KNIFE RIVER SEPARATION

6/1/2023: MDU Resources Completes Spinoff of Knife River

5/12/2023: MDU Resources Announces Knife River Form 10 Registration Statement Declared Effective

5/4/2023: MDU Resources Board of Directors Approves Separation of Knife River; Declares Distribution of Shares for Knife River

4/25/2023: MDU Resources Announces Closing of Knife River Holding Company’s $425 Million Notes Offering in Connection With Anticipated Knife River Spinoff

4/11/2023: MDU Resources Announces Pricing of Knife River Holding Company’s $425 Million Notes Offering in Connection With Anticipated Knife River Spinoff

4/10/2023: MDU Resources Announces Launch of Knife River Holding Company’s Notes Offering in Connection With Anticipated Knife River Spinoff

4/7/2023: MDU Resources Announces Anticipated Board of Directors for Knife River

3/10/2023: Knife River to be Listed Under Ticker KNF on NYSE Upon Spinoff From MDU Resources

2/16/2023: MDU Resources Board of Directors Names Leadership for Knife River Upon Separation

1/10/2023: MDU Resources Names Nathan Ring CFO of Knife River Corporation

12/15/2022: MDU Resources Expects Second Quarter Spinoff of Knife River Corp.; Strategic Review of MDU Construction Services Group Underway

11/17/2022: MDU Resources Names Brian Gray President of Knife River Corporation; David Barney Remains CEO

8/4/2022: MDU Resources Announces Plan to Separate Knife River, Creating Two Focused, Independent Publicly Traded Companies