Starboard Delivers Letter to Knife River

Highlights Knife River’s Widening Margin Gap with Peers and Calls for Commitment to at Least 22% Adjusted EBITDA Margins by FY2029

Calls for Greater Board Accountability and More Rigorous Management Incentives Aligned with Shareholder Commitments

Starboard Value LP (together with its affiliates, "Starboard"), a stockholder of Knife River Corporation ("Knife River" or the "Company") (NYSE:KNF), today announced that it has delivered a letter to the Company’s Board of Directors.

The full text of Starboard's letter to the Company can be viewed here.

About Starboard Value LP

Starboard Value LP is an investment adviser with a focused and differentiated fundamental approach to investing in publicly traded companies. Starboard invests in deeply undervalued companies and actively engages with management teams and boards of directors to identify and execute on opportunities to unlock value for the benefit of all shareholders.

View source version on businesswire.com: https://www.businesswire.com/news/home/20261030074103/en/

Investor:

Peter Feld, (212) 201-4878

Gavin Molinelli, (212) 201-4828

www.starboardvalue.com



Media:

Prosek Partners

Andy Merrill

amerrill@prosek.com

Brian Schaffer

bschaffer@prosek.com