MDU US Equity☆

mdu-20241231

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

For the fiscal year ended December 31, 2024

OR

For the transition period from _____________ to ______________

Commission file number 1-03480

MDU RESOURCES GROUP, INC.

(Exact name of registrant as specified in its charter)

1200 West Century Avenue

P.O. Box 5650

Bismarck, North Dakota58506-5650

(Address of principal executive offices)

(Zip Code)

(701) 530-1000

(Registrant's telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading symbol(s) Name of each exchange on which registered

Common Stock, par value $1.00 per share MDU New York Stock Exchange

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☒ No ☐.

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐No☒.

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes☒ No ☐.

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes☒ No ☐.

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer ☒ Accelerated filer ☐

Non-accelerated filer ☐ Smaller reporting company ☐

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant's executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ☐ No ☒.

State the aggregate market value of the voting common stock held by non-affiliates of the registrant as of June 28, 2024: $5,095,923,531, which does not reflect MDU Resources Group, Inc.'s market value after the separation and distribution of Everus Construction Group, Inc. on October 31, 2024.

Indicate the number of shares outstanding of the registrant's common stock, as of February 13, 2025: 204,331,170 shares.

DOCUMENTS INCORPORATED BY REFERENCE

Relevant portions of the registrant's 2025 Proxy Statement, to be filed no later than 120 days from December 31, 2024, are incorporated by reference in Part III, Items 10, 11, 12, 13 and 14 of this Report.

Contents

Part I Page

Definitions 4

Cautionary Note Regarding Forward-Looking Statements 7

Items 1 and 2 Business and Properties 7

General 7

Electric 11

Natural Gas Distribution 14

Pipeline 17

Discontinued Operations 18

Item 1A Risk Factors 18

Item 1B Unresolved Staff Comments 27

Item 1C Cybersecurity 28

Item 3 Legal Proceedings 29

Part II

Item 6 Reserved 30

Item 7A Quantitative and Qualitative Disclosures About Market Risk 56

Item 8 Financial Statements and Supplementary Data 57

Consolidated Statements of Income 62

Consolidated Statements of Comprehensive Income 63

Consolidated Balance Sheets 64

Consolidated Statements of Equity 65

Consolidated Statements of Cash Flows 66

Notes to Consolidated Financial Statements 67

1. Basis of Presentation 67

2. Significant Accounting Policies 68

3. Discontinued Operations 73

4. Revenue from Contracts with Customers 76

5. Property, Plant and Equipment 77

6. Regulatory Assets and Liabilities 78

7. Environmental Allowances and Obligations 79

8. Goodwill and Other Intangible Assets 79

9. Fair Value Measurements 80

11. Asset Retirement Obligations 84

13. Stock-Based Compensation 85

14. Accumulated Other Comprehensive Loss 87

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Contents

Part II (continued) Page

16. Cash Flow Information 89

17. Business Segment Data 90

18. Employee Benefit Plans 94

19. Jointly Owned Facilities 101

20. Regulatory Matters 102

21. Commitments and Contingencies 103

Item 9A Controls and Procedures 107

Item 9B Other Information 107

Item 9C Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 107

Part III

Item 10 Directors, Executive Officers and Corporate Governance 108

Item 11 Executive Compensation 108

Item 14 Principal Accountant Fees and Services 108

Part IV

Item 15 Exhibits, Financial Statement Schedules 109

MDU Resources Group, Inc. Form 10-K 3

Definitions

Abbreviation or Acronym

AFUDC Allowance for funds used during construction

Applied Digital Applied Digital Corporation

Army Corps U.S. Army Corps of Engineers

ASC FASB Accounting Standards Codification

ASU FASB Accounting Standards Update

Bcf Billion cubic feet

CERCLA Comprehensive Environmental Response, Compensation and Liability Act

CIO Chief Information Officer

Code U.S. Internal Revenue Code

CODM Chief Operating Decision Maker

Company MDU Resources Group, Inc.

COVID-19 Coronavirus disease 2019

CyROC Cyber Risk Oversight Committee

DC Circuit Court U.S Court of Appeals for the D.C. Circuit

dk Decatherm

EBITDA Earnings before interest, taxes, depreciation and amortization

EIN Employer Identification Number

EPA U.S. Environmental Protection Agency

ERISA Employee Retirement Income Security Act of 1974, as amended

ERM Enterprise risk management

ESG Environmental, social and governance

Exchange Act Securities Exchange Act of 1934, as amended

FASB Financial Accounting Standards Board

FERC Federal Energy Regulatory Commission

FIP Funding improvement plan

GAAP Accounting principles generally accepted in the United States of America

GHG Greenhouse gas

GVTC Generation Verification Test Capacity

4 MDU Resources Group, Inc. Form 10-K

Definitions

IBEW International Brotherhood of Electrical Workers

ICWU International Chemical Workers Union

IPUC Idaho Public Utilities Commission

IRA Inflation Reduction Act

IRP Integrated Resource Plan

IRS Internal Revenue Service

Item 8 Financial Statements and Supplementary Data

K-Plan Company's 401(k) Retirement Plan

kW Kilowatts

kWh Kilowatt-hour

kV Kilovolts

Leading with Integrity Guide Company's code of business conduct

LIBOR London Inter-bank Offered Rate

MEPP Multiemployer pension plan

MMcf Million cubic feet

MMdk Million dk

MNPUC Minnesota Public Utilities Commission

MPPAA Multiemployer Pension Plan Amendments Act of 1980

MTPSC Montana Public Service Commission

MW Megawatt

NDDEQ North Dakota Department of Environmental Quality

NDPSC North Dakota Public Service Commission

NERC North American Electric Reliability Corporation

NYSE New York Stock Exchange

ODEQ Oregon Department of Environmental Quality

OPUC Oregon Public Utility Commission

PCAOB Public Company Accounting Oversight Board

PCBs Polychlorinated biphenyls

PHMSA Pipeline and Hazardous Material Safety Administration

Proxy Statement Company's 2025 Proxy Statement

PRP Potentially Responsible Party

PSAs Performance share awards

RCRA Resource Conservation and Recovery Act

RNG Renewable natural gas

RP Rehabilitation plan

MDU Resources Group, Inc. Form 10-K 5

Definitions

RSUs Restricted stock units

SBCC State Building Code Council

SDPUC South Dakota Public Utilities Commission

SEC U.S. Securities and Exchange Commission

Securities Act Securities Act of 1933, as amended

Sheridan System A separate electric system owned by Montana-Dakota

SOFR Secured Overnight Financing Rate

TSA Transportation Security Administration

VIE Variable interest entity

Washington DOE Washington State Department of Ecology

WBI Energy WBI Energy, Inc., an indirect wholly-owned subsidiary of Centennial

WUTC Washington Utilities and Transportation Commission

WYDEQ Wyoming Department of Environmental Quality

WYPSC Wyoming Public Service Commission

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Cautionary Note Regarding Forward-Looking Statements

This Form 10-K contains forward-looking statements within the meaning of the federal securities laws. Other than statements of historical facts, all statements which address activities, events or developments that the Company anticipates will or may occur in the future, including, but not limited to, such things as estimates for growth, stockholder value creation, the Company's "CORE" strategy, capital expenditures, financial guidance and other such matters, are forward-looking statements. These forward-looking statements are based on many assumptions and factors, which are detailed in the Company's filings with the SEC.

While made in good faith, these forward-looking statements are based largely on the Company's expectations and judgments and are subject to a number of risks and uncertainties, many of which are unforeseeable and beyond our control. For additional discussion regarding risks and uncertainties, that may affect forward-looking statements, see Item 1A - Risk Factors. Any changes in such assumptions or factors could produce significantly different results. Undue reliance should not be placed on forward-looking statements, which speak only as of the date they are made. Except as required by applicable law, the Company undertakes no obligation to update the forward-looking statements, whether as a result of new information, future events or otherwise.

Items 1 and 2. Business and Properties

General

The Company is a pure-play regulated energy delivery business upon the completed separations of both its construction materials and contracting and construction services businesses, as further discussed below. Its principal executive offices are located at 1200 West Century Avenue, P.O. Box 5650, Bismarck, North Dakota 58506-5650, telephone (701) 530-1000.

Montana-Dakota was incorporated under the state laws of Delaware in 1924, marking its 100th year in business on March 14, 2024. The Company was incorporated under the state laws of Delaware in 2018. Upon the completion of the Holding Company Reorganization, Montana-Dakota became a subsidiary of the Company. The Company adopted a new mission statement in early 2025, "With integrity, deliver value as a leading energy provider and employer of choice."

Through a strategy focusing on its "CORE," the Company strives to deliver superior value and achieve industry-leading performance as a pure-play regulated energy delivery company, while pursuing organic growth opportunities. The Company's "CORE" strategy prioritizes customers and communities, operational excellence, returns focused initiatives and an employee driven culture. The Company generates, transmits and distributes electricity and provides natural gas distribution, transportation and storage services. These businesses are regulated by state public service commissions and/or the FERC.

As part of the Company's continual review of its business, the Company announced strategic initiatives to enhance stockholder value. On May 31, 2023, the Company executed the separation of Knife River, the construction materials and contracting business, from the Company, resulting in Knife River becoming an independent, publicly-traded company. On October 31, 2024, the Company completed the separation of Everus, the construction services business, from the Company, resulting in Everus becoming an independent, publicly-traded company.

As of December 31, 2024, the Company was organized into three reportable business segments. These business segments include: electric, natural gas distribution and pipeline. The Company's business segments are determined based on the Company's method of internal reporting, which generally segregates the business activities by differences in products and services. The internal reporting of these segments is defined based on the reporting and review process used by the Company's chief executive officer.

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The Company, through its wholly-owned subsidiary, MDU Energy Capital, owns Montana-Dakota, Cascade and Intermountain. The electric segment is comprised of Montana-Dakota while the natural gas distribution segment is comprised of Montana-Dakota, Cascade and Intermountain.

The Company, through its wholly-owned subsidiary, Centennial, owns WBI Energy and Centennial Capital. WBI Energy is the pipeline segment and Centennial Capital is reflected in the Other category.

The financial results and data applicable to each of the Company's business segments, as well as their financing requirements, are set forth in Item 7 - MD&A and Item 8 - Note 17.

The Company's material properties, which are of varying ages and are of different construction types, are generally in good condition, are well maintained and are generally suitable and adequate for the purposes for which they are used.

Human Capital Management The Company continues to focus on building a strong workforce. This means building a strong team of employees with a focus on safety and integrity and a commitment to a respectful workplace. As of December 31, 2024, the Company had 2,052 employees.

Many of the Company's employees are represented by collective-bargaining agreements and the Company is committed to establishing constructive dialogue with this representation and bargaining in good faith. The majority of the collective-bargaining agreements contain provisions that prohibit work stoppages or strikes and provide dispute resolution through binding arbitration in the event of an extended disagreement.

The following information is as of December 31, 2024.

Montana-Dakota IBEW 296 Effective through April 30, 2026

Cascade ICWU 182 Effective through March 31, 2028

WBI Energy Transmission IBEW 72 Effective through April 30, 2027

Respectful Workplace The Company is committed to an environment that respects the differences and embraces the strengths of its employees. Essential to the Company's success is its ability to attract, retain and engage the best people from a broad range of backgrounds and build an inclusive culture where all employees feel valued and contribute their best. The Company requires employees to participate in its Leading with Integrity training which provides training on the Company's code of conduct.

The Company's goals related to a respectful workplace:

•Enhance collaboration efforts through cooperation and sharing of best practices to create new ways of meeting employee, customer and stockholder needs.

•Increase productivity and profitability through the creation of a work environment which values all perspectives and methods of accomplishing work.

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The Company also promotes recognition of team members through the following awards:

Building People Building a strong workforce begins with employee recruitment. The Company hires and trains employees to have the skills, abilities and motivation to achieve the results needed for their jobs. Each job is important and part of a coordinated team effort to accomplish the organization's objectives. The Company uses a variety of means to recruit new employees for open positions including posting on the Company's website. Other sources for employee recruitment include employee referrals, union workforce, direct recruitment, advertising, social media, career fairs, partnerships with colleges and technical schools, job service organizations and associations connected with a variety of professions. The Company also uses internship programs to introduce individuals to the Company's business operations and provide a possible source of future employees.

Building a strong workforce also requires developing employees in their current positions and for future advancement. The Company provides opportunities for advancement through job mobility, succession planning and promotions both within and between business segments. The Company provides employees the opportunity to further develop and grow through various forms of training, mentorship programs and internship programs, among other things.

To attract and retain employees, the Company offers:

The chief executive officer engages in employee tours at Company locations and the Company conducts employee surveys to hear and gauge employee opinions on issues such as fairness, camaraderie and pride in the workplace. Survey responses are compiled and evaluated at various levels throughout the Company to develop action plans to address areas of concern raised by employees.

Safety Safety is one of the Company's corporate values. The Company is committed to safety and health in the workplace. To ensure safe work environments, the Company provides training, resources and appropriate follow-up on any unsafe conditions or actions. To facilitate a strong safety culture, the Company established its Safety Leadership Council. In addition to the Safety Leadership Council, the Company has policies and training that support safety in the workplace including training on safety matters through classroom and toolbox meetings on job sites. The Company utilizes safety compliance in the evaluation of employees, which includes management, and recognizes employee safety through safety award programs.

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Accident and safety statistical information is regularly reported to management and the board of directors.

For more information on the Company's sustainability goals, programs and performance, see the Company's Sustainability Report on its website, which is not incorporated by reference herein.

Technology The Company uses technology in substantially all aspects of its business operations and requires uninterrupted operation of information technology systems and network infrastructure. These systems may be vulnerable to failures or unauthorized access. The Company has policies, procedures and processes designed to strengthen and protect these systems, which include the Company’s enterprise information technology and operation technology groups continually evaluating new tools and techniques to reduce the risk and potential impacts of a cyber breach.

For a discussion of the Company's risks related to cybersecurity, see Item 1A - Risk Factors. For more information on the Company's approach to cybersecurity, see Item 1C - Cybersecurity.

Available Information The Company maintains a corporate website at www.mdu.com. The Company's filings with the SEC, including its annual report on Form 10-K, it's quarterly reports on Form 10-Q and current reports on Form 8-K, and all amendments to those reports are available free of charge through this website as soon as reasonably practicable after they are filed with or furnished to the SEC. The Governance section of the website contains the Company's Corporate Governance Guidelines, committee charters, and the Leading with Integrity Guide for directors, officers, and employees, and is incorporated herein by reference. Copies of these documents may also be obtained free of charge upon written request to the Company's corporate secretary at MDU Resources Group, Inc., P.O. Box 5650, Bismarck, North Dakota 58506.The information available on, or accessible through, the Company's website is not part of this Annual Report on Form 10-K.

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Electric

Retail electric rates, service, accounting and certain securities issuances are subject to regulation by the MTPSC, NDPSC, SDPUC and WYPSC. The interstate transmission and wholesale electric power operations of Montana-Dakota are also subject to regulation by the FERC under provisions of the Federal Power Act, as are interconnections with other utilities and power generators, the issuance of certain securities, accounting, cybersecurity and other matters.

Through MISO, Montana-Dakota has access to wholesale energy, ancillary services and capacity markets for its interconnected system. MISO is a regional transmission organization responsible for operational control of the transmission systems of its members. MISO provides security center operations, tariff administration and operates day-ahead and real-time energy markets, ancillary services and capacity markets. As a member of MISO, Montana-Dakota's generation is sold into the MISO energy market and its energy needs are purchased from that market.

The retail customers served and respective revenues by class for the electric business were as follows:

CustomersServed Revenues CustomersServed Revenues CustomersServed Revenues

(Dollars in thousands)

Other electric revenues, which are largely transmission-related revenues, for Montana-Dakota were $58.7 million, $53.6 million and $48.7 million for the years ended December 31, 2024, 2023 and 2022, respectively.

The percentage of electric retail revenues by jurisdiction was as follows:

Wyoming 9 % 9 % 9 %

South Dakota 5 % 5 % 5 %

System Supply, System Demand and CompetitionThrough an interconnected electric system, Montana-Dakota serves markets in portions of North Dakota, Montana and South Dakota. These markets are highly seasonal and sales volumes depend largely on the weather. Additionally, the average customer consumption has tended to decline due to increases in energy efficient lighting and appliances being installed. In mid-2023 a data center began operating in the Company's service territory which led to an increase in sales volumes. As of December 31, 2024, the interconnected system consisted of 13 electric generating units at 10 facilities and two small portable diesel generators. Additional details are included in the table that

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follows. For 2024, Montana-Dakota's total ZRCs, including its firm purchase power contracts, were 536.8. Montana-Dakota's planning reserve margin requirement within MISO was 528.6 ZRCs for 2024. The maximum electric peak demand experienced to date attributable to Montana-Dakota's sales to retail customers on the interconnected system was 764,823 kW in January 2024. Montana-Dakota's latest forecast for its interconnected system indicates that its annual peak will continue to occur during the summer. Additional energy is purchased as needed, or in lieu of generation if more economical, from the MISO market. In 2024, Montana-Dakota purchased approximately 61 percent of its net kWh needs for its interconnected system through the MISO market.

Through the Sheridan System, Montana-Dakota serves Sheridan, Wyoming, and neighboring communities. The maximum peak demand experienced to date attributable to Montana-Dakota sales to retail customers on that system was approximately 69,991 kW in July 2024. Montana-Dakota has a power supply contract with Black Hills Power, Inc. to purchase up to 49,000 kW of capacity annually through December 31, 2028. Wygen III also serves a portion of the needs of Montana-Dakota's Sheridan-area customers.

Approximately 38 percent of the electricity delivered to customers from Montana-Dakota's owned generation in 2024 was from renewable resources. Although Montana-Dakota's generation resource capacity has increased to serve the needs of its customers, the carbon dioxide emission intensity of its electric generation resource fleet has been reduced by approximately 38 percent since 2005 through the addition of renewable generation and with the retirement of aging coal-fired electric generating units, as further discussed below.

In February 2022, the Company ceased operations of Units 1 and 2 at Heskett Station near Mandan, North Dakota, and decommissioning was completed in December 2023. In May 2022 Montana-Dakota began construction of Heskett Unit 4, an 88-MW simple-cycle natural gas-fired combustion turbine peaking unit at the existing Heskett Station near Mandan, North Dakota. Heskett Unit 4 was in service and fully operational in July 2024.

The following table sets forth details applicable to the Company's electric generating stations:

Interconnected System:

North Dakota:

South Dakota:

Montana:

Glendive Combustion turbine Natural gas / diesel 75,522 53.9 3,805

Miles City Combustion turbine Natural gas / diesel 23,150 16.2 440

Portable Units (2) Reciprocating internal combustion engine Diesel 3,650 3.5 31

Sheridan System:

Wyoming:

(a)Interconnected system only. MISO requires generators to obtain their seasonal capability through the GVTC. The GVTC is then converted to ZRCs by applying each generator's forced outage factor against its GVTC. Wind generator's ZRCs are calculated based on a wind capacity study performed annually by MISO. ZRCs are used to meet supply obligations within MISO.

(b)Reflects Montana-Dakota's ownership interest.

The owners of Coyote Station, including Montana-Dakota, have a contract with Coyote Creek for coal supply to the Coyote Station that expires December 2040. Montana-Dakota estimates the Coyote Station coal supply agreement to be approximately 1.5 million tons per contract year. For more information, see Item 8 - Note 21.

The owners of Big Stone Station, including Montana-Dakota, have a coal supply agreement with Navajo Transitional Energy Company, LLC to meet all of the Big Stone Station's fuel requirements through 2026. Montana-Dakota estimates the Big Stone Station coal supply agreement to be approximately 1.5 million tons per contract year.

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Montana-Dakota has a coal supply agreement with Wyodak Resources Development Corp., to supply the coal requirements of Wygen III at contracted pricing through June 1, 2060. Montana-Dakota estimates the maximum annual coal consumption of the facility to be approximately 585,000 tons.

Montana-Dakota has power purchase agreements that run through 2045, including agreements entered into during the retirement of the Lewis and Clark Station and Heskett Units 1 and 2 and through the construction of Heskett Unit 4.

Montana-Dakota expects that it has secured adequate capacity available through existing baseload generating stations, renewable generation, turbine peaking stations, demand reduction programs and firm contracts to meet the peak customer demand requirements of its customers. Based upon current MISO resource adequacy rules, Montana-Dakota expects that it has secured adequate capacity available through existing baseload generation, peaking stations, demand reduction programs and firm contracts to meet the peak customer demand. MISO's recently approved direct loss of load accreditation is showing the need of additional generating units by May of 2028. Future capacity needs are expected to be met by constructing new generation resources or acquiring additional capacity through power purchase contracts or the MISO capacity auction.

Montana-Dakota has major interconnections with its neighboring utilities and considers these interconnections adequate for coordinated planning, emergency assistance, exchange of capacity and energy and power supply reliability.

Montana-Dakota is subject to competition resulting from customer demands, technological advances and other factors in certain areas, from rural electric cooperatives, on-site generators, co-generators and municipally owned systems. In addition, competition in varying degrees exists between electricity and alternative forms of energy such as natural gas.

Montana-Dakota is not dependent on any single customer or group of customers for sales of its products and services, where the loss of which would have a material adverse effect on its business.

Regulatory Matters and Revenues Subject to RefundIn North Dakota, Montana, South Dakota and Wyoming, there are various recurring regulatory mechanisms with annual true-ups that can impact Montana-Dakota's results of operations, which also reflect monthly increases or decreases in electric fuel and purchased power costs (including demand charges). Montana-Dakota is deferring those electric fuel and purchased power costs that are greater or less than amounts presently being recovered through its existing rate schedules. Examples of these recurring mechanisms include: monthly Fuel and Purchased Power Tracking Adjustments, a fuel adjustment clause, and an annual Electric Power Supply Cost Adjustment. Such mechanisms generally provide that these deferred fuel and purchased power costs are recoverable or refundable through rate adjustments which are filed annually. Montana-Dakota's results of operations reflect 95 percent of the increases or decreases from the base purchased power costs and also reflect 85 percent of the increases or decreases from the base coal price, which is also recovered through the Electric Power Supply Cost Adjustment in Wyoming. For more information on regulatory assets and liabilities, see Item 8 - Note 6.

All of Montana-Dakota's wind resources pertaining to electric operations in North Dakota are included in a renewable resource cost adjustment rider. Montana-Dakota also has a transmission tracker in North Dakota to recover transmission costs associated with MISO and SPP, along with certain transmission investments not recovered through retail rates. The tracking mechanism has an annual true-up.

In South Dakota, Montana-Dakota recovers the South Dakota decommissioning regulatory asset through an Infrastructure Rider tracking mechanism that is subject to an annual true-up. Montana-Dakota also has in place in South Dakota a transmission tracker to recover transmission costs associated with MISO and SPP, that allows transmission investments not recovered through retail rates. This tracking mechanism also has an annual true-up.

In Montana, Montana-Dakota recovers in rates, through a tracking mechanism, its allocated share of Montana property-related taxes assessed to electric operations on an after-tax basis.

For more information on regulatory matters, see Item 8 - Note 20.

Environmental MattersMontana-Dakota's electric operations are subject to federal, state and local laws and regulations providing for air, water and solid waste pollution control; state facility-siting regulations; zoning and planning regulations of certain state and local authorities; federal and state health and safety regulations; and state hazard communication standards. The electric operations strive to be in compliance with these regulations.

Montana-Dakota's electric generating facilities have Title V Operating Permits, under the federal Clean Air Act, issued by the states in which they operate. Each of these permits has a five-year life. Near the expiration of these permits, renewal applications are submitted. Permits continue in force beyond the expiration date, provided the application for renewal is submitted by the required date, usually six months prior to expiration. The WYDEQ determined all units at the Neil Simpson Complex, where Wygen III is situated, are to be included within a combined Title V Operating Permit which was submitted in June 2022. Wygen III is currently allowed to operate under the facility's construction permit until the Title V Operating Permit is issued. A permit issuance date is not specified at this time. The Title V Operating Permit renewal application for Big Stone Station was submitted timely in October 2021 to the South Dakota Department of Agriculture & Natural Resources with the permit issuance date not specified at this time.

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State water discharge permits issued under the requirements of the federal Clean Water Act are maintained for power production facilities on the Missouri river. These permits also have five-year lives. Montana-Dakota renews these permits as necessary prior to expiration. Other permits held by these facilities may include an initial siting permit, which is typically a one-time, preconstruction permit issued by the state; state permits to dispose of combustion by-products; state authorizations to withdraw water for operations; and Army Corps permits to construct water intake structures. Montana-Dakota's Army Corps permits grant one-time permission to construct and do not require renewal. Other permit terms vary and the permits are renewed as necessary.

Montana-Dakota's electric operations are very small-quantity generators of hazardous waste and subject only to minimum regulation under the RCRA and when required notifies federal and state agencies of episodic generation events. Montana-Dakota routinely handles PCBs from its electric operations in accordance with federal requirements. PCB storage areas are registered with the EPA as required.

Montana-Dakota incurred approximately $2.6 million of capital expenditures in 2024 related to the closure of coal ash management units at Lewis & Clark Station and Heskett Station and to maintain air emissions compliance at its co-owned electric generating facilities. Environmental related capital expenditures are estimated to be $1.2 million, $1.9 million and $1.0 million in 2025, 2026 and 2027, respectively, for compliance requirements for coal ash management units at Lewis & Clark, Heskett, Coyote and Big Stone Stations. Montana-Dakota will maintain air emissions compliance at its co-owned electric generating facilities and does not expect to incur any material capital expenditures in 2025, 2026 and 2027 for compliance with current environmental laws and regulations. Montana-Dakota's capital and operational expenditures could also be affected by future environmental requirements, such as existing and proposed emissions reduction plans from the EPA. For more information, see Item 1A - Risk Factors and Item 7 - MD&A - Business Section Financial and Operating Data.

Natural Gas Distribution

The natural gas distribution operations are subject to regulation by the IPUC, MNPUC, MTPSC, NDPSC, OPUC, SDPUC, WUTC and WYPSC regarding retail rates, service, accounting and certain securities issuances.

The retail customers served and respective revenues by class for the natural gas distribution operations were as follows:

CustomersServed Revenues CustomersServed Revenues CustomersServed Revenues

(Dollars in thousands)

Transportation and other revenues for the natural gas distribution operations were $105.8 million, $75.3 million and $65.9 million for the years ended December 31, 2024, 2023 and 2022, respectively. In 2024, other revenue includes revenues from the sale of allocated emissions allowances.

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The percentage of the natural gas distribution operations' retail sales revenues by jurisdiction was as follows:

South Dakota 5 % 5 % 6 %

Minnesota 2 % 3 % 4 %

Wyoming 1 % 2 % 2 %

System Supply, System Demand and Competition The natural gas distribution operations serve retail natural gas markets, consisting principally of residential and commercial space and water heating users, in portions of Idaho, Minnesota, Montana, North Dakota, Oregon, South Dakota, Washington and Wyoming. These markets are highly seasonal and sales volumes depend largely on the weather, the effects of which are mitigated in certain jurisdictions by weather normalization mechanisms discussed later in Regulatory Matters. Additionally, the average customer consumption has tended to decline as more efficient appliances and furnaces are installed and as the Company has implemented conservation programs. In addition to the residential and commercial sales, the utilities transport natural gas for larger commercial and industrial customers who purchase their own supply of natural gas.

Competition resulting from customer demands, technological advances and other factors exists between natural gas and other fuels and forms of energy. The natural gas distribution operations have established various natural gas transportation service rates for their distribution businesses to retain interruptible commercial and industrial loads. These rates have enhanced the natural gas distribution operations' competitive posture with alternative fuels, although certain customers have bypassed the distribution systems by directly accessing transmission pipelines within close proximity. These bypasses do not have a material effect on results of operations.

The natural gas distribution operations and various distribution transportation customers obtain natural gas for their system requirements directly from producers, processors and marketers. The Company's purchased natural gas is supplied by a portfolio of contracts specifying market-based pricing and is transported under transportation agreements withWBI Energy Transmission, Northern Border Pipeline Company, Northwest Pipeline LLC, South Dakota Intrastate Pipeline, Northern Natural Gas, Gas Transmission Northwest LLC, Northwestern Energy, Viking Gas Transmission Company, Enbridge Westcoast Energy, Inc., Ruby Pipeline LLC, Foothills Pipe Lines Ltd., NOVA Gas Transmission Ltd, TC Energy Corporation, Northwest Natural, Black Hills Energy and TransCanada. The natural gas distribution operations have contracts for storage services to provide gas supply during the winter heating season and to meet peak day demand with various storage providers, including WBI Energy Transmission, Dominion Energy Questar Pipeline, LLC, Northwest Pipeline LLC and Northern Natural Gas. In addition, certain of the operations have entered into natural gas supply management agreements with various parties. Demand for natural gas, which is a widely traded commodity, has historically been sensitive to seasonal heating and industrial load requirements, as well as changes in market price. The Company believes supplies are adequate for the natural gas distribution operations to meet its system natural gas requirements for the next decade. This belief is based on current and projected domestic and regional supplies of natural gas and the pipeline transmission network currently available through its suppliers and pipeline service providers.

Regulatory MattersThe natural gas distribution operations' retail natural gas rate schedules contain clauses permitting adjustments in rates based upon changes in natural gas commodity, transportation and storage costs. Current tariffs allow for recovery or refunds of under- or over-recovered gas costs through rate adjustments which are filed annually.

In North Dakota and South Dakota, Montana-Dakota's natural gas tariffs contain weather normalization mechanisms applicable to certain firm customers that adjust the distribution delivery charges to reflect weather fluctuations during the November 1 through May 1 billing periods.

In Montana, Montana-Dakota recovers in rates, through a tracking mechanism, its allocated share of Montana property-related taxes assessed to natural gas operations on an after-tax basis.

In Minnesota and Washington, Great Plains and Cascade recover qualifying capital investments related to the safety and integrity of the pipeline systems through cost recovery tracking mechanisms. Washington's cost recovery tracking mechanism sunsets on March 1, 2025, with the multi-year natural gas rate case discussed in Item 8 - Note 20.

In Oregon, Cascade has a decoupling mechanism in place approved by the OPUC until January 1, 2025, with a review which was to be completed by September 30, 2024. On December 23, 2024, a filing was made to extend the decoupling mechanism until January 1, 2030. Cascade also has an earnings sharing mechanism with respect to its Oregon jurisdictional operations as required by the OPUC.

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On July 7, 2016, the WUTC approved a full decoupling mechanism where Cascade is allowed recovery of an average revenue per customer regardless of actual consumption. The mechanism also includes an earnings sharing component if Cascade earns in excess of its authorized return. On September 15, 2021, the WUTC extended the effectiveness of the decoupling mechanism until the earlier of the rate effective date resulting from Cascade's next full general rate case or August 31, 2025. Cascade filed its next general rate case on March 29, 2024. The multi-party rate case settlement agreement filed with the WUTC includes extension of the decoupling mechanism.

In Idaho, Intermountain has the authority to facilitate access for RNG producers to the Company's distribution system for the purpose of moving RNG to the producer's end-use customers.

For more information on regulatory matters, see Item 8 - Note 20.

Environmental MattersThe natural gas distribution operations are subject to federal, state and local environmental, facility-siting, zoning and planning laws and regulations. The natural gas distribution operations strive to be in compliance with these regulations.

The Company's natural gas distribution operations are very small-quantity generators of hazardous waste, and subject only to minimum regulation under the RCRA. A Washington state rule defines Cascade as a small-quantity generator, but regulation under the rule is similar to RCRA. Certain locations of the natural gas distribution operations routinely handle PCBs from their natural gas operations in accordance with federal requirements. PCB storage areas are registered with the EPA as required. Capital and operational expenditures for natural gas distribution operations could be affected in a variety of ways by new GHG legislation or regulation. In particular, such legislation or regulation would likely increase capital expenditures for energy efficiency and conservation programs and operational and gas supply costs associated with GHG emissions compliance. Natural gas distribution operations expect to recover the operational and capital expenditures for GHG regulatory compliance in rates consistent with the recovery of other reasonable costs of complying with environmental laws and regulations. For more information, see Item 7 - MD&A - Business Section Financial and Operating Data.

The natural gas distribution operations incurred $13.2 million of capital expenditures in 2024 to construct infrastructure supporting multiple RNG facilities, including the development and construction of a RNG facility at the Deschutes County Landfill near Bend, Oregon, and the implementation of an advanced mobile natural gas leak detection system, related to compliance with current environmental laws and regulations. Cascade and Montana-Dakota expect to incur environmental related capital expenditures of $13.1 million, $21.6 million and $15.9 million, in 2025, 2026 and 2027, respectively. The capital expenditures are to continue construction of infrastructure supporting multiple RNG production facilities, implement a thermal energy network pilot project, implement an additional advanced mobile natural gas leak detection system, and investigate a historic manufactured gas plant site. Except as to what may be ultimately determined with regard to the issues described in the following paragraph and the items noted, the natural gas distribution operations do not expect to incur any material capital expenditures related to compliance with current environmental laws and regulations through 2027.

Montana-Dakota has ties to six historic manufactured gas plants as a successor corporation or through direct ownership of the plant. Montana-Dakota is investigating possible soil and groundwater impacts due to the operation of two of these former manufactured gas plant sites. To the extent not covered by insurance, Montana-Dakota may seek recovery in its natural gas rates charged to customers for certain investigation and remediation costs incurred for these sites. Cascade has ties to eight historic manufactured gas plants as a successor corporation or through direct ownership of the plant. Cascade is involved in the investigation and remediation of one of these manufactured gas plants in Washington. To the extent not covered by insurance, Cascade will seek recovery of investigation and remediation costs through its natural gas rates charged to customers.

See Item 8 - Note 21 for further discussion of certain manufactured gas plant sites.

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Pipeline

A majority of the pipeline business is transacted in the Rocky Mountain and northern Great Plains regions of the United States.

System Supply, System Demand and CompetitionNatural gas supplies emanate from traditional and nontraditional production activities in the region from both on-system and off-system supply sources. Incremental supply from nontraditional sources, such as the Bakken area in Montana and North Dakota, have helped offset declines in traditional regional supply sources and supports WBI Energy Transmission's transportation and storage services. In addition, off-system supply sources are available through the Company's interconnections with other pipeline systems. WBI Energy Transmission continues to look for opportunities, such as the identified growth projects discussed in Item 7 - MD&A - Pipeline Outlook, to increase transportation and storage services through system expansion and/or other pipeline interconnections or enhancements that could provide future benefits.

WBI Energy Transmission's underground natural gas storage facilities have a certificated storage capacity of approximately 350 Bcf, including 193 Bcf of working gas capacity, 83 Bcf of cushion gas and 74 Bcf of native gas. These storage facilities enable customers to purchase natural gas throughout the year and meet winter peak requirements.

WBI Energy Transmission competes with several pipelines for its customers' transportation business and at times may discount rates in an effort to retain market share; however, the strategic location of its system near four natural gas producing basins and the availability of underground storage services, along with interconnections with other pipelines, enhances its competitive position.

Although certain of WBI Energy Transmission's firm customers, including its largest firm customer Montana-Dakota, serve relatively secure residential, commercial and industrial end-users, they generally all have some price-sensitive end-users that could switch to alternate fuels.

WBI Energy Transmission transports substantially all of Montana-Dakota's natural gas, primarily utilizing firm transportation agreements, which for 2024 represented 19 percent of WBI Energy Transmission's subscribed firm transportation contract demand. The majority of the firm transportation agreements with Montana-Dakota expire in June 2027. In addition, Montana-Dakota has a contract, expiring in July 2035, with WBI Energy Transmission to provide firm storage services to facilitate meeting Montana-Dakota's winter peak requirements.

The non-regulated business of this segment competes for existing customers in the areas in which it operates. Its focus on customer service and the variety of services it offers serve to enhance its competitive position.

WBI Energy is not dependent on any single customer or group of customers for sales of its products and services, where the loss of which would have a material adverse effect on its business. WBI Energy had one third-party customer that accounted for approximately 16 percent of its 2024 revenue.

Environmental MattersThe pipeline operations are subject to federal, state and local environmental, facility-siting, zoning and planning laws and regulations.

Administration of certain provisions of federal environmental laws is delegated to the states where WBI Energy and its subsidiaries operate. Administering agencies may issue permits with varying terms and operational compliance conditions. Permits are renewed and modified, as necessary, based on defined permit expiration dates, operational demand, facility upgrades or modifications, and/or regulatory changes. The pipeline operations strive to be in compliance with these regulations.

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Detailed environmental assessments and/or environmental impact statements as required by the National Environmental Policy Act are included in the FERC's environmental review process for both the construction and abandonment of WBI Energy Transmission's natural gas transmission pipelines, compressor stations and storage facilities.

In 2024, the EPA published several final rules related to GHG emissions from the oil and natural gas industry. These rules update, strengthen and expand standards to reduce GHG emissions and other air pollutants from new and existing oil and gas facilities, revise the GHG reporting rules to improve the monitoring, measurement, calculation and reporting of GHG data, and incorporate the Waste Emissions Charge provisions from the IRA. The Company continues to monitor and assess these rulemakings and the potential impacts they may have on its business processes, current and future projects, results of operations and disclosures.

The pipeline operations did not incur any material capital expenditures related to compliance with current environmental laws and regulations in 2024 and have no planned capital expenditures to meet compliance requirements of environmental laws and regulations in 2025. Capital expenditures to meet requirements of the EPA rules, as previously discussed, are included in the capital expenditures for 2026 and 2027 with estimated expenditures of $4.0 million each year. For more information on the capital expenditures for this segment, see Item 7 - MD&A - Capital Expenditures.

Discontinued Operations

General Discontinued operations includes the historical operations of Knife River and Everus, as well as associated strategic initiative costs and interest on certain third party debt facilities repaid in connection with the Knife River and Everus separations. The Company completed the separations of Knife River and Everus on May 31, 2023 and October 31, 2024, respectively. Discontinued operations also includes the supporting activities of Fidelity other than certain general and administrative costs and interest expense. For more information on discontinued operations, see Item 8 - Note 3.

Item 1A. Risk Factors

The Company's business and financial results are subject to a number of risks and uncertainties, including those set forth below and in other documents filed with the SEC. The factors and other matters discussed herein are important factors that could cause actual results or outcomes for the Company to differ materially from those discussed in the forward-looking statements included elsewhere in this document. If any of the risks described below actually occur, the Company's business, prospects, financial condition or financial results could be materially harmed. The following are the most material risk factors applicable to the Company and are not necessarily listed in order of importance or probability of occurrence.

Economic Risks

The Company is subject to government regulations that may have a negative impact on its business and its results of operations and cash flows. Statutory and regulatory requirements also may limit another party's ability to acquire the Company or impose conditions on an acquisition of or by the Company.

The Company's businesses are subject to comprehensive regulation by federal, state and local regulatory agencies with respect to, among other things, allowed rates of return and recovery of investments and costs; financing; rate structures; customer service; health care coverage and costs; taxes; franchises; recovery of fuel, purchased power and purchased natural gas costs; and construction and siting of generation and transmission facilities. These governmental regulations significantly influence the Company's operating environment and may affect its ability to recover costs from its customers. The Company is unable to predict the impact on operating results from future regulatory activities of any of these agencies. Changes in regulations or the imposition of additional regulations could have an adverse impact on the Company's results of operations and cash flows.

There can be no assurance that applicable regulatory commissions will determine that the Company's costs have been prudent, which could result in the disallowance of costs in setting rates for customers. Also, the regulatory process of approving rates for these businesses may not allow for timely and full recovery of the costs of providing services or a return on the Company's invested capital. Changes in regulatory requirements or operating conditions may require early retirement of certain assets. While regulation typically provides rate recovery for these retirements, there is no assurance regulators will allow full recovery of all remaining costs, which could leave stranded asset costs. Rising fuel costs could increase the risk that the utility businesses will not be able to fully recover those fuel costs from customers.

Approval from federal and state regulatory agencies would be needed for acquisition of the Company, as well as for certain acquisitions by the Company. The approval process could be lengthy and the outcome uncertain, which may deter potential acquirers from approaching the Company or impact the Company's ability to pursue acquisitions.

Economic volatility affects the Company's operations, as well as the demand for its products and services.

Economic conditions and population growth affect the electric and natural gas distribution businesses' growth in service territory, customer base and usage demand. Economic volatility in the markets served, along with economic conditions such as increased unemployment which could impact the ability of the Company's customers to make payments, could adversely affect the Company's results of operations, cash flows and asset values. Further, any material decreases in customers' energy demand, for economic or other reasons, could have an adverse impact on the Company's earnings and results of operations.

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The Company's operations involve risks that may result from catastrophic events.

The Company's operations include a variety of inherent hazards and operating risks, such as product leaks; explosions; mechanical failures; vandalism; fires; wildfires; pandemics; social or civil unrest; protests and riots; natural disasters; cyberattacks; acts of terrorism; and acts of war. These hazards and operating risks may occur in the future, which could result in loss of human life; personal injury; property damage; environmental impacts; impairment of operations; and substantial financial losses. The Company maintains insurance against some, but not all, of these risks and losses. A significant incident could also increase regulatory scrutiny and result in penalties and higher amounts of capital expenditures and operational costs. Losses not fully covered by insurance could have an adverse effect on the Company’s financial position, results of operations and cash flows.

A disruption of the regional electric transmission grid, local distribution infrastructure or interstate natural gas infrastructure could negatively impact the Company's business and reputation. There have been cyber and physical attacks within the energy industry on energy infrastructure, such as substations, and such attacks may occur in the future. Because the Company's electric and natural gas utility and pipeline systems are part of larger interconnecting systems, any attacks on the interconnected systems or the Company's infrastructure causing a disruption could result in a significant decrease in revenues and an increase in system repair costs negatively impacting the Company's financial position, results of operations and cash flows.

The Company’s insurance policies have limits and exclusions that may not fully mitigate losses, and an increase in cost, or the unavailability or cancellation of third-party insurance coverages, would increase the Company’s overall risk exposure.

The Company maintains insurance coverages from third party insurers as part of its overall risk management strategy and most of its customer contracts require the Company to maintain specific insurance coverage limits. The Company maintains insurance policies with respect to workers’ compensation, auto liability, general liability, excess liability, contractors pollution liability, legal liability, professional liability, directors and officers liability, employment practices liability, cyber policy, terrorism, property and other types of coverages, but these policies are subject to deductibles and the Company is self-insured up to the amount of those deductibles. Insurance losses are accrued based upon the Company's estimates of the ultimate liability for claims reported and an estimate of claims incurred but not yet reported. Insurance liabilities are difficult to assess and estimate due to unknown factors, including the frequency and severity of injuries, the magnitude of damage to or loss of property or the environment, the determination of the Company's liability in proportion to other parties, estimates of incidents not reported and the effectiveness of the Company's safety programs, and as a result, the Company's actual losses may exceed its estimates. There can be no assurance that the Company's current or past insurance coverages will be sufficient or effective under all circumstances or against all claims and liabilities, including claims resulting from wildfires or other natural disasters, to which the Company may be subject.

The Company generally renews its insurance policies on an annual basis; therefore, deductibles and levels of insurance coverages may change in future periods. There can be no assurance that any of the Company's existing insurance coverages will be renewed upon the expiration of the coverage period or that future coverage will be available at reasonable and competitive rates or at the required limits. The cost of the Company's insurance has significantly increased over time and may continue to increase in the future. In addition, insurers may fail, cancel the Company's coverage, increase the cost of coverage, determine to exclude certain items from coverage, or otherwise be unable to provide the Company with adequate insurance coverage. The Company may not be able to obtain certain types of insurance or incremental levels of insurance in scope or amount sufficient to cover liabilities it may incur. For example, due to the increase in wildfire losses and related insurance claims, insurers have reduced coverage availability and increased the cost of insurance coverage for such events in recent years, and the Company's current levels of coverage may not be sufficient to cover potential losses. If the Company's risk exposure increases as a result of adverse changes in its insurance coverage, the Company could be subject to increased liabilities that could negatively affect its business, financial condition, results of operations and cash flows.

In addition, the Company performs work in hazardous environments and its employees are exposed to a number of hazards. Incidents can occur, regardless of fault, that may be catastrophic and adversely impact the Company's employees and third parties by causing serious personal injury, loss of life, damage to property or the environment, and interruption of operations. In locations or environments where claims have become more frequent or severe in recent years, insurance may become difficult or impossible to obtain. The Company's contracts may require it to indemnify its customers, project owners and other parties for injury, damage or loss arising out of the Company's presence at its customers’ location, or in the performance of the Company's work, in both cases regardless of fault, and provide for warranties of materials and workmanship. The Company also may be required to name the customer and others as an additional insured party under its insurance policies. The Company maintains limited insurance coverage against these and other risks associated with its business. This insurance may not protect the Company against liability for certain events, and the Company cannot guarantee that its insurance will be adequate in risk coverage or policy limits to cover all losses or liabilities that it may incur. Any future damages caused by the Company's services that are not covered by insurance or are in excess of policy limits could negatively affect its business, financial condition, results of operations and cash flows.

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The Company is subject to capital market, debt and interest rate risks.

The Company's operations require significant capital investment. Consequently, the Company relies on financing sources and capital markets as sources of liquidity for capital requirements not satisfied by cash flows from operations. If the Company is not able to access capital at competitive rates, the ability to implement business plans, make capital expenditures or pursue acquisitions the Company would otherwise rely on for future growth may be adversely affected. Market disruptions may increase the cost of borrowing or adversely affect the Company's ability to access one or more financial markets. Such disruptions could include items such as a significant economic downturn, the financial distress of unrelated industry leaders in the same line of business, the deterioration of capital market conditions, turmoil in the financial services industry, volatility in commodity prices, increased trade tariffs and trade disputes with other countries, supply chain weaknesses, pandemics, natural disasters, war, terrorist attacks and cyberattacks.

The Company’s inability to generate sufficient cash flow to satisfy or refinance its debt obligations could adversely affect its business, financial condition, results of operations, and other corporate requirements. This could require the Company to direct a substantial portion of its future cash flow toward payments on its indebtedness, which would reduce the amount of cash flow available to fund working capital, capital expenditures, and other corporate requirements, thereby limiting its ability to respond to business opportunities.

If the Company does not comply with its financial covenants and does not obtain a waiver or amendment from its lenders, the lenders may elect to cause any amounts then owed to become immediately due and payable, not fund any new borrowing, or they may decline to renew the Company’s credit facility. In that event, the Company would seek to establish a replacement credit facility with one or more other lenders, including lenders with which it has an existing relationship, potentially on less desirable terms. There can be no guarantee that replacement financing would be available at commercially reasonable terms, if at all. Higher interest rates on borrowings have impacted and could further impact the Company's future operating results.

The issuance of a substantial amount of the Company's common stock, whether issued in connection with an acquisition or otherwise, would have a dilutive effect on stockholders, and such an issuance, or perception that such an issuance may occur, could adversely affect the market price of the Company's common stock.

The Company's stock price may be volatile and the value of its common stock may decline.

The market price of the Company’s common stock may be volatile and may fluctuate or decline as a result of a variety of factors, some of which are beyond its control, including without limitation actual or anticipated fluctuations in its financial condition or results of operations; variance in its financial performance from the expectations of securities analysts which may result in securities analysts issuing unfavorable research about the Company; changes in the Company’s projected operating and financial results; significant data breaches; material litigation; future sales of the Company’s common stock by the Company or its stockholders, or the perception that such sales may occur; changes in senior management or key personnel; the trading volume of the Company’s common stock; changes in the anticipated future size and growth rate of its service territories; and general macroeconomic, geopolitical, and market conditions beyond the Company’s control.

Broad market and industry fluctuations, as well as general economic, political, regulatory, and market conditions, such as recessions, or interest rate changes, may also negatively affect the market price of the Company’s common stock. In the past, companies that have experienced volatility in the market price of their securities have been subject to securities class action litigation. The Company may be the target of this type of litigation in the future, which could result in substantial expenses and divert management’s attention.

Significant changes in prices for commodities, labor or other production and delivery inputs and other environmental compliance costs could negatively affect the Company's businesses.

The Company's operations are exposed to fluctuations in prices for labor, petroleum products, raw materials and services. Prices are generally subject to change in response to fluctuations in supply and demand and other general economic and market conditions beyond the Company's control.

Fluctuations in oil and natural gas production, supplies and prices; fluctuations in commodity price basis differentials; political and economic conditions in oil-producing countries; actions of the Organization of Petroleum Exporting Countries; demand for oil due to economic conditions; war and other external factors impact the development of oil and natural gas supplies and the expansion and operation of natural gas pipeline systems. The Company has benefited from associated natural gas production in the Bakken, which has provided opportunities for organic growth projects. Depressed oil and natural gas prices; however, place pressure on the ability of oil exploration and production companies to meet credit requirements and can be a challenge if prices remain depressed long-term. Prolonged depressed prices for oil and natural gas could negatively affect the growth, results of operations, cash flows and asset values of the Company's electric, natural gas and pipeline businesses.

If oil and natural gas prices increase significantly, which has occurred and may reoccur, customer demand could decline for utility and pipeline services, which could impact the Company's results of operations and cash flows. While the Company has fuel clause recovery mechanisms for its utility operations in all of the states where it operates, higher utility fuel costs could also significantly impact results of operations if such costs are not recovered. Delays in the collection of utility fuel cost recoveries, as compared to expenditures for fuel purchases, could also negatively impact the Company's cash flows.

Increased labor costs, due to labor shortages, competition from other industries, or other factors, could negatively affect the Company's results of operations.

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In 2024, 2023 and 2022, the Company experienced elevated commodity and supply chain costs including the costs of labor, raw materials, energy-related products and other inputs used in the production and distribution of its products and services.

If environmental compliance costs increase significantly, customer demand could decline for the natural gas distribution segment, which could impact the Company’s results of operations and cash flows. While the Company has environmental compliance recovery mechanisms, higher costs could also significantly impact results of operations if such costs are not recovered. Delays in the collection of environmental compliance costs, as compared to expenditures for environmental compliance costs, could also negatively impact the Company’s cash flows.

The Company's operations could be negatively impacted by import tariffs and/or other government mandates.

The Company operates in or provides services to capital intensive industries in which federal trade policies could significantly impact the availability and cost of materials. Imposed and proposed tariffs could significantly increase the prices and delivery lead times on raw materials and finished products that are critical to the Company and its customers. Prolonged lead times on the delivery of raw materials and further tariff increases on raw materials and finished products could adversely affect the Company's business, financial condition and results of operations.

Reductions in the Company's credit ratings could increase financing costs.

There is no assurance the Company's current credit ratings, or those of its subsidiaries, will remain in effect or that a rating will not be lowered or withdrawn by a rating agency. Events affecting the Company's financial results may impact its cash flows and credit metrics, potentially resulting in a change in the Company's credit ratings. The Company's credit ratings may also change as a result of the differing methodologies or changes in the methodologies used by the rating agencies.

Increasing costs associated with health care plans and changes in employment laws or regulations may adversely affect the Company's results of operations.

The Company's self-insured costs of health care benefits for eligible employees continues to increase. Increasing quantities of large individual health care claims and an overall increase in total health care claims could have an adverse impact on operating results, financial position and liquidity. Complying with any new legislation and regulation at both the federal and state level related to health care, unemployment tax rates and workers' compensation rates, among others, could adversely affect the Company's results of operations as well change the Company's benefit program and costs.

The Company is exposed to risk of loss resulting from the nonpayment and/or nonperformance by the Company's customers and counterparties.

If the Company's customers or counterparties experience financial difficulties, which has occurred and may reoccur in the future, the Company could experience difficulty in collecting receivables. Nonpayment and/or nonperformance by the Company's customers and counterparties, particularly customers and counterparties of the Company’s pipeline business, could have a negative impact on the Company's results of operations and cash flows. The Company could also have indirect credit risk from participating in energy markets such as MISO in which credit losses are socialized to all participants.

Changes in tax law and other regulations may negatively affect the Company's business.

Changes to federal, state and local tax laws have the ability to benefit or adversely affect the Company's earnings and customer costs. Significant changes to corporate tax rates could result in the impairment of deferred tax assets that are established based on existing law at the time of deferral. The U.S. administration has introduced uncertainty regarding the continuation of the IRA and a potential shift in federal energy policies regarding clean energy projects. Changes in regulations that impact the value of various tax credits, including production tax credits could change the economics of resources and the resource selection could impact current and/or future projects for the electric generation business and the development of other renewable energy projects, such as RNG. Such actions could adversely affect the Company's ability to secure tax credits and other incentives that support the development of renewable energy projects. Regulation incorporates changes in tax law into the rate-setting process, which could create timing delays before the impact of changes are realized.

Financial market changes could impact the Company’s pension and postretirement benefit plans and obligations.

The Company has pension and postretirement defined benefit plans for some of its current and former employees. Assumptions regarding future costs, returns on investments, interest rates and other actuarial assumptions have a significant impact on the funding requirements and expense recorded relating to these plans. Adverse changes in economic indicators, such as consumer spending, inflation data, interest rate changes, political developments and threats of terrorism, among other things, can create volatility in the financial markets. These changes could impact the assumptions and negatively affect the value of assets held in the Company's pension and other postretirement benefit plans and may increase the amount and accelerate the timing of required funding contributions for those plans.

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Operational Risks

Significant portions of the Company’s natural gas pipelines and power generation and transmission facilities are aging. The aging infrastructure may require significant additional maintenance or replacement that could adversely affect the Company’s results of operations.

Certain risks increase as the Company's energy delivery infrastructure ages, including breakdown or failure of equipment, pipeline leaks and fires developing from power lines, all of which have occurred and may reoccur in the future resulting in material costs. Aging infrastructure is more prone to failure, which increases maintenance costs, unplanned outages and the need to replace facilities. Even if properly maintained, reliability may ultimately deteriorate and negatively affect the Company’s ability to serve its customers, which could result in increased costs associated with regulatory oversight. The costs associated with compliance with PHMSA rules related to pipeline integrity and other similar programs, maintaining the aging infrastructure and capital expenditures for new or replacement infrastructure could cause rate volatility and/or regulatory lag in some jurisdictions. If, at the end of its life, the investment costs of a facility have not been fully recovered, the Company may be adversely affected if commissions do not allow such costs to be recovered in rates. Such impacts of aging infrastructure could adversely affect the Company’s results of operations and cash flows.

Additionally, hazards from aging infrastructure could result in serious injury, loss of human life, significant damage to property, environmental impacts and impairment of operations, which in turn could lead to substantial financial losses. The location of facilities near populated areas, including residential areas, business centers, industrial sites and other public gathering places, could increase the damages resulting from these risks. A major incident involving another natural gas system could lead to additional capital expenditures, increased regulation, and fines and penalties on natural gas utilities and pipelines. The occurrence of any of these events could adversely affect the Company’s results of operations, financial position and cash flows.

The Company's utility and pipeline operations are subject to planning risks.

Most electric and natural gas utility investments, including natural gas transmission pipeline investments, are made with the intent of being used for decades. In particular, electric transmission and generation resources are planned well in advance of when they are placed into service based upon resource plans using assumptions over the planning horizon, including sales growth, commodity prices, equipment and construction costs, regulatory treatment, available technology and public policy. Public policy changes and technology advancements related to areas, such as energy efficient appliances and buildings, renewable and distributive electric generation and storage, carbon dioxide emissions, electric vehicle penetration, restrictions on or disallowance of new or existing services, and natural gas availability and cost may significantly impact the planning assumptions. Changes in critical planning assumptions may result in excess generation, transmission and distribution resources creating increased per customer costs and downward pressure on load growth. These changes could also result in a stranded investment if the Company is unable to fully recover the costs of its investments.

The Company's inability to implement its long-term strategic plan may adversely affect future results.

The Company’s ability to successfully implement and execute its long-term strategic plan is dependent on many factors. The Company’s strategies may require significant capital investment and management attention. If the Company cannot successfully execute its strategic growth initiatives or if the long-term plan does not adequately address the challenges or opportunities the Company faces, its financial condition and results of operations may be adversely affected. Additionally, failure to meet stockholder expectations, particularly with respect to financials, cost-cutting programs, operating margins, and earnings per share, could result in volatility in the market value of the Company’s stock.

The regulatory approval, permitting, construction, startup and/or operation of pipelines, power generation and transmission facilities may involve unanticipated events, delays and unrecoverable costs.

The construction, startup and operation of natural gas pipelines and electric power generation and transmission facilities involve many risks, which may include delays; breakdown or failure of equipment; inability to obtain required governmental permits and approvals; inability to obtain or renew easements; public opposition; inability to complete financing; inability to negotiate acceptable equipment acquisition, construction, fuel supply, off-take, transmission, transportation or other material agreements; contractor performance failures; changes in markets and market prices for power; cost increases and overruns; the risk of performance below expected levels of output or efficiency; and the inability to obtain full cost recovery in regulated rates. Such unanticipated events could negatively impact the Company's business, its results of operations and cash flows.

Operating or other costs required to comply with current or potential pipeline safety regulations and potential new regulations under various agencies could be significant. The regulations require verification of pipeline infrastructure records by pipeline owners and operators to confirm the maximum allowable operating pressure of certain lines. Increased emphasis on pipeline safety and increased regulatory scrutiny may result in penalties and higher costs of operations. If these costs are not fully recoverable from customers, they could have an adverse effect on the Company’s results of operations and cash flows.

Supply chain disruptions may adversely affect Company operations.

The Company relies on third-party vendors and manufacturers to supply many of the materials necessary for its operations. Global logistic disruptions have impacted the flow of materials and restricted global trade flows. Manufacturers are competing for a limited supply of key commodities and logistical capacity which has impacted lead times, pricing, supply and demand. Disruptions or delays in receiving materials; price increases from suppliers or manufacturers; or inability to source needed materials, which have occurred and could reoccur, could adversely affect the Company’s capital expenditure programs, results of operations, financial condition and cash flows.

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Joint ownership of coal-fired generation facilities could impact the Company’s ability to manage changing regulations and economic conditions.

The Company has an ownership interest in three coal-fired electric generating facilities jointly with other co-owners who have varying ownership interests in the facilities. The Company’s ability to make determinations on changing environmental regulations and economic conditions may be impacted by its rights and obligations under the co-ownership agreements and related agreements. Such a determination could impact the Company’s ability to effectively manage these changing conditions to meet its strategic objectives and could adversely impact its financial condition, results of operations and liquidity.

Environmental and Regulatory Risks

The Company's operations could be adversely impacted by severe weather.

Severe weather events, such as tornadoes, fires, rain, drought, ice and snowstorms, and high and low temperature extremes, occur in regions in which the Company operates and maintains infrastructure. Climate change could change the frequency and severity of these weather events, which may create physical and financial risks to the Company. Such risks could have an adverse effect on the Company's financial condition, results of operations and cash flows.

Severe weather events may damage or disrupt the Company's electric and natural gas transmission and distribution facilities, which could result in disruption of service and ability to meet customer demand and increase maintenance or capital costs to repair facilities and restore customer service. The cost of providing service could increase if the frequency of severe weather events increases because of climate change or otherwise. The Company may not recover all costs related to mitigating these physical risks.

Utility customers’ energy needs vary with weather conditions, primarily temperature and humidity. For residential customers, heating and cooling represent the largest energy use. To the extent weather conditions are affected by climate change, customers’ energy use could increase or decrease. Increased energy use by its utility customers due to weather may require the Company to invest in additional generating assets, transmission and other infrastructure to serve increased load. Decreased energy use due to weather may result in decreased revenues. Extreme weather conditions, such as uncommonly long periods of high or low ambient temperature in general require more system backup, adding to costs, and can contribute to increased system stress, including service interruptions. Weather conditions outside of the Company's service territory could also have an impact on revenues. The Company buys and sells electricity that might be generated outside its service territory, depending upon system needs and market opportunities. Extreme temperatures may create high energy demand and raise electricity prices, which could increase the cost of energy provided to customers.

Climate change may impact a region’s economic health, which could impact revenues at all of the Company's businesses. The Company's financial performance is tied to the health of the regional economies served. The Company provides natural gas and electric utility service for some states and communities that are economically affected by the agriculture industry. Increases in severe weather events or significant changes in temperature and precipitation patterns could adversely affect the agriculture industry and, correspondingly, the economies of the states and communities affected by that industry.

The insurance industry may be adversely affected by severe weather events, which may impact availability of insurance coverage, insurance premiums and insurance policy terms.

The Company may be subject to litigation related to climate change. Costs of such litigation could be significant, and an adverse outcome could require substantial capital expenditures, changes in operations and possible payment of penalties or damages, which could affect the Company's results of operations and cash flows if the costs are not recoverable in rates.

The price of energy also has an impact on the economic health of communities. The cost of additional regulatory requirements related to climate change, such as regulation of carbon dioxide emissions under the federal Clean Air Act, requirements to replace fossil fuels with renewable energy or credits, or other environmental regulation or taxes, could impact the availability of goods and the prices charged by suppliers, which would normally be borne by consumers through higher prices for energy and purchased goods, and could adversely impact economic conditions of areas served by the Company. To the extent financial markets view climate change and emissions of GHGs as a financial risk, this could negatively affect the Company's ability to access capital markets or result in less competitive terms and conditions.

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The Company's operations are subject to environmental laws and regulations that may increase costs of operations, impact or limit business plans, or expose the Company to environmental liabilities.

The Company is subject to environmental laws and regulations affecting many aspects of its operations, including air and water quality, wastewater discharge, the generation, transmission and disposal of solid waste and hazardous substances, and other environmental considerations. These laws and regulations can increase capital, operating and other costs; cause delays as a result of litigation and administrative proceedings; and create compliance, remediation, containment, monitoring and reporting obligations. Environmental laws and regulations can also require the Company to install pollution control equipment at its facilities, clean up spills and other contamination and correct environmental hazards, including payment of all or part of the cost to remediate sites where the Company's past activities, or the activities of other parties, caused environmental contamination. These laws and regulations generally require the Company to obtain and comply with a variety of environmental licenses, permits, inspections and other approvals and may cause the Company to shut down existing facilities due to difficulties in assuring compliance or where the cost of compliance makes operation of the facilities uneconomical. Although the Company strives to comply with all applicable environmental laws and regulations, public and private entities and private individuals may interpret the Company's legal or regulatory requirements differently and seek injunctive relief or other remedies against the Company. The Company cannot predict the outcome, financial or operational, of any such litigation or administrative proceedings.

Existing environmental laws and regulations may be revised and new laws and regulations seeking to protect the environment have been adopted such as the Climate Commitment Act in Washington and the Climate Protection Program Rule in Oregon, requiring natural gas distribution companies to reduce overall GHG emissions, and the EPA's Coal Combustion Residuals Rule, potentially requiring additional management and remediation of electric generation coal ash facilities, and other future rules may be adopted or become applicable to the Company. These laws and other regulations could require the Company to limit the use or output of certain facilities; restrict the use of certain fuels; prohibit or restrict new or existing services; replace certain fuels with renewable fuels; retire and replace certain facilities; install pollution controls; remediate environmental impacts; remove or reduce environmental hazards; or forego or limit the development of resources. Revised or new laws and regulations that increase compliance and disclosure costs and/or restrict operations, particularly if costs are not fully recoverable from customers, could adversely affect the Company's results of operations and cash flows.

Stakeholder actions and increased regulatory activity related to ESG matters, particularly climate change and reducing GHG emissions, could adversely impact the Company's operations, costs of or access to capital and impact or limit business plans.

The Company has faced and may continue to face stakeholder scrutiny related to ESG matters. Certain stakeholders of the Company, such as investors, customers, employees and lenders, have increased their scrutiny of the impacts and social cost associated with ESG matters, including climate change. Concern that GHG emissions contribute to global climate change has led to international, federal, state and local legislative and regulatory proposals to reduce or mitigate the effects of GHG emissions. The Company may experience significant future costs associated with compliance of such legislative actions. The Company’s primary GHG emission is carbon dioxide from fossil fuels combustion at Montana-Dakota's electric generating facilities, particularly its jointly owned coal-fired facilities.

Treaties, legislation or regulations to reduce GHG emissions in response to climate change may be adopted and can affect the Company's operations by requiring additional energy conservation efforts or renewable energy sources, limiting emissions, imposing carbon taxes or other compliance costs; as well as other mandates that could significantly increase capital expenditures and operating costs or reduce demand for the Company's services. If the Company’s utility and pipeline operations do not receive timely and full recovery of GHG emission compliance costs from customers, then such costs could adversely impact the results of operations and cash flows. Significant reductions in demand for the Company's services as a result of increased costs or emissions limitations could also adversely impact the results of operations and cash flows.

Due to the uncertain availability of technologies to control GHG emissions and the unknown obligations that potential GHG emission legislation or regulations may create, the Company cannot determine the potential financial impact on its operations. In addition, any increased focus on climate change and stricter regulatory requirements may result in the Company facing adverse reputational risks associated with certain of its operations producing GHG emissions. There have also been efforts to discourage the investment community from investing in equity and debt securities of companies engaged in fossil fuel related business and pressuring lenders to limit funding to such companies. Additionally, some insurance carriers have indicated an unwillingness to insure assets and operations related to certain fossil fuels. If the Company is unable to satisfy the climate-related expectations of certain stakeholders, the Company may suffer reputational harm, which may cause its stock price to decrease or difficulty in accessing the capital or insurance markets. Such efforts, if successfully directed at the Company, could increase the costs of or access to capital or insurance and interfere with business operations and ability to make capital expenditures.

Other Risks

The Company's businesses are seasonal and subject to weather conditions that could adversely affect the Company's operations, revenues and cash flows.

The Company's results of operations could be affected by changes in the weather. Weather conditions influence the demand for electricity and natural gas and affect the price of energy commodities. Utility operations have historically generated lower revenues when weather conditions are cooler than normal in the summer and warmer than normal in the winter, particularly in jurisdictions that do not have weather normalization mechanisms in place. Where weather normalization mechanisms are in place, there is no assurance the Company will continue to receive such regulatory protection from adverse weather in future rates.

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Adverse weather conditions, which have occurred and may reoccur, such as heavy or sustained rainfall or snowfall, droughts, storms, wind and colder weather may affect ongoing operation and maintenance and construction activities for the electric and natural gas transmission and distribution businesses. In addition, severe weather can be destructive, causing outages and property damage, which could require additional remediation costs. As a result, unusual or adverse weather conditions could negatively affect the Company's results of operations, financial position and cash flows.

Competition exists in all of the Company's businesses.

The Company's businesses are subject to competition. The electric utility and natural gas businesses also experience competitive pressures as a result of consumer demands, technological advances and other factors. The pipeline business competes with several pipelines for access to natural gas supplies and for transportation and storage business. New acquisition opportunities are subject to competitive bidding environments which impact prices the Company must pay to successfully acquire new properties and acquisition opportunities to grow its business. The Company's failure to effectively compete could negatively affect the Company's results of operations, financial position and cash flows.

The Company's operations may be negatively affected if it is unable to obtain, develop and retain key personnel and skilled labor forces.

The Company must attract, develop and retain executive officers and other professional, technical and skilled labor forces with the skills and experience necessary to successfully manage, operate and grow the Company's businesses.

Due to the changing workforce dynamics and an insufficient number of qualified applicants to replace skilled employees as they retire and remote work opportunities, among other things, competition for these employees is high. In some cases competition for these employees is on a regional or national basis. At times of low unemployment, it can be difficult for the Company to attract and retain qualified and affordable personnel. A shortage in the supply of personnel creates competitive hiring markets, increased labor expenses, decreased productivity and potentially lost business opportunities to support the Company's operating and growth strategies. The Company is subject to risks associated with labor disputes or prolonged negotiation processes, which could disrupt operations and increase costs. Additionally, if the Company is unable to hire employees with the requisite skills, the Company may be forced to incur significant training expenses. As a result, the Company's ability to maintain productivity, relationships with customers, competitive costs, and quality services is limited by the ability to employ, retain and train the necessary personnel and could negatively affect the Company's results of operations, financial position and cash flows.

The Company is a holding company and relies on cash from its subsidiaries to pay dividends.

The Company depends on earnings, cash flows and dividends from its subsidiaries to pay dividends on its common stock. Regulatory, contractual and legal limitations, as well as their capital requirements, affect the ability of the subsidiaries to pay dividends to the Company and thereby could restrict or influence the Company's ability or decision to pay dividends on its common stock, which could adversely affect the Company's stock price.

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Costs related to obligations under a MEPP could have a material negative effect on the Company's results of operations and cash flows.

An operating subsidiary of the Company participates in a MEPP for employees represented by a union. The Company is required to make contributions to this plan in amounts established under the collective bargaining agreement between the operating subsidiary and the union. The Company may be obligated to increase its contribution to the plan if it becomes underfunded and is classified as being in endangered, seriously endangered or critical status as defined by the Pension Protection Act of 2006, or if other participating employers withdraw from the plan and are unable to contribute sufficient amounts. The amount and timing of any increase in the Company's required contributions may depend upon one or more factors, including the outcome of collective bargaining; actions taken by the trustee; actions taken by the plan's other participating employers; the industry; future determinations of plan status; and laws and regulations. The Company could experience increased operating expenses as a result of required contributions to the MEPP, which could have an adverse effect on the Company's results of operations, financial position or cash flows. In addition, pursuant to ERISA, as amended by MPPAA, the Company could incur a partial or complete withdrawal liability upon withdrawing from the plan, exiting a market in which it does business with a union workforce or upon termination of a plan. The Company could also incur an additional withdrawal liability if its withdrawal from the plan is determined by that plan to be part of a mass withdrawal.

The Company may face risks associated with stockholder activism.

Publicly-traded companies are subject to campaigns by stockholders advocating corporate actions related to matters, such as corporate governance, operational practices, and strategic direction. The Company has, and may again in the future, become subject in the future to such stockholder activity and demands. Such activities could interfere with its ability to execute its business plans, affect the allocation of capital, be costly and time-consuming, disrupt operations, and divert the attention of management, any of which could have an adverse effect on the Company’s business or stock price.

Technology disruptions or cyberattacks could adversely impact the Company's operations.

The Company uses technology in substantially all aspects of its business operations and requires uninterrupted operation of information technology and operation technology systems, including disaster recovery and backup systems and network infrastructure. These systems may be vulnerable to physical and cybersecurity failures or unauthorized access, due to hacking, human error, theft, sabotage, malicious software, ransomware, third-party compromise, acts of terrorism, acts of war, acts of nature or other causes.

Should a compromise or system failure occur, interdependencies to technology may disrupt the Company's ability to fulfill critical business functions. This may include interruption of electric generation, transmission and distribution facilities, natural gas storage and pipeline facilities, any of which could adversely affect the Company's reputation, business, cash flows and results of operations or subject the Company to legal or regulatory liabilities and increased costs. Litigation expenses and damages for such an event can be significant. Additionally, the Company's electric generation and transmission systems and natural gas pipelines are part of interconnected systems with other operators’ facilities; therefore, a cyber-related disruption in another operator’s system could negatively impact the Company's business.

The Company’s accounting systems and its ability to collect information and invoice customers for products and services could be disrupted. If the Company’s operations are disrupted, it could result in decreased revenues and remediation costs that could adversely affect the Company's results of operations and cash flows.

The Company is subject to cybersecurity and privacy laws, regulations and security directives of many government agencies, including TSA, FERC and NERC. NERC issues comprehensive regulations and standards surrounding the security of bulk power systems and continually updates these requirements, as well as establishing new requirements with which the utility industry must comply. As these regulations evolve, the Company may experience increased compliance costs and may be at higher risk for violating these standards. Experiencing a cybersecurity incident could cause the Company to be non-compliant with applicable laws and regulations, causing the Company to incur costs related to legal claims, proceedings and regulatory fines or penalties. The SEC has adopted rules that require the Company to provide disclosures around cybersecurity risk management, strategy, and governance, as well as disclose the occurrence of material cybersecurity incidents. These rules may also require the Company to report a cybersecurity incident before the Company has been able to fully assess its impact or remediate the underlying issue. Efforts to comply with such reporting requirements could divert management's attention from the Company's incident response and could potentially reveal system vulnerabilities to threat actors. Failure to timely report incidents under these or other similar rules could also result in monetary fines, sanctions or subject the Company to other forms of liability. This regulatory environment is increasingly challenging and may present material obligations and risks to the Company's business, including significantly expanded compliance burdens, costs, and enforcement risks.

The Company, through the ordinary course of business, requires access to sensitive customer, supplier, employee and Company data. A breach of the Company's systems could compromise sensitive data and could go unnoticed for some time. Such an event could result in negative publicity and reputational harm, remediation costs, legal claims and fines that could have an adverse effect on the Company's financial results. Third-party service providers that perform critical business functions for the Company or have access to sensitive information within the Company also may be vulnerable to security breaches and information technology risks that could adversely affect the Company.

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The Company’s information systems experience ongoing and often sophisticated cyberattacks by a variety of sources with the apparent aim to breach the Company's cyber-defenses. The Company may face increased cyber risk due to the increased use of employee-owned devices, work from home arrangements, and the separation of Everus. Such incidents could have a material adverse effect in the future as cyberattacks continue to increase in frequency and sophistication. The Company is continuously reevaluating the need to upgrade and/or replace systems and network infrastructure. These upgrades and/or replacements could adversely impact operations by imposing substantial capital expenditures, creating delays or outages, or experiencing difficulties transitioning to new systems. System disruptions, if not anticipated and appropriately mitigated, could adversely affect the Company.

Artificial intelligence presents challenges that can impact the Company's business by posing security risks to confidential or proprietary information and personal data

The use of artificial intelligence, combined with an uncertain regulatory environment, may result in reputational harm, liability, or other adverse consequences to business operations. The Company has, and may again in the future, adopt and integrate certain artificial intelligence tools into its systems for specific use cases. The Company’s vendors and third-party partners may incorporate artificial intelligence tools into their offerings with or without disclosing this use to the Company. The providers of these artificial intelligence tools may not meet existing or rapidly evolving regulatory or industry standards concerning privacy and data protection, which may result in a loss of intellectual property or confidential information and/or cause harm to the Company’s reputation and the public perception of the effectiveness of its security measures. Further, bad actors around the world use increasingly sophisticated methods, including artificial intelligence, to engage in illegal activities involving the theft and misuse of personal information, confidential information, and intellectual property. Any of these outcomes could damage the Company’s reputation, result in the loss of valuable property and information and adversely impact its business.

Pandemics may have a negative impact on the Company's business operations, revenues, results of operations, liquidity and cash flows.

Pandemics have disrupted national, state and local economies in the past and may again in the future. To the extent pandemics adversely impact the Company's businesses, operations, revenues, liquidity or cash flows, they could also have a heightened effect of other risks. The degree to which pandemics impact the Company depends on, among other things, federal, state and local mandates, actions taken by governmental authorities, availability, timing and effectiveness of vaccines being administered, and the pace and extent to which the economy recovers and operates under normal market conditions.

Separation Risks

If the completed separations of Knife River or Everus, together with certain related transactions, were to fail to qualify as transactions that are generally tax-free for U.S. federal income tax purposes, the Company and its stockholders could be subject to significant tax liabilities.

The Company completed the separations of Knife River and Everus on May 31, 2023, and October 31, 2024, respectively. In connection with the completed separations, the Company received private letter rulings from the IRS and opinion(s) of outside counsel regarding the qualification of certain elements of the separations and distributions under Section 355(a) of the Code. Notwithstanding prior receipt of IRS private letter rulings and opinion(s) of tax advisors, the IRS could determine that the completed distributions and/or certain related transactions should be treated as taxable transactions for U.S. federal income tax purposes if it determines that any of the representations, assumptions, or undertakings upon which the IRS private letter rulings or the opinion(s) of tax advisors were based are false or have been violated. In addition, neither the IRS private letter rulings nor opinion(s) of tax advisors will address all of the issues that are relevant to determining whether the distributions, together with certain related transactions, qualifies as transactions that are generally tax-free for U.S. federal income tax purposes. Further, opinion(s) of tax advisors represent the judgment of such tax advisors and are not binding on the IRS or any court, and the IRS or a court may disagree with the conclusions in the opinion(s) of tax advisors. Accordingly, notwithstanding receipt by the Company of the IRS private letter rulings and the opinion(s) of tax advisors, there can be no assurance that the IRS will not assert that the distributions and/or certain related transactions do not qualify for tax-free treatment for U.S. federal income tax purposes or that a court would not sustain such a challenge. In the event the IRS were to prevail in such challenge, the Company and its stockholders could be subject to significant U.S. federal income tax liability.

Item 1B. Unresolved Staff Comments

The Company has no unresolved comments with the SEC.

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Item 1C. Cybersecurity

Risk Management and Strategy

Overall Risk Management

The Company has implemented a cyber risk management program to help ensure that the Company's electronic information and information systems are protected from various threats. The cyber risk management program is maintained as part of the Company's overall governance, ERM program and compliance program. The Company's information systems experience ongoing and often sophisticated cyberattacks by a variety of sources with the apparent aim to breach the Company's cyber-defenses. The Company has and may continue to face increased cyber risk due to the increased use of employee-owned devices and work from home arrangements. The Company is continuously reevaluating the need to upgrade and/or replace systems and network infrastructure. These upgrades and/or replacements could adversely impact operations by imposing substantial capital expenditures, creating delays or outages, or experiencing difficulties transitioning to new systems. System disruptions, if not anticipated and appropriately mitigated, could adversely affect the Company. The Company continually assesses risks from cybersecurity threats and adapts and enhances its controls accordingly.

Risks from Cybersecurity Threats

Any risks from previous cybersecurity threats, including as a result of any previous cybersecurity incidents, have not materially affected or are reasonably likely to materially affect the Company's business, financial condition, or results of operations. Such risks and incidents could have a material adverse effect in the future as cyberattacks continue to increase in frequency and sophistication. The Company also has cyber event related insurance.

Employee Cybersecurity Training

The Company provides ongoing cybersecurity training and compliance programs to facilitate education for employees who may have access to the Company's data and critical systems. Employee phishing tests are conducted on a monthly basis.

Engage Third-parties on Risk Management

Periodic external reviews, including penetration tests and security framework assessments, are conducted by auditors, external assessors, and/or consultants to assess and ensure compliance with the Company’s information security programs and practices. Internal and external auditors assess the Company’s information technology general controls on an annual basis.

Oversee Third-party Risk

The Company has implemented a third-party management risk program to help monitor and reduce risks associated with the Company's vendors, which includes processes such as completing due diligence on third party service providers before engaging with them for their services; assessing the third party’s cybersecurity posture by reviewing audit reports of the third party, completing cyber questionnaires, and reviewing applicable certification; including cybersecurity contractual language in contracts to limit risk; and monitoring and reassessing third party’s to ensure ongoing compliance with their cybersecurity obligations.

Physical Security

The Company safeguards assets through a standard physical security design process, including access controls, surveillance and monitoring, perimeter security controls, data center security, and incident response and reporting controls.

Operational Technology

The Company has operation technology, consisting of the hardware and software that monitors and controls devices, processes, and infrastructure related to the Company's operational assets. Security protocols for the Company's operational technology follow applicable NERC, FERC and TSA regulations and security directives.

Other Risk Factors

Notwithstanding the breadth of the Company's information security program, the Company may be unsuccessful in preventing or mitigating a cybersecurity event that could have a material adverse impact. See “Item 1A – Risk Factors – Other Risks – Technology disruptions or cyberattacks could adversely impact the Company's operations.”

Governance

Board of Directors Oversight

The Company's board of directors, as a whole and through its committees, has responsibility for oversight of risk management. In its risk oversight role, the board of directors has the responsibility to satisfy itself that the risk management processes designed and implemented by management are adequate for identifying, assessing, and managing risk. The audit committee of the board of directors of the Company is responsible for oversight of risks from cybersecurity threats.

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Management's Role Managing Risk

The Company's CIO plays a large role in informing the audit committee of the board of directors on cybersecurity risks. The audit committee of the board of directors receives presentations and reports from the CIO on cybersecurity related issues which include information security, technology risks and risk mitigation programs regularly at the quarterly board meetings. In addition to scheduled meetings, the CIO and audit committee of the board of directors maintain an ongoing dialogue regarding emerging or potential cybersecurity risks.

Cybersecurity Incident Response

The Company has an incident response plan to identify, protect, detect, respond to, and recover from cybersecurity threats and incidents that is also tested on an annual basis. The incident response plan is updated based on results of the test or as new cyber related developments occur. The CIO, executive leadership which includes the chief executive officer, chief financial officer, chief accounting officer, chief legal officer, and SEC financial reporting department employees, and the board of directors are notified of any material cybersecurity incidents through a defined escalation process. The defined escalation process is a risk-based process that specifies who is to be contacted and when at each risk level.

Monitor, Manage, and Safeguard Against Cybersecurity Incidents and Risks

The Company's CIO, along with its director of cybersecurity and a designated security team of professionals, are responsible for assessing and managing risks as well as developing and implementing policies, procedures, and practices based on the range of threats faced by the Company. There are processes around access management, data security, encryption, asset management, secure system development, security operations, network and device security to provide safeguards from a cybersecurity incident along with continual monitoring of various threat intelligence feeds.

Cyber Risk Management Personnel

The Company's director of cybersecurity reports to the CIO and the CIO reports directly to the Company's chief executive officer. The Company's CIO who served as the first CIO of the Company since 2016, oversaw the information technology and cybersecurity portfolios until her retirement on January 10, 2025. A new CIO from within the Company was named to succeed the retiring CIO and holds both a bachelor's and master's degree in business administration with over 25 years of information technology experience in the energy and utilities business. The director of cybersecurity has a bachelor’s degree in computer information systems, over 25 years of information security experience, and holds certified information systems security professional and certified risk and information systems control certifications. The other members of information technology director level leadership also responsible for managing cybersecurity risks have degrees including Bachelor of Computer Information Systems, information systems management, electronics, electrical engineering, business administration, and accounting, along with certified information systems auditor certification and a cybersecurity fundamentals certificate.

Cyber Risk Oversight Committee

Additionally, in 2014 the board of directors established CyROC to provide executive management and the audit committee of the board of directors with analyses, appraisals, recommendations and pertinent information concerning cyber defense of the Company's electronic information, information technology and operation technology systems. The CyROC is responsible for guiding the Company's comprehensive cybersecurity policies and oversight of cybersecurity risks. The CyROC is chaired by the Company's CIO and is comprised of members such as the chief financial officer, information technology leaders, internal auditors, and other leaders from across the Company.

Item 3. Legal Proceedings

SEC regulations require the Company to disclose certain information about proceedings arising under federal, state or local environmental provisions if the Company reasonably believes that such proceedings may result in monetary sanctions above a stated threshold. Pursuant to SEC regulations, the Company has adopted a threshold of $1.0 million for purposes of determining whether disclosure of any such proceedings is required.

For information regarding legal proceedings required by this item, see Item 8 - Note 21, which is incorporated herein by reference.

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The Company's common stock is listed on the NYSE under the symbol "MDU."

As of February 13, 2025, the Company's common stock was held by approximately 8,700 stockholders of record.

Based on the Company becoming a pure-play regulated energy delivery business, the Company's board of directors established a long-term dividend payout ratio target of 60 percent to 70 percent of regulated energy delivery earnings. The Company has an 87-year history of uninterrupted dividend payments to stockholders and remains committed to paying a competitive dividend. The Company depends on earnings and dividends from its subsidiaries to pay dividends on common stock. The declaration and payment of dividends is at the sole discretion of the board of directors, subject to limitations imposed by agreements governing the Company's indebtedness, federal and state laws, and applicable regulatory limitations. For more information on factors that may limit the Company's ability to pay dividends, see Item 8 - Note 12.

The following table includes information with respect to the Company's purchase of equity securities:

ISSUER PURCHASES OF EQUITY SECURITIES

October 1 through October 31, 2024 — — — —

December 1 through December 31, 2024 — — — —

(1) Represents MDU original issue shares of common stock in connection with annual stock grants made to the Company's non-employee directors.

(2) Not applicable. The Company does not currently have in place any publicly announced plans or programs to repurchase equity securities.

Item 6.

Reserved.

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The Company provides essential services, delivering reliable energy that powers lives. Through its infrastructure investments and operations the Company drives economic growth, supports communities, and energizes businesses that keep America moving.

Strategic Initiatives On May 31, 2023, the Company completed the separation of Knife River, its construction materials and contracting business, resulting in Knife River becoming an independent, publicly-traded company. The Company's board of directors approved the distribution of approximately 90 percent of the issued and outstanding shares of Knife River to the Company's stockholders. Stockholders of the Company received one share of Knife River common stock for every four shares of the Company's common stock held on May 22, 2023, the record date for the distribution. The Company retained approximately 10 percent or 5.7 million shares of Knife River common stock immediately following the separation, which were disposed of in a tax-free exchange in November 2023. The separation of Knife River was a tax-free spinoff transaction to the Company's stockholders for U.S. federal income tax purposes.

On October 31, 2024, the Company completed the separation of Everus, its construction services business, resulting in Everus becoming an independent, publicly-traded company. The Company's board of directors approved the distribution of all the outstanding shares of Everus common stock to the Company's stockholders. Stockholders of the Company received one share of Everus common stock for every four shares of the Company's common stock held as of the close of business on October 21, 2024, the record date for the distribution. The separation of Everus was a tax-free spinoff transaction to the Company's stockholders for U.S. federal income tax purposes, except for cash received in lieu of fractional shares.

The Company incurred costs in connection with the strategic initiatives in 2022, 2023 and 2024, as noted in the Business Segment Financial and Operating Data section, and expects the majority of the separation costs have already been incurred.

Based on the Company becoming a pure-play regulated energy delivery business, the Company's board of directors established a long-term dividend payout ratio target of 60 percent to 70 percent of regulated energy delivery earnings. The Company has an 87-year history of uninterrupted dividend payments to stockholders and remains committed to paying a competitive dividend.

Market Trends The Company continues to manage the inflationary pressures experienced throughout the United States, including the impact that inflation, higher interest rates, commodity price volatility and supply chain disruptions may have on its business and customers and proactively looks for ways to lessen the impact to its business. The Company has observed supply chain improvements in lead times for certain commodities. Although the Company has started to see some reduction to interest rates, they remain elevated and have resulted in and may continue to result in increased borrowing costs on new debt, impacts to the Company's asset valuations and negatively impacting the purchasing power of its customers. For more information on possible impacts to the Company's businesses, see the Outlook for each segment below and Item 1A - Risk Factors.

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Consolidated Earnings Overview

The following table summarizes the contribution to the consolidated income by each of the Company's business segments.

(In millions, except per share amounts)

Earnings per share - basic:

Income from continuing operations $ .89 $ 1.62 $ .58

Discontinued operations, net of tax .49 .42 1.23

Earnings per share - basic $ 1.38 $ 2.04 $ 1.81

Earnings per share - diluted:

Income from continuing operations $ .88 $ 1.62 $ .58

Discontinued operations, net of tax .49 .41 1.23

Earnings per share - diluted $ 1.37 $ 2.03 $ 1.81

The Company completed the separations of Knife River on May 31, 2023, its former construction materials and contracting segment, and of Everus on October 31, 2024, its former construction services segment, into new independent publicly-traded companies. As a result of these separations, the historical results of operations for Knife River and Everus are shown in discontinued operations, net of tax, except for allocated general corporate overhead costs of the Company, which did not meet the criteria for discontinued operations and are reflected in Other. Also included in discontinued operations are certain strategic initiative costs associated with the separations of Knife River and Everus. Other includes activity for Everus for ten months in 2024 compared to the full year in 2023 and Knife River activity for five months in 2023 compared to the full year in 2022.

2024 compared to 2023 The Company's consolidated earnings decreased $133.6 million primarily due to the absence of the Company's 2023 gain of $186.6 million related to the tax-free exchange of its retained shares in Knife River, partially offset by increased earnings at the pipeline and electric businesses.

•The electric business experienced higher retail sales revenue due to rate relief in North Dakota, South Dakota and Montana. Lower volumes from the majority of customers, primarily due to cooler weather in the second quarter, and higher operation and maintenance expense, primarily contract services costs, partially offset the increases.

•Decreased earnings at the natural gas distribution business was largely the result of higher operation and maintenance expense, primarily higher contract services costs, higher payroll-related costs, and higher software expenses. Also decreasing net income was higher depreciation and amortization expense, primarily due to increased asset additions. These decreases were partially offset by higher retail sales revenue, primarily due to rate relief in North Dakota and South Dakota.

•The pipeline's earnings increase was driven by higher transportation volumes, primarily from growth projects placed in service in November 2023 and throughout 2024 and increased contracted volume commitments beginning February 2023. Higher storage-related revenue and a full year of new transportation and storage service rates in 2024 further drove the increase. The business also benefited from proceeds received from a customer settlement that was recorded in other income and a decrease in the Company's effective state income tax rate. The increase was offset in part by higher operation and maintenance expense primarily attributable to payroll-related costs and higher materials, contract services and pipeline safety fees. The business incurred higher depreciation and amortization expense due to growth projects placed in service as discussed earlier, which was partially offset by fully depreciated assets. The business also incurred higher interest expense largely as a result of higher debt balances and higher property taxes.

•Other was impacted by the absence of the Company's 2023 gain of $186.6 million related to the tax-free exchange of its retained shares in Knife River. Partially offsetting the decrease in net income was lower operation and maintenance expense, largely a result of corporate overhead costs classified as continuing operations allocated to the construction materials business in 2023, which are not included in Other in 2024, and lower strategic initiative costs. Other also benefited from lower interest expense due to lower borrowings associated with funding strategic initiatives.

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2023 compared to 2022 The Company's consolidated earnings increased $47.2 million. The Company experienced increased earnings at each of its continuing businesses.

•The electric business experienced higher retail sales due to rate relief in North Dakota and Montana, an electric service agreement to provide power to a data center near Ellendale, North Dakota, and higher transmission interconnect upgrades. Electric earnings were partially offset by lower residential volumes, primarily due to cooler weather in the third quarter of the year.

•Natural gas distribution experienced higher retail sales revenue due to rate relief in Idaho and Washington, higher basic service charges, and recovery of short-term debt interest expense in Idaho related to increased gas costs. These increases were largely offset by higher operation and maintenance expense, primarily higher payroll-related costs. The natural gas distribution business also experienced a 6.6 percent decrease in retail sales volumes to all customer classes, largely due to warmer weather, which was partially offset by weather normalization and decoupling mechanisms.

•The pipeline's earnings increase was driven by higher transportation volumes, primarily from increased contracted volume commitments from the North Bakken Expansion project and a full year of benefit from this project; as well as organic growth projects placed in service in November 2023 and August 2022. In addition, revenues increased from new transportation and storage rates effective August 1, 2023 and higher storage-related activity. The pipeline also benefited from higher allowance for funds used during construction on organic growth projects, lower property taxes and higher non-regulated project margin. The increase was offset in part by higher operation and maintenance expense primarily attributable to payroll-related costs and contract services. The pipeline business also incurred higher interest expense as a result of higher interest rates and higher debt balances.

•Other experienced a realized gain of $186.6 million related to the tax-free exchange of its retained interest in Knife River and higher interest income. Partially offsetting these items were higher interest expense, primarily related to debt issued in connection with the Knife River separation. Other also benefited from improved claims experience at the captive insurer in 2023 compared to 2022.

•The Company's earnings from continuing operations were further impacted by $18.6 million in higher returns on the Company's nonqualified benefit plan investments, as discussed in Note 9, partially offset by higher costs incurred in connection with other strategic initiatives of $6.1 million, after tax.

A discussion of key financial data from the Company's business segments follows.

Business Segment Financial and Operating Data

Following are key financial and operating data for each of the Company's business segments. Also included are highlights on key growth strategies, projections and certain assumptions for the Company and its subsidiaries and other matters of the Company's business segments. Many of these highlighted points are "forward-looking statements." For more information, see Part I - Forward-Looking Statements. There is no assurance that the Company's projections, including estimates for growth and changes in earnings, will in fact be achieved. Please refer to assumptions contained in this section, as well as the various important factors listed in Item 1A - Risk Factors. Changes in such assumptions and factors could cause actual future results to differ materially from the Company's projections.

The Company’s CODM, the chief executive officer of MDU Resources Group, Inc., regularly reviews discrete financial information of each reportable segment and uses net income to assess performance of each reportable segment. The CODM uses this information to assess performance and make decisions about resources to be allocated to each reportable segment, including capital and personnel. The information provided to the CODM is prepared at the reportable segment level in quarterly financial packages and on a more summarized basis monthly. Budget and forecast information is also provided to the CODM at the reportable segment level.

For information pertinent to various commitments and contingencies, see Item 8 - Notes to Consolidated Financial Statements. For a summary of the Company's business segments, see Item 8 - Note 17.

Electric and Natural Gas Distribution

Strategy and challenges The electric and natural gas distribution segments provide electric and natural gas distribution services to customers, as discussed in Items 1 and 2 - Business Properties. Both segments strive to be top performing utility companies with a commitment to customers and communities, operational excellence, returns focused initiatives and an employee driven culture. The segments provide safe, reliable, competitively priced and environmentally responsible energy service to customers while focusing on growth and expansion opportunities within and beyond its existing territories. The Company is focused on cultivating organic growth while managing operating costs and monitoring opportunities for these segments to retain, grow and expand their customer base through extensions of existing operations, including building and upgrading electric generation, transmission and distribution, and natural gas systems, and through selected acquisitions of companies and properties with similar operating and growth objectives at prices that will provide stable cash flows and an opportunity to earn a competitive return on investment. The continued efforts to create operational improvements and efficiencies across both segments promotes the Company's business integration strategy. The primary factors that impact the results of these segments are the ability to earn authorized rates of return; weather; climate change laws, regulations and initiatives; competitive factors in the energy industry; population growth; and economic conditions in the segments' service areas.

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The electric and natural gas distribution segments are subject to extensive regulation in the jurisdictions where they conduct operations with respect to costs, timely recovery of investments and permitted returns on investment. The Company is focused on modernizing utility infrastructure to meet the varied energy needs of both its customers and communities while ensuring the delivery of safe, reliable, affordable and environmentally responsible energy. The segments continue to invest in facility upgrades to be in compliance with existing and known future regulations. To assist in the reduction of regulatory lag in obtaining revenue increases to align with increased investments, tracking mechanisms have been implemented in certain jurisdictions. The Company also seeks rate adjustments for operating costs and capital investments, as well as reasonable returns on investments not covered by tracking mechanisms. For more information on the Company's tracking mechanisms and recent rate cases, see Items 1 and 2 - Business Properties and Item 8 - Note 20.

These segments are also subject to extensive regulation related to certain operational and environmental compliance, cybersecurity, permit terms and system integrity. Both segments are faced with the ongoing need to actively evaluate cybersecurity processes and procedures related to its transmission and distribution systems for opportunities to further strengthen its cybersecurity protections. There have been cyber and physical attacks within the energy industry on infrastructure, such as substations, and the Company continues to evaluate the safeguards implemented to protect its electric and natural gas utility systems. Implementation of enhancements and additional requirements to protect the Company's infrastructure is ongoing.

To date, many states have enacted, and others are considering, mandatory clean energy standards requiring utilities to meet certain thresholds of renewable and/or carbon-free energy supply. Over the long-term, the Company expects overall electric demand to be positively impacted by increased electrification trends, including electric vehicle adoption, as a means to address economy-wide carbon emission concerns, data center growth and changing customer conservation patterns. Recently, MISO and NERC announced concerns with reliability of the electric grid due to rapid expansion of renewables and retirement of baseload resources such as coal and the uncertainty of adequate energy production during certain periods of time, while load growth has increased faster than expected. Montana-Dakota filed its 2024 IRP with the NDPSC on July 12, 2024. With MISO's filed changes in resources adequacy at FERC and the adoption of direct loss of load accreditation for generation resources around riskiest hours on the system versus peak load hours, Montana-Dakota is seeing the need to add additional capacity resources to its system in 2028 versus 2034 as identified in its previous IRP. The Company will continue to monitor the progress of these changes and assess the potential impacts they may have on its stakeholders, business processes, results of operations, cash flows and disclosures.

Revenues are impacted by both customer growth and usage, the latter of which is primarily impacted by weather, as well as impacts associated with commercial and industrial slow-downs, including economic recessions, and energy efficiencies. Very cold winters increase demand for natural gas and to a lesser extent, electricity, while warmer than normal summers increase demand for electricity, especially among residential and commercial customers. Average consumption among both electric and natural gas customers has tended to decline as more efficient appliances and furnaces are installed, and as the Company has implemented conservation programs. Natural gas weather normalization and decoupling mechanisms in certain jurisdictions have been implemented to largely mitigate the effect that would otherwise be caused by variations in volumes sold to these customers due to weather and changing consumption patterns on the Company's distribution margins, as further discussed in Items 1 and 2 - Business Properties.

In December 2022 and January 2023, natural gas prices significantly increased across the Pacific Northwest from multiple price-pressuring events including wide-spread below-normal temperatures and higher natural gas consumption; reduced natural gas flows due to pipeline constraints, including maintenance in West Texas; and historically low regional natural gas storage levels. Natural gas prices stabilized by March 2023. The higher natural gas prices in December 2022 and January 2023 impacted both Intermountain and Cascade, both of which borrowed short-term debt of $125.0 million and $150.0 million, respectively, in January 2023 to finance the increased natural gas costs. To assist in the recovery of higher natural gas costs, Intermountain filed an out-of-cycle purchased gas adjustment with the IPUC that was effective February 1, 2023, and collected interest costs associated with short-term borrowing. Effective November 1, 2023, as approved by the WUTC, Cascade started recovery in Washington of these increased gas costs over a period of two years rather than the normal one year period. In January 2024, Cascade and Intermountain made the final repayment on short-term debt of $50.0 million and $45.0 million, respectively. For a discussion of the Company's most recent cases by jurisdiction, see Item 8 - Note 20.

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In late summer and fall of 2023, electric fuel and purchased power prices increased across Montana-Dakota's integrated system. This was caused by transmission congestion in northwest North Dakota due to delays in additional SPP transmission line build-out, as well as additional load growth in the Bakken region. Electric fuel and purchased power prices remained elevated through January 2024. To assist in the recovery of the higher electric fuel and purchased power costs, Montana-Dakota filed waiver requests with the NDPSC and SDPUC, which were approved deferring the increased costs to the annual fuel clause adjustment. In Montana, the waiver request is filed monthly and was unopposed by the MTPSC. Montana-Dakota filed a complaint with FERC related to this issue on January 23, 2024. MISO also filed its own complaint with FERC against SPP on March 8, 2024. On September 10, 2024, FERC issued an order denying both Montana-Dakota and MISO's complaint regarding the issue. On October 10, 2024, Montana-Dakota and MISO filed with FERC for rehearing on FERC's decision to deny these complaints. Both rehearing requests were denied by operation of law on November 11, 2024. On January 2, 2025, Montana-Dakota filed a petition for review of the FERC decision with the United States Court of Appeals for the Eighth Circuit. MISO filed a petition for review of the FERC decision on January 8, 2025. On December 26, 2024, Montana-Dakota filed a request with the NDPSC for authorization to defer external legal expenses related to this congestion litigation and record those deferred expenses into a regulatory asset. Effective April 1, 2024, as approved by the NDPSC, Montana-Dakota started recovery in North Dakota of these increased costs over a period of two years rather than one year, which will lessen the impact to customers and allow more time for Montana-Dakota's FERC complaint to mature and have greater certainty of the outcome. In South Dakota and Montana, Montana-Dakota started recovery of these costs over a one-year period effective July 1, 2024.

The Company continues to proactively monitor and work with its manufacturers to reduce the effects of increased pricing and lead times on delivery of certain raw materials and equipment used in electric generation, transmission and distribution system and natural gas pipeline projects. Long lead times are attributable to increased demand for steel products from pipeline companies as they continue pipeline system safety and integrity replacement projects driven by PHMSA regulations, as well as delays in the manufacturing and shipping of electrical equipment and increased demand for electrical equipment due to regulatory activity and grid expansion. The Company has been able to minimize the effects by working closely with suppliers or obtaining additional suppliers, as well as modifying project plans to accommodate extended lead times and increased costs. The Company expects these delays and inflationary pressures to continue.

The ability to grow through acquisitions is subject to significant competition and acquisition premiums. In addition, the ability of the segments to grow their service territory and customer base is affected by regulatory constraints, the economic environment of the markets served, population changes and competition from other energy providers and fuel. The construction of new electric generating facilities, transmission lines and other service facilities is subject to increasing costs and lead times, extensive permitting procedures, and federal and state legislative and regulatory initiatives, which may necessitate increases in electric energy prices. As the industry continues to expand the use of renewable energy sources, the need for additional transmission infrastructure is growing. As part of MISO's long range transmission plan, in August 2022, the Company announced its intent to develop, construct and co-own JETx with Otter Tail Power Company in central North Dakota. On October 6, 2023, the FERC issued an order approving the Company's request for CWIP Incentive Rate and Abandoned Plant Incentive treatment on this project.

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Earnings overview - The following information summarizes the performance of the electric segment.

(In millions)

Operating expenses:

Operating statistics

Revenues (millions)

Retail sales:

Volumes (million kWh)

Retail sales:

Average cost of electric fuel and purchased power per kWh $ .025 $ .024 $ .026

Cooling degree days (% warmer (colder) than prior year)1

North Dakota (2.2) % (5.4) % (26.8) %

1Cooling degree days are a measure of the energy demand for cooling.

2024 compared to 2023 Electric earnings increased $3.2 million as a result of:

•Revenue increased $13.3 million.

◦Largely attributable to:

▪Rate relief of $7.1 million in North Dakota, South Dakota and Montana.

▪Higher fuel and purchased power costs of $6.4 million recovered in customer rates and offset in expense, as described below.