How are indirect OTTR share holdings structured for the CEO?

In addition to direct holdings, the CEO has indirect Otter Tail ownership through two vehicles: 75,459 common shares held by a Spousal Lifetime Access Trust and 3,051 common shares held through an employee stock ownership plan, as disclosed in the Form 4 holdings table.

Otter Tail (OTTR) CEO details RSU vesting and tax-share withholding

Filing Impact

(High)

Filing Sentiment

(Negative)

Form Type

Rhea-AI Filing Summary

Otter Tail Corporation’s President & CEO Charles S. MacFarlane reported routine equity award activity. On February 6, 2026, restricted stock units converted into 9,125 shares of common stock, reflecting vesting of prior grants.

To cover withholding taxes on this vesting, the company retained 4,277 shares at a price of $87.83 per share, as indicated by transaction code "F". Following these transactions, MacFarlane directly held 227,412 common shares, with additional indirect holdings of 75,459 shares through a Spousal Lifetime Access Trust and 3,051 shares via an ESOP.

Insider Trade Summary

9,125 shares exercised/converted

Mixed 8 txns

Insider MACFARLANE CHARLES S

Role President & CEO

Type	Security	Shares	Price	Value
Exercise	Restricted Stock Units	2,175	$0.00	--
Exercise	Restricted Stock Units	2,500	$0.00	--
Exercise	Restricted Stock Units	1,975	$0.00	--
Exercise	Restricted Stock Units	2,475	$0.00	--
Exercise	Common Stock	9,125	$0.00	--
Tax Withholding	Common Stock	4,277	$87.83	$376K
holding	Common Stock	--	--	--
holding	Common Stock	--	--	--

Holdings After Transaction: Restricted Stock Units — 0 shares (Direct); Common Stock — 231,689 shares (Direct); Common Stock — 75,459 shares (Indirect, by Spousal Lifetime Access Trust)

Footnotes (1)

Each restricted stock unit represents a contingent right to receive one share of Otter Tail Corporation stock. These shares were withheld by the Corporation to pay taxes due upon vesting of this award, exempt pursuant to Rule 16b-3(e). Total direct holdings include shares acquired through the Dividend Reinvestment Plan, the Employee Stock Purchase Plan and shares acquired pursuant to Stock Options, Restricted Stock Awards, Restricted Stock Units and Performance Share Awards. The restricted stock units vest in four equal annual installments beginning the date shown above.

Form 4 Insider Transactions: What Each Field Means →

02/09/2026 - 05:05 PM

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

MACFARLANE CHARLES S

(Last)

(First)

(Middle)

215 SOUTH CASCADE STREET

(Street)

FERGUS FALLS

56537

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
Otter Tail Corp [ OTTR ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	President & CEO

3. Date of Earliest Transaction (Month/Day/Year)
02/06/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	02/06/2026		M		9,125	A	⁽¹⁾	231,689	D
Common Stock	02/06/2026		F		4,277⁽²⁾	D	$87.83	227,412⁽³⁾	D
Common Stock								75,459	I	by Spousal Lifetime Access Trust
Common Stock								3,051	I	by ESOP

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Restricted Stock Units	⁽¹⁾	02/06/2026		M			2,175	02/06/2023⁽⁴⁾	⁽⁴⁾	Common Stock	0	$0	0	D
Restricted Stock Units	⁽¹⁾	02/06/2026		M			2,500	02/06/2024⁽⁴⁾	⁽⁴⁾	Common Stock	2,500	$0	2,500	D
Restricted Stock Units	⁽¹⁾	02/06/2026		M			1,975	02/06/2025⁽⁴⁾	⁽⁴⁾	Common Stock	3,950	$0	3,950	D
Restricted Stock Units	⁽¹⁾	02/06/2026		M			2,475	02/06/2026⁽⁴⁾	⁽⁴⁾	Common Stock	7,425	$0	7,425	D

Explanation of Responses:

1. Each restricted stock unit represents a contingent right to receive one share of Otter Tail Corporation stock.

2. These shares were withheld by the Corporation to pay taxes due upon vesting of this award, exempt pursuant to Rule 16b-3(e).

3. Total direct holdings include shares acquired through the Dividend Reinvestment Plan, the Employee Stock Purchase Plan and shares acquired pursuant to Stock Options, Restricted Stock Awards, Restricted Stock Units and Performance Share Awards.

4. The restricted stock units vest in four equal annual installments beginning the date shown above.

Remarks:

	/s/ Charles S. MacFarlane by James A. Versteeg, Attorney-in-Fact	02/09/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

Source: View Original Filing on SEC EDGAR

FAQ

What insider transactions did OTTR President & CEO Charles MacFarlane report?

Charles S. MacFarlane reported routine equity award activity, including restricted stock units converting into 9,125 Otter Tail common shares on February 6, 2026. The company then withheld 4,277 shares at $87.83 per share to cover taxes due on the vesting.

How many Otter Tail (OTTR) shares does the CEO hold after this Form 4?

After the reported transactions, Charles S. MacFarlane directly held 227,412 Otter Tail common shares. He also had indirect ownership of 75,459 shares through a Spousal Lifetime Access Trust and 3,051 shares through an employee stock ownership plan.

What does the tax withholding transaction on OTTR shares represent?

The tax withholding transaction reflects 4,277 Otter Tail shares retained by the company at $87.83 per share to pay taxes upon vesting. This is coded "F" on Form 4 and is described as shares withheld by the corporation under Rule 16b-3(e).

What are the restricted stock units reported by OTTR’s CEO on this Form 4?

The filing shows multiple restricted stock unit grants that vested and converted into common shares on February 6, 2026. Each restricted stock unit represents a contingent right to receive one Otter Tail share, vesting in four equal annual installments from the grant date.