Otter Tail Corp

Q: Jun 30 2026

Q: Mar 31 2026

FY: Dec 31 2025

FY: Dec 31 2025

Q: Sep 30 2025

Q: Jun 30 2025

Q: Mar 31 2025

FY: Dec 31 2024

Q: Sep 30 2024

Q: Jun 30 2024

Q: Mar 31 2024

FY: Dec 31 2023

Q: Sep 30 2023

Q: Jun 30 2023

Q: Mar 31 2023

FY: Dec 31 2022

Q: Sep 30 2022

Q: Jun 30 2022

Q: Mar 31 2022

FY: Dec 31 2021

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Results of Operations and Financial Condition

Entry into a Material Definitive Agreement

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

Entry into a Material Definitive Agreement

Other Events

Results of Operations and Financial Condition

Submission of Matters to a Vote of Security Holders

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Entry into a Material Definitive Agreement

Results of Operations and Financial Condition

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Results of Operations and Financial Condition

Results of Operations and Financial Condition

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

Other Events

Results of Operations and Financial Condition

Submission of Matters to a Vote of Security Holders

Entry into a Material Definitive Agreement

Results of Operations and Financial Condition

Automatic Shelf Registration

Automatic Shelf Registration

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Automatic Shelf Registration

Automatic Shelf Registration

Prospectus Supplement for Primary Offering

Automatic Shelf Registration

Automatic Shelf Registration

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Automatic Shelf Registration

Automatic Shelf Registration

Prospectus Supplement for Primary Offering

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Prospectus Supplement for Primary Offering

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Certification of termination of registration of a class of securities (Section 12(g))

Prospectus Supplement for Primary Offering

Automatic Shelf Registration

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Preliminary Proxy Statement

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Additional Information for Proxy Statement/ Votes

Required Information in Proxy Statement

Definitive Proxy Statement

Definitive Proxy Statement

Definitive Proxy Statement

Preliminary Proxy Statement

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Definitive Proxy Statement

Definitive Proxy Statement

Definitive Proxy Statement

Definitive Proxy Statement

Definitive Proxy Statement

KNUTSON PAUL L

KNUTSON PAUL L

KNUTSON PAUL L

STATE STREET CORP

VANGUARD CAPITAL MANAGEMENT LLC

VANGUARD PORTFOLIO MANAGEMENT LLC

Nelson Tyler J

Smestad Jennifer O.

ROGELSTAD TIMOTHY J

Wahlund Todd R

PARTAIN NATHAN I

Nelson Tyler J

Rasche Steven P

Ludford Mary E

Crain Jeanne H

LeBeau Michael E

Clark Christopher B

Johnson Kathryn O

WEBB THOMAS J

ERICKSON JOHN D

Specialized Disclosure Report

Annual Report Scanned (Paper)

Specialized Disclosure Report

Annual Report Scanned (Paper)

Specialized Disclosure Report

Annual Report Scanned (Paper)

Specialized Disclosure Report

Annual Report Scanned (Paper)

Specialized Disclosure Report

Specialized Disclosure Report

Specialized Disclosure Report

Specialized Disclosure Report

Specialized Disclosure Report

No description available

Specialized Disclosure Report

Specialized Disclosure Report

Post-effective amendment to an automatic shelf registration statement

No description available

Specialized Disclosure Report

Annual Report Scanned (Paper)