What changed in this filing

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Item 9A. Controls and Procedures

2022-02-16 compared with 2021-02-19 · 91 added, 159 removed, 245 unchanged (51% of the section changed)

15 unchanged sentences

Attestation Report of Independent Registered Public Accounting Firm .

The attestation report of Deloitte & Touche LLP, the Company’s independent registered public accounting firm, regarding the Company’s internal control over financial reporting is provided in Item 8 of this Form 10-K.

OTHER INFORMATION

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DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

Not applicable.

DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

3 unchanged sentences

The information required by this Item regarding the Audit Committee and the Company’s Audit Committee financial experts is incorporated by reference to the information under “Committees of the Board of Directors – Audit Committee” in the Company’s definitive Proxy Statement for the 2022 Annual Meeting.

The Company has adopted a code of conduct that applies to all of its directors, officers (including its principal executive officer, principal financial officer, and its principal accounting officer or controller or person performing similar functions) and employees.

The Company’s code of conduct is available on its website at www.ottertail.com.

The Company intends to satisfy the disclosure requirements under Item 5.05 of Form 8-K regarding an amendment to, or waiver from, a provision of its code of conduct by posting such information on its website at the address specified above.

The Company has adopted a code of business ethics that applies to all of its directors, officers (including its principal executive officer, principal financial officer, and its principal accounting officer or controller or person performing similar functions) and employees.

The Company’s code of business ethics is available on its website at www.ottertail.com.

The Company intends to satisfy the disclosure requirements under Item 5.05 of Form 8-K regarding an amendment to, or waiver from, a provision of its code of business ethics by posting such information on its website at the address specified above.

Information on the Company’s website is not deemed to be incorporated by reference into this report on Form 10-K.

EXECUTIVE COMPENSATION

The information required by this Item is incorporated by reference to the information under “Compensation Discussion and Analysis,” “Report of Compensation Committee,” “Executive Compensation,” “Pay Ratio Disclosure” and “Director Compensation” in the Company's definitive Proxy Statement for the 2021 Annual Meeting.

The information required by this Item is incorporated by reference to the information under “Compensation Discussion and Analysis,” “Report of Compensation and Human Capital Management Committee,” “Executive Compensation,” “Pay Ratio Disclosure” and “Director Compensation” in the Company's definitive Proxy Statement for the 2022 Annual Meeting.

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS

15 unchanged sentences

2014 Stock Incentive Plan 387,313 (1) $ 0.00 722,200 (2)

1999 Stock Incentive Plan 541 (3) $ 0.00 — (4)

1999 Employee Stock Purchase Plan — N/A 290,127 (3)

1 unchanged sentence

Total 387,313 — 1,012,327

(1) Includes 82,500, 83,400, and 59,477 performance-based share awards granted in 2020, 2019 and 2018, respectively, 90,885 restricted stock units outstanding as of December 31, 2020, and 718 stock units as part of the director deferred compensation program and excludes 37,776 shares of restricted stock issued under the 2014 Stock Incentive Plan.

(1) Includes 118,500, 82,500 and 83,400 performance-based share awards, assuming a maximum payout, granted in 2021, 2020 and 2019, respectively, 102,265 restricted stock units outstanding as of December 31, 2021, and 648 stock units outstanding as part of the director deferred compensation program and excludes 35,828 shares of restricted stock issued to members of the board of directors.

(2) The 2014 Stock Incentive Plan provides for the issuance of any shares available under the plan in the form of restricted stock, restricted stock units, performance awards and other types of stock-based awards, in addition to the granting of options, warrants or stock appreciation rights.

(3) Director deferred compensation program stock units under the 1999 Stock Incentive Plan.

(4) The 1999 Stock Incentive Plan provided for the issuance of any shares available under the plan in the form of restricted stock, restricted stock units, performance awards and other types of stock-based awards, in addition to the granting of options, warrants or stock appreciation rights.

The 1999 Stock Incentive Plan expired by its terms on December 13, 2013 and no more awards may be granted thereunder.

(3) Shares to be issued based on employee’s election to participate in the plan.

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CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE

2 unchanged sentences

The information required by this Item is incorporated by reference to the information under “Ratification of Independent Registered Public Accounting Firm – Fees” and “Ratification of Independent Registered Public Accounting Firm – Pre-Approval of Audit/Non-Audit Services Policy” in the Company’s definitive Proxy Statement for the 2022 Annual Meeting.

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EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

10 unchanged sentences

Schedule II - Valuation and Qualifying Accounts and Reserves

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SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT

7 unchanged sentences

Interest Receivable from Subsidiaries 117 117

Notes Receivable from Subsidiaries 6,767 —

Other 1,410 1,063

17 unchanged sentences

Long-Term Debt, Net of Current Maturities 79,746 79,695

Common Shareholder Equity 870,966 781,482

Common Stockholders' Equity 990,777 870,966

Total Capitalization 1,070,523 950,661

1 unchanged sentence

See accompanying notes to condensed financial statements.

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OTTER TAIL CORPORATION (PARENT COMPANY)

12 unchanged sentences

Income Before Income Taxes 171,839 90,663 81,365

Income Tax (Benefit) Expense ( 5,188 ) ( 5,482 ) ( 3,278 )

Income Tax Benefit 4,930 5,188 5,482

Net Income $ 176,769 $ 95,851 $ 86,847

See accompanying notes to condensed financial statements.

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OTTER TAIL CORPORATION (PARENT COMPANY)

8 unchanged sentences

Cash Used in Investing Activities ( 884 ) ( 2,419 ) ( 257 )

Net Cash (Used in) Provided by Investing Activities ( 152,237 ) ( 33,909 ) ( 24,613 )

Net Cash Used in Investing Activities ( 715 ) ( 152,237 ) ( 33,909 )

Cash Flows from Financing Activities

Change in Checks Written in Excess of Cash 125 ( 31 ) 31

Net Short-Term (Repayments) Borrowings 59,166 ( 3,215 ) 9,215

Borrowings from (Repayments to) Subsidiaries 44,741 28,985 ( 1,281 )

Net (Repayments) Borrowings on Short-Term Debt ( 42,529 ) 59,166 ( 3,215 )

Borrowings from Subsidiaries 49,085 44,741 28,985

Proceeds from Issuance of Common Stock 696 52,432 20,338

Common Stock Issuance Expenses ( 648 ) ( 577 ) ( 108 )

Payments for Retirement of Capital Stock ( 2,069 ) ( 2,730 ) ( 3,011 )

Short-Term and Long-Term Debt Issuance Expenses — ( 270 ) ( 164 )

Payments for Shares Withheld for Employee Tax Obligations ( 1,507 ) ( 2,069 ) ( 2,730 )

Payments for Retirement of Long-Term Debt ( 169 ) ( 182 ) ( 172 )

Dividends Paid ( 64,864 ) ( 60,314 ) ( 55,723 )

Net Cash Used in Financing Activities 93,251 ( 13,395 ) ( 48,705 )

Other, net ( 689 ) ( 523 ) ( 878 )

Net Cash Used in (Provided by) Financing Activities ( 59,977 ) 93,251 ( 13,395 )

Net Change in Cash and Cash Equivalents 3 ( 4,959 ) 4,959

2 unchanged sentences

See accompanying notes to condensed financial statements.

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OTTER TAIL CORPORATION (PARENT COMPANY)

1 unchanged sentence

Incorporated by Reference

Otter Tail Corporation’s consolidated statements of comprehensive income and common shareholders’ equity in Part II, Item 8 are incorporated by reference.

OTC’s consolidated statements of comprehensive income and common shareholders’ equity in Part II, Item 8 are incorporated by reference.

Basis of Presentation

The condensed financial information of Otter Tail Corporation is presented to comply with Rule 12-04 of Regulation S-X.

The condensed financial information of OTC is presented to comply with Rule 12-04 of Regulation S-X.

The unconsolidated condensed financial statements do not reflect all of the information and notes normally included with financial statements prepared in accordance with GAAP.

Therefore, these condensed financial statements should be read with the consolidated financial statements and related notes included in this report on Form 10-K.

Otter Tail Corporation’s investments in subsidiaries are presented under the equity method of accounting.

OTC’s investments in subsidiaries are presented under the equity method of accounting.

Under this method, the assets and liabilities of subsidiaries are not consolidated.

33 unchanged sentences

$ 2,734 $ 117 $ — $ 79,069 $ 7 $ 134,352

Dividends paid to Otter Tail Corporation (the Parent) from its subsidiaries were as follows:

Dividends paid to OTC (the Parent) from its subsidiaries were as follows:

(in thousands) 2021 2020 2019

Cash Dividends Paid to Parent by Subsidiaries $ 64,790 $ 55,614 $ 55,660

See Otter Tail Corporation’s notes to consolidated financial statements in Part II, Item 8 for other disclosures.

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See OTC’s notes to consolidated financial statements in Part II, Item 8 for other disclosures.

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS AND RESERVES

12 unchanged sentences

1 Amounts under Allowance for Credit Losses reflect deductions to the allowance for amounts written-off, net of recoveries.

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2 Amounts under Deferred Tax Asset Valuation Allowance reflect a release of a valuation allowance based on current expectations of the realizability of the associated deferred tax asset.

The following Exhibits are filed as part of, or incorporated by reference into, this report.

2-A —Asset Purchase Agreement, dated as of November 16, 2016, among Otter Tail Power Company, EDF Renewable Development, Inc., Power Partners Midwest, LLC, EDF-RE US Development, LLC and Merricourt Power Partners, LLC.**/***

2-B —Turnkey Engineering, Procurement and Construction Services Agreement, dated as of November 16, 2016, between Otter Tail Power Company and EDF-RE US Development, LLC.**/***

2-C —First Amendment to Asset Purchase Agreement and Turnkey Engineering, Procurement and Construction Services Agreement dated June 11, 2019, with EDF Renewables Development, Inc., f/k/a, EDF Renewable Development, Inc., Power Partners Midwest, LLC, EDF-RE US Development, LLC and Merricourt Power Partners, LLC.***

3-A —Restated Articles of Incorporation.

3-B —Restated Bylaws.

4-A —Note Purchase Agreement, dated as of August 20, 2007, between Otter Tail Power Company and the Purchasers named therein.

4-A-1 —First Amendment, dated as of December 14, 2007, to Note Purchase Agreement, dated as of August 20, 2007, between Otter Tail Power Company and the Purchasers named therein.

4-A-2 —Second Amendment, dated as of September 11, 2008, to Note Purchase Agreement, dated as of August 20, 2007, between Otter Tail Power Company and the Purchasers named therein.

4-A-3 —Third Amendment, dated as of June 26, 2009, to Note Purchase Agreement dated as of August 20, 2007, between Otter Tail Power Company and the Purchasers named therein.

4-B —Third Amended and Restated Credit Agreement dated as of October 29, 2012 among Otter Tail Corporation, the Banks named therein, Bank of America, N.A.

and JPMorgan Chase Bank, N.A., as Co-Syndication Agents, KeyBank National Association, as Documentation Agent, U.S.

Bank National Association, as administration agent for the Banks and U.S.

Bank National Association, Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P.

Morgan Securities LLC, as Joint Lead Arrangers and Joint Book Runners.

4-B-1 —First Amendment to Third Amended and Restated Credit Agreement, dated as of October 29, 2013, among Otter Tail Corporation, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

and JPMorgan Chase Bank, N.A., each as a Co-Syndication Agent and as a Bank, KeyBank National Association, as Documentation Agent and as a Bank, and Bank of the West and Union Bank, N.A., as Banks.

4-B-2 —Second Amendment to Third Amended and Restated Credit Agreement, dated as of November 3, 2014, among Otter Tail Corporation, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

and JPMorgan Chase Bank, N.A., each as a Co-Syndication Agent and as a Bank, KeyBank National Association, as Documentation Agent and as a Bank, and Bank of the West as a Bank.

4-B-3 —Third Amendment to Third Amended and Restated Credit Agreement, dated as of October 29, 2015, among Otter Tail Corporation, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

and JPMorgan Chase Bank, N.A., each as a Co-Syndication Agent and as a Bank, KeyBank National Association, as Documentation Agent and as a Bank, and Bank of the West as a Bank.

4-B-4 —Fourth Amendment to Third Amended and Restated Credit Agreement, dated as of October 31, 2016, among Otter Tail Corporation, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

and JPMorgan Chase Bank, N.A., each as a Co-Syndication Agent and as a Bank, KeyBank National Association, as Documentation Agent and as a Bank, and Bank of the West as a Bank.

4-B-5 —Fifth Amendment to Third Amended and Restated Credit Agreement, dated as of October 31, 2017, among Otter Tail Corporation, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

and JPMorgan Chase Bank, N.A., each as a Co-Syndication Agent and as a Bank, KeyBank National Association, as Documentation Agent and as a Bank, and Bank of the West as a Bank.

4-B-6 —Sixth Amendment to Third Amended and Restated Credit Agreement, dated as of October 31, 2018, among Otter Tail Corporation, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

and JPMorgan Chase Bank, N.A., each as a Co-Syndication Agent and as a Bank, KeyBank National Association, as Documentation Agent and as a Bank, and Bank of the West as a Bank.

4-B-7 —Seventh Amendment to Third Amended and Restated Credit Agreement, dated as of October 31, 2019, among Otter Tail Corporation, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

and JPMorgan Chase Bank, N.A., each as a Co-Syndication Agent and as a Bank, KeyBank National Association, as Documentation Agent and as a Bank, and Wells Fargo Bank, National Association, as a Bank.

4-C —Second Amended and Restated Credit Agreement dated as of October 29, 2012 among Otter Tail Power Company, the Banks named therein, JPMorgan Chase Bank, N.A.

and Bank of America, N.A., as Co-Syndication Agents, KeyBank National Association and CoBank, ACB, as Co-Documentation Agents, U.S.

Bank National Association, as administrative agent for the Banks, and U.S.

Bank National Association, Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P.

Morgan Securities LLC, as Joint Lead Arrangers and Joint Book Runners.

4-C-1 —First Amendment to Second Amended and Restated Credit Agreement, dated as of October 29, 2013, among Otter Tail Power Company, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

and JPMorgan Chase Bank, N.A., each as a Co-Syndication Agent and as a Bank, KeyBank National Association, as Documentation Agent and as a Bank, CoBank, ACB, as a Co-Documentation Agent and as a Bank, and Wells Fargo Bank, National Association and Union Bank, N.A., as Banks.

4-C-2 —Second Amendment to Second Amended and Restated Credit Agreement, dated as of November 3, 2014, among Otter Tail Power Company, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

4-C-3 —Third Amendment to Second Amended and Restated Credit Agreement, dated as of October 29, 2015, among Otter Tail Power Company, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

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4-C-4 —Fourth Amendment to Second Amended and Restated Credit Agreement, dated as of October 31, 2016, among Otter Tail Power Company, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

4-C-5 —Fifth Amendment to Second Amended and Restated Credit Agreement, dated as of October 31, 2017, among Otter Tail Power Company, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

4-C-6 —Sixth Amendment to Second Amended and Restated Credit Agreement, dated as of October 31, 2018, among Otter Tail Power Company, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

4-C-7 —Seventh Amendment to Second Amended and Restated Credit Agreement, dated as of October 31, 2019, among Otter Tail Power Company, U.S.

Bank National Association, as Administrative Agent and as a Bank, Bank of America, N.A.

4-D —Note Purchase Agreement, dated as of July 29, 2011, between Otter Tail Power Company and the Purchasers named therein.

4-E —Note Purchase Agreement dated as of August 14, 2013 between Otter Tail Power Company and the Purchasers named therein.

4-F —Note Purchase Agreement dated as of September 23, 2016 between Otter Tail Corporation and the Purchasers named therein.

4-G —Note Purchase Agreement dated as of November 14, 2017 between Otter Tail Power Company and the Purchasers named therein.

4-H —Note Purchase Agreement dated as of September 12, 2019 between Otter Tail Power Company and the Purchasers named therein.

4-I —Description of Securities

10-A —Agreement for Sharing Ownership of Generating Plant by and between the Company, Montana-Dakota Utilities Co., and Northwestern Public Service Company (dated as of January 7, 1970).

3.1 Third Restated Articles of Incorporation , dated April 12, 2021 .

3.2 Restated Bylaws , dated April 12, 2021 .

4.1 Description of Securities

10.1.0 Note Purchase Agreement, dated as of August 20, 2007, between Otter Tail Power Company and the Purchasers named therein.

10.1.1 First Amendment, dated as of December 14, 2007, to Note Purchase Agreement, dated as of August 20, 2007, between Otter Tail Power Company and the Purchasers named therein.

10.1.2 Second Amendment, dated as of September 11, 2008, to Note Purchase Agreement, dated as of August 20, 2007, between Otter Tail Power Company and the Purchasers named therein.

10.1.3 Third Amendment, dated as of June 26, 2009, to Note Purchase Agreement dated as of August 20, 2007, between Otter Tail Power Company and the Purchasers named therein.

10.2 Note Purchase Agreement dated as of August 14, 2013 between Otter Tail Power Company and the Purchasers named therein.

10.3 Note Purchase Agreement dated as of September 23, 2016 between Otter Tail Corporation and the Purchasers named therein.

10.4 Note Purchase Agreement dated as of November 14, 2017 between Otter Tail Power Company and the Purchasers named therein.

10.5 Note Purchase Agreement dated as of September 12, 2019 between Otter Tail Power Company and the Purchasers named therein.

10.6 Note Purchase Agreement date d as of June 10, 2021 be tween Otter Tail Power Company and the Purchasers named therein.

10.7 Fourth Amended and Restated Credit Agreement, dated as of September 30, 2021, by and between Otter Tail Corporation, as Borrower, and the banks named therein, with U.S.

Bank National Association, as Administrative Agent.

10.8 Third Amended and Restated Credit Agreement, dated as of September 30, 2021, by and between Otter Tail Power Company, as Borrower, and the banks named therein, with U.S.

Bank Nation Association, as Administration Agent.

10.9.0 Agreement for Sharing Ownership of Generating Plant by and between the Company, Montana-Dakota Utilities Co., and Northwestern Public Service Company (dated as of January 7, 1970).

Previously filed as Exhibit 10-F in Form 10-K for the year ended December 31, 1989.

10-A-1 —Letter of Intent for purchase of share of Big Stone Plant from Northwestern Public Service Company (dated as of May 8, 1984).

10.9.1 Letter of Intent for purchase of share of Big Stone Plant from Northwestern Public Service Company (dated as of May 8, 1984).

Previously filed as Exhibit 10-F-1 in Form 10-K for the year ended December 31, 1989.

10-A-2 —Supplemental Agreement No.

10.9.2 Supplemental Agreement No.

1 to Agreement for Sharing Ownership of Big Stone Plant (dated as of July 1, 1983).

Previously filed as Exhibit 10-F-2 in Form 10-K for the year ended December 31, 1991.

10-A-3 —Supplemental Agreement No.

10.9.3 Supplemental Agreement No.

2 to Agreement for Sharing Ownership of Big Stone Plant (dated as of March 1, 1985).

Previously filed as Exhibit 10-F-3 in Form 10-K for the year ended December 31, 1991.

10-A-4 —Supplemental Agreement No.

10.9.4 Supplemental Agreement No.

3 to Agreement for Sharing Ownership of Big Stone Plant (dated as of March 31, 1986).

Previously filed as Exhibit 10-F-4 in Form 10-K for the year ended December 31, 1991.

10-A-5 —Supplemental Agreement No.

10.9.5 Supplemental Agreement No.

4 to Agreement for Sharing Ownership of Big Stone Plant (dated as of April 24, 2003).

10-A-6 —Amendment I to Letter of Intent dated May 8, 1984, for purchase of share of Big Stone Plant.

10.9.6 Amendment I to Letter of Intent dated May 8, 1984, for purchase of share of Big Stone Plant.

Previously filed as Exhibit 10-F-5 in Form 10-K for the year ended December 31, 1992.

10-B —Big Stone South–Ellendale Project Ownership Agreement dated as of June 12, 2015 between Otter Tail Power Company, a wholly owned subsidiary of Otter Tail Corporation, and Montana-Dakota Utilities Co., a division of MDU Resources Group, Inc.**

10-C —Agreement for Sharing Ownership of Coyote Station Generating Unit No.

10.10 Big Stone South–Ellendale Project Ownership Agreement dated as of June 12, 2015 between Otter Tail Power Company, a wholly owned subsidiary of Otter Tail Corporation, and Montana-Dakota Utilities Co., a division of MDU Resources Group, Inc.**

10.11.0 Agreement for Sharing Ownership of Coyote Station Generating Unit No.

1 by and between the Company, Minnkota Power Cooperative, Inc., Montana-Dakota Utilities Co., Northwestern Public Service Company and Minnesota Power & Light Company (dated as of July 1, 1977).

Previously filed as Exhibit 5-H in filing 2-61043.

10-C-1 —Supplemental Agreement No.

10.11.1 Supplemental Agreement No.

One, dated as of November 30, 1978, to Agreement for Sharing Ownership of Coyote Generating Unit No.

Previously filed as Exhibit 10-H-1 in Form 10-K for the year ended December 31, 1989.

10-C-2 —Supplemental Agreement No.

10.11.2 Supplemental Agreement No.

Two, dated as of March 1, 1981, to Agreement for Sharing Ownership of Coyote Generating Unit No.

2 unchanged sentences

Previously filed as Exhibit 10-H-2 in Form 10-K for the year ended December 31, 1989.

10-C-3 —Amendment, dated as of July 29, 1983, to Agreement for Sharing Ownership of Coyote Generating Unit No.

10.11.3 Amendment, dated as of July 29, 1983, to Agreement for Sharing Ownership of Coyote Generating Unit No.

Previously filed as Exhibit 10-H-3 in Form 10-K for the year ended December 31, 1989.

10-C-4 —Agreement, dated as of September 5, 1985, containing Amendment No.

10.11.4 Agreement, dated as of September 5, 1985, containing Amendment No.

3 to Agreement for Sharing Ownership of Coyote Generating Unit No.

2 unchanged sentences

Previously filed as Exhibit 10-H-4 in Form 10-K for the year ended December 31, 1992.

10-C-5 —Amendment, dated as of June 14, 2001, to Agreement for Sharing Ownership of Coyote Generating Unit No.

10-C-6 —Amendment, dated as of April 24, 2003, to Agreement for Sharing Ownership of Coyote Generating Unit No.

10-D —Lignite Sales Agreement between Coyote Creek Mining Company, L.L.C.

10.11.5 Amendment, dated as of June 14, 2001, to Agreement for Sharing Ownership of Coyote Generating Unit No.

10.11.6 Amendment, dated as of April 24, 2003, to Agreement for Sharing Ownership of Coyote Generating Unit No.

10.12.0 Lignite Sales Agreement between Coyote Creek Mining Company, L.L.C.

and Otter Tail Power Company, Northern Municipal Power Agency, Montana-Dakota Utilities Co., Northwestern Corporation, dated as of October 10, 2012.**

10-D-1 —First Amendment to Lignite Sales Agreement dated as of January 30, 2014 among Otter Tail Power Company, Northern Municipal Power Agency, Montana-Dakota Utilities Co., a division of MDU Resources Group, Inc., NorthWestern Corporation and Coyote Creek Mining Company, L.L.C.

10-D-2 —Second Amendment to Lignite Sales Agreement dated as of March 16, 2015 among Otter Tail Power Company, Northern Municipal Power Agency, Montana-Dakota Utilities Co., a division of MDU Resources Group, Inc., NorthWestern Corporation and Coyote Creek Mining Company, L.L.C.

10-E —Wind Energy Purchase Agreement dated May 9, 2013 between Otter Tail Power Company and Ashtabula Wind III, LLC.**

10-F-1 —Deferred Compensation Plan for Directors, as amended.*

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10-F-1a —First Amendment of Deferred Compensation Plan for Directors (2003 Restatement), as amended.*

10-F-1b —Second Amendment of Deferred Compensation Plan for Directors (2003 Restatement), as amended.*

10-F-2 —Executive Survivor and Supplemental Retirement Plan (2020 Restatement).*

10-F-3 —Nonqualified Retirement Plan (2011 Restatement).*

10-F-4 —1999 Employee Stock Purchase Plan, As Amended (2016).

10-F-5 —1999 Stock Incentive Plan, As Amended (2006).*

10-F-6 —2014 Executive Annual Incentive Plan.*

10-F-7 —Otter Tail Corporation 2014 Stock Incentive Plan.*

10-F-8 —Summary of Non-Employee Director Compensation (2016).*

10-F-9 —Form of Restricted Stock Unit Award Agreement (Executives).*

10-F-10 —Form of Restricted Stock Unit Award Agreement (Legacy).*

10-F-11 —Form of Restricted Stock Award Agreement for Directors.*

10-F-12 —Otter Tail Corporation Executive Restoration Plus Plan, as Amended and Restated.*

10-F-12a —First Amendment of Otter Tail Corporation Executive Restoration Plus Plan.*

10-F-12b —Second Amendment of Otter Tail Corporation Executive Restoration Plus Plan.*

10-F-13 —Summary of Non-Employee Director Compensation (2018).*

10-F-14 —Form of 2018 Performance Award Agreement (Executives).*

10-F-15 —Form of 2018 Performance Award Agreement (Legacy).*

10-F-16 —Form of 2018 Restricted Stock Award Agreement for Directors.*

10-F-17 —Summary of Non-Employee Director Compensation (2019).*

10-G —Distribution Agreement dated November 8, 2019, between Otter Tail Corporation and KeyBanc Capital Markets Inc.

10-H —Executive Employment Agreement, Kevin Moug.*

10-I-1 —Change in Control Severance Agreement, Kevin G.

10-I-2 —Change in Control Severance Agreement, Chuck MacFarlane.*

10-I-3 —Change in Control Severance Agreement, Timothy Rogelstad.*

10-I-4 —Change in Control Severance Agreement, Paul Knutson.*

10-I-5 —Change in Control Severance Agreement, John Abbott.*

10-I-6 —Change in Control Severance Agreement, Jennifer Smestad.*

10-J —Otter Tail Corporation Executive Severance Plan.*

21-A —Subsidiaries of Registrant.

23-A —Consent of Deloitte & Touche LLP.

24-A —Power of Attorney.

10.12.1 First Amendment to Lignite Sales Agreement dated as of January 30, 2014 among Otter Tail Power Company, Northern Municipal Power Agency, Montana-Dakota Utilities Co., a division of MDU Resources Group, Inc., NorthWestern Corporation and Coyote Creek Mining Company, L.L.C.

10.12.2 Second Amendment to Lignite Sales Agreement dated as of March 16, 2015 among Otter Tail Power Company, Northern Municipal Power Agency, Montana-Dakota Utilities Co., a division of MDU Resources Group, Inc., NorthWestern Corporation and Coyote Creek Mining Company, L.L.C.

10.13 Wind Energy Purchase Agreement dated May 9, 2013 between Otter Tail Power Company and Ashtabula Wind III, LLC.**

10.14.0 Deferred Compensation Plan for Directors (2003 R estatement) .*

10.14.1 First Amendment of Deferred Compensation Plan for Directors (2003 Restatement), as A mended.*

10.14.2 Second Amendment of Deferred Compensation Plan for Directors (2003 Restatement), as A mended.*

10.15 Executive Survivor and Supplemental Retirement Plan (2020 Restatement).*

10.16 Nonqualified Retirement Plan (2011 Restatement).*

10.17 1999 Employee Stock Purchase Plan, As Amended (2016).

10.18 1999 Stock Incentive Plan, As Amended (2006).*

10.19 2014 Executive Annual Incentive Plan.*

10.20 Otter Tail Corporation 2014 Stock Incentive Plan.*

10.21 Summary of Non-Employee Director Compensation (2016).*

10.21 Form of 2015 Restricted Stock Unit Award Agreement (Executives).*

10.22 Form of 2015 Restricted Stock Unit Award Agreement (Legacy).*

10.23 Form of 2015 Restricted Stock Award Agreement for Directors.*

10.24 Otter Tail Corporation Executive Restoration Plus Plan, 2020 Restatement .*

10.25 Summary of Non-Employee Director Compensation (2018).*

10.26 Form of 2018 Performance Award Agreement (Executives).*

10.27 Form of 2018 Performance Award Agreement (Legacy).*

10.28 Form of 2018 Restricted Stock Award Agreement for Directors.*

10.29 Summary of Non-Employee Director Compensation (2019).*

10.30 Executive Employment Agreement, Kevin Moug , as Amended [effective January 1, 2013] .*

10.31 Change in Control Severance Agreement, Kevin G.

Moug , dated July 1, 2009 .*

10.32 Change in Control Severance Agreement, Chuck MacFarlane , dated February 24, 2012 .*

10.33 Change in Control Severance Agreement, Timothy Rogelstad , dated April 14, 2014 .*

10.34 Change in Control Severance Agreement, Paul Knutson , dated December 17, 2012 .*

10.35 Change in Control Severance Agreement, John Abbott , dated April 1 3, 2015 .*

10.36 Change in Control Severance Agreement, Jennifer Smestad , dated January 1, 2018 .*

10.37 Otter Tail Corporation Executive Severance Plan (2015) .*

21 Subsidiaries of Registrant.

23 Consent of Deloitte & Touche LLP.

24 Power of Attorney.

31.1 Certification of Chief Executive Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

10 unchanged sentences

**Confidential information has been omitted from this Exhibit and filed separately with the Securities and Exchange Commission pursuant to a confidential treatment request under Rule 24b-2.

***Certain information has been omitted pursuant to Item 601(b)(2) of Regulation S-K.

The Company hereby undertakes to furnish copies of any of the omitted schedules and exhibits to the Securities and Exchange Commission upon request.

Pursuant to Item 601(b)(4)(iii) of Regulation S-K, copies of certain instruments defining the rights of holders of certain long-term debt of the Company are not filed, and in lieu thereof, the Company agrees to furnish copies thereof to the Securities and Exchange Commission upon request.

Table of Content s

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 registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

12 unchanged sentences

Chairman of the Board and Director ) Pro Se and Attorney-in-Fact

) Dated February 19, 2021

February 16, 2022

Bohn, Director )

5 unchanged sentences

Webb, Director )

LeBeau, 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