What changed in this filing

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Item 9A. Controls and Procedures

2024-02-16 compared with 2023-02-24 · 86 added, 93 removed, 287 unchanged (38% of the section changed)

12 unchanged sentences

This report does not include an attestation report of IPL’s and WPL’s independent registered public accounting firm regarding its assessment of IPL’s and WPL’s internal control over financial reporting.

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

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In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2023, based on criteria established in Internal Control - Integrated Framework (2013) issued by COSO.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated financial statements as of and for the year ended December 31, 2022, of the Company and our report dated February 24, 2023, expressed an unqualified opinion on those financial statements.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated financial statements as of and for the year ended December 31, 2023, of the Company and our report dated February 16, 2024, expressed an unqualified opinion on the Company’s 2023 financial statements.

Basis for Opinion

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February 16, 2024

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OTHER INFORMATION

During the quarter ended December 31, 2023, no director or officer of Alliant Energy, IPL or WPL adopted or terminated a Rule 10b5-1 trading arrangement or non-Rule 10b5-1 trading arrangement, as each term is defined in Item 408(a) of Regulation S-K.

DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

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The remainder of the information required by Item 12 for Alliant Energy, and the information required by Item 12 for each of IPL and WPL, is incorporated herein by reference to the relevant information in the 2024 Alliant Energy Proxy Statement, which will be filed with the SEC within 120 days after the end of Alliant Energy’s, IPL’s and WPL’s fiscal year.

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CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE

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IPL’s and WPL’s tax fees for 2023 and 2022 consisted of the fees billed for professional services rendered for tax compliance, tax advice and tax planning, including all services performed by the tax professional staff of affiliates of the independent registered public accounting firm, except those rendered in connection with the audit.

All other fees for 2022 and 2021 for IPL and WPL consisted of license fees for accounting research software products and virtual seminars.

All other fees for 2023 and 2022 for IPL and WPL consisted of license fees for accounting research software products and seminars.

The Audit Committee does not consider the provision of non-audit services by the independent registered public accounting firm described above to be incompatible with maintaining independence of the independent registered public accounting firm.

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EXHIBITS, FINANCIAL STATEMENT SCHEDULES

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Total current liabilities 1,235 1,680

Long-term debt, net 568 —

Other liabilities 2 1

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Retained earnings 3,768 3,518

Accumulated other comprehensive income 1 —

Shares in deferred compensation trust ( 13 ) ( 13 )

2 unchanged sentences

Refer to accompanying Notes to Condensed Financial Statements.

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ALLIANT ENERGY CORPORATION (Parent Company Only) Year Ended December 31,

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Net cash flows used for investing activities ( 606 ) ( 161 ) ( 266 )

Cash flows used for financing activities:

Cash flows from (used for) financing activities:

Common stock dividends ( 456 ) ( 428 ) ( 403 )

Proceeds from issuance of common stock, net 246 25 28

Proceeds from issuance of long-term debt 565 — —

Net change in commercial paper ( 195 ) 73 147

Other 1 ( 1 ) —

Net cash flows used for financing activities ( 331 ) ( 228 ) ( 168 )

Net cash flows from (used for) financing activities 161 ( 331 ) ( 228 )

Net increase (decrease) in cash, cash equivalents and restricted cash — — —

11 unchanged sentences

In the Condensed Financial Statements of Alliant Energy Corporation (Parent Company Only), investments in subsidiaries are accounted for using the equity method.

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SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS AND RESERVES

Balance, Charged to Charged to Other Balance,

Description January 1 Expense Accounts (a) Deductions (b) December 31

Balance, (Charged to Balance,

Description January 1 Expense) Deductions (a) December 31

(in millions)

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Accumulated Provision for Uncollectible Accounts:

Alliant Energy (c)

Alliant Energy (b)

Year ended December 31, 2023 $ 7 $ 20 $ 19 $ 8

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The above provisions relate to various customer, notes and other receivable balances included in various line items on the respective balance sheets.

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(a) Accumulated provision for uncollectible accounts:

In accordance with its regulatory treatment, certain amounts provided by WPL are recorded in regulatory assets.

(b) Deductions are of the nature for which the reserves were created.

(a) Deductions are of the nature for which the reserves were created.

In the case of the accumulated provision for uncollectible accounts, deductions from this reserve are reduced by recoveries of amounts previously written off.

(b) Refer to Note 5(b) for discussion of IPL’s sales of accounts receivable program.

All other schedules are omitted because they are not applicable or not required, or because that required information is shown either in the financial statements or in the notes thereto.

11 unchanged sentences

4.1 Amended and Restated Five-Year Master Credit Agreement, effective December 17, 2021 , among Alliant Energy, IPL, WPL, Wells Fargo Bank, National Association (N.A.) and the lender parties set forth therein (incorporated by reference to Exhibit 4.1 to Alliant Energy’s Form 8-K, filed December 21, 20 21 (File No.

4.2 Senior Note Indenture, dated as of September 30, 2009, between Alliant Energy and Wells Fargo Bank, N.A.

(incorporated by reference to Exhibit 4.28 to Alliant Energy’s Registration Statement on Form S-3 (Reg.

4.1a First Amendment to Amended and Restated Five-Year Master Credit Agreement, effective March 15, 2023, among Alliant Energy, IPL, WPL, Wells Fargo Bank, N.A .

and the lender parties set forth therein (incorporated by reference to Exhibit 4.1 to Alliant Energy’s Form 10 - Q for the quarter ended March 31, 202 3 (File No.

4.2 Indenture, dated as of March 2, 2023, between Alliant Energy and The Bank of New York Mellon Trust Company, N.A., as trustee (incorporated by reference to Exhibit 4.1 to Alliant Energy's Form 8-K, filed March 3, 2023 (File No.

4.3 Indenture, dated as of June 12, 2018, among AEF, Alliant Energy, as guarantor, and The Bank of New York Mellon Trust Company, N.A., as trustee (incorporated by reference to Exhibit 4.1 to Alliant Energy’s Form 8-K, filed June 12, 2018 (File No.

4.4 Indenture, dated as of November 20, 2020, among AEF, Alliant Energy as guarantor, and The Bank of New York Mellon Trust Company, N.A., as trustee (incorporated by reference to Exhibit 4.1 to Alliant Energy’s Form 8-K, filed November 23, 2020 (File No.

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Exhibit Number Description

4.5 Indenture, dated as of February 28, 2022, among AEF, Alliant Energy, as guarantor, and The Bank of New York Mellon Trust Company, N.A., as trustee (incorporated by reference to Exhibit 4.1 to Alliant Energy’s Form 8-K, filed March 1, 2022 (File No.

4.6 Indenture, dated as of November 10, 2023, among AEF, Alliant Energy, as guarantor, and The Bank of New York Mellon Trust Company, N.A., as trustee (incorporated by reference to Exhibit 4.1 to Alliant Energy's Form 8-K, filed November 13, 2023 (File No.

4.7 Indenture, dated as of June 20, 1997, between WPL and U.S.

12 unchanged sentences

4.15 Officers’ Certificate, dated as of August 15, 2022, creating WPL’s 3.950% Debentures due September 1, 2032 (incorporated by reference to Exhibit 4.1 to WPL’s Form 8-K, filed August 15, 2022 (File No.

4.16 Officers’ Certificate, dated as of March 30, 2023, creating WPL's 4.950% Debentures due April 1, 2033 (incorporated by reference to Exhibit 4.1 to WPL's Form 8-K, filed March 30, 2023 (File No.

4.17 Indenture (For Senior Unsecured Debt Securities), dated as of August 20, 2003, between IPL and The Bank of New York Mellon Trust Co., N.A.

1 unchanged sentence

4.18 Officer’s Certificate, dated as of October 14, 2003, creating IPL’s 6.45% Senior Debentures due October 15, 2033 (incorporated by reference to Exhibit 4.1 to IPL’s Form 8-K, filed October 15, 2003 (File No.

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Exhibit Number Description

4.19 Officer’s Certificate, dated as of May 3, 2004, creating IPL’s 6.30% Senior Debentures due May 1, 2034 (incorporated by reference to Exhibit 4.1 to IPL’s Form 8-K, filed May 5, 2004 (File No.

12 unchanged sentences

4.30 Officer’s Certificate, dated as of November 19, 2021, creating IPL’s 3.1% Senior Debentures due November 30, 2051 (incorporated by reference to Exhibit 4.1 to IPL’s Form 8-K, filed November 19, 2021 (File No.

4.29 Description of Common Stock of Alliant Energy (incorporated by reference to Exhibit 4.26 to Alliant Energy’s Form 10-K for the year 2019 (File No.

4.31 Officer’s Certificate, dated as of September 21, 2023, creating IPL’s 5.70% Senior Debentures due October 15, 2033 (incorporated by reference to Exhibit 4.1 to IPL’s Form 8-K, filed September 21, 2023 (File No.

4.32 Description of Common Stock of Alliant Energy

10.1 Term Loan Credit Agreement, dated as of March 3, 2022, among AEF, Alliant Energy, U.S.

and the lender parties set forth therein (incorporated by reference to Exhibit 10.1 to Alliant Energy’s Form 8-K, filed March 4, 2022 (File No.

10.1a Incremental Term Loan Amendment, dated as of December 7, 2022, among AEF, Alliant Energy, Co Bank ACB a s incremental le n der, and U.S.

as administrative agent

10.2# Amended and Restated OIP, amended in 2015 (incorporated by reference to Appendix A to Alliant Energy’s definitive proxy statement filed on Schedule 14A on March 24, 2015 (File No.

10.2a# Amendment to the Amended and Restated OIP (incorporated by reference to Exhibit 10.6a to Alliant Energy’s Form 10-K for the year 2018 (File No.

10.2b# Form of Performance Share Agreement pursuant to the Amended and Restated OIP, amended in 2019 (incorporated by reference to Exhibit 10.6c to Alliant Energy’s Form 10-K for the year 2018 (File No.

10.2c# Form of Restricted Stock Unit Agreement pursuant to the Amended and Restated OIP, amended in 2019 (incorporated by reference to Exhibit 10.6e to Alliant Energy’s Form 10-K for the year 2018 (File No.

10.2d# Form of Performance Restricted Stock Unit Agreement pursuant to the Amended and Restated OIP, amended in 2019 (incorporated by reference to Exhibit 10.6g to Alliant Energy’s Form 10-K for the year 2018 (File No.

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Exhibit Number Description

10.1a Incremental Term Loan Amendment, dated as of December 7, 2022, among AEF, Alliant Energy, CoBank ACB as incremental lender, and U.S.

as administrative agent (incorporated by reference to Exhibit 10.1a to Alliant Energy's Form 10-K for the year 2022 (File No .

10.2# 2020 O I P (incorporated by reference to Appendix A to Alliant Energy’s definitive proxy statement filed on Schedule 14A on April 9, 2020 (File No.

6 unchanged sentences

10.2g# Form of Performance Restricted Stock Unit Agreement (Net Income Metric) pursuant to the 2020 OIP, amended in 2022 (incorporated by reference to Exhibit 10.3g to Alliant Energy’s Form 10-K for the year 2021 (File No.

10.2h# Form of Performance Share Agreement pu rsuant to t he 2020 OIP, amended in 2024

10.3# DCP, as amended and restated effective January 1, 2011 (incorporated by reference to Exhibit 10.1 to Alliant Energy’s Form 8-K, filed December 14, 2010 (File No.

10.3a# Amendment to the DCP, as amended and restated (incorporated by reference to Exhibit 10.2 to Alliant Energy’s Form 8-K, filed December 5, 2011 (File No.

10.4b# Amendment to the DCP, as amended and restated

10.3b# Amendment to the DCP, as amended and restated (incorporated by reference to Exhibit 10.4b to Alliant Energy's Form 10-K for the year 2022 (File No .

10.4# IES Industries Inc.

Amended and Restated Key Employee Deferred Compensation Agreement, as amended (incorporated by reference to Exhibit 10.7 to Alliant Energy’s Form 10-K for the year 2015 (File No.

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Exhibit Number Description

10.5# Alliant Energy Rabbi Trust Agreement for DCPs (incorporated by reference to Exhibit 10.19 to Alliant Energy’s Form 10-K for the year 2005 (File No.

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Larsen (incorporated by reference to Exhibit 10.3 to Alliant Energy’s Form 8-K, filed December 12, 2008 (File No.

10.9# Alliant Energy Defined Contribution SRP (incorporated by reference to Exhibit 10.1 to Alliant Energy’s Form 10-Q for the quarter ended September 30, 2010 (File No.

10.9a# Amendment to the Alliant Energy Defined Contribution SRP (incorporated by reference to Exhibit 10.3 to Alliant Energy’s Form 8-K, filed December 5, 2011 (File No.

10.9b# Amendment to the Alliant Energy Defined Contribution SRP (incorporated by reference to Exhibit 10.1 to Alliant Energy’s Form 8-K, filed March 12, 2014 (File No.

10.10# Form of Key Executive Employment and Severance Agreement (KEESA), by and between Alliant Energy and J.O.

Larsen (incorporated by reference to Exhibit 10.1 to Alliant Energy’s Form 8-K, filed October 28, 2021 (File No.

10.8# Form of Key Executive Employment and Severance Agreement (KEESA), by and between Alliant Energy and eac h of J.O.

Larsen and L.M.

Barton (incorporated by reference to Exhibit 10.1 to Alliant Energy’s Form 8-K, filed October 28, 2021 (File No.

10.9# Form of KEESA, by and between Alliant Energy and each of R.J.

de Leon , T.L.

Kouba and M .

Luhrs (incorporated by reference to Exhibit 10.2 to Alliant Energy’s Form 8-K, filed October 28, 2021 (File No.

Kouba and R .

Sundararajan (incorporated by reference to Exhibit 10.2 to Alliant Energy’s Form 8-K, filed October 28, 2021 (File No.

10.10# Executive Officer Severance Benefit Plan, as amended and restated, effective October 29, 2018 (incorporated by reference to Exhibit 10.1 to Alliant Energy’s Form 10-Q for the quarter ended September 30, 2018 (File No.

10.13# Terms of Alliant Energy Executive Performance Pay Plan (incorporated by reference to Exhibit 10.18 to Alliant Energy’s Form 10-K for the year 2015 (File No.

10.14# Form of Sign-On Bonus Reimbursement Agreement

10.11# Terms of Alliant Energy Executive Sho rt-term Incentive Plan

10.12# Form of Sign-On Bonus Reimbursement Agreement (incorporated by reference to Exhibit 10.14 to Alliant Energy's Form 10-K for the year 2022 (File No .

10.13# Form of Relocation Reimbursement Agreement

12 unchanged sentences

32.2 Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for IPL

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Exhibit Number Description

32.3 Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for WPL

97 Alliant Energy Incentive Compensation Re covery Policy

101.INS Inline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document

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FORM 10-K SUMMARY

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Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrants have duly caused this report to be signed on their behalf by the undersigned, thereunto duly authorized on the 16th day of February 2024.

1 unchanged sentence

CORPORATION AND LIGHT COMPANY AND LIGHT COMPANY

Larsen John O.

Chair, President and Chief Executive Officer Chair and Chief Executive Officer Chair and Chief Executive Officer

Barton Lisa M.

President and Chief Executive Officer Chief Executive Officer Chief Executive Officer

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the Registrants and in the capacities indicated on the 16th day of February 2024.

1 unchanged sentence

CORPORATION AND LIGHT COMPANY AND LIGHT COMPANY

Larsen /s/ John O.

Larsen John O.

Chair, President, Chief Executive Officer and Director (Principal Executive Officer) Chair, Chief Executive Officer and Director (Principal Executive Officer) Chair, Chief Executive Officer and Director (Principal Executive Officer)

Barton Lisa M.

President, Chief Executive Officer and Director (Principal Executive Officer) Chief Executive Officer and Director (Principal Executive Officer) Chief Executive Officer and Director (Principal Executive Officer)

/s/ Robert J.

Durian /s/ Robert J.

/s/ Robert J.

Durian Robert J.

2 unchanged sentences

/s/ Benjamin M.

Bilitz /s/ Benjamin M.

/s/ Benjamin M.

Bilitz Benjamin M.

1 unchanged sentence

Chief Accounting Officer and Controller (Principal Accounting Officer) Chief Accounting Officer and Controller (Principal Accounting Officer) Chief Accounting Officer and Controller (Principal Accounting Officer)

Larsen, Executive Chairman, Chairman of the Board and Director John O.

Larsen, Executive Chairman, Chairman of the Board and Director

/s/ Patrick E.

Allen /s/ Patrick E.

Allen, Director Patrick E.

/s/ Patrick E.

Allen, Director

/s/ Ignacio A.

Cortina, Director

/s/ Stephanie L.

Cox /s/ Stephanie L.

Cox, Director Stephanie L.

/s/ Stephanie L.

Cox, Director

Joy Falotico /s/ N.

Joy Falotico, Director N.

Cox, Director

Joy Falotico, Director

/s/ Michael D.

Garcia /s/ Michael D.

Garcia, Director Michael D.

/s/ Michael D.

Garcia, Director

/s/ Singleton B.

McAllister /s/ Singleton B.

McAllister, Director Singleton B.

McAllister, Director

Newport /s/ Roger K.

Newport, Director Roger K.

Garcia, Director

Newport, Director

/s/ Thomas F.

O’Toole /s/ Thomas F.

O’Toole, Director Thomas F.

/s/ Thomas F.

O’Toole, Director

Sanders /s/ Carol P.

Sanders, Director Carol P.

O’Toole, Director

Sanders, Director

Whiting /s/ Susan D.

Whiting, Director Susan D.

Whiting, Director

Sanders, Director

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 9A. Controls and Procedures