CHARLES S. MACFARLANE - 06 Feb 2026 Form 4 Insider Report for Otter Tail Corp (OTTR)

Role
President & CEO
Signature
/s/ Charles S. MacFarlane by James A. Versteeg, Attorney-in-Fact
Issuer symbol
OTTR
Transactions as of
06 Feb 2026
Net transactions value
-$375,649
Form type
4
Filing time
09 Feb 2026, 17:05:34 UTC
Previous filing
13 Feb 2025
Next filing
12 Feb 2026
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
MACFARLANE CHARLES S President & CEO 215 SOUTH CASCADE STREET, FERGUS FALLS /s/ Charles S. MacFarlane by James A. Versteeg, Attorney-in-Fact 09 Feb 2026 0001278053

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction OTTR Common Stock Options Exercise +9,125 +4.1% 231,689 06 Feb 2026 Direct F1
transaction OTTR Common Stock Tax liability $375,649 -4,277 -1.8% $87.83 227,412 06 Feb 2026 Direct F2, F3
holding OTTR Common Stock 75,459 06 Feb 2026 by Spousal Lifetime Access Trust
holding OTTR Common Stock 3,051 06 Feb 2026 by ESOP

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction OTTR Restricted Stock Units Options Exercise $0 -2,175 -100% $0.000000 0 06 Feb 2026 Common Stock 0 Direct F1, F4
transaction OTTR Restricted Stock Units Options Exercise $0 -2,500 -50% $0.000000 2,500 06 Feb 2026 Common Stock 2,500 Direct F1, F4
transaction OTTR Restricted Stock Units Options Exercise $0 -1,975 -33% $0.000000 3,950 06 Feb 2026 Common Stock 3,950 Direct F1, F4
transaction OTTR Restricted Stock Units Options Exercise $0 -2,475 -25% $0.000000 7,425 06 Feb 2026 Common Stock 7,425 Direct F1, F4
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Each restricted stock unit represents a contingent right to receive one share of Otter Tail Corporation stock.
F2 These shares were withheld by the Corporation to pay taxes due upon vesting of this award, exempt pursuant to Rule 16b-3(e).
F3 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.
F4 The restricted stock units vest in four equal annual installments beginning the date shown above.