Knife River Corp

Index

Cautionary Statement Regarding Forward-Looking Statements

This Annual Report contains forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. Forward-looking statements are all statements other than statements of historical fact, including without limitation those statements that are identified by the words "anticipates," "estimates," "expects," "intends," "plans," "predicts" and similar expressions, and include statements concerning plans, projections, objectives, goals, strategies, future events or performance, and underlying assumptions (many of which are based, in turn, upon further assumptions), including, but not limited to, with respect to EDGE, growth, shareholder value creation, expected long-term goals, backlog margin, statements related to the acquisition of Strata (as defined later) or other proposed strategies and other statements that are other than statements of historical facts. From time to time, the Company may publish or otherwise make available forward-looking statements of this nature.

Forward-looking statements involve risks and uncertainties, which could cause actual results or outcomes to differ materially from those expressed. The Company's expectations, beliefs and projections are expressed in good faith and are believed by the Company to have a reasonable basis, including without limitation, management's examination of historical operating trends, data contained in the Company's records and other data available from third parties. Nonetheless, the Company's expectations, beliefs or projections, including, but not limited to, with respect to EDGE, growth, shareholder value creation, expected long-term goals, backlog margin, statements related to the acquisition of Strata or other proposed strategies, may not be achieved or accomplished and changes in such assumptions and factors could cause actual future results to differ materially.

Undo reliance should not be placed on forward-looking statements and any forward-looking statement contained in this document speaks only as of the date on which the statement is made, and the Company undertakes no obligation to update any forward-looking statement or statements to reflect events or circumstances that occur after the date on which the statement is made or to reflect the occurrence of unanticipated events, except as required by law. New factors emerge from time to time, and it is not possible for management to predict all the factors, nor can it assess the effect of each factor on the Company's business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statement. All forward-looking statements, whether written or oral and whether made by or on behalf of the Company, are expressly qualified by the risk factors and cautionary statements reported in the section entitled "Item 1A. Risk Factors" and subsequent filings with the SEC.

v

Index

Summary of Risk Factors

An investment in Knife River is subject to a number of risks. Set forth below is a high-level summary of some, but not all, of these risks. Please read the information in ”Item 1A. Risk Factors” for a more thorough description of these risks.

Operations, Growth and Competitive Risks

•We operate in a highly competitive industry.

•We may not be able to secure, permit or economically mine strategically located aggregate reserves.

•Our business is seasonal and subject to weather conditions that could adversely affect our operations.

•We are exposed to risk of loss resulting from nonpayment and/or nonperformance of our customers and counterparties.

•Our success depends, in part, on our ability to execute on our acquisition strategy, to successfully integrate acquired businesses and to retain key employees of acquired businesses.

•Technology disruptions or cyberattacks could adversely impact operations.

•Artificial intelligence presents risks and challenges that can impact our business.

•We may be unable to protect our intellectual property.

•Pandemics, including COVID-19, may have a negative impact on our business operations.

Economic and Political Risks

•Significant changes in prices for commodities, labor, or other production and delivery inputs could negatively affect our businesses.

•Supply chain disruptions may adversely affect our operations.

•Our business is based in large part on government-funded infrastructure projects and building activities, and any reductions or reallocation of spending or related subsidies in these areas could have an adverse effect on us.

•Economic volatility affects our operations, as well as the demand for our products and services.

Legal and Regulatory Compliance Risks

•We may be negatively impacted by pending and/or future litigation, claims or investigations.

•Unexpected factors affecting self-insurance claims and reserve estimates.

•Our operations could be negatively impacted by import tariffs and/or other government mandates.

•Our operations are subject to environmental laws and regulations.

•Our operations could be adversely impacted by severe weather events, including as a result of climate change.

•Stakeholder actions and increased regulatory activity related to environmental and other sustainability matters could adversely impact our operations.

•Changes in tax law may negatively affect our business.

Human Capital Risks

•Our operations may be negatively affected if we are unable to obtain, develop and retain key personnel and skilled labor forces.

•Increasing costs associated with health care plans may adversely affect our results of operations.

vi

Index

Financial and Accounting Risks

•Aggregate resource and reserve calculations are estimates and subject to uncertainty.

•Backlog may not accurately represent future revenue and gross margin.

•We operate in a capital-intensive industry and are subject to capital market and interest rate risks.

•Financial market changes could impact our defined benefit pension plans and obligations.

•Costs related to obligations under MEPPs could have a material negative effect on our results of operations and cash flows.

•We have substantial indebtedness and may incur substantial additional indebtedness.

•Despite our current level of indebtedness, we may be able to incur substantially more debt.

•A lowering or withdrawal of the ratings, outlook or watch assigned to us or our debt by rating agencies may increase our future borrowing costs and reduce our access to capital.

Separation Risks

•We have minimal history of operating as an independent, public company.

•We could be subject to significant tax liabilities or be required to indemnify MDU Resources for material taxes, and other related amounts, in connection with the Separation.

•United States federal income tax consequences may restrict our ability to engage in certain desirable strategic or capital-raising transactions after the Separation.

•We may not achieve some or all of the expected benefits of the Separation.

Shareholder Risks

•The trading market for our common stock has existed only a short period, and the market price and trading volume of our common stock may fluctuate significantly.

•Stockholder percentage of ownership in us may be diluted in the future.

•We cannot guarantee the timing, declaration, amount or payment of dividends, if any.

•Exclusive forum selection provisions in our amended and restated bylaws could discourage lawsuits against us and our directors and officers.

•Provisions in our amended and restated certificate of incorporation and amended and restated bylaws and Delaware law may prevent or delay an acquisition of Knife River.

Strata Acquisition Risks

•We may not be able to fully realize the benefits from the Acquisition.

•The announcement and pendency of the Acquisition may have an adverse effect on our results of operations.

•The failure to complete the Acquisition in a timely manner or at all could negatively impact the market price of our common stock.

•The incurrence by us of substantial indebtedness in connection with the financing of the Acquisition may have an adverse impact on our liquidity.

•We have incurred, and will continue to incur, transaction fees and costs in connection with the Acquisition.

vii

Index

PART I