite corporate power and authority to execute and deliver this Agreement and to perform its obligations hereunder. This Agreement has been duly authorized, executed and delivered by the Company.

(xi) Authorization of the Base Indenture. The Base Indenture has been duly authorized, executed and delivered by the Company and duly qualified under the 1939 Act and constitutes a valid and binding agreement of the Company enforceable against the Company in accordance with its terms, except (A) as enforcement thereof may be limited by bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium or similar laws affecting the enforcement of creditors’ rights generally and (B) as enforcement thereof is subject to general principles of equity (regardless of whether enforcement is considered in a proceeding in equity or at law).

(xii) Authorization of the Securities. The Securities have been duly authorized and, at the Closing Time, will have been duly executed by the Company and, when authenticated, issued and delivered in the manner provided for in the Indenture and delivered against payment of the purchase price therefor as provided for in this Agreement, will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their terms, except as the enforcement thereof may be limited by bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium or similar laws affecting enforcement of creditors’ rights generally and except as enforcement thereof is subject to general principles of equity (regardless of whether enforcement is considered in a proceeding in equity or at law) and will be in the form contemplated by, and entitled to the benefits of, the Indenture.

(xiii) Description of the Securities and the Indenture. The statements relating to the Securities and the Indenture contained in the Prospectus and the General Disclosure Package conform, respectively, in all material respects to the terms of the Securities and the Indenture.

(xiv) Absence of Defaults and Conflicts. Neither the Company nor any of its subsidiaries is (A) in violation of its articles of incorporation or bylaws, each as amended or (B) 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 Company or any of its subsidiaries is a party or by which it or any of them may be bound, or to which any of the property or assets of the Company or any of its subsidiaries is subject (collectively, “Agreements and Instruments”), except for any such defaults with respect to this clause (B) that would not result in a Material Adverse Effect; and the execution, delivery and performance of this Agreement, the Indenture and the Securities, the consummation of the transactions contemplated herein and in the

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Registration Statement (including the issuance and sale of the Securities and the use of the proceeds from the sale of the Securities as described in the General Disclosure Package and the Prospectus under the caption “Use of Proceeds”), and compliance by the Company with its obligations hereunder and under the Indenture and the Securities 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 or a Repayment Event (as defined below) under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to, the Agreements and Instruments except for such conflicts, breaches or defaults or liens, charges or encumbrances that, singly or in the aggregate, would not result in a Material Adverse Effect, nor will such action result in any violation of the provisions of (I) the articles of incorporation or bylaws, each as amended, of the Company or any of its subsidiaries or (II) 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 of its subsidiaries or any of their assets, properties or operations, except for any such violations with respect to this clause (II) as would not, individually or in the aggregate, result in a Material Adverse Effect. As used herein, a “Repayment Event” means any event or condition which gives the holder of any note, debenture or other evidence of indebtedness (or any person acting on such holder’s behalf) the right to require the repurchase, redemption or repayment of all or a portion of such indebtedness by the Company or any of its subsidiaries.

(xv) Absence of Labor Disputes. No labor dispute with the employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is imminent, which would reasonably be expected to result in a Material Adverse Effect.

(xvi) Absence of Proceedings. Except as disclosed in the General Disclosure Package and the Prospectus, 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 of its subsidiaries which would reasonably be expected to result in a Material Adverse Effect, or which would reasonably be expected to materially and adversely affect (A) the properties or assets of the Company and its subsidiaries or (B) the consummation of the transactions contemplated by 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 of its subsidiaries is a party or of which any of their respective property or assets is the subject which are not described in the General Disclosure Package and the Prospectus,

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including ordinary routine litigation incidental to the business of the Company and its subsidiaries, would not reasonably be expected to result in a Material Adverse Effect. 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.

(xvii) Accuracy of Exhibits. There are no contracts or documents which are required to be described in the Registration Statement, the General Disclosure Package, the Prospectus or the documents incorporated by reference therein or to be filed as exhibits thereto which have not been so described and filed as required except that this Agreement, an opinion of Perkins Coie LLP with respect to the validity of the Securities and the Officer’s Certificate establishing the form and the terms of the Securities will be filed as exhibits to a Current Report on Form 8-K which shall be filed with the Commission in accordance with the 1934 Act and the 1934 Act Regulations.

(xviii) 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 or for the due execution, delivery and performance of the Indenture by the Company, except (A) such as have been already obtained, (B) such as may be required under the 1933 Act or the 1933 Act Regulations or state securities laws, and (C) such as may be required by the 2005 Act, solely with respect to the filing of a Report of Securities Issued required to be made with the Federal Energy Regulatory Commission subsequent to the Closing Time (such 2005 Act filings to be made by the Company).

(xix) Possession of Licenses and Permits. Except as described in the General Disclosure Package and the Prospectus, (A) the Company and its subsidiaries possess such permits, licenses, approvals, consents and other authorizations (collectively, “Governmental Licenses”) issued by the appropriate federal, state, local or foreign regulatory agencies or bodies necessary to conduct the business now operated by them in the manner described in the Prospectus except where the failure to possess any such Governmental Licenses would not have a Material Adverse Effect, (B) the Company and its subsidiaries are in compliance with the terms and conditions of all such Governmental Licenses, except where the failure so to possess or comply would not, singly or in the aggregate, have a Material Adverse Effect, (C) all of the Governmental Licenses are valid and in full force and effect, except where the invalidity of such Governmental Licenses or the failure of such Governmental Licenses to be

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in full force and effect would not have a Material Adverse Effect and (D) neither the Company nor any of its subsidiaries has received any notice of proceedings relating to the revocation or modification of any such Governmental Licenses which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would result in a Material Adverse Effect. Without limiting the foregoing, the Company has received an authorization letter from the Federal Energy Regulatory Commission (the “FERC Authorization”), dated November 14, 2017, authorizing the issuance of the Securities and such issuance is in compliance with the terms and conditions of such authorization. Such authorization is in full force and effect and has not been amended, supplemented or otherwise modified. No proceeding to review, suspend, limit, modify, restrict or revoke such authorization has been instituted.

(xx) Title to Property. The Company and its subsidiaries have good and marketable title to all real property owned by the Company and its subsidiaries and good title to all other properties owned by them, in each case, free and clear of all mortgages, pledges, liens, security interests, claims, restrictions or encumbrances of any kind except such as (A) are described in the General Disclosure Package and the Prospectus or (B) do not, singly or in the aggregate, materially affect the value of such property and do not interfere with the use made and proposed to be made of such property by the Company or any of its subsidiaries; and all of the leases and subleases material to the business of the Company and its subsidiaries, considered as one enterprise, and under which the Company or any of its subsidiaries holds properties described in the General Disclosure Package and the Prospectus, are in full force and effect, and neither the Company nor any of its subsidiaries has any notice of any material claim of any sort that has been asserted by anyone adverse to the rights of the Company or any of its subsidiaries under any of the leases or subleases mentioned above, or affecting or questioning the rights of the Company or any of its subsidiaries to the continued possession of the leased or subleased premises under any such lease or sublease, except where such would not have a Material Adverse Effect.

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

(xxii) Environmental Laws. Except as described in the General Disclosure Package and except as would not, singly or in the aggregate, result in a Material Adverse Effect, (A) neither the Company nor any of its subsidiaries is in violation of any federal, state, local or foreign statute, law, rule, regulation, ordinance, code, policy or rule of common law or any judicial or administrative interpretation thereof, including any judicial

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or administrative order, consent, decree or judgment, relating to pollution or protection of human health, the environment (including, without limitation, ambient air, surface water, groundwater, land surface or subsurface strata) or wildlife, including, without limitation, laws and regulations relating to the release or threatened release of chemicals, pollutants, contaminants, wastes, toxic substances, hazardous substances, petroleum or petroleum products (collectively, “Hazardous Materials”) or to the manufacture, processing, distribution, use, treatment, storage, disposal, transport or handling of Hazardous Materials (collectively, “Environmental Laws”), (B) the Company and its subsidiaries have all permits, authorizations and approvals required under any applicable Environmental Laws and are each in compliance with their requirements, (C) there are no pending or, to the knowledge of the Company, threatened administrative, regulatory or judicial actions, suits, demands, demand letters, claims, liens, notices of noncompliance or violation, investigations or proceedings relating to any Environmental Laws against the Company or any of its subsidiaries and (D) there are no events or circumstances that might reasonably be expected to form the basis of an order for clean-up or remediation, or an action, suit or proceeding by any private party or governmental body or agency, against or affecting the Company or any of its subsidiaries relating to Hazardous Materials or any Environmental Laws.

(xxiii) Accounting Controls and Disclosure Controls. The Company together with its consolidated subsidiaries maintains 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) access to assets is permitted only in accordance with management’s general or specific authorization, (D) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences and (E) interactive data in XBRL included or incorporated by reference in the Registration Statement, the Statutory Prospectus and the Prospectus is prepared in accordance with the Commission’s rules and guidelines applicable thereto. Except as described in the General Disclosure Package and the Prospectus, since the end of the Company’s most recent audited fiscal year, there has been (I) no material weakness in the Company’s internal control over financial reporting (whether or not remediated) and (II) 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 together with its consolidated subsidiaries employs 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.

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(xxiv) Cybersecurity.. The Company and its subsidiaries’ information technology assets and equipment, computers, systems, networks, hardware, software, websites, applications, and databases (collectively, “IT Systems”) are adequate for, and operate and perform in all material respects as required in connection with the operation of the business of the Company and its subsidiaries as currently conducted, free and clear of all material bugs, errors, defects, Trojan horses, time bombs, malware and other corruptants. The Company and its subsidiaries have implemented and maintained commercially reasonable controls, policies, procedures, and safeguards to maintain and protect their material confidential information and the integrity, continuous operation, redundancy and security of all IT Systems and data (including all personal, personally identifiable, sensitive, confidential or regulated data (“Personal Data”)) used in connection with their businesses, and there have been no breaches, violations, outages or unauthorized uses of or accesses to same, except for those that have been remedied without material cost or liability or the duty to notify any other person, nor any incidents under internal review or investigations relating to the same. The Company and its subsidiaries are presently in material compliance with all applicable laws or statutes and all judgments, orders, rules and regulations of any court or arbitrator or governmental or regulatory authority, internal policies and contractual obligations relating to the privacy and security of IT Systems and Personal Data and to the protection of such IT Systems and Personal Data from unauthorized use, access, misappropriation or modification.

(xxv) 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 could result in a violation or a sanction for violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, or the rules or regulations thereunder; and the Company and its subsidiaries have instituted and maintain policies and procedures to ensure compliance therewith. 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 will use any part of the proceeds of the offering, directly or indirectly, in violation of the Foreign Corrupt Practices Act of 1977, as amended, or the rules or regulations thereunder.

(xxvi) 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, including any money laundering statutes and 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 is pending or, to the best knowledge of the Company, threatened against the Company or any of its subsidiaries with respect to the Money Laundering Laws.

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(xxvii) OFAC. 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 (i) is, or is controlled or 50% or more owned by or is acting on behalf of, an individual or entity that is currently the subject of any sanctions administered or enforced by the United States (including any administered or enforced by the Office of Foreign Assets Control of the U.S. Department of the Treasury, the U.S. Department of State or the Bureau of Industry and Security of the U.S. Department of Commerce), the United Nations Security Council, the European Union, the United Kingdom (including sanctions administered or enforced by Her Majesty’s Treasury) or other relevant sanctions authority (collectively, “Sanctions”), (ii) is located, organized or resident in a country or territory that is, or whose government is, the subject of Sanctions that broadly prohibit dealings with that country or territory (the “Sanctioned Countries”) or (iii) will, directly or indirectly, use the proceeds of this offering, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other individual or entity in any manner that would result in a violation of any Sanctions by, or could result in the imposition of Sanctions against, any individual or entity (including any individual or entity participating in the offering, whether as underwriter, advisor, investor or otherwise). The Company and its subsidiaries (as of the date hereof) have not knowingly engaged in, are not now knowingly engaged in and will not knowingly engage in any dealings or transactions with any person that at the time of the dealing or transaction is or was the subject or the target of Sanctions or with any of the Sanctioned Countries, in each case if such dealing or transaction is prohibited by law.

(xxviii) No Price Stabilization or Manipulation. The Company has not taken, directly or indirectly, any action designed to or that could reasonably be expected to cause or result in any stabilization or manipulation of the price of the Securities.

(b)    Officer’s Certificates. Any certificate signed by any officer of the Company or any of its subsidiaries delivered to the Representatives or to counsel for the Underwriters shall be deemed a representation and warranty by the Company to each Underwriter as to the matters covered thereby.

SECTION 2. Sale and Delivery to Underwriters; Closing.

(a) The Securities. On the basis of the representations, warranties and agreements 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 set forth in Schedule C, the aggregate principal amount of Securities set forth in Schedule A opposite the name of such Underwriter, plus any additional principal amount of Securities which such Underwriter may become obligated to purchase pursuant to the provisions of Section 10 hereof.

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(b) Payment. Payment of the purchase price for, and delivery of certificates for, the Securities shall be made at the offices of the Company at 4902 North Biltmore Lane, Madison, Wisconsin 53718, or at such other place as shall be agreed upon by the Representatives and the Company, at 10:00 A.M. (Eastern time) on the fifth business day after the date hereof (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”).

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 Securities that it has agreed to purchase.

(c) Denominations; Registration. Certificates for the Securities shall be in such denominations (in integral multiples of $1,000) as the Representatives may request in writing at least two full business days before the Closing Time and registered in the name of Cede & Co., as nominee of DTC. The certificates for the Securities will be made available for examination and packaging by the Representatives in New York, New York not later than noon (Eastern time) on the last business day prior to the Closing Time.

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), will notify the Representatives immediately 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 with respect to the Registration Statement, (iii) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus 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)), 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.

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(b) Filing of Amendments. The Company will give the Representatives notice of its intention to file or prepare any amendment, supplement or revision to the Registration Statement, preliminary prospectus or Prospectus if such amendment, supplement or revision relates to either any preliminary prospectus in connection with the offering of the Securities (including any prospectus included in the Registration Statement at the time it became effective) or to the Prospectus, whether pursuant to the 1933 Act, the 1934 Act or otherwise and 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.

(c) Delivery of Registration Statements. The Company has furnished or will deliver to the Representatives and counsel for the Underwriters, without charge, copies of the Registration Statement and of each amendment thereto (including exhibits filed therewith or incorporated by reference therein and documents incorporated or deemed to be incorporated by reference therein) and copies of all consents and certificates of experts, and will also deliver to the Representatives, without charge, a conformed copy of the Registration Statement 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 or will deliver to each Underwriter, without charge, as many copies of the final 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 or the 1934 Act (the “Prospectus Delivery Period”), 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 and the 1939 Act and the 1939 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 reasonable opinion of counsel for the Underwriters or for the Company, to amend the Registration Statement or amend

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or supplement the Prospectus in order that the Registration Statement or 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 reasonable 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), 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, and the Company will furnish to the Underwriters such number of copies of such amendment or supplement as the Underwriters may reasonably request.

(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 so long as required for the sale of the Securities; 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. In each jurisdiction in which the Securities have been so qualified, the Company will file such statements and reports as may be required by the laws of such jurisdiction to continue such qualification in effect for such period.

(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 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 General Disclosure Package and the Prospectus under “Use of Proceeds.”

(i) Restriction on Sale of Securities. From the date of the Prospectus until the Closing Time, 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 debt securities of the Company or any securities convertible into or exercisable or exchangeable for debt securities of the Company 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 debt securities of the Company, whether any such swap or transaction described in clause (i) or (ii) above is to be settled by delivery of debt securities of the Company or such other securities, in cash or otherwise. The foregoing sentence shall not apply to the Securities to be sold hereunder.

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(j) Reporting Requirements. The Company, during the period when the Prospectus is required to be delivered under the 1933 Act or the 1934 Act, will file all documents required to be filed with the Commission pursuant to the 1934 Act within the time periods required by the 1934 Act and the 1934 Act Regulations.

(k) 2005 Act Filings. The Company shall timely file all notifications, forms and reports that may be required under the 2005 Act so as to permit the completion of the distribution and sale of the Securities as contemplated in this Agreement and in the Prospectus.

(l) Rating of Securities. The Company shall take all reasonable action necessary to enable Standard & Poor’s Ratings Services, a division of McGraw Hill, Inc. (“S&P”), and Moody’s Investors Service Inc. (“Moody’s”) to provide their respective credit ratings of the Securities.

(m) DTC. The Company will cooperate with the Representatives and use its best efforts to permit the Securities to be eligible for clearance and settlement through the facilities of DTC.

(n) Compliance with Regulatory Approvals. The Company will comply with the terms and conditions of the final order of the FERC Authorization, as such authorization is amended from time to time until superseded, and shall timely file all notifications, forms and reports that may be required in connection therewith so as to permit the completion of the distribution and sale of the Securities as contemplated in this Agreement and in the Prospectus.

(o) Issuer Free Writing Prospectus. The Company 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 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. Any such free writing prospectus consented to by the Company and the Representatives is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company 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.

(p) Final Term Sheet. The Company will prepare a final term sheet containing only a description of the Securities, in a form attached hereto as Schedule D and approved by the Representatives, and will file such term sheet pursuant to Rule 433(d) of the 1933 Act Regulations within the time required by such rule (such term sheet, the “Final Term Sheet”). The Final Term Sheet is an Issuer Free Writing Prospectus for purposes of this Agreement.

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(q) Notice of Inability to Use Automatic Shelf Registration Statement Form. If, at any time during the Prospectus Delivery Period, the Company receives from the Commission a notice pursuant to Rule 401(g)(2) or otherwise ceases to be eligible to use the automatic shelf registration statement form, the Company will (i) promptly notify the Representatives, (ii) promptly file a new registration statement or post-effective amendment on the proper form relating to the Securities, in a form satisfactory to the Representatives, (iii) use its best efforts to cause such registration statement or post-effective amendment to be declared effective and (iv) promptly notify the Representatives of such effectiveness. The Company will take all other action necessary or appropriate to permit the public offering and sale of the Securities to continue as contemplated in the registration statement that was the subject of the Rule 401(g)(2) notice or for which the Company has otherwise become ineligible. References herein to the Registration Statement shall include such new registration statement or post-effective amendment, as the case may be.

(r) Filing Fees. The Company agrees to pay the required Commission filing fees relating to the Securities within the time required by and in accordance with Rules 456(b)(1) and 457(r) of the 1933 Act Regulations.

SECTION 4. Payment of Expenses.

(a) Expenses. The Company will pay 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 any schedules or exhibits and any document incorporated therein by reference) and of each amendment or supplement thereto, (ii) the reproduction and delivery to the Underwriters of this Agreement, the Indenture, any Agreement among the 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 transfer taxes and any stamp or other duties payable upon the sale, issuance or delivery of the Securities to the Underwriters and any charges of DTC in connection therewith, (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 the Blue Sky Survey and any supplement thereto (provided that counsel fees in connection therewith do not exceed $5,000), (vi) the printing and delivery to the Underwriters of copies of each Issuer Free Writing Prospectus, each preliminary prospectus and the Prospectus and any amendments or supplements thereto, (vii) the fees and expenses of the Trustee, including the fees and disbursements of counsel for the Trustee in connection with the Indenture and the Securities and (viii) any fees payable in connection with the rating of the Securities.

(b) Termination of Agreement. If this Agreement is terminated by the Representatives in accordance with the provisions of Section 5 or clause (i) or (iii) of Section 9(a) hereof, the Company shall reimburse the Underwriters for all of their out-of-pocket expenses, including the reasonable fees and disbursements of counsel for the Underwriters (provided that such out-of-pocket expenses, fees and disbursements do not exceed $200,000).

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

(a) Effectiveness of Registration Statement. The Registration Statement has become effective under the 1933 Act upon filing with the Commission 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 430B Information shall have been filed with the Commission in accordance with Rule 424(b) without reliance on Rule 424(b)(8).

(b) Opinion of Counsel for Company. At the Closing Time, the Representatives shall have received the opinion, dated as of the Closing Time, of (i) Perkins Coie LLP, counsel for the Company, in form and substance reasonably satisfactory to counsel for the Underwriters, together with signed or reproduced copies of such letter for each of the other Underwriters, in the form previously agreed to by the parties and (ii) Simmons Perrine Moyer Bergman PLC, local counsel for the Company, in form and substance reasonably satisfactory to counsel for the Underwriters, together with signed or reproduced copies of such letter each of the other Underwriters, in the form previously agreed to by the parties. At the Closing Time, the Representatives shall have received the opinion regarding certain state and local regulatory matters, dated as of the Closing Time, of Jake Blavat, Lead Attorney of the Company, in form and substance reasonably satisfactory to counsel for the Underwriters, together with signed or reproduced copies of such letter for each of the other Underwriters, in the form previously agreed to by the parties. In rendering such opinions, each such counsel may rely as to matters of fact (but not as to legal conclusions), to the extent they deem proper, on certificates of responsible officers of the Company and its subsidiaries and of public officials.

(c) Letter from Counsel for Company. At the Closing Time, the Representatives shall have received a disclosure letter, dated as of the Closing Time, in form and substance reasonably satisfactory to counsel for the Underwriters, together with signed or reproduced copies of such letter for each of the other Underwriters, of Perkins Coie LLP, counsel for the Company, in the form previously agreed to by the parties.

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(d) Opinion of Counsel for Underwriters. At the Closing Time, the Representatives shall have received the opinion, dated as of the Closing Time, of Gibson, Dunn & Crutcher LLP, counsel for the Underwriters, together with signed or reproduced copies of such letter for each of the other Underwriters. In giving such opinion such counsel may rely, as to all matters governed by the laws of jurisdictions other than the law of the State of New York, the federal law of the United States and the General Corporation Law of the State of Delaware, upon the opinions of counsel satisfactory to the Representatives. In rendering such opinion, such counsel may rely as to matters of fact (but not as to legal conclusions), to the extent they deem proper, on certificates of responsible officers of the Company and its subsidiaries and of public officials.

(e) 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 General Disclosure Package, any material adverse change in the condition, financial or otherwise, in the earnings or business affairs of the Company and its subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business, nor shall there have been any developments involving a prospective material adverse change 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 or a Vice President of the Company and of the chief financial or chief accounting officer of the Company, dated as of the Closing Time, together with signed or reproduced copies of such letter for each of the other Underwriters, to the effect that (i) there has been no such material adverse change or any developments involving a prospective 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 in all material respects with all agreements and satisfied all conditions on its part to be performed or satisfied at or prior to the Closing Time, (iv) the Company is not in default in the performance of any of the covenants to be performed by it under the Indenture and (v) 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 the knowledge of the Company, are contemplated by the Commission.

(f) Accountant’s Comfort Letter. At the time of the execution of this Agreement, the Representatives shall have received from Deloitte & Touche LLP a letter dated such date, in form and substance satisfactory to the Representatives, together with signed or reproduced copies of such letter 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 General Disclosure Package and the Prospectus.

(g) Bring-down Comfort Letter. At the Closing Time, the Representatives shall have received from Deloitte & Touche LLP a letter, dated as of the Closing Time, together with signed or reproduced copies of such letter for each of the other Underwriters, to the effect that they reaffirm the statements made in the letter furnished pursuant to subsection (f) of this Section 5, except that the specified date referred to shall be a date not more than three business days prior to the Closing Time.

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(h) Maintenance of Rating. At the Closing Time, the Securities shall be rated at least “Baal” by Moody’s and “A-” by S&P, and the Company shall have delivered to the Representatives a letter dated the Closing Time, from each such rating agency, or other evidence satisfactory to the Representatives, confirming that the Securities have such ratings; and since the date of this Agreement, there shall not have occurred a downgrading in the rating assigned to the Securities or any of the Company’s other securities by any “nationally recognized statistical rating agency,” as that term is defined by the Commission for purposes of Section 3(a)(62) under the 1934 Act, and no such securities rating agency shall have publicly announced that it has under surveillance or review, with possible negative implications, its rating of the Securities or any of the Company’s other securities.

(i) Additional Documents. At the Closing Time, counsel for the Underwriters shall have been furnished with such documents and opinions (including but not limited to those referenced above) as they may reasonably 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 reasonably satisfactory in form and substance to the Representatives and counsel for the Underwriters.

(j) Termination of Agreement. If any condition specified in this Section 5 shall not have been fulfilled when and as required to be fulfilled, this Agreement may be terminated by the Representatives by notice to the Company at any time at or prior to the Closing Time, and such termination shall be without liability of any party to any other party except as provided in Section 4 and except that Sections 1, 6, 7, 8 and 15 shall survive any such termination and remain in full force and effect.

SECTION 6. Indemnification.

(a) Indemnification of Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, directors, officers and employees 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, arising out of any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement (or any amendment thereto), 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, 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;

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(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; and

(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 clause (i) or (ii) above;

provided, however, that this indemnity 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), or any preliminary prospectus, Issuer Free Writing Prospectus or the Prospectus (or any amendment or supplement thereto), it being understood and agreed that the only such information consists of the information contained in Schedule E hereto.

(b) Indemnification of Company, Directors and Officers. Each Underwriter severally agrees to indemnify and hold harmless the Company, its affiliates, 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 6, 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) or any preliminary prospectus, 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, it being understood and agreed that the only such information consists of the information contained in Schedule E hereto.

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(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. In the case of parties indemnified pursuant to Section 6(a) above, counsel to the indemnified parties shall be selected by the Representatives, and, in the case of parties indemnified pursuant to Section 6(b) above, counsel to the indemnified parties shall be selected by the Company. An indemnifying party may participate at its own expense in the defense of any such action; provided, however, that counsel to the indemnifying party shall not (except with the consent of the indemnified party) also be counsel to the indemnified party. In no event shall the indemnifying parties be liable for fees and expenses of more than one counsel (in addition to any local counsel) separate from their own counsel for all indemnified parties in connection with any one action or separate but similar or related actions in the same jurisdiction arising out of the same general allegations or circumstances. In addition, the indemnifying party shall be entitled, to the extent that it wishes, jointly with any other similarly notified indemnifying party, to assume the defense of any claim or action brought against an indemnified party with counsel reasonably satisfactory to the indemnified party. After notice from the indemnifying party to the indemnified party of its election to assume the defense of such claim or action, the indemnifying party shall not be liable to the indemnified party under this Section 6 for any legal or other expenses subsequently incurred by the indemnified party in connection with the defense thereof other than reasonable costs of investigation; provided, however, that the Representatives shall have the right to employ one counsel (in addition to local counsel) to represent them and those other Underwriters and their respective officers, employees and controlling persons who may be subject to liability arising out of any claim in respect of which indemnity may be sought by the Underwriters against the Company under this Section 6 if, in the reasonable judgment of the Representatives, either (i) there is an actual or potential conflict between the position of the Company on the one hand and the Underwriters on the other hand or (ii) there may be defenses available to it or them that are different from or additional to those available to the Company (in any of which events the Company shall not have the right to direct the defense of such action on behalf of the Representatives with respect to such different defenses), in any of which events such reasonable fees and expenses shall be borne by the Company. No indemnifying party shall, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any litigation, or any investigation or proceeding by any governmental agency or body, commenced or threatened, or any claim whatsoever in respect of which indemnification or contribution could be sought under this Section 6 or Section 7 hereof (whether or not the indemnified parties are actual or potential parties thereto), unless such settlement, compromise or consent (A) includes an unconditional release of each indemnified party from all liability arising out of such litigation, investigation, proceeding or claim and (B) 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.

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(d) Settlement without Consent if Failure to Reimburse. If at any time an indemnified party shall have requested an indemnifying party to reimburse the indemnified party for fees and expenses of counsel, such indemnifying party agrees that it shall be liable for any settlement of the nature contemplated by Section 6(a)(ii) effected without its written consent if (i) such settlement is entered into more than 45 days after receipt by such indemnifying party of the aforesaid request, (ii) such indemnifying party shall have received notice of the terms of such settlement at least 30 days prior to such settlement being entered into and (iii) such indemnifying party shall not have reimbursed such indemnified party in accordance with such request prior to the date of such settlement.

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, (a) 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 (b) if the allocation provided by clause (a) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (a) 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 initial public offering price of the Securities as set forth on such cover.

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.

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Notwithstanding the provisions of this Section 7, no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Securities underwritten by it and distributed to the public were offered to the public exceeds the amount of any damages which such Underwriter has otherwise been required to pay by reason of any such untrue or alleged untrue statement or omission or alleged omission.

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 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 principal amount of Securities set forth opposite their respective names in Schedule A hereto and not joint.

SECTION 8.    Representations, Warranties and Agreements to Survive Delivery. All representations, warranties and agreements contained in this Agreement or in certificates of officers of the Company or any of its subsidiaries submitted pursuant hereto, shall remain operative and in full force and effect, regardless of any investigation made by or on behalf of any Underwriter or controlling person, or by or on behalf of the Company, and shall survive delivery of and payment for the Securities to the Underwriters.

SECTION 9. Termination of Agreement.

(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 General Disclosure Package, any material adverse change in the condition, financial or otherwise, in the earnings or business affairs of the Company and its subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business, or any developments involving a prospective material adverse change of the Company and its subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business, (ii) if there has occurred after the date hereof and prior to the Closing Time 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, in each case the effect of which is such as to make it, in the reasonable judgment of the Representatives, impracticable to market the Securities or to enforce contracts for the sale of the Securities, (iii) if trading in any securities of the Company or the Parent has been suspended or materially limited by the Commission or the New York Stock Exchange, or if trading generally on the NYSE American or the New York Stock Exchange or the Nasdaq Global Market has

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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 Financial Industry Regulatory Authority or any other governmental authority, (iv) if a banking moratorium has been declared by either Federal or New York authorities or (v) if a material disruption has occurred in securities settlement or clearance services in the United States.

(b) Liabilities. If this Agreement is terminated pursuant to this Section 9, such termination shall be without liability of any party to any other party except as provided in Section 4 hereof, and provided further that Sections 1, 6, 7, 8 and 15 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 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:

(a) if the aggregate principal amount of Defaulted Securities does not exceed 10% of the aggregate principal amount 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

(b) if the aggregate principal amount of Defaulted Securities exceeds 10% of the aggregate principal amount of Securities to be purchased on such date, this Agreement shall terminate without liability on the part of any non-defaulting Underwriter.

No action taken pursuant to this Section 10 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, either the Representatives or the Company shall have the right to postpone the Closing Time 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.

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SECTION 11.    Certain Agreements of the Underwriters. Each Underwriter hereby represents and agrees that:

(a) it has not used, authorized the use of, referred to or participated in the planning for use of, and will not use, authorize the use of, refer to or participate in the planning for use of, any “free writing prospectus”, as defined in Rule 405 of the 1933 Act Regulations (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) other than (i) a free writing prospectus that contains no “issuer information” (as defined in Rule 433(h)(2) of the 1933 Act Regulations) that was not included (including through incorporation by reference) in any preliminary prospectus or a previously filed Issuer Free Writing Prospectus, (ii) any Issuer Free Writing Prospectus listed on Schedule B or prepared pursuant to Section 3(o) above (including any electronic road show), (iii) any free writing prospectus prepared by such underwriter and approved by the Company in advance in writing, or (iv) any free writing prospectus prepared by or on behalf of such underwriter that would not be required to be filed with the Commission;

(b) it has not and will not, without the prior written consent of the Company, use any free writing prospectus that contains the final terms of the Securities, unless such terms have previously been included in a free writing prospectus filed with the Commission; provided that the Underwriters may use a term sheet substantially in the form of Schedule D hereto without the consent of the Company; provided, further, that any Underwriter using such term sheet shall notify the Company, and provide a copy of such term sheet to the Company, prior to, or substantially concurrently with, the first use of such term sheet and, provided, further, that nothing in this Section 11 shall prevent the Underwriters from transmitting or otherwise making use of one or more customary “Bloomberg Screens” to offer the Securities or convey final pricing terms thereof that contain only information contained in the term sheet attached as Schedule D hereto;

(c) (i) it has only communicated or caused to be communicated and will only communicate or cause to be communicated an invitation or inducement to engage in investment activity (within the meaning of Section 21 of the U.K. Financial Services and Markets Act of 2000 (the “FSMA”)) received by it in connection with the issue or sale of the Securities in circumstances in which Section 21(1) of the FSMA does not apply to the Company; and (ii) it has complied with and will comply with all applicable provisions of the FSMA with respect to anything done by it in relation to the Securities in, from or otherwise involving the United Kingdom; and

(d) solely in connection with the offering of the Securities, it has not made and will not make an offer of, or otherwise made or will make available, the Securities to any retail investor in the European Economic Area. For the purposes of this provision, “a retail investor” means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU (as amended, “MiFID II”); or (ii) a customer within the meaning of Directive 2002/92/EC, as amended, where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in Directive 2003/71/EC.

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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 the Representatives at:

Barclays Capital Inc.

745 Seventh Avenue

New York, NY 10019

Attn: Syndicate Registration

Fax: (646) 834-8133

J.P. Morgan Securities LLC

383 Madison Avenue

New York, NY 10179

Attn: Investment Grade Syndicate Desk

Fax: (212) 834-6081

Mizuho Securities USA LLC

320 Park Avenue

New York, NY 10022

Attn: Debt Capital Markets

Fax: (212) 205-7812

and notices to the Company shall be directed to it at 4902 North Biltmore Lane, Madison, Wisconsin 53718, attention of Robert J. Durian, Senior Vice President and Chief Financial Officer, or his successor (telephone: (608) 458-3449; facsimile: (608) 458-0132).

SECTION 13.    Parties. This Agreement shall inure to the benefit of and be binding upon each of the Underwriters and the Company 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 and the Company 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 and the Company 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 14.    No Fiduciary Duty.    The Company hereby acknowledges that the Underwriters will be acting pursuant to a contractual relationship on an arm’s length basis and in no event do the parties intend that the Underwriters act or be responsible as a fiduciary to the Company, its management, stockholders, creditors or any other person. The Company and the Underwriters each hereby expressly disclaim any fiduciary relationship and agree they are each responsible for making their own independent judgments with respect to any transactions entered into between them.

SECTION 15.    GOVERNING LAW AND TIME. THIS AGREEMENT AND ALL DISPUTES, CONTROVERSIES OR CLAIMS ARISING OUT OF OR RELATING TO THIS AGREEMENT OR A BREACH HEREOF SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK. EXCEPT AS OTHERWISE SET FORTH HEREIN, SPECIFIED TIMES OF DAY REFER TO NEW YORK CITY TIME.

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SECTION 16.    Patriot Act. In accordance with the requirements of the USA Patriot Act (Title III of Pub. L, 107-56 (signed into law October 26, 2001)), the Underwriters are required to obtain, verify and record information that identifies their clients, which may include the name and address of their clients, as well as other information that will allow the Underwriters to properly identify their clients.

SECTION 17.    Recognition of the U.S. Special Resolution Regimes.

(a) In the event that any Underwriter that is a Covered Entity (as defined below) becomes subject to a proceeding under a U.S. Special Resolution Regime (as defined below), the transfer from such Underwriter of this Agreement, and any interest and obligation in or under this Agreement, will be effective to the same extent as the transfer would be effective under the U.S. Special Resolution Regime if this Agreement, and any such interest and obligation, were governed by the laws of the United States or a state of the United States.

(b) In the event that any Underwriter that is a Covered Entity or a BHC Act Affiliate (as defined below) of such Underwriter becomes subject to a proceeding under a U.S. Special Resolution Regime, Default Rights (as defined below) under this Agreement that may be exercised against such Underwriter are permitted to be exercised to no greater extent than such Default Rights could be exercised under the U.S. Special Resolution Regime if this Agreement were governed by the laws of the United States or a state of the United States.

For purposes of this Section 17:

“BHC Act Affiliate” has the meaning assigned to the term “affiliate” in, and shall be interpreted in accordance with, 12 U.S.C. § 1841(k).

“Covered Entity” means any of the following:

i. a “covered entity” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 252.82(b);

ii. a “covered bank” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 47.3(b); or

iii. a “covered FSI” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 382.2(b).

“Default Right” has the meaning assigned to that term in, and shall be interpreted in accordance with, 12 C.F.R. §§ 252.81, 47.2 or 382.1, as applicable.

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“U.S. Special Resolution Regime” means each of (i) the Federal Deposit Insurance Act and the regulations promulgated thereunder and (ii) Title II of the Dodd-Frank Wall Street Reform and Consumer Protection Act and the regulations promulgated thereunder.

SECTION 18.    Effect of Headings. The Article and Section headings herein and the Table of Contents are for convenience only and shall not affect the construction hereof.

SECTION 19.    Counterparts. This Agreement may be executed in one or more counterparts and, if executed in more than one counterpart, the executed counterparts shall constitute a single instrument.

[Signature page follows]

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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 between the Underwriters and the Company in accordance with its terms.

Very truly yours,
INTERSTATE POWER AND LIGHT COMPANY
By:	/s/ Robert J. Durian
	Name: Robert J. Durian Title:   Senior Vice President and             Chief Financial Officer

[Signature Page to Underwriting Agreement]

CONFIRMED AND ACCEPTED,

as of the date first above written:

BARCLAYS CAPITAL INC.
By:	/s/ Robert Stowe
	Name: Robert Stowe Title:   Managing Director

J.P. MORGAN SECURITIES LLC
By:	/s/ Som Bhattacharyya
	Name: Som Bhattacharyya Title:   Executive Director

MIZUHO SECURITIES USA LLC
By:	/s/ Scott Trachsel
	Name: Scott Trachsel Title:   Managing Director

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

[Signature Page to Underwriting Agreement]

SCHEDULE A

LIST OF UNDERWRITERS’ PURCHASE AMOUNTS

Name of Underwriter	Principal amount of Securities to be purchased
Barclays Capital Inc.	$	80,000,000
J.P. Morgan Securities LLC		80,000,000
Mizuho Securities USA LLC		80,000,000
KeyBanc Capital Markets Inc.		20,000,000
Samuel A. Ramirez & Company, Inc.		20,000,000
U.S. Bancorp Investments, Inc.		20,000,000
Total	$	300,000,000

SCHEDULE B

ISSUER FREE WRITING PROSPECTUSES

Final Term Sheet, dated as of March 25, 2019

SCHEDULE C

PRICING INFORMATION

1.    The initial public offering price of the Securities shall be 99.867% of the principal amount thereof, plus accrued interest, if any, from the date of issuance.

2.    The purchase price to be paid by the Underwriters for the Securities shall be 99.217% of the principal amount thereof.

3.    The interest rate on the Securities shall be 3.60% per annum.

4.    At any time prior to January 1, 2029 (the “Par Call Date”), the Securities will be redeemable as a whole or in part, at the Company’s option, at a redemption price equal to the greater of (i) 100% of the principal amount of such Securities and (ii) the sum, as determined by the Independent Investment Banker and delivered to the Trustee, of the present values of the remaining scheduled payments of principal and interest thereon that would be due if the Securities matured on the Par Call Date (exclusive of interest accrued to the date of redemption) discounted to the redemption date on a semiannual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus 20 basis points, plus in each case accrued and unpaid interest, if any, to, but excluding, the redemption date. On or after the Par Call Date, the Securities will be redeemable as a whole or in part, at the Company’s option, at a redemption price equal to 100% of the principal amount of the Securities being redeemed plus accrued and unpaid interest, if any, to, but excluding, the redemption date.

“Comparable Treasury Issue” means the United States Treasury security or securities selected by an Independent Investment Banker as having an actual or interpolated maturity comparable to the remaining term of the Securities (assuming for this purpose that the Securities matured on the applicable Par Call Date) to be redeemed that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of a comparable maturity to the remaining term of such Securities.

“Comparable Treasury Price” means, with respect to any redemption date, (A) the average of the Reference Treasury Dealer Quotations for such redemption date, after excluding the highest and lowest such Reference Treasury Dealer Quotations, or (B) if the Independent Investment Banker obtains fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations.

“Independent Investment Banker” means one of the Reference Treasury Dealers appointed by the Company.

“Reference Treasury Dealer” means each of (i) Barclays Capital Inc., (ii) J.P. Morgan Securities LLC, (iii) Mizuho Securities USA LLC and (iv) a primary U.S. Government securities dealer located in the United States (a “Primary Treasury Dealer”) selected by the Company, and such Primary Treasury Dealers’ respective successors; provided, however, that if any of the foregoing or their affiliates shall cease to be a Primary Treasury Dealer, the Company shall substitute therefor another Primary Treasury Dealer.

“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any redemption date, the average, as determined by the Independent Investment Banker, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Independent Investment Banker by the Reference Treasury Dealers at 3:30 P.M. New York time on the third business day preceding such redemption date.

“Treasury Rate” means, with respect to any redemption date, the rate per annum equal to the semiannual equivalent yield to maturity or interpolated (on a day count basis) of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such redemption date.

SCHEDULE D

INTERSTATE POWER AND LIGHT COMPANY

$300,000,000 3.60% Senior Debentures due 2029

Final Term Sheet

Dated March 25, 2019

Issuer:	Interstate Power and Light Company
Security Type:	Senior Debentures
Principal Amount:	$300,000,000
Maturity Date:	April 1, 2029
Coupon:	3.60%
Price to Public:	99.867% of the principal amount
Yield to Maturity:	3.616%
Benchmark Treasury:	2.625% UST due February 15, 2029
Benchmark Treasury Yield:	2.416%
Spread to Benchmark Treasury:	+120 bps
Interest Payment Dates:	April 1 and October 1, commencing on October 1, 2019
Optional Redemption — Reinvestment Rate:	Prior to January 1, 2029, make-whole call at Treasury +20 bps
Optional Redemption at Par:	On or after January 1, 2029
Trade Date:	March 25, 2019
Settlement Date:	April 1, 2019 (T+5)
CUSIP:	461070 AQ7
ISIN:	US461070AQ74
Anticipated Ratings*:	[intentionally omitted]
Joint Book-Running Managers:	Barclays Capital Inc. J.P. Morgan Securities LLC Mizuho Securities USA LLC
Co-Managers:	KeyBanc Capital Markets Inc. U.S. Bancorp Investments, Inc. Samuel A. Ramirez & Company, Inc.

* A securities rating is not a recommendation to buy, sell or hold securities and may be subject to revision or withdrawal at any time.

It is expected that delivery of the Debentures will be made against payment therefor on or about April 1, 2019, which will be the fifth business day following the date of pricing of the Debentures. Under Rule 15c6-1 of the Securities Exchange Act of 1934, trades in the secondary market generally are required to settle in two business days, unless the parties to any such trade expressly agree otherwise. Accordingly, by virtue of the fact that the Debentures initially will settle in T+5, purchasers who wish to trade the Debentures on the date of pricing of the Debentures or on the two succeeding business days should specify an extended settlement cycle at the time they enter into any such trade to prevent failed settlement and should consult their own advisors.

The issuer has filed a registration statement (including a prospectus) with the Securities & Exchange Commission (the “SEC”) for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents that the issuer has filed with the SEC for more complete information about the issuer and this offering. You may get these documents for free by visiting EDGAR on the SEC Web site at www.sec.gov. Alternatively, you may request a copy of these documents by calling Barclays Capital Inc. toll-free at (888) 603-5847, J.P. Morgan Securities LLC collect at 1-212-834-4533, or Mizuho Securities USA LLC toll-free at (866) 271-7403.

Any disclaimers or other notices that may appear below are not applicable to this communication and should be disregarded. Such disclaimers and other notices were automatically generated as a result of this communication being sent via Bloomberg or another email system.

SCHEDULE E

UNDERWRITER INFORMATION

1.    The statements set forth in the first paragraph under the heading “Commissions and Discounts” in the section titled “Underwriting” in the Prospectus and in any preliminary prospectus.

2.    The statements set forth in the first and second paragraphs under the heading “Price Stabilization and Short Position” in the section titled “Underwriting” in the Prospectus and in any preliminary prospectus.

EX-4.1

Exhibit 4.1

INTERSTATE POWER AND LIGHT COMPANY

OFFICER’S CERTIFICATE

Dated as of April 1, 2019

Setting Forth Terms of a Series of Debt Securities

3.60% Senior Debentures due 2029

Pursuant to the Indenture

Dated as of August 20, 2003

OFFICER’S CERTIFICATE

The undersigned, the Senior Vice President and Chief Financial Officer of Interstate Power and Light Company, an Iowa corporation (the “Company”), hereby certifies as provided below pursuant to Section 301 of the Indenture, dated as of August 20, 2003 (the “Indenture”), between the Company and The Bank of New York Mellon Trust Company, N.A., as Trustee (the “Trustee”). This Officer’s Certificate, dated April 1, 2019, is delivered, pursuant to authority granted to the undersigned by the resolutions adopted on October 31, 2018 by the Board of Directors of the Company, for the purpose of creating and setting forth the terms of a series of Securities to be issued pursuant to the Indenture, and to establish the form of such Securities in accordance with Section 201 of the Indenture. Capitalized terms not otherwise defined herein are used as defined in the Indenture.

1.    The Board of Directors of the Company has authorized the creation by the Company of one or more series of Securities under the Indenture through one or more Officer’s Certificates and pursuant to such authorization and in accordance with the Indenture this Officer’s Certificate is being delivered to the Trustee to establish the terms of a series of Securities as set forth therein and herein.

2.    The title of the series of Securities shall be “3.60% Senior Debentures due 2029” (herein called the “Debentures”).

3.    The aggregate principal amount of the Debentures which may be authenticated and delivered under the Indenture shall be U.S. $300,000,000, except for Debentures authenticated and delivered upon registration of transfer of, or in exchange for, or in lieu of, other Debentures as provided in Sections 304, 305, 306, 406 or 1206 of the Indenture. Notwithstanding the foregoing limit on the aggregate principal amount of the Debentures, the Debentures may be reopened in accordance with Section 301 of the Indenture.

4.    The Debentures shall be issuable in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

5.    Subject to earlier redemption, the principal of the Debentures shall be payable in U.S. dollars on April 1, 2029.

6.    The Debentures shall bear interest at the rate of 3.60% per annum; such interest shall accrue from April 1, 2019 (or from and including the most recent Interest Payment Date to which interest on the Debentures has been paid or provided for); the Interest Payment Dates on which such interest shall be payable shall be April 1 and October 1 in each year, commencing October 1, 2019; the Regular Record Dates for the determination of Holders to whom interest is payable shall be the fifteenth calendar day before each Interest Payment Date. Interest on the Debentures shall be payable in U.S. dollars.

7.    Pursuant to the Indenture, the Trustee has been appointed as the Security Registrar for the Debentures. The Trustee is hereby further appointed as the initial Paying Agent and Transfer Agent of the Debentures. The principal of and interest on the Debentures shall be payable at the office of the Paying Agent, which shall initially be located in the Borough of Manhattan, The City of New York.

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8.    At any time or from time to time prior to January 1, 2029 (the “Par Call Date”), the Debentures shall be redeemable at the option of the Company in whole or in part at a Redemption Price equal to the greater of (i) 100% of the principal amount of such Debentures and (ii) the sum, as determined by the Independent Investment Banker and delivered to the Trustee, of the present values of the remaining scheduled payments of principal and interest thereon that would be due if the Debentures matured on the Par Call Date (exclusive of interest accrued to the Redemption Date) discounted to the Redemption Date on a semiannual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus 20 basis points, plus in each case accrued and unpaid interest to, but excluding, the Redemption Date; provided, however, that installments of interest on Debentures due on an Interest Payment Date which occurs on or before any Redemption Date shall be payable to the Holders of such Debentures who were registered Holders as of the close of business on the Regular Record Date immediately preceding such Interest Payment Date. At any time on or after the Par Call Date, the Debentures shall be redeemable at the option of the Company in whole or in part at a Redemption Price equal to 100% of the principal amount of the Debentures being redeemed, plus accrued and unpaid interest, if any, to, but excluding, the Redemption Date.

9.    The terms defined below shall, for all purposes of the Debentures under the Indenture and this Officer’s Certificate, have the meanings specified, unless the context clearly otherwise requires or unless otherwise indicated:

“Business Day” means any day other than Saturday, Sunday or a day on which Federal or State banking institutions in the city of the office of the Paying Agent is maintained are authorized or obligated by law, executive order or regulation to close.

“Comparable Treasury Issue” means the United States Treasury security or securities selected by an Independent Investment Banker as having an actual or interpolated maturity comparable to the remaining term of the Debentures (assuming for this purpose that the Debentures matured on the applicable Par Call Date) to be redeemed that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of a comparable maturity to the remaining term of such Debentures.

“Comparable Treasury Price” means, with respect to any Redemption Date, (i) the average of the Reference Treasury Dealer Quotations for such Redemption Date, after excluding the highest and lowest such Reference Treasury Dealer Quotations, or (ii) if the Independent Investment Banker obtains fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations.

“Independent Investment Banker” means one of the Reference Treasury Dealers appointed by the Company.

“Reference Treasury Dealer” means each of (i) Barclays Capital Inc., (ii) J.P. Morgan Securities LLC, (iii) Mizuho Securities USA LLC and (iv) a primary U.S. Government securities dealer located in the United States (a “Primary Treasury Dealer”) selected by the Company, and such Primary Treasury Dealers’ respective successors; provided, however, that if any of the foregoing or their affiliates shall cease to be a Primary Treasury Dealer, the Company shall substitute therefor another Primary Treasury Dealer.

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“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any Redemption Date, the average, as determined by the Independent Investment Banker, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Independent Investment Banker by the Reference Treasury Dealers at 3:30 p.m. New York time on the third Business Day preceding such Redemption Date.

“Treasury Rate” means, with respect to any Redemption Date, the rate per annum equal to the semiannual equivalent yield to maturity or interpolated (on a day count basis) of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such Redemption Date.

10.    The Debentures shall not be subject to any sinking fund and shall not be repurchasable or redeemable at the option of a Holder.

11.    The Debentures shall not be convertible into other securities of the Company or exchangeable for securities of another issuer.

12.    Satisfaction and discharge under Section 701 of the Indenture shall be applicable to the Debentures; provided, however, that prior to any such satisfaction and discharge, the Company shall have delivered to the Trustee an Opinion of Counsel stating that (i) the Company has received from the Internal Revenue Service a letter ruling, or there has been published by the Internal Revenue Service a revenue ruling, or (ii) since the date of execution of this Officer’s Certificate, there has been a change in the applicable Federal income tax law, in either case to the effect that, and based thereon such opinion shall confirm that, the Holders of such Outstanding Securities will not recognize income, gain or loss for Federal income tax purposes as a result of such satisfaction and discharge and will be subject to Federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such satisfaction and discharge had not occurred.

13.    The Debentures shall initially be issued in whole in the form of one or more global Securities. The Depository Trust Company (“DTC”), a clearing agency registered under the Securities Exchange Act of 1934, as amended, shall initially serve as the depositary for such global Security or Securities. For so long as DTC shall be the depositary, all Debentures shall be registered in its name or in the name of a nominee thereof. While the Debentures are evidenced by one or more global Securities, the depositary or its nominee, as the case may be, shall be the sole Holder thereof for all purposes under the Indenture. Neither the Company nor the Trustee shall have any responsibility or obligation to the depositary’s participants or the beneficial owners for whom they act with respect to their receipt from the depositary of payments on the Debentures or notices given under the Indenture. The global Security or Securities provided for hereunder shall bear such legend or legends as may be required from time to time by the depositary.

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14.    Except as herein described, Debentures in definitive form will not be issued. Notwithstanding the foregoing, in the event the Company decides to discontinue the use of global Securities, any Event of Default has occurred and is continuing or DTC is at any time unwilling, unable or ineligible to continue as depositary and a successor depositary is not appointed by the Company within 90 days, the Company shall issue individual Debentures in certificated form to owners of “book-entry” ownership interests in exchange for the Debentures held by DTC or its nominee, as the case may be. In such instance, an owner of a “book-entry” ownership interest will be entitled to physical delivery of certificates equal in principal amount to such “book-entry” ownership interest and to have such certificates registered in its name. Individual certificates so issued will be issued in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

15.    Additional terms regarding the Debentures are as set forth in the form of the Debentures set forth below.

16.    The form of the Debentures shall be substantially as follows:

Unless this certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company (as defined below) or its agent for registration of transfer, exchange or payment, and any certificate issued is registered in the name of Cede & Co. or in such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein.

INTERSTATE POWER AND LIGHT COMPANY

3.60% SENIOR DEBENTURES DUE 2029

No. R-1 $300,000,000

CUSIP 461070 AQ7

INTERSTATE POWER AND LIGHT COMPANY, a corporation duly organized and existing under the laws of the State of Iowa (herein called the “Company,” which term includes any successor Person under the Indenture hereinafter referred to), for value received, hereby promises to pay to Cede & Co., or registered assigns, the principal sum of THREE HUNDRED MILLION DOLLARS ($300,000,000) on April 1, 2029 and to pay interest on said principal sum from April 1, 2019, or from and including the most recent interest payment date to which interest has been paid or duly provided for, semi-annually, in arrears, on April 1 and October 1 of each year (each such date, an “Interest Payment Date”), commencing October 1, 2019 at the rate of 3.60% per annum to, excluding the date on which the principal hereof is paid or made available for payment. The amount of interest payable for any period will be computed on the basis of twelve 30-day months and a 360-day year. The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date will, as provided in the Indenture, be paid to the Person in whose name this Debenture (or one or more Predecessor Securities, as defined in the Indenture) is registered at the close of business, on the Regular Record Date for such interest,

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which shall be the fifteenth calendar day before each Interest Payment Date. Any such interest installment not so punctually paid or duly provided for shall forthwith cease to be payable to the registered Holder on such Regular Record Date and may either be paid to the Person in whose name this Debenture (or one or more Predecessor Securities) is registered at the close of business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders of Debentures not later than 10 days prior to such Special Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Debenture may be listed, or any book-entry system which may be applicable to this Debenture and upon such notice as may be required by such exchange or system, all as more fully provided in the Indenture.

Payment of the principal of and interest on any Debenture that is not a global Debenture will be made at the office or agency of the Company maintained for that purpose in The City of New York; provided, however, that at the option of the Company payment of interest may be made (i) by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register or (ii) by wire transfer in immediately available funds at such place and to such account as may be designated by the Person entitled thereto as specified in the Security Register. Payment of principal of and interest on any global Debenture will be made to DTC or its nominee, as the case may be, as the sole registered owner and the sole Holder of the global Debenture for all purposes under the Indenture. Payment of the principal of and interest on this Debenture will be made in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts.

Additional provisions of this Debenture are continued on the two pages following the execution and authentication of this Debenture and such provisions have the same effect as though fully set forth in this place.

Unless the certificate of authentication hereon has been executed by or on behalf of the Trustee by manual signature, this Debenture shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

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IN WITNESS WHEREOF, INTERSTATE POWER AND LIGHT COMPANY has caused this instrument to be duly executed under its corporate seal.

Dated: April 1, 2019

INTERSTATE POWER AND LIGHT COMPANY
By:
	Name: Robert J. Durian Title:   Senior Vice President and             Chief Financial Officer

Attest:

Authorized Officer

[Signature Page to Global Debentures]

Trustee’s Certificate of Authentication

This is one of the Debentures of the series designated herein referred to in the within-mentioned Indenture.

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.,     as Trustee
By:
	Name: Title:

[Signature Page to Global Debentures]

INTERSTATE POWER AND LIGHT COMPANY

3.60% Senior Debentures due 2029

This Debenture is one of a duly authorized issue of Debentures of the Company, designated as its “3.60% Senior Debentures due 2029” (herein called the “Debentures”), in aggregate principal amount of $300,000,000, issued under an Indenture, dated as of August 20, 2003 (herein called the “Indenture”), between the Company and The Bank of New York Mellon Trust Company, N.A., successor, as Trustee (the “Trustee”), to which Indenture and the Officer’s Certificate, dated April 1, 2019 (herein called the “Officer’s Certificate”), setting forth the terms and conditions of the Debentures, reference is hereby made for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Trustee, the Company and the Holders of the Debentures, and of the terms upon which the Debentures are, and are to be, authenticated and delivered.

At any time or from time to time prior to January 1, 2029 (the “Par Call Date”), the Debentures shall be redeemable at the option of the Company, in whole or in part, at a Redemption Price equal to the greater of (i) 100% of the principal amount of such Debentures and (ii) the sum, as determined by the Independent Investment Banker and delivered to the trustee, of the present values of the remaining scheduled payments of principal and interest thereon that would be due if the Debentures matured on the Par Call Date (exclusive of interest accrued to the Redemption Date) discounted to the Redemption Date on a semiannual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus 20 basis points, plus in each case accrued and unpaid interest to, but excluding, the Redemption Date. Notice of redemption will be given as provided in the Indenture to the Holder of the Debentures to be redeemed not less than 30 nor more than 60 days prior to the Redemption Date. At any time or after the Par Call Date, the Debentures shall be redeemable at the option of the Company, in whole or in part, at a Redemption Price equal to 100% of the principal amount of the Debentures being redeemed plus accrued and unpaid interest if any, to, but excluding, the Redemption Date.

If an Event of Default with respect to the Debentures shall occur and be continuing, the principal of the Debentures may be declared due and payable in the manner, with the effect and subject to the conditions, provided in the Indenture.

The Indenture contains provisions for satisfaction and discharge at any time of the entire indebtedness of this Debenture upon compliance by the Company with certain conditions set forth in the Indenture.

The Indenture contains provisions permitting the Company and the Trustee, with the consent of the Holders of not less than a majority in principal amount of the Outstanding Securities of all series affected, voting as one class, to modify the Indenture in a manner affecting the rights of the Holders of the Debentures; provided that no such modification may, without the consent of the Holder of each Outstanding Debenture, (i) change the Stated Maturity of, the principal of, or any installment of principal of or interest on (except as provided in Section 312 of the Indenture), any Debenture, or reduce the principal amount thereof or the rate of interest thereon (or the amount of any installment of interest thereon) or change the method of

9

calculating such rate or reduce any premium payable upon the redemption thereof, or change the coin or currency (or other property), in which the Debentures or any premium or the interest thereon is payable, or impair the right to institute suit for the enforcement of any such payment on or after the Stated Maturity of any Debenture or (ii) reduce the percentage in principal amount of the Outstanding Debentures of any series or any Tranche thereof, the consent of the Holders of which is required for any such modification of the Indenture. The Indenture also contains provisions permitting Holders of specified percentages in principal amount of the Debentures at the time Outstanding, on behalf of the Holders of all Debentures, to waive compliance by the Company with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Debenture shall be conclusive and binding upon such Holder and upon all future Holders of this Debenture and of any Debenture issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Debenture.

No reference herein to the Indenture and no provision of this Debenture or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and interest on this Debenture at the times, place and rate, and in the coin or currency, herein prescribed.

As provided in the Indenture and subject to certain limitations, including, if this Debenture is a global Debenture, the limitations set forth on the first page hereof, therein set forth, the transfer of this Debenture is registrable in the Security Register, upon surrender of this Debenture for registration of transfer at the office or agency of the Company in The City of New York maintained for such purpose, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Company and the Security Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Debentures, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees. No service charge shall be made for any such registration of transfer or exchange, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

Prior to due presentment of this Debenture for registration of transfer, the Company, the Trustee and any agent of the Trustee may treat the Person in whose name this Debenture is registered as the owner hereof for all purposes, whether or not this Debenture be overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the contrary.

The Debentures are issuable only in registered form without coupons in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

All terms used in this Debenture which are defined in the Indenture, as supplemented by the Officer’s Certificate, shall have the meanings set forth therein.

THIS DEBENTURE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO CONFLICTS OF LAWS PRINCIPLES THEREOF.

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IN WITNESS WHEREOF, the undersigned has set his hand as of the day and year first above written.

INTERSTATE POWER AND LIGHT COMPANY
By:	/s/ Robert J. Durian
	Name: Robert J. Durian Title:   Senior Vice President and             Chief Financial Officer

[Signature Page to Officer’s Certificate (Pursuant to the Indenture)]

EX-5.1

Exhibit 5.1

April 1, 2019

Interstate Power and Light Company

Alliant Energy Tower

Cedar Rapids, Iowa 52401

Re: 3.60% Senior Debentures due 2029

Registration Statement on Form S-3

Registration No. 333-222076-02

Ladies and Gentlemen:

We have acted as counsel to Interstate Power and Light Company, an Iowa corporation (the “Company”), in connection with the issuance and sale by the Company of $300,000,000 aggregate principal amount of the Company’s 3.60% Senior Debentures due 2029 (the “Debentures”), to be issued pursuant to an indenture dated as of August 20, 2003 (the “Indenture”), between the Company and The Bank of New York Mellon Trust Company, N.A., as successor trustee (the “Trustee”), and the related Officer’s Certificate (the “Officer’s Certificate”) to be dated as of April 1, 2019, which will establish and set forth certain terms and conditions of the Debentures, and subject to the terms and conditions of the Underwriting Agreement dated March 25, 2019 by and between the Company and Barclays Capital Inc., J.P. Morgan Securities LLC and Mizuho Securities USA LLC, as representatives (the “Underwriting Agreement”). The Debentures are being offered and sold under a registration statement on Form S-3 under the Securities Act of 1933, as amended (the “Securities Act”), filed with the Securities and Exchange Commission (the “Commission”) on December 15, 2017 (File No. 333-222076-02) (the “Registration Statement”), including a base prospectus dated December 15, 2017 (the “Base Prospectus”), and a prospectus supplement dated March 25, 2019 (the “Prospectus Supplement,” and together with the Base Prospectus, the “Prospectus”) filed with the Commission pursuant to Rule 424(b) under the Securities Act.

In such capacity, we have examined: (i) the Underwriting Agreement; (ii) the Registration Statement; (iii) the Prospectus; (iv) the form of the Officer’s Certificate; (v) the form of the Debentures; (vi) certain resolutions of the Company’s Board of Directors; (vii) the Indenture; (viii) the Company’s Amended and Restated Articles of Incorporation, as currently in effect; (ix) the Company’s Amended and Restated Bylaws, as currently in effect; and (x) such other proceedings, documents and records as we have deemed necessary or advisable for purposes of this opinion (such items, collectively, the “Transaction Documents”). In such examination, we have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to the original documents of all documents submitted to us as copies and the authenticity of the originals of such latter documents. As to any facts material to our opinion, we have, when relevant facts were not independently established, relied on the Transaction Documents. We have assumed that the Indenture has been duly authorized, executed and delivered by the predecessor to the Trustee, that the Company is validly existing and has the power to enter into the Indenture and the Debentures, and that the Indenture and Debentures have been duly authorized, executed, and delivered by the Company.

Interstate Power and Light Company

April 1, 2019

Page 2

Based upon and subject to limitations, qualifications and assumptions set forth herein, we are of the opinion that the Debentures, when duly executed and authenticated in accordance with the provisions of the Indenture and the Officer’s Certificate and delivered and paid for as contemplated by the Underwriting Agreement and the Prospectus, will be valid and binding obligations of the Company, subject to and limited by the effect of bankruptcy, insolvency, reorganization, receivership, conservatorship, arrangement, moratorium, fraudulent transfer or other laws affecting or relating to the rights of creditors generally and rules governing the availability of injunctive relief or other equitable remedies and general principles of equity, regardless of whether arising prior to or after the date hereof or considered in a proceeding in equity or at law.

We express no opinion concerning any laws other than the laws in their current forms of the State of New York and the federal laws of the United States of America, and we express no opinion with respect to the laws of any other jurisdiction and expressly disclaim responsibility for advising you as to the effect, if any, that the laws of any other jurisdiction may have on the opinions set forth herein.

We hereby consent to the filing of this opinion as an exhibit to the Company’s Current Report on Form 8-K filed April 1, 2019. In giving such consent, we do not thereby concede that we are within the category of persons whose consent is required under Section 7 of the Securities Act or the related rules and regulations of the Commission thereunder.

Very truly yours,

/s/ Perkins Coie LLP

PERKINS COIE LLP

EX-5.2

Exhibit 5.2

April 1, 2019

Interstate Power and Light Company

Alliant Energy Tower

200 First Street S.E.

Cedar Rapids, IA 52401-1409

Re: 3.60% Debentures due 2029

Registration Statement on Form S-3

Registration No. 333-222076-02

Ladies and Gentlemen:

We have acted as special Iowa counsel to Interstate Power and Light Company, an Iowa corporation (the “Company”), for the purpose of delivering this opinion as required under Section 5(b) of the Underwriting Agreement (“Underwriting Agreement”) dated as of March 25, 2019, by and among Barclays Capital Inc., J.P. Morgan Securities LLC and Mizuho Securities USA LLC, as representatives of the Underwriters, and the Company in connection with the issuance of 3.60% Senior Debentures due 2029 of the Company in the aggregate amount of $300,000,000 (“Debentures”). Unless otherwise defined herein, capitalized terms used herein shall have the meanings ascribed to such terms in the Underwriting Agreement.

In our capacity as special counsel, we examined the Underwriting Agreement and such other documents, certificates, corporate and other records and proceedings of the Company relating to the authorization, issuance, and sale of the Debentures in connection with the Underwriting Agreement, and such other legal matters as we deemed pertinent to the opinions hereinafter expressed. As to matters of fact material to our opinions, we have, with your agreement, relied on representations made in the Underwriting Agreement and upon certificates of officers of the Company. We have assumed, with your agreement, the genuineness of all signatures appearing on the documents examined by us, the legal capacity of all natural persons, the genuineness, completeness and authenticity of all documents submitted to us as originals and the conformity with genuine, complete and authentic originals of all documents submitted to us as copies.

Based upon the foregoing, and subject to the qualifications and limitations set forth below, it is our opinion that:

1. Based solely on the Certificate of Existence dated March 22, 2019, issued by the Secretary of State of Iowa, and the bring down of such certificate dated March 25, 2019, collectively attached as Exhibit 1 hereto, the Company is validly existing as a corporation under the laws of the State of Iowa.

2. The Company has the requisite corporate power and authority to execute, deliver and perform all of its undertakings under the Underwriting Agreement and the Debentures.

April 1, 2019

Page 2

3. The Company’s execution, delivery and performance of the Underwriting Agreement and the Debentures, and the consummation by the Company of the transactions described therein have been duly authorized by all necessary corporate action on the part of the Company.

The opinions expressed herein are subject to the following:

A. Our opinion is limited in all respects to the laws of the State of Iowa as currently in effect and no opinion is given with respect to the laws of any jurisdiction other than the State of Iowa.

B. Except as expressly set forth herein, we express no opinion in connection with the transactions contemplated by the Underwriting Agreement or the issuance of the Debentures.

C. We express no opinion regarding any state or federal securities registration or disclosure laws or regulations or state or federal utility laws or regulations.

D. As it relates to the Underwriting Agreement and the transactions contemplated therein, this firm has been engaged by the Company solely for the purpose of rendering the opinions herein expressed.

E. The opinions expressed herein are made as of the date hereof, and we do not undertake to update this opinion with respect to any changes of which we may later become aware.

F. In connection with the opinions expressed above, we have assumed that, at or before the time of the delivery of the Debentures, (i) the Registration Statement shall have been declared effective and such effectiveness shall not have been terminated or rescinded, and (ii) there shall not have occurred any change in law affecting the validity or enforceability of the Debentures.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement on Form S-3 (Registration No. 333-222076-02) filed with the Securities and Exchange Commission (the “Registration Statement”). In giving this consent, we do not thereby admit that we come within the categories of persons whose consent is required under Section 7 of the 1933 Act or under the rules and regulations of the Commission issued thereunder.

Sincerely,

/s/ Simmons Perrine Moyer Bergman PLC

SIMMONS PERRINE MOYER BERGMAN PLC

EX-99.1

Exhibit 99.1

Interstate Power and Light Company

An Alliant Energy Company

Corporate Headquarters

4902 North Biltmore Lane

Madison, WI 53718-2148

News Release

FOR IMMEDIATE RELEASE Media Contact: Scott Reigstad (608) 458-3145 Investor Relations: Susan Gille (608) 458-3956

Interstate Power and Light Company Prices Public Offering of Green Bonds

$300 million in green bonds will be due in 2029

Madison, Wisconsin — March 25, 2019 — Interstate Power and Light Company (“IPL”), a wholly owned subsidiary of Alliant Energy Corporation (NASDAQ: LNT), announced the pricing of its public offering of $300 million aggregate principal amount of 3.60% senior debentures. An amount equal to or in excess of the net proceeds from the offering will be or have been used for the construction and development of wind electric generating facilities. The senior debentures have an interest rate of 3.60% and will be due on April 1, 2029. The closing of the offering is expected to occur on April 1, 2019, subject to customary closing conditions.

The offering was marketed through a group of underwriters consisting of Barclays, J.P. Morgan, and Mizuho Securities as joint book-running managers, and KeyBanc Capital Markets, Ramirez & Co., Inc., and US Bancorp as co-managers.

The offering is being made only by means of a prospectus supplement and accompanying prospectus which are part of a shelf registration statement IPL filed with the Securities and Exchange Commission (the “Commission”). Copies may be obtained from Barclays by calling +1 (888) 603-5847, from J.P. Morgan by calling +1 (212) 834-4533, or from Mizuho Securities by calling +1 (866) 271-7403. Electronic copies of these documents will be available from the Commission’s website at www.sec.gov.

This press release does not constitute an offer to sell or the solicitation of an offer to buy these securities, nor will there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About Alliant Energy

Alliant Energy Corporation’s Iowa utility subsidiary, Interstate Power and Light Company (IPL), utilizes the trade name of Alliant Energy (NASDAQ:LNT). The Iowa utility is based in Cedar Rapids, Iowa.

Forward-Looking Statements

This press release includes forward-looking statements. These statements involve inherent risks and uncertainties that could cause actual results to differ materially from those projected or anticipated, including risks related to the proposed offering, the anticipated use of proceeds from the sale of the senior debentures and other risks outlined in IPL’s public filings with the Commission, including IPL’s most recent annual report on Form 10-K and subsequent Quarterly Reports on Form 10-Q. All information provided in this news release speaks as of the date hereof. Except as otherwise required by law, IPL undertakes no obligation to update or revise its forward-looking statements.