Item 1. BUSINESS

General

Martin Marietta Materials, Inc. (the Company or Martin Marietta) is a natural resource-based building materials company. The Company supplies aggregates (crushed stone, sand and gravel) through its network of approximately 360 quarries, mines and distribution yards in 28 states, Canada and The Bahamas. In 2023, aggregates gross profit accounted for 68% of the Company’s consolidated total gross profit. Martin Marietta also provides cement and downstream products, namely, ready mixed concrete, asphalt and paving services, in targeted markets where the Company has a leading aggregates position. The Company’s heavy-side building materials are used in infrastructure, nonresidential and residential construction projects. Aggregates are also used in agricultural, utility and environmental applications and as railroad ballast. The aggregates, cement, ready mixed concrete and asphalt and paving operations are reported collectively as the “Building Materials business”. The Company also operates a Magnesia Specialties business with production facilities in Michigan and Ohio. The Magnesia Specialties business produces magnesia-based chemical products that are used in industrial, agricultural and environmental applications. It also produces dolomitic lime sold primarily to customers for steel production and soil stabilization. Magnesia Specialties’ products are shipped to customers domestically and worldwide.

On May 3, 2023, the Company divested its Stockton cement import terminal in California. On October 31, 2023, the Company divested the Tehachapi, California cement plant for $315.0 million in cash. In connection with the Tehachapi cement plant transaction, the Company recorded a $26.3 million pretax loss on divestiture in discontinued operations. Since October 1, 2021 and through their respective divestiture dates, the aforementioned California operations were classified as assets held for sale and reported as discontinued operations. As of December 31, 2023, the Company has largely concluded the planned asset sales from the 2021 Lehigh Hanson, Inc. West Region business (Lehigh West Region) acquisition.

On January 16, 2024, the Company completed the acquisition of Albert Frei & Sons, Inc., a leading aggregates producer in Colorado, securing more than 60 years (at 2023 production levels) of high-quality, hard rock reserves. This transaction enhances the Company's aggregates platform in the high-growth Denver metropolitan area.

On February 9, 2024, the Company closed the sale of its South Texas cement business and certain of its related ready mixed concrete operations to CRH Americas Materials, Inc., a subsidiary of CRH plc, for $2.1 billion in cash. Specifically, the divested facilities included the Hunter cement plant in New Braunfels, Texas, related cement distribution terminals and 20 ready mixed concrete plants serving the Austin and San Antonio region. This divestiture optimizes the Company's portfolio and product mix and provides additional balance sheet flexibility to redeploy net proceeds into pure-play aggregates acquisitions. These operations are reported in the West Group and classified as assets held for sale as of December 31, 2023.

On February 11, 2024, the Company entered into a definitive agreement to acquire 20 active aggregates operations in Alabama, South Carolina, South Florida, Tennessee, and Virginia from affiliates of Blue Water Industries LLC (BWI Southeast) for $2.05 billion in cash. The BWI Southeast acquisition complements Martin Marietta’s existing geographic footprint in the dynamic southeast region by allowing the Company to expand into new growth platforms in target markets including Nashville and Miami. The transaction is expected to close during 2024, subject to regulatory approvals and other customary closing conditions.

Business Segment Information

The Company conducts its Building Materials business through two reportable segments, organized by geography: East Group and West Group. The East Group provides aggregates and asphalt products. The West Group provides aggregates, cement, downstream products and paving services. The Company’s Magnesia Specialties business is reported as a separate segment and includes its magnesia-based chemicals and dolomitic lime businesses. For more information on the organization and geographic area of the Company’s business segments, see “Note A: Accounting Policies” and “Note O: Segments” of the “Notes to Financial Statements” of the Company’s consolidated financial statements, which appear in Item 8, “Financial Statements and Supplementary Data,” of this Annual Report on Form 10-K (this Form 10-K), which information is incorporated by reference.

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Building Materials Business

The profitability of the Building Materials business, which serves customers in the construction marketplace, is sensitive to national, regional and local economic conditions and construction cyclicality, which are in turn affected by fluctuations in levels of public-sector infrastructure funding; interest rates; access to capital markets; and demographic, geographic, employment and population dynamics. The heavy-side construction business is conducted outdoors, as are much of the Building Materials business’ operations. Therefore, erratic weather patterns, seasonal changes, and other weather-related conditions, including precipitation, flooding, hurricanes, snowstorms, extreme temperatures, wildfires, earthquakes and droughts, can significantly affect production schedules, shipments, costs, efficiencies and profitability. Generally, the financial results for the first and fourth quarters are subject to the impacts of winter weather, while the second and third quarters are subject to the impacts of heavy precipitation.

The Building Materials business markets its products primarily to the construction industry, with 36% of its 2023 aggregates shipments sold to contractors in connection with highway and other public infrastructure projects and the balance of its shipments sold primarily to contractors for nonresidential and residential construction projects. The Company believes the business’ mix of public sector-related shipments lessens the impacts of fluctuations in nonresidential and residential, or private-sector, construction spending.

Funding of public infrastructure, historically the Company’s largest end-use market, is discussed in greater detail under “Building Materials Business’ Key Considerations—Public Infrastructure” in Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations,’’ of this Form 10-K.

The Building Materials business covers a wide geographic area. The ten largest revenue-generating states (Texas, North Carolina, Colorado, California, Georgia, Minnesota, Arizona, Iowa, Florida and Indiana) accounted for 82% of the Building Materials business’ total revenues in 2023. The Building Materials business is accordingly affected by the economies in these regions and has been adversely affected in part by recessions and weaknesses in these economies from time to time and may be affected by a decline in economic conditions, such as recession, economic downturn or inflationary conditions in the future. In 2023, aggregates shipments decreased 4.3%, largely reflective of the Company's value-over-volume strategy and moderating demand resulting from the affordability-driven residential slowdown and a softening in warehouse and data center construction demand.

Aggregates

Aggregates, consisting of crushed stone, sand and gravel, are an engineered, granular material that is manufactured to specific sizes, grades and chemistry for use primarily in construction applications. The Company’s operations consist primarily of open pit quarries; however, the Company is the largest operator of underground aggregates mines in the United States, with 14 active underground mines located in the East Group.

Natural aggregates sources can be found in relatively homogeneous deposits in certain areas of the United States. Proximity of quarry facilities to customers’ construction sites or to long-haul transportation corridors is an important factor in competition for aggregates businesses. As a general rule, the distance truck shipments travel from an individual quarry is limited because the cost of transporting processed aggregates to customers is high in relation to the price of the product itself. The Company’s distribution system mainly uses trucks, but also has access to rail and waterborne networks where the per-mile unit costs of transporting aggregates are lower.

The Company’s distribution network moves aggregates materials from certain domestic and offshore sources via its long-haul rail and waterborne distribution network, to markets where aggregates supply is limited. The Company’s rail network primarily serves its Texas, Florida, Colorado and Gulf Coast markets, while the Company’s locations in The Bahamas and Nova Scotia transport materials via oceangoing ships. The Company’s strategic focus includes expanding inland and offshore capacity and acquiring distribution facilities and port locations to offload transported material. At December 31, 2023, the Company’s aggregates distribution facilities consisted of 76 yards. The Company’s rail-based distribution network, coupled with the extensive use of rail service, increases the Company’s dependence on and exposure to railroad performance, including track congestion, crew availability, railcar availability, locomotive availability and the ability to negotiate favorable railroad shipping contracts. The waterborne distribution network also increases the Company’s exposure to certain risks, including, among other items, meeting minimum tonnage requirements of shipping contracts, demurrage costs, fuel costs, ship availability and weather disruptions. The Company has long-term agreements with shipping companies to provide ships to transport its aggregates to various coastal ports.

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The Company generally acquires contiguous property around existing quarry locations. Such parcels can serve as buffer property or additional mineral reserves, assuming the underlying geology supports economical aggregates mining. In either instance, the acquisition of additional property around an existing quarry typically allows the expansion of the quarry footprint and extension of quarry life. Some locations having limited reserves may be unable to expand.

Due to the nature of the indigenous aggregates supply in the midwestern United States, a long-term capital focus for the Company is underground limestone aggregates mines. Production costs are generally higher at underground mines than surface quarries since the depth of the aggregates deposits and the access to the reserves result in higher costs related to development, explosives and depreciation costs. However, these locations often possess marketplace transportation advantages that can lead to higher average selling prices than more distant surface quarries.

The construction aggregates industry has been consolidating, and the Company has actively participated in the industry’s consolidation. The Company’s Board of Directors and management continue to review and monitor the Company’s long-term strategic plans, commonly referred to as SOAR (Strategic Operating Analysis and Review), which include assessing portfolio optimization strategies that include business combinations and arrangements with other companies engaged in similar businesses, investing in internal expansion projects in high-growth markets, divesting businesses or nonoperating assets that are not core or do not further management’s strategy and pursuing new opportunities in the Company’s existing markets or new markets. Acquisition opportunities include public companies, public company carve-outs and private sponsor-owned and family-owned businesses, as well as asset swaps and divestitures from companies executing their strategic plans, rationalizing non-core assets and repairing financially-constrained balance sheets. When acquired, new locations sometimes do not satisfy the Company’s internal safety, maintenance, pit development or other standards, and may require additional investments before benefits of the acquisitions are fully realized.

Management believes its aggregates reserves are sufficient to permit production at present operational levels for the foreseeable future. The Company does not anticipate any significant difficulty in accessing reserves used for production. The Company’s aggregates reserves average approximately 75 years, based on the 2023 annual production level. However, certain locations may be subject to limited reserves and may not be able to expand. Moreover, environmental, zoning and land use regulations will likely make it harder for the Company to expand its existing quarries or develop new quarry operations. Although it cannot be predicted what policies will be adopted in the future by federal, state and local governmental bodies regarding these matters, the Company anticipates that future restrictions will likely make zoning and permitting more difficult, thereby potentially enhancing the value of the Company’s existing mineral reserves.

The Company generally sells its aggregates upon receipt of customer orders or requests. The Company generally maintains inventories of aggregates products in sufficient quantities to meet the requirements of customers.

Cement and Downstream Operations

Cement is the basic agent used to bind aggregates, sand and water in the production of ready mixed concrete. Similar to aggregates, cement is used in infrastructure projects, nonresidential and residential construction, and the railroad, agricultural, utility and environmental industries. Consequently, the cement industry is cyclical and dependent on the strength of the construction sector. At December 31, 2023, the Company had production facilities in Midlothian, Texas, south of Dallas/Fort Worth, and New Braunfels, Texas, north of San Antonio. These plants, which produce Portland and specialty cements, operated at 71% utilization in 2023. Clinker is the initial product in cement production, and the two Texas production facilities had a combined annual clinker capacity of 4.5 million tons in 2023. The Midlothian plant permit allows the Company to expand production by up to 0.8 million additional tons. The Company is currently undertaking a finishing capacity expansion project at the Midlothian plant, which is expected to be completed in mid-2024 and will provide 0.5 million tons of annual incremental cement capacity. Further, the Company has converted its plants to manufacture a less carbon-intensive Portland limestone cement, known as Type 1L, which has been approved by the Texas Department of Transportation. On February 9, 2024, the Company closed the sale of it South Texas cement business and related cement distribution terminals. This divestiture optimizes the Company's portfolio and product mix and provides additional balance sheet flexibility to redeploy net proceeds into pure-play aggregates acquisitions.

Calcium carbonate in the form of limestone is the principal raw material used in the production of cement. The Company in 2023 owned more than 600 million tons of limestone reserves adjacent to its Texas cement production plants on Company-owned property. The cement grade limestone reserves at the Hunter production facility in New Braunfels, Texas, were included with the February 2024 divestiture to CRH Americas Materials, Inc. Management believes that its reserves of limestone are sufficient to permit production at its cement plants at the current operational levels for the foreseeable future.

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Cement consumption is dependent on the time of year and prevalent weather conditions. According to the Portland Cement Association, nearly two-thirds of U.S. cement consumption occurs in the six months between May and October. Approximately 70% to 75% of all cement shipments are sent to ready mixed concrete operators. The remainder is shipped to manufacturers of concrete-related products, contractors, materials dealers and oil well/mining/drilling companies. The Company's cement operations generally deliver their products upon receipt of customer orders or requests. Inventory for products is generally maintained in sufficient quantities to meet rapid delivery requirements of customers**.**

Energy accounted for 18% of the cement total cost of revenues, excluding inventory change, in 2023. Therefore, cement profitability is affected by changes in energy prices and the available supply of these products. The Company currently has fixed-price supply contracts for portions of its natural gas, electricity and coal needs, but also consumes alternative fuel and petroleum coke. Further, profitability of the cement operations is also impacted by kiln maintenance, which typically is planned but requires a plant to be shut down for a period of time.

Ready mixed concrete is measured in cubic yards and specifically batched or produced for customers’ construction projects and then typically transported by mixer trucks and poured at the project site. The aggregates used for ready mixed concrete is a washed material with limited amounts of fines (such as dirt and clay). As of December 31, 2023, the Company operated 82 ready mixed concrete plants in Arizona and Texas, of which 20 plants located in the Austin and San Antonio region are classified as assets held for sale. These 20 plants were subsequently divested on February 9, 2024. Asphalt is most commonly used in surfacing roads and parking lots and consists of liquid asphalt, or bitumen, the binding medium, and aggregates. Similar to ready mixed concrete, each asphalt batch is produced to customer specifications. As of December 31, 2023, the Company operated 38 asphalt plants in Arizona, California, Colorado and Minnesota. The Company also offers paving services in California and Colorado. Market dynamics for these downstream product lines include a highly competitive environment and lower barriers to entry compared with aggregates and cement.

The cement and downstream operations results are affected by volatile factors, including energy-related costs, operating efficiencies and weather, to a greater extent than the Company’s aggregates operations. Liquid asphalt and cement serve as key raw materials in the production of hot mix asphalt and ready mixed concrete, respectively. Therefore, fluctuations in prices for these raw materials directly affect the Company’s operating results.

Magnesia Specialties Business

The Magnesia Specialties business produces and sells dolomitic lime from its Woodville, Ohio facility and manufactures magnesia-based chemical products for industrial, agricultural and environmental applications at its Manistee, Michigan facility. These magnesia-based chemical products have varying uses, including flame retardants, wastewater treatment, pulp and paper production and other environmental applications. In 2023, 66% of Magnesia Specialties’ total revenues were attributable to chemical products, 33% to lime, and 1% to stone sold as construction materials.

Magnesia Specialties generally delivers its products upon receipt of customer orders or requests. Inventory for products is generally maintained in sufficient quantities to meet rapid delivery requirements of customers. A significant portion of the 275,000-ton dolomitic lime capacity from a lime kiln at Woodville, Ohio is committed under a long-term supply contract. In 2023, 78% of the lime shipments in the Magnesia Specialties business was sold to third-party customers, while the remaining 22% was used internally as a raw material in making the business’ chemical products. Dolomitic lime products sold to external customers are used primarily by the steel industry. In 2023, 38% of the Magnesia Specialties’ total revenues were attributable to products used in the steel industry, primarily dolomitic lime. Accordingly, a portion of the revenues and profitability of the Magnesia Specialties business is affected by production and inventory trends in the steel industry. These trends are guided by the rate of consumer consumption, the flow of offshore imports and other economic factors. The dolomitic lime business runs most profitably at 70% or greater domestic steel capacity utilization. According to the Federal Reserve, domestic steel capacity utilization averaged 74% of capacity in 2023 versus 75% of capacity in 2022.

In the Magnesia Specialties business, a significant portion of costs is of a fixed or semi-fixed nature. The production process requires the use of natural gas, coal and petroleum coke. Therefore, fluctuations in their pricing directly affect operating results. To help mitigate this risk, the Magnesia Specialties business has fixed-price agreements for approximately 81% of its 2024 coal, petroleum coke and natural gas needs. For 2023, the Company’s average cost per MMBtu (1,000,000 British thermal units) of natural gas decreased 19% versus 2022.

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Given high fixed costs, low capacity utilization can negatively affect the segment’s results from operations. Management has shifted the strategic focus of the magnesia-based business to grow and diversify the specialty chemicals product portfolio to reliably produce at volume levels that support efficient operations. Accordingly, these products are less dependent on the steel industry than the dolomitic lime product line. Management expects future organic profit growth to result from increased pricing, commercialization of new products, entry into new or adjacent markets and optimization of overall product mix.

The principal raw materials used in the Magnesia Specialties business are dolomitic limestone and magnesium-rich brine. Management believes that its reserves of dolomitic limestone and brine are sufficient to permit production at the current operational levels for the foreseeable future.

The Magnesia Specialties business is highly dependent on rail transportation, particularly for movement of dolomitic lime from Woodville to Manistee and direct customer shipments of dolomitic lime and magnesia chemicals products from both Woodville and Manistee. The segment can be affected by the specific transportation and other risks and uncertainties outlined under Item 1A, “Risk Factors,” of this Form 10-K.

Patents and Trademarks

As of January 31, 2024, the Company owns, has the right to use, or has pending applications for patents pending or granted by the United States and various countries and trademarks related to its business. The Company believes that its rights under its existing patents, patent applications and trademarks are of value to its operations, but no one patent or trademark or group of patents or trademarks is material to the conduct of the Company’s business as a whole.

Customers

The Company’s products are sold principally to commercial customers in private industry. Although large amounts of construction materials are used in public works projects, relatively insignificant sales are made directly to federal, state, county or municipal governments, or agencies thereof. No material part of the business as a whole, or of any segment of the Company, is dependent upon a single customer or upon a few customers. The loss of any single customer would not have a material adverse effect on the Company.

Competition

The nature of the Company’s competition varies among its products due to the widely differing amounts of capital necessary to build and maintain production facilities. Crushed stone production from quarries or mines and sand and gravel production by dredging or otherwise are moderately capital intensive. Construction of cement production facilities is highly capital intensive and requires long lead times to complete engineering design, obtain regulatory permits, acquire equipment and construct a plant. Most domestic cement producers are owned by large foreign companies operating in multiple international markets. Many of these producers maintain the capability to import cement from foreign production facilities. Ready mixed concrete production requires relatively small amounts of capital to build a concrete batching plant and acquire delivery trucks. Accordingly, economics can lead to lower barriers to entry in some concrete markets. As a result, depending on the local market, the Company may face competition from small producers as well as large, vertically-integrated companies with facilities in many markets.

The Company operates in a largely fragmented industry, including large, public companies and a large number of small, privately-held companies. Other publicly traded companies among the ten-largest U.S. aggregates producers include the following:

Arcosa, Inc.

CEMEX S.A.B. de C.V.

CRH plc

Heidelberg Materials AG

Holcim Ltd.

Knife River Corporation

Summit Materials, Inc.

Vulcan Materials Company

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Due to the localized nature of the industry resulting from the high cost of transportation relative to the price of the product, the Building Materials business primarily operates in smaller distinct areas that can vary from one another. The Company believes that its ability to transport materials by rail and waterborne vessels has enhanced its ability to compete in the building materials industry.

Capacity for cement plants is often stated in terms of clinker capacity. According to the Portland Cement Association, United States cement production is widely dispersed, with the top five companies collectively producing approximately 57% of U.S. clinker capacity. An estimated 85% of U.S. clinker capacity is owned by companies headquartered outside of the United States. The Company’s cement operations also compete with imported cement because of the higher value of the product and the existence of major ports or terminals in Texas.

The Company’s ready mixed concrete and asphalt and paving operations are also in markets with numerous operators, large and small.

The Magnesia Specialties business competes with various companies in different geographic and product areas principally on the basis of quality, price, technological advances and technical support for its products. While the revenues of the Magnesia Specialties business in 2023 were predominantly domestic, a portion was derived from customers located outside the United States.

Environmental and Governmental Regulations

Overview

The Company’s operations are subject to and affected by federal, state and local laws, rules and regulations relating to zoning, land use, mining, air emissions (including carbon dioxide and other greenhouse gases), water use, allocation and discharges, waste management, noise and dust exposure control, reclamation and other environmental, health and safety, and regulatory matters. Certain of the Company’s operations may from time to time involve the use of substances that are classified as toxic or hazardous within the meaning of these laws and regulations. Environmental operating permits are, or may be, required for certain of the Company’s operations, and such permits are subject to modification, renewal and revocation.

Environmental Compliance and Costs

The Company regularly monitors and reviews its operations, procedures and policies for compliance with existing laws, rules and regulations, changes in interpretations of existing laws and enforcement policies, new laws that are adopted and new laws that the Company anticipates will be adopted that could affect its operations, including with respect to climate change. The Company has a full-time team of environmental engineers and managers that perform these responsibilities. The direct costs of ongoing environmental compliance were approximately $45.4 million in 2023 and $35.6 million in 2022 and are related to the Company’s environmental staff, ongoing monitoring costs for various matters (including those matters disclosed in this Form 10-K) and asset retirement costs. Capitalized costs related to environmental control facilities were $24.4 million in 2023 and are expected to be approximately $25.0 million in 2024 and $30.0 million in 2025. The Company’s capital expenditures for environmental matters were not material to its results of operations or financial condition in 2023 and 2022. However, the Company’s expenditures for environmental matters generally have increased over time and are likely to increase in the future. Despite the Company’s compliance efforts, the risk of environmental liability is inherent in the Company’s businesses, and environmental liabilities could have a material adverse effect on the Company in the future. Complying with governmental and environmental regulations did not have and is not expected to have a material effect on the Company’s capital expenditures, earnings and competitive position, other than as discussed in this section.

Many of the applicable requirements of environmental laws are satisfied by procedures that the Company adopts as best practices in the ordinary course of its business. For example, plant equipment that is used to crush aggregates products may, in the ordinary course of operations, have an attached water spray bar that is used to clean the stone. The water spray bar also serves as a dust control mechanism that complies with applicable environmental laws. Moreover, the Company does not separate the portion of the cost, depreciation and other financial information relating to the water spray bar that is attributable only to environmental purposes, as such an allocation would be arbitrary. The incremental portion of such operating costs that is attributable to environmental compliance rather than best operating practices is impractical to quantify. Accordingly, the Company records costs in that category when incurred as operating expenses.

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Consistent with others in the cement industry, the Company’s cement operations produce varying quantities of cement kiln dust (CKD). This production by-product consists of fine-grained, solid, highly alkaline material removed from cement kiln exhaust gas by air pollution control devices. Since much of the CKD is unreacted raw materials, it is generally permissible to recycle the CKD back into the production process, and large amounts often are treated in such manner. CKD that is not returned to the production process or sold as a separate product is disposed in landfills. CKD is currently exempted from federal hazardous waste regulations under Subtitle C of the Resource Conservation and Recovery Act.

The environmental accruals recorded by the Company are based on internal studies of the required remediation costs and estimates of potential costs that arise from time to time under federal, state and/or local environmental protection laws. Many of these laws and their attendant regulations are complex and are subject to challenges and new interpretations by regulators and the courts. In addition, new laws are also enacted from time to time. It is often difficult to accurately and fully quantify the costs to comply with new rules until it is determined to which type of operations they will apply and the manner in which they will be implemented is more accurately defined. This process typically takes years to finalize, and the rules often change significantly from the time they are proposed to the time they are final. The Company typically has several appropriate alternatives available to satisfy compliance requirements, which could range from nominal costs to some alternatives that may be satisfied in conjunction with equipment replacement or expansion that also benefit operating efficiencies or capacities and carry significantly higher costs.

Management believes that its current accrual for environmental costs is reasonable, although those amounts may increase or decrease depending on the impact of applicable rules as they are finalized or amended from time to time and changes in facts and circumstances. The Company believes that its operations and facilities, both owned or leased, are in substantial compliance with applicable laws and regulations and any potential noncompliance is not likely to have a material adverse effect on the Company’s operations or financial condition. See “Legal Proceedings" under Item 3 of this Form 10-K, “Note N: Commitments and Contingencies” of the “Notes to Financial Statements” of the Company’s consolidated financial statements included under Item 8, “Financial Statements and Supplemental Data,” of this Form 10-K, and the “Environmental Regulation and Litigation" section included under Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” of this Form 10-K. However, future events, such as changes in or modified interpretations of existing laws and regulations or enforcement policies, or further investigation or evaluation of the potential health hazards of certain products or business activities, may give rise to additional compliance and other costs that could have a material adverse effect on the Company.

Mine Safety and Land Reclamation

In general, mining, production and distribution facilities for aggregates, cement, ready mixed concrete and asphalt must comply with air quality, water quality and other environmental regulations, zoning and special use permitting requirements, applicable mining regulations, and federal health and safety requirements. As the Company locates and acquires new production and distribution facilities, the Company works closely with local authorities during the zoning and permitting processes to design new quarries, mines, production and distribution facilities in such a way as to minimize disturbances. The Company frequently acquires large tracts of land so that quarry, mine, production and distribution facilities can be situated at a substantial distance from surrounding property owners. Also, in certain markets, the Company’s ability to transport material by rail or water allows it to locate its facilities further away from residential areas. The Company has established policies designed to minimize disturbances to surrounding property owners from its operations.

As is the case with other similarly situated companies, some of the Company’s products contain varying amounts of crystalline silica, a common mineral also known as quartz. Excessive, prolonged inhalation of very small-sized particles of crystalline silica has been associated with lung diseases, including silicosis, and several scientific organizations and some states, such as California, have reported that crystalline silica can cause lung cancer. The Mine Safety and Health Administration (MSHA) and the Occupational Safety and Health Administration (OSHA) have established occupational thresholds for crystalline silica exposure as respirable dust. The Company monitors occupational exposures at its facilities and implements dust control procedures and/or makes available appropriate respiratory protective equipment to maintain the occupational exposures at or below the required levels. The Company, through safety information sheets and other means, also communicates appropriate warnings and cautions its employees and customers about the risks associated with excessive, prolonged inhalation of mineral dust in general and crystalline silica in particular.

The Company is generally required by state or local laws or pursuant to the terms of an applicable lease to reclaim quarry sites after use. Future reclamation costs are estimated using statutory reclamation requirements and management’s experience and knowledge in the industry, and are discounted to their present value using a credit-adjusted, risk-free interest rate. The future reclamation costs are not offset by potential recoveries. For additional information regarding compliance with legal

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requirements, see “Note N: Commitments and Contingencies” of the “Notes to Financial Statements” of the Company’s consolidated financial statements included in Item 8, “Financial Statements and Supplemental Data,” of this Form 10-K. The Company performs activities on an ongoing basis, as an integral part of the normal quarrying process, that may reduce the ultimate reclamation obligations. For example, the perimeter and interior walls of an open pit quarry are sloped and benched as they are developed to prevent erosion and provide stabilization. This sloping and benching meets both safety regulations required by MSHA for ongoing operations as well as final reclamation requirements. Therefore, these types of activities are included in normal operating costs and are not a part of the asset retirement obligation. Reclaimed quarry sites owned by the Company are from time to time available for sale, typically for commercial development or use as water reservoirs, or have been converted for recreational use by the local community.

Climate Change Risks and Opportunities

The Board and management have identified certain risks related to the transition to a lower-carbon economy, risks related to the physical impacts of climate change and other climate-related opportunities.

Board Oversight and the Role of Management The Board of Directors has an essential role in determining the Company's strategic priorities, and climate change and other sustainability matters are an integral part of its governance and oversight of the business. In 1994, the Company established an Ethics, Environment, Safety and Health (EESH) Committee, which currently meets at least four times annually. The EESH Committee receives reports directly from management relating to environmental, safety, ethics and other sustainability matters, including greenhouse gas (GHG) and climate change-related matters, reviews input and engagement with investors on these matters, and monitors the Company's compliance with environmental, health and safety laws and regulations, as well as its public reporting and disclosure with respect to climate change-related risks and opportunities and other environmental issues. The EESH Committee reports to the full Board, and a number of other Board committees have overlapping responsibility for sustainability matters, including the Audit Committee, which reviews the Company's significant environmental matters and assesses the potential risks and liabilities they may pose to its business, and the Management Development and Compensation Committee, which reviews management's performance with regard to its sustainability goals and considers those achievements in determining incentive pay. While the Board oversees Martin Marietta's risk management, the executive officers are responsible for the day-to-day risk management processes, and management receives at least quarterly updates from operating personnel directly responsible for compliance relating to EESH matters. Management believes this division of responsibilities is the most effective approach for addressing the risks facing the Company. The Company also has a Head of Sustainability, who reports directly to the Executive Vice President and General Counsel on climate and other sustainability matters. The Company believes the above approach has been effective in integrating sustainability as a core element of its corporate governance.

Transition Risks

The Company's sustainability risk management framework is designed to identify various transition risks, including policy and legal risks, technology risks, market risks and reputation risks, associated with climate change and transitions to a lower-carbon economy.

Policy and Legal Risks A number of governmental bodies, including the U.S. Congress and various U.S. states, have proposed, enacted or are contemplating legislative and regulatory changes to mitigate or address the potential impacts of climate change, including provisions for GHG emissions reporting or reductions, the use of alternative fuels, carbon credits (such as a cap-and-trade system) and a carbon tax. For example, in the United States, the United States Environmental Protection Agency (USEPA) promulgated a rule mandating that companies considered to be large emitters of GHGs report those emissions. The manufacturing operations of the Company’s Magnesia Specialties business release carbon dioxide, methane and nitrous oxides during the production of lime, magnesium oxide and hydroxide products. The Company’s two magnesia-based chemicals facilities, as well as its cement operations in Texas, file annual reports of their GHG emissions in accordance with the USEPA reporting rule. The primary business and operations of the Company, however, including its aggregates, ready mixed concrete and asphalt and paving product lines, are not considered “major” sources of GHG emissions subject to the USEPA reporting rule. Most of the GHG emissions from aggregates plant operations are tailpipe emissions from mobile sources, such as heavy construction and earth-moving equipment.

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The Company’s cement plants, as well as its Magnesia Specialties plants, are strictly regulated with respect to GHG emissions and hold Title V Permits, and each (other than the Manistee, Michigan facility) is also subject to the U.S. Clean Air Act's Prevention of Significant Deterioration (PSD) requirements which require a permit program for certain new or modified sources of emissions. Although several large-scale projects for carbon capture are in the development phase, no technologies or methods of operation for reducing or capturing GHGs have yet been proven successful in large-scale applications, other than improvements in fuel efficiency. If future modifications to the Company's facilities require PSD review for other pollutants, GHG permitting requirements may also be triggered and may require significant additional costs, which the Company expects would be passed on to customers. It is not currently possible to estimate the cost of any such future requirements. In addition, the USEPA and the U.S. Supreme Court have taken different positions with respect to the USEPA's authority to make rules in these and other areas which could create uncertainty regarding regulatory compliance on these matters in the future.

In 2021, a pair of executive orders and a presidential memorandum were issued making climate change central to U.S. policy and setting out several administrative priorities and undertakings to reduce GHG emissions. The United States reentered the Paris Agreement in January 2021 and later announced the U.S. reduction commitments under the Paris Agreement, including a 50% to 52% economy-wide reduction in net GHG emissions from 2005 levels by 2030. The United States also entered a pact with 103 countries and jurisdictions, known as the Global Methane Pledge, to reduce global methane emissions by 30% from 2020 levels by the end of the decade.

In November 2021, President Biden signed into law the Infrastructure Investment and Jobs Act (IIJ Act), which provides billions of dollars in new funding for public transit and clean energy projects intended, in part, to address climate change, including road, bridge and other major infrastructure projects. These projects, as well as new public transit and clean energy projects, require aggregates and cement for construction and may result in increased demand for the Company's products. See Climate-Related Opportunities section for additional information.

Although it is impossible to determine the actions the federal government will ultimately take to implement climate change-related orders, commitments and laws, or the full scope, timing or ramifications of such measures, the United States, like other signatories to the Paris Agreement, is currently pursuing a goal of a Net Zero GHG by 2050. It is also possible that the USEPA and other agencies will use their rule-making authority and procurement decisions to further address climate change. Various states where the Company has operations have enacted or are considering climate change initiatives as well, and the Company may have been and may continue to be subject to state regulations in addition to any federal laws and rules that are passed. In October 2023, California adopted its California Climate Accountability Package which includes annual reporting of Scope 1, Scope 2 and Scope 3 emissions on a phased-in implementation schedule, climate-related risk reporting for certain companies and heightened disclosure standards around net zero emissions claims, carbon-neutral claims or significant GHG emissions reduction claims and the purchase or use of voluntary carbon offsets used to achieve those claims. These rules have been challenged and may be challenged in the future by various groups and the future resolution of such challenges are unknown at this time. In addition, certain other states are enacting laws and regulations that seek to eliminate the consideration of climate-related matters in state pension fund investment decisions and other company programs. These and other state climate-related or anti-climate, social and governance regulations may result in significantly higher compliance costs and risks.

If and when the USEPA issues new regulations and/or Congress passes additional legislation restricting GHGs emissions, the Woodville, Ohio and Manistee, Michigan Magnesia Specialties operations, as well as the Company’s cement plants in Texas, which release CO2 in certain of their processes and use carbon-based fuels for power equipment, kilns and the Company’s mobile fleet, will likely be subject to these new regulations. The Company's cement operations, like those of other cement producers, require combustion of significant amounts of fuel to generate high kiln temperatures and create carbon dioxide as a product of the calcination process, which is presently an unavoidable step in making clinker, the essential component for the production of cement. Accordingly, the Company continues to closely monitor GHG regulations and legislation and its potential impact on the Company's cement business, financial condition and product demand. The Company anticipates that any increased operating costs or taxes relating to GHG emission limitations at the Woodville or cement facilities would be passed on to customers. The magnesium oxide products produced at the Manistee operation, however, compete against other products that, due to the form and/or structure of the source material, require less energy in the calcination process, resulting in the generation of fewer GHGs per ton of production. Due to GHG emissions requirements, the Manistee facility may be required to absorb additional costs, including for taxes or capital investments, in order to maintain competitive pricing in that market. In addition, the cement produced by the Company’s cement operations, like other U.S. producers, is subject to strict limits set by the U.S. Department of Transportation (USDOT) and other agencies, including those relating to “clinker substitution”, or the replacement of ground clinker in cement with alternate materials such as pozzolan, slag and fly ash, which has implications for the Company’s fuel use and efforts to reduce GHG emissions from its cement operations. For example,

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Part I ♦ Item 1 – Business

various industry associations are engaged in an effort requesting the USDOT and other agencies to further revise their standards allowing for greater rates of clinker substitution, similar to the rates currently permitted for European cement producers. If higher rates of substitution and blending are, in fact, permitted in the future, the result is likely to be both reduced clinker and power consumption in cement production, which would, in turn, reduce GHGs emitted in connection with each ton of cement produced in the United States. With the acceptance of Portland Limestone Cement (PLC) by the Texas Department of Transportation, in 2022, the Company embarked on a rollout of PLC cement, and by the end of 2022, the Company had converted 90% of its Type I/II customers in Texas to the PLC product. PLC cement may reduce the GHG footprint of the Company's cement product line up to 10%.

In light of the various regulatory uncertainties, the Company cannot presently reasonably predict the costs of any future compliance requirements. Nonetheless, the Company does not believe it will have a material adverse effect on the financial condition or results of the operations of either the Magnesia Specialties business or Building Materials business.

Technology Risks Consideration of the impact of technology is integrated into the Company’s risk management process. In an effort to mitigate the risks to the Company associated with climate change while ensuring and improving financial sustainability, the Company has adopted a corporate-wide management strategy, which has resulted in multiple initiatives to identify and implement or evaluate GHG reduction processes and technologies that also improve operational efficiencies, including: using alternative fuels such as biodiesel; reducing overall fuel use by converting from quarry trucks to conveyor systems; right-sizing quarry trucks to match the appropriately sized truck with the size of production to reduce the number of required trips; replacing older railcars with more efficient, high-capacity models that reduce the number of required trips; adding rail capacity in lieu of truck movements; and installing state-of-the-art emissions control equipment at one of the Company’s magnesia plants and tire processing systems for fuel, as well as a larger natural gas line, at one of the Company’s cement plants. The Company’s Midlothian cement plant has been recognized by the USEPA as a high-performing, energy-efficient facility following investments in innovative air pollution control technologies and usage of alternative fuels. The road to Net Zero for the Company and others in its industry requires operational changes, investments in sustainable energy, and in some cases, technology that is not yet available. The Company continues to monitor various pilot projects being conducted relating to the development of carbon capture technology; however, no technologies or methods of operation for reducing or capturing GHGs from cement manufacture have yet been proven successful in a full production environment, other than improvements in fuel efficiency. While awaiting further development of carbon capture technology, the Company has invested heavily and continues to look for opportunities to invest in its sustainability practices.

Market Risks The nature of the Company’s competition varies among its products due to the differing amounts of capital necessary to build and maintain production facilities and can be influenced by climate-related risks and opportunities particularly with respect to the Company’s small-but-strategic heritage cement business. Most domestic cement producers are owned by large non-U.S. companies operating in multiple international markets that report their results (including sustainability and climate-related metrics) on a world-wide consolidated basis. The Company is subject to U.S. environmental regulations and there are critical regulatory differences between the U.S. and the European Union and differing calculation methodologies for carbon intensity calculations, blending and fuel choice that result in meaningful differences in the makeup of corresponding end-products and reported emissions metrics. Those differences, in turn, make like-for-like comparisons of the emissions performance with the performance of the Company's heritage cement business challenging. To the extent that investors or consumers decide to use world-wide comparisons of these metrics in making investment and purchase decisions, the Company could be at a competitive disadvantage. Geography is critically important when assessing market attractiveness and growth opportunities for the Company. Attractive geographies generally exhibit (a) population growth and/or high population density, both of which are drivers of heavy-side building materials consumption; (b) business and employment diversity, drivers of greater economic stability, and (c) a superior state financial position, a driver of public infrastructure investment. All of these factors can be and are influenced by climate change and physical risk and opportunities.

Reputation Disruptions to the Company’s operations and to its customers' transportation activities by climate-related risks could impact the Company’s reputation and result in additional costs to the Company. Any failure or perceived failure to achieve or accurately report on the Company's current or future climate-related commitments, including its GHG reduction and net zero targets, and any differences between its commitments and those of any companies to which the Company is compared, could harm the Company's reputation, adversely affect its ability to effectively compete (including as a result of disclosure of proprietary information regarding its plants or changes in its ability to raise capital), adversely affect its recruitment and retention efforts or expose the Company to potential legal liability. In addition, while the Company is committed to pursuing its sustainability objectives, there is no assurance that it will achieve any of its sustainability goals or commitments, that low- or non-carbon-based energy sources and technologies required to meet long-term emissions reductions in some of the sectors

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Part I ♦ Item 1 – Business

in which it operates will be available at scale in the United States on an economically feasible basis or that its suppliers can meet sustainability, diversity and other standards that are required by current or future laws or established by its investors and other stakeholders. Failure to meet these commitments could result in reputational harm to the Company and changes regarding climate risk management and practices may result in higher regulatory and compliance risks and costs. Any violations of law (including environmental law) or improper conduct could damage the Company's reputation.

Physical Impacts In addition to impacts from increased regulation, climate change may result in physical impacts that could have adverse effects on the Company’s operations or financial condition. Physical impacts may include disruptions in production and/or regional supply or product distribution networks due to major storm events, shifts in regional rainfall and temperature patterns and intensities, as well as flooding from sea level changes. In addition, production and shipment levels for the Building Materials business correlate with general construction activity, which occurs outdoors and, as a result, is affected by erratic weather patterns, seasonal changes and other unusual or unexpected weather-related conditions, which can significantly affect that business. In the Company's cement and downstream operations businesses, the physical impacts of climate change may result in disruptions to its operations or its customers’ transportation activities, including impacts on production capabilities and capacities, supply chain interruptions and project delays that can impact the Company's reputation and result in additional costs to the Company. Excessive rainfall and other severe weather jeopardize production, shipments and profitability in all markets served by the Company in its Building Materials business. In addition, climate and inclement weather can reduce the useful life of an asset. In particular, the Company’s operations in the Atlantic and Gulf Coast regions of the United States and The Bahamas are at risk for hurricane activity, most notably in August, September and October. The Company is also at risk for Pacific Ocean storm activity. The last few years brought an unprecedented amount of precipitation to the United States and particularly to Texas and the southeastern United States, notably the Carolinas, Florida and Georgia, where it impacted the Company’s facilities. In California and Arizona, drought conditions have led to water use restrictions in numerous water districts, and insufficient supply of water for the Company's operations in those areas could impact production. In California, early 2023 storms and flooding caused operational delays and challenges. While reconstruction activities may offset some or most of the financial impacts on sales and demand, any of these events could have a material adverse effect on the Company’s business and operations.

As the Company's footprint of quarries and aggregates facilities has grown nationwide, management believes it has bolstered resilience in its operations by maintaining a geographically diverse business and distribution network that is increasingly able to adjust to local disruptions and source materials from different facilities. In addition, because the Company transports aggregates products by various methods, including rail and water, it may be able to mitigate supply or transportation issues in any location caused by severe weather or disruptions in any transport modality.

Climate-Related Opportunities Notwithstanding the foregoing risks and uncertainties relating to climate change, there may also be opportunities for the Company to increase its business or revenues, both in terms of the physical impacts of climate change and market opportunities associated with the transition to a low-carbon and climate-resilient economy. For example, warm and/or moderate temperatures in March and November allow the construction season to start earlier and end later, respectively, which could have meaningfully positive impacts on the Company’s first- and fourth-quarter results, respectively. From a regulatory standpoint, as noted above, the IIJ Act provides billions of dollars in new funding for roads, bridges and other major infrastructure projects which require aggregates and cement for construction. New public transit and clean energy projects that address climate change may also result in increased demand for the Company's products. Other opportunities are likely to result from the passing of the $1.2 trillion IIJ Act, the Cornyn-Padilla Amendment that allows $104 billion of unused COVID-19 dollars to be directed to infrastructure projects, and $7.0 billion of voter-approved state and local transportation-related 2023 ballot initiatives, all of which will fund infrastructure growth, repair and development. In addition, the Company’s magnesium hydroxide products are used to increase fuel efficiency in various industries, including both coal- and gas-fired electricity generation, which has a direct impact on reducing energy use and GHG emissions by more GHG-intense companies. Finally, the desire for sustainable building solutions has led to greater recognition of the benefits of concrete construction in the effort to move to a circular economy through innovative products, longevity and recyclability, and increased demand for green construction projects would have a direct impact on the Company’s cement and concrete business.

Land Management

The Company owns approximately 160,000 acres of land, the vast majority of which is used in connection with active facilities. The Company regularly reviews its land holdings to determine their highest and best use based on its management expertise. Land holdings that do not have economically recoverable reserves for current or future mining or are otherwise not in locations that complement the Company’s operating facilities are considered candidates for sale or development for sale.

Form 10-K ♦ Page 11

Part I ♦ Item 1 – Business

Human Capital Resources

As of January 31, 2024, the Company has approximately 9,400 employees, of which approximately 7,000 are hourly employees and approximately 2,400 are salaried employees. Approximately 1,200 hourly employees (12% of the Company’s employees) are represented by labor unions, representing 14% of the Building Materials business’ hourly employees and 100% of the Magnesia Specialties segment’s hourly employees. The Company’s principal union contracts for the Magnesia Specialties business cover employees at the Manistee, Michigan, magnesia-based chemicals plant and the Woodville, Ohio, lime plant. The Woodville and Manistee collective bargaining agreements expire in June 2026 and August 2027, respectively. The Company believes it has good relations with its employees, including its unionized workforce.

Management believes the Company’s success depends on its ability to attract, develop and retain key personnel. Martin Marietta offers a comprehensive benefits package that includes:

Competitive compensation;

401(k) with company match;

Company-funded pension plan;

Medical (PPO and HDHP/HSA plan options);

Dental and vision coverage;

Flexible spending accounts;

Paid holidays and generous paid time off;

Educational/tuition assistance plan (described in more detail below);

Employee discount program;

Adoption assistance program;

Life, AD&D and disability insurance;

Employee assistance program; and

Wellness programs.

The Company significantly enhanced company-provided benefits for its hourly employees in 2022 and 2023. The Company increased the benefit value for hourly employees in its currently fully funded pension plan by 76% in 2022. In conjunction with this increase, the Company embarked on a comprehensive education campaign to help employees better understand their retirement benefits and how that impacts their individual decisions to save for retirement. Additionally, in 2023, the Company added company-paid, long-term disability insurance for its hourly employees and implemented a more robust paid time off (PTO) policy, which increased PTO benefits for the vast majority of employees.

The Company’s management oversees various employee initiatives to develop its employees and the Management Development and Compensation Committee regularly reviews the compensation and development programs to achieve those objectives. The Company offers many training and development opportunities, including the following:

On-the-job training in the field and through the Company's Martin Marietta University, an interactive learning management system that serves as the gateway to a variety of valuable learning resources that support employee development;

A management associate program which provides entry-level opportunities for engineering, geology or STEM graduates in the aggregates industry. This is a 12-to-18-month on-the-job training that allows recent college graduates to jump-start their career by gaining cross-functional experience and developing transferable skills at an accelerated pace. The program includes job rotations, training and executive mentorship.

An Educational Assistance Program available for undergraduate and graduate degrees as well as individual vocational, undergraduate or graduate courses specifically related to an employee’s field;

A partnership with the University of North Carolina to provide a Leadership Program for senior managers and executives;

A partnership with North Carolina State University to provide a leadership program for managers;

An internal job board, as well as communications, reminding employees about this resource; and

A robust performance review process.

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Part I ♦ Item 1 – Business

In 2020, the Company launched an Inclusion and Engagement Task Force, comprised of employees with diverse race, gender, background and experience, focused on hiring, developing and retaining diverse employees to strengthen its talent pipeline and increase employee engagement and retention. The Company also developed and launched an inclusion and engagement awareness communications campaign to help managers and employees better understand the importance of inclusion and engagement matters and how inclusion and engagement are already ingrained in Martin Marietta’s culture and values. The campaign supports the Company's employer brand — ONE, which brings together its employees’ unique perspectives, experiences and talents to evolve a shared vision and future. In 2022, the Company began launching employee resource groups starting with a Military and Veterans Community resource group. In 2023, the Company introduced the Multicultural Employee Resource Group (MERGE) and the Women Who Build resource group. The Company has joined the CEO Action for Diversity & Inclusion coalition and has expanded its academic outreach by partnering with Shaw University, a historically Black university in Raleigh, North Carolina.

Health and safety in the workplace is one of the Company’s core values. The Guardian Angel safety program provides that every employee has the right, and the obligation, to stop any unsafe condition and that zero safety incidents is achievable. It includes the notion that every employee acts as a wingman for other employees, to observe and act on any situation that potentially creates unsafe circumstances. The companywide safety performance achieved the seventh consecutive year of world class or better lost-time incident rate and the third consecutive year for total injury incidence rate.

The Company also established a World Class Task Force, whose mission is to promote continuous improvement. The Company has taken these steps to better allow it to grow responsibly and encourage employee engagement.

Available Information

The Company maintains an internet address at www.martinmarietta.com. The Company makes available free of charge through its internet website its Annual Report on Form 10‑K, Quarterly Reports on Form 10‑Q, Current Reports on Form 8‑K, and amendments to those reports, if any, filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (Exchange Act), which are available as soon as reasonably possible after they are submitted to the Securities and Exchange Commission (SEC). You can access the Company’s filings with the SEC through the SEC website at www.sec.gov or through the Company's website, and the Company strongly encourages you to do so. Martin Marietta routinely posts information that may be important to investors on its website at www.ir.martinmarietta.com, and it uses this website address as a means of disclosing material information to the public in a broad, non-exclusionary manner for purposes of the SEC’s Regulation Fair Disclosure (Reg FD). The contents of the Company's website are not incorporated by reference in this Form 10-K and shall not be deemed “filed” under the Securities Exchange Act of 1934, as amended. The Company undertakes no obligation to update any statements herein for revisions or changes after the filing date of this Form 10-K other than as required by law.

The Company has adopted a Code of Ethical Business Conduct that applies to all of its Board of Directors, officers and employees. The Company’s code of ethics is available on the Company’s website www.martinmarietta.com. The Company will disclose on its internet website any waivers of or amendments to its code of ethics as it applies to its directors and executive officers.

The Company has adopted a set of Corporate Governance Guidelines to address matters of fundamental importance relating to the corporate governance of the Company, including director qualifications and responsibilities, responsibilities of key board committees, director compensation and similar matters. Each of the Audit Committee, the Management Development and Compensation Committee, and the Nominating and Corporate Governance Committee of the Board of Directors has adopted a written charter addressing various matters of importance relating to each committee, including the committee’s purposes and responsibilities, an annual performance evaluation of each committee and similar matters. These Corporate Governance Guidelines, and the charters of each of these committees, are available on the Company’s website at www.martinmarietta.com.

The Company’s Chief Executive Officer and Chief Financial Officer are required to file with the SEC each quarter and each year certifications regarding the quality of the Company’s public disclosure of its financial condition. The annual certifications are included as exhibits to this Form 10‑K. The Company’s Chief Executive Officer is also required to certify to the New York Stock Exchange each year that he is not aware of any violation by the Company of the New York Stock Exchange corporate governance listing standards.

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Part I ♦ Item 1A – Risk Factors

ITEM 1A – RISK FACTORS

An investment in Martin Marietta common stock or debt securities involves risks and uncertainties. You should consider the following factors carefully, in addition to the other information contained in this Form 10-K, before deciding to purchase or otherwise trade the Company’s securities.

This Form 10-K and other written reports and oral statements made from time to time by the Company contain statements that, to the extent they are not recitations of historical fact, constitute forward-looking statements within the meaning of federal securities law. Investors are cautioned that all forward-looking statements involve risks and uncertainties, and are based on assumptions that the Company believes in good faith are reasonable, but which may be materially different from actual results. Investors can identify these statements by the fact that they do not relate only to historic or current facts. The words “may,” “will,” “could,” “should,” “anticipate,” “believe,” “estimate,” “expect,” “forecast,” “intend,” “outlook,” “plan,” “project,” “scheduled,” and similar expressions in connection with future events or future operating or financial performance are intended to identify forward-looking statements. Any or all of the Company’s forward-looking statements in this Form 10‑K and in other publications may turn out to be wrong.

Statements and assumptions on future revenues, income and cash flows, performance, economic trends, the outcome of litigation, regulatory compliance, and environmental remediation cost estimates are examples of forward-looking statements. Numerous factors, including potentially the risk factors described in this section, could affect the Company's forward-looking statements and actual performance.

Investors are also cautioned that it is not possible to predict or identify all such factors. Consequently, the reader should not consider any such list to be a complete statement of all potential risks or uncertainties. Other factors besides those listed may also adversely affect the Company and may be material to the Company. The Company has listed the known material risks it considers relevant in evaluating the Company and its operations. The forward-looking statements in this document are intended to be subject to the safe harbor protection provided by Section 27A of the Securities Act of 1933 and Section 21E of the Exchange Act. These forward-looking statements are made as of the date hereof based on management’s current expectations, and the Company does not undertake an obligation to update such statements, whether as a result of new information, future events, or otherwise, other than as required by law.

For a discussion identifying some important factors that could cause actual results to vary materially from those anticipated in the forward-looking statements, see the factors listed below, along with the discussion of “Competition” under Item 1 of this Form 10-K, “Management’s Discussion and Analysis of Financial Condition and Results of Operations” under Item 7 of this Form 10-K, and “Note A: Accounting Policies” and “Note N: Commitments and Contingencies” of the “Notes to Financial Statements” of the Company’s consolidated financial statements included under Item 8, “Financial Statements and Supplemental Data,” of this Form 10-K.

Industry Risk Factors

Our business depends on activity within the construction industry, which can be cyclical.

Economic and political uncertainty can impede growth in the markets in which we operate. Demand for our products, particularly in the private nonresidential and residential construction markets, could decline if companies and consumers are unable to obtain credit for construction projects or if an economic slowdown causes delays or cancellations of capital projects. State and federal budget issues sometimes undermine the funding available for infrastructure spending. The lack of available credit may limit the ability of states to issue bonds to finance construction projects. As a result of these issues, several of our top revenue-generating states, from time to time, stop bidding or slow bid projects in their transportation departments.

We sell most of our aggregates (our primary business) and our cement products to the construction industry and, therefore, our results depend on that industry’s strength. Since our businesses depend on construction spending, which can be cyclical, our profits are sensitive to national, regional and local economic conditions and the intensity of the underlying spending on aggregates and cement products. Construction spending is affected by economic conditions, changes in interest rates, inflation, employment levels, demographic and population shifts, and changes in construction spending by federal, state and local governments. If economic conditions worsen, a recession in the construction industry may occur and affect the demand for our products. The recessions of the late 2000s and early 2010s (the Great Recession) were examples, and our shipment volumes were significantly reduced and remain below peak shipment levels, excluding the contribution of acquisitions. Construction spending can also be disrupted by terrorist activity and armed conflicts.

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Part I ♦ Item 1A – Risk Factors

While our business operations cover a wide geographic area, our earnings depend on the strength of the local economies in which we operate due to the high cost to transport our products relative to their selling price. If economic conditions and construction spending decline significantly in one or more areas, particularly in our Building Materials business’ top ten revenue-generating states of Texas, North Carolina, Colorado, California, Georgia, Minnesota, Arizona, Iowa, Florida and Indiana, our profitability will decrease. We experienced this situation during the Great Recession.

Demand for aggregates products, particularly in the infrastructure construction market, is affected by federal, state and local budget and deficit issues. Remote working trends or other factors that reduce vehicle miles driven can have a negative impact on various revenue streams that fund roadway projects. Further, delays or cancellations of projects in the nonresidential and residential construction markets, which combined accounted for 59% of aggregates shipments in 2023, could occur if companies and consumers are unable to obtain financing for construction projects or if consumer confidence continues to be eroded by economic uncertainty.

Our Building Materials business is seasonal and subject to the weather, which can significantly impact operations.

Since the heavy-side construction business is conducted outdoors, erratic weather patterns, seasonal changes and other weather-related conditions affect our business. Adverse weather conditions, including hurricanes and tropical storms, extreme temperatures, snow, heavy or sustained rainfall, wildfires and earthquakes, reduce construction activity, restrict the demand for our products and impede our ability to efficiently transport material. Adverse weather conditions also increase our costs and reduce our production output as a result of power loss, needed plant and equipment repairs, time required to remove water from flooded operations and similar events. Severe drought conditions can restrict available water supplies and restrict production. Production and shipment levels of the Building Materials business’ products follow activity in the construction industry, which typically is strongest in the spring, summer and fall. Because of the weather’s effect on the construction industry’s activity, the production and shipment levels for our Building Materials business, including all of our aggregates-related downstream operations, vary by quarter. The second and third quarters are generally subject to heavy precipitation, and thus are more profitable if precipitation is lighter. The first and fourth quarters, which are subject to the impacts of winter weather, are generally the least profitable, but can be more profitable if the impact of winter weather is less. Our operations in the Atlantic and Gulf Coast regions of the United States and The Bahamas are at risk for hurricane activity, most notably in August, September and October. Our California operations are at risk for Pacific Ocean storms, wildfire activity and water use restrictions in the event of severe drought conditions. These weather events and conditions may be exacerbated by climate change in the near and long term.

Competition and Growth Risk Factors

Our Building Materials business depends on the availability of quality aggregates reserves or deposits and our ability to mine them economically.

Our challenge is to find quality aggregates deposits that we can mine economically, with appropriate permits, near either growing markets or long-haul transportation corridors that economically serve applicable markets. As communities in many of our geographic markets have grown, they have settled in and around attractive quarrying locations and have imposed restrictions on mining. We try to meet this challenge by identifying and permitting sites prior to economic expansion, buying more land around our existing quarries to increase our mineral reserves, developing underground mines and expanding a distribution network that transports aggregates products by various methods, including rail and water. While our distribution network allows us to transport our products longer distances than would normally be considered economical, we can give no assurances that we will be successful at this strategy.

Our businesses face many competitors.

Our businesses have many competitors, some of whom are bigger and have more resources than we do. Some of our competitors operate on a worldwide basis. Our results are affected by the number of competitors in a market, the production capacity that a particular market can accommodate, the pricing practices of other competitors and the entry of new competitors in a market. We also face competition for some of our products from alternative products. For example, our Magnesia Specialties business competes with other chemical products that could be used instead of our magnesia-based products. As other examples, our aggregates, ready mixed concrete, asphalt and paving businesses compete with recycled asphalt and concrete products that could be used in certain applications instead of new products and our cement operations

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Part I ♦ Item 1A – Risk Factors

compete with international competitors who import products into the United States from jurisdictions with lower production and regulatory costs and burdens.

Our future growth depends in part on acquiring other businesses in our industry, and we have the ability to acquire businesses by paying all or in part with shares of our common stock.

We expect to continue to grow, in part, by acquiring other businesses. In the past, we have made acquisitions to strengthen our existing locations, expand our operations and enter new geographic markets. We will continue to pursue selective acquisitions, joint ventures or other business arrangements we believe will help our Company grow. However, the continued success of our acquisition program will depend on our ability to find and buy other attractive businesses at an appropriate price and our ability to integrate acquired businesses into our existing operations. We cannot assume there will continue to be attractive acquisition opportunities for sale at reasonable prices that we can successfully integrate into our operations.

We have the ability to pay all or part of the purchase price of any future acquisition with shares of our common stock. We also have the ability to use our stock to make strategic investments in other companies to complement and expand our operations. If we use our common stock in this way, the ownership interests of our existing shareholders at that time will be diluted and the price of our stock could decline. We operate our businesses with the objective of maximizing long-term shareholder return.

Our integration of the acquisition or business combination with other businesses may not be as successful as projected.

We have a successful history of business combinations and integration of these businesses into our heritage operations. However, in connection with the integration of any other business that we acquire, there is a risk that we will not be able to achieve such integration in a successful manner or on the time schedule we have projected or in a way that will achieve the level of synergies, cost savings or operating efficiencies we forecast from the acquisition.

Any significant business acquisition or combination we might choose to undertake may require that we devote significant management attention and resources to preparing for and then integrating our business practices and operations. Based on our history, we believe we would be successful in this integration process. Nevertheless, we may fail to realize some of the anticipated benefits of any potential acquisition or other business combination that we pursue in the future if the integration process takes longer or is more costly than expected. Potential difficulties we may encounter in the integration process include the following:

inability to successfully combine operations in a manner that permits us to achieve the synergies anticipated to result from the proposed acquisition or business combination, which would result in the anticipated benefits of the acquisition or business combination not being realized partly or wholly in the time frame currently anticipated or at all;

lost sales and customers as a result of certain customers of either the Company or former customers of the acquired or combined company deciding not to do business with us;

complexities associated with managing the combined operations;

integration of personnel;

creation of uniform standards, internal controls, procedures, policies and information systems;

discovery of previously unknown liabilities and unforeseen increased expenses, delays or regulatory issues associated with integrating the remaining operations; and

performance shortfalls at business units as a result of the diversion of management attention caused by completing the remaining integration of the operations.

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Part I ♦ Item 1A – Risk Factors

Our acquisitions and divestitures could harm our results of operations.

In pursuing our business strategy, we conduct discussions, evaluate opportunities and enter into acquisition and divestiture agreements. Acquisitions involve significant challenges and risks, including risks that:

we may not realize a satisfactory return on our investment;

we may not obtain required regulatory approvals and/or required financing on favorable terms;

we may not be able to retain key personnel of acquired businesses;

we may experience difficulty in integrating new employees, business systems and technology;

our due diligence process may not identify compliance issues or other liabilities that are in existence at the time of our acquisition;

we may not be able to bring the acquired business up to our expected levels of safety standards as soon as anticipated;

we may have difficulty entering into new geographic markets in which we are not experienced; or

we may be unable to retain the customers and partners of acquired businesses following the acquisition.

Divestitures also involve significant challenges and risks, including risks that:

we may not obtain required regulatory approvals or our counterparties may not obtain required financing on favorable terms;

management time and attention may be diverted in businesses held for sale;

we may have to write-off certain assets, including those relating to goodwill and other intangibles;

we may experience difficulties in the separation of operations; and

we may lose key employees.

Our cement and Magnesia Specialties businesses may become capacity-constrained.

If our cement or Magnesia Specialties businesses becomes and/or remains capacity-constrained, we may be unable to timely satisfy the demand for some of our products, and any resulting changes in customers would introduce volatility to the earnings of these segments. We can address capacity needs by enhancing our manufacturing productivity, increasing the operational availability of equipment, reducing machinery down time and extending machinery useful life. Future demand for our products may require us to expand our manufacturing capacity further, particularly through the purchase of additional manufacturing equipment. However, we may not be able to increase our capacity in time to satisfy increases in demand that may occur from time to time. Our Texas cement operations are currently capacity constrained, which may prevent us from satisfying customer orders and result in a loss of sales to competitors that are not capacity-constrained. We are permitted to expand production by up to 0.8 million additional tons at our Midlothian cement facility and are currently in the process of effecting an expansion to add 0.5 million tons of annual production capacity. However, we may suffer excess capacity if we increase our capacity to meet actual or anticipated demand and that demand decreases or does not materialize.

Our cement business could suffer if cement or clinker imports from other countries significantly increase or are sold in the United States in violation of U.S. fair trade laws.

In the past, the cement industry has benefited from antidumping orders imposing duties on imports of cement and clinker from other countries that violated U.S. fair trade laws. Cement operators with import facilities can purchase cement from other countries, such as those in Latin America and Asia, which could compete with domestic producers. In addition, if environmental regulations increase the costs of domestic producers compared to foreign producers that are not subject to similar regulations, imported cement could achieve a significant cost advantage over domestically produced cement. An influx of cement or clinker products from countries not subject to antidumping orders, or sales of imported cement or clinker in violation of U.S. fair trade laws, could adversely affect our cement product line.

Form 10-K ♦ Page 17

Part I ♦ Item 1A – Risk Factors

Economic, Political and Legal Risk Factors

Changes in legal requirements and governmental policies concerning zoning, land use, the environment, health and safety and other areas of the law, as well as litigation relating to these matters, affect our businesses. Our operations expose us to the risk of material environmental liabilities.

Many federal, state and local laws and regulations relating to zoning, land use, air emissions (including carbon dioxide and other greenhouse gases), water use, allocation and discharges, waste management, noise and dust control, mining, land reclamation and other environmental, health and safety matters govern our operations. Some of our operations require permits, which may impose additional operating standards and are subject to modification, renewal and revocation. Certain of our operations may from time to time involve the use of substances that are classified as toxic or hazardous within the meaning of these laws and regulations. Despite our extensive efforts to remain in strict compliance at all times with all applicable laws and regulations, the risk of liabilities, particularly environmental liabilities, is inherent in the operation of our businesses. These potential liabilities could result in material costs, including fines or personal injury or damages claims, which could have an adverse impact on our operations and profitability.

Future events, including changes in existing laws or regulations or enforcement policies, or further investigation or evaluation of the potential health hazards of some of our products or business activities may result in additional or unanticipated compliance and other costs. We could be required to invest in preventive or remedial action, like pollution control facilities, which could be substantial or which could result in restrictions on our operations or delays in obtaining required permits or other approvals.

Our operations are subject to manufacturing, operating and handling risks associated with the products we produce and the products we use in our operations, including the related storage and transportation of raw materials, explosives, products, hazardous substances and wastes. We are exposed to hazards, including storage tank leaks, explosions, discharges or releases of hazardous substances, exposure to dust, and the operation of mobile equipment and manufacturing machinery.

These risks can subject us to potentially significant liabilities relating to personal injury, death or property damage, and may result in significant civil or criminal penalties, which could hurt our productivity or profitability. For example, from time to time, we investigate and remediate environmental contamination relating to our prior or current operations, as well as operations we have acquired from others, and, in some cases, we have been or could be named as a defendant in litigation brought by governmental agencies or private parties to investigate or clean up such contamination.

We are involved from time to time in litigation and claims arising from our operations. While we do not believe the outcome of pending or threatened litigation will have a material adverse effect on our operations or our financial condition, an unexpected and material adverse outcome in a pending or future legal action could potentially have a negative effect on our Company.

Legislation or regulations to address climate change and transition to a low-carbon economy may adversely impact our business, including financial impacts.

A number of governmental bodies, including the U.S. Congress and various U.S. states, have proposed, enacted or are contemplating legislative and regulatory changes to mitigate or address the potential impacts of climate change, including provisions for greenhouse gas (GHG) emissions reductions or the use of alternative fuels, carbon credits (such as a cap-and-trade system) and a carbon tax. For example, in the United States, the United States Environmental Protection Agency (USEPA) promulgated a mandatory reporting rule covering GHG emissions from sources considered to be large emitters. Our cement plants, as well as our Magnesia Specialties plants, are strictly regulated with respect to GHG emissions and hold Title V Permits under USEPA regulations, and each (other than the Manistee Michigan facility) is also subject to the U.S. Clean Air Act’s Prevention of Significant Deterioration (PSD) requirements which require a permit program for certain new or modified sources of emissions. If future modifications to our Magnesia Specialties or cement facilities require PSD review for other pollutants, GHG permitting requirements may also be triggered, which could require us to incur significant additional costs. It is not possible, however, to estimate the cost of any future requirements at this time.

In 2021, a pair of executive orders and a presidential memorandum were issued making climate change central to U.S. policy and setting out several administrative priorities and undertakings to reduce GHG emissions. The United States reentered the Paris Agreement in January 2021 and later announced the U.S. reduction commitments under the Paris Agreement, including a 50% to 52% economy-wide reduction in net GHG emissions from 2005 levels by 2030. The United States has also entered a

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Part I ♦ Item 1A – Risk Factors

pact with 103 countries and jurisdictions, known as the Global Methane Pledge, to reduce global methane emissions by 30% from 2020 levels by the end of the decade. Although it is impossible to determine the actions the federal government will ultimately take to implement these or other orders, commitments and laws, or the full scope, timing or ramifications of such measures, the United States, like other signatories to the Paris Agreement, is currently pursuing a goal of a Net Zero GHG by 2050. It is also possible that the USEPA and other agencies will use their rule-making authority and procurement decisions to further address climate change. Various states where we have operations have enacted or are considering climate change initiatives as well, and we have been and may continue to be subject to state regulations in addition to any federal laws and rules that are passed. For example, California has had a cap-and-trade program for emissions rights since 2012. In addition, in October 2023, California adopted its California Climate Accountability Package which includes annual reporting of Scope 1, Scope 2 and Scope 3 emissions on a phased-in implementation schedule, climate-related risk reporting for certain companies and heightened disclosure standards around net zero emissions claims, carbon-neutral claims or significant GHG emissions reduction claims and the purchase or use of voluntary carbon offsets used to achieve those claims. These and other state climate-related regulations may result in significantly higher compliance costs and risks.

In addition, although our aggregates, ready mixed concrete, asphalt and paving operations are not considered “major” sources of GHG emissions subject to the USEPA reporting rule, any additional regulatory restrictions on emissions of GHGs imposed by the USEPA would likely impact our magnesia-based chemicals operations in Woodville, Ohio, and Manistee, Michigan, as well as our cement operations in Texas, which in 2023 filed annual reports of GHG emissions as required by the USEPA reporting rule. We may not be able to recover any increased operating costs, taxes or capital investments (other than with respect to any carbon reduction or capture technologies) relating to GHG emission limitations at those plants from our customers in order to remain competitive in pricing in the relevant markets. Our businesses also are dependent on reliable sources of energy and fuels. We could incur increased costs or disruptions in our operations if climate change legislation and regulation (including regulatory changes with respect to alternative fuel use) or severe weather affect the price or availability of purchased energy or fuels or other materials used in our operations.

While we do not currently believe such requirements will have a material adverse effect on the financial condition or results of the operations of either the Magnesia Specialties business or Building Materials business, in light of the various regulatory uncertainties, it is very difficult at this time to reasonably predict the costs of any future compliance requirements. We continue to monitor GHG regulations and legislation and its potential impact on our business, financial condition and product demand.

Climate change may result in physical impacts that could have adverse effects on our operations or financial condition.

Given the nature of our operations, physical impacts may include disruptions in production, regional supply or product distribution networks, as well as negative impacts on the price or availability of purchased energy or fuels, due to major storm events or other severe weather, shifts in regional rainfall and temperature patterns and intensities, and flooding from sea level changes. In addition, production and shipment demand for our Building Materials business correlate with general construction activity and rely on road, rail and water transportation networks, most of which occurs outdoors and, as a result, is affected by erratic weather patterns, seasonal changes and other unusual or unexpected weather-related conditions, which can significantly affect that business. In our cement and downstream businesses, the physical impacts of climate change may result in disruptions to our operations and to our customers’ transportation activities, including impacts on production capabilities and capacities, supply chain interruptions and project delays, which can impact our reputation and result in additional costs to our Company. Excessive rainfall and other severe weather events also jeopardize production, shipments and profitability in all markets served by our Building Materials business. In particular, our operations in the Atlantic and Gulf Coast regions of the United States and The Bahamas are at risk for hurricane activity, most notably in August, September and October. In addition, our California operations are at risk for wildfires, which is exacerbated by drought, which may also result in water restrictions, while recent unprecedented storms and flooding have caused operational delays and challenges. Increased intensity and frequency of extreme weather events have been linked to climate change, and further global warming may increase the risk of adverse weather conditions. Climate and inclement weather can also reduce the useful life of an asset. These and other climate-related risks, such as a downturn in the construction sector due to harsh weather, significant precipitation or other changes in weather, could impact our customers, which could lead to reduced demand for our products. We may not be able to pass on to our customers all the costs related to mitigating these risks.

Form 10-K ♦ Page 19

Part I ♦ Item 1A – Risk Factors

Our business is dependent on funding from a combination of federal, state and local sources.

Our products are used in public infrastructure projects, which include the construction, maintenance and improvement of highways, streets, roads, bridges, schools and similar projects. Accordingly, our business is dependent on the level of federal, state and local spending on these projects. We cannot be assured, however, of the amount and timing of appropriations for spending on infrastructure projects.

Our businesses could be impacted by rising interest rates.

Our operations are highly dependent upon the interest rate-sensitive construction and steelmaking industries. Therefore, our business in these industries may decline from rising interest rates and cost increases.

Notably, demand in the residential construction market in which we sell our aggregates products is affected by interest rates. The Federal Reserve raised interest rates throughout 2023 to attempt to address high inflation. Sustained high interest rates may affect our business in an adverse manner. The residential construction market accounted for 24% of our 2023 aggregates shipments.

Aside from these inherent risks from within our operations, our earnings are also affected by changes in short-term interest rates. However, rising interest rates are not necessarily predictive of weaker operating results.

Rising interest rates could also result in disruptions in the credit markets, which could affect our business, as described in greater detail under Disruptions in the credit markets could affect our business risk factor.

Increases in our effective income tax rate may harm our results of operations.

A number of factors may increase our future effective income tax rate, including:

governmental authorities increasing taxes or eliminating deductions, particularly the depletion deduction;

the mix of earnings from depletable versus non-depletable businesses;

the jurisdictions in which earnings are taxed;

the resolution of issues arising from tax audits with various tax authorities;

changes in the valuation of our deferred tax assets and liabilities;

adjustments to estimated taxes upon finalization of various tax returns;

changes in available tax credits;

changes in stock-based compensation;

the write-off of nondeductible goodwill resulting from divestitures;

other changes in tax laws; and

the interpretation of tax laws and/or administrative practices.

The Infrastructure Investment and Jobs Act imposes a minimum corporate income tax rate of 15% on companies with at least $1 billion of pretax earnings. Any significant increase in our future effective income tax rate could reduce our net earnings and free cash flow for future periods.

Climate change and sustainability matters and any related reporting obligations may impact our businesses.

Investors, other stakeholders, and U.S. and international regulators are often focused on climate change and sustainability matters. For example, new proposed U.S. laws and regulations relating to and requiring disclosure of such matters, including those relating to sustainability, climate change, supply chain, human capital and diversity, are under consideration or being adopted, or may be proposed in the future. These requirements have resulted in and may continue to result in our need to make additional investments and implement new practices and reporting processes, all entailing management attention and additional compliance risk. Any failure or perceived failure to achieve or accurately report on our current or future climate-related commitments, including our GHG reduction and net zero targets, and any differences between our commitments and those of any companies to which we are compared, could harm our reputation, adversely affect our ability to effectively compete (including as a result of disclosure of proprietary information regarding our plants or changes in our ability to raise capital), adversely affect our recruitment and retention efforts or expose us to potential legal liability. In addition, while we are

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Part I ♦ Item 1A – Risk Factors

committed to pursuing our sustainability objectives, there is no assurance that we will achieve any of our sustainability goals or commitments, that low- or non-carbon-based energy sources and technologies required to meet long-term emissions reductions in some of the sectors in which we operate will be available at scale in the United States on an economically feasible basis or that our suppliers can meet sustainability, diversity and other standards that are required by current or future laws or established as investment criteria, voting guidelines or activism triggers by our investors and other stakeholders. Failure to meet these commitments could result in reputational harm to our Company and changes regarding climate risk management and practices may result in higher regulatory and compliance risks and costs.

Our businesses could be adversely affected by outbreak of disease, epidemic or pandemic, or similar public health threat, or fear of such an event and its related economic and societal response.

Our businesses could be negatively impacted by the widespread outbreak of an illness or other communicable disease, or any other public health crisis that results in economic and trade disruptions. Public health threats can negatively impact economic activity, consumer confidence and discretionary spending, and overall market conditions and these conditions could have an impact on our Company to the extent that they occur in regions where our Building Materials business principally operates. Further, outbreaks of illnesses could negatively affect the health of our employees, employee productivity, customer purchasing patterns and fulfillment of purchase orders, availability of supplies, pricing for raw materials and the ability to transport materials via the Company’s distribution network. We actively monitor public health situations as part of our health and safety measures and acted during the COVID-19 pandemic to comply with federal, state and local mandates and to protect the health and safety of our employees. We may take further actions that alter our business operations, including any that may be required by federal, state or local authorities or that we determine are in the best interests of our employees, customers, suppliers, vendors, communities and other stakeholders as we adapt to public health events from time to time.

Personnel Risks

Labor disputes could disrupt operations of our businesses.

Labor unions represent 14% of the hourly employees of our Building Materials business and all of the hourly employees of our Magnesia Specialties business. Our collective bargaining agreements for employees of our Magnesia Specialties business at the Woodville, Ohio, lime plant and the Manistee, Michigan magnesia chemicals plant expire in June 2026 and August 2027, respectively.

Disputes with our trade unions, or the inability to renew our labor agreements, could lead to strikes or other actions that could disrupt our businesses, raise costs and reduce revenues and earnings from the affected locations.

We depend on the recruitment and retention of qualified personnel, and our failure to attract and retain such personnel could adversely affect our business.

Our success depends to a significant degree upon the continued services of, and on our ability to attract and retain, our key personnel and executive officers, including qualified management, technical, marketing and sales, and support personnel. Competition for such personnel is intense, and we may not be successful in attracting or retaining such qualified personnel, which could negatively affect our business. In addition, because of our reliance on our senior management team, the unanticipated departure of any key member could have an adverse effect on our business. Our future success depends, in part, on our ability to identify and develop or recruit talent to succeed our senior management and other key positions throughout the organization. If we fail to identify and develop or recruit successors, we are at risk of being harmed by the departures of these key employees. Effective succession planning is also important to our long-term success. Failure to ensure effective transfer of knowledge and smooth transitions involving key employees could hinder our strategic planning and execution.

Investment returns on our pension assets may be lower than expected, or interest rates may decline, requiring us to make significant additional cash contributions to our benefit plans.

A portion of our current and former employees has accrued benefits under our defined benefit pension plans. Requirements for funding our pension plan liabilities are based on a number of actuarial assumptions, including the expected rate of return on our plan assets and the discount rate applied to our pension plan obligations. Fluctuations in equity market returns and changes in long-term interest rates could increase our costs under our defined benefit pension plans and may significantly affect future contribution requirements. It is unknown what the actual investment return on our pension assets will be in future years and what interest rates may be at any given point in time. We cannot therefore provide any assurance of what our actual

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Part I ♦ Item 1A – Risk Factors

pension plan costs will be in the future, or whether we will be required under applicable law to make future material plan contributions.

Our reputation, ability to do business and results of operations could be impaired by improper conduct by any of our employees, agents or business partners.

We are subject to regulation under a wide variety of U.S. federal and state and some non-U.S. laws, regulations and policies, including laws related to anticorruption, antibribery, export and import compliance, antitrust and money laundering, due to our operations. We cannot provide assurance that our compliance policies and internal controls will always protect us from the improper conduct of our employees, agents and business partners. Any violations of law or improper conduct could damage our reputation and, depending on the circumstances, subject us to, among other things, civil and criminal penalties, material fines, equitable remedies (including profit disgorgement and injunctions on future conduct), securities litigation and a general loss of investor confidence, any one of which could have a material adverse impact on our business prospects, financial condition, results of operations, cash flows and the market value of our stock.

Financial, Accounting and Cost Management Risk Factors

Our business is a capital-intensive business.

The property and machinery needed to produce our products are very expensive. Therefore, we require large amounts of cash to operate our businesses. We believe that our cash on hand, along with our projected operating cash flows and our available financing resources, is adequate to support our anticipated operating and capital needs. Our ability to generate sufficient cash flow depends on future performance, which will be subject to general economic conditions, industry cycles and financial, business and other factors affecting our operations, many of which are beyond our control. If we are unable to generate sufficient cash to operate our business, we may be required, among other things, to reduce or delay planned capital or operating expenditures.

Our earnings are affected by the application of accounting standards and our critical accounting policies, which involve subjective judgments and estimates by our management. Our estimates and assumptions could be wrong.

The accounting standards we use in preparing our financial statements are often complex and require that we make significant estimates and assumptions in interpreting and applying those standards. These estimates and assumptions involve matters that are inherently uncertain and require our subjective and complex judgments. If we used different estimates and assumptions or used different ways to determine these estimates, our financial results could differ.

While we believe our estimates and assumptions are appropriate, we could be wrong. Accordingly, our financial results could be different, either higher or lower. We urge you to read "Critical Accounting Policies and Estimates" included under Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” of the Form 10-K.

The adoption of new accounting standards may affect our financial results.

The accounting standards we apply in preparing our financial statements are reviewed by regulatory bodies and are periodically changed. New or revised accounting standards could, either positively or negatively, affect results reported for periods after adoption of the standards as compared with the prior periods, or require retrospective application changing results reported for prior periods. We urge you to read about our accounting policies and new accounting pronouncements in Note A: Accounting Policies of our consolidated financial statements included under Item 8, “Financial Statements and Supplementary Data,” of this Form 10-K.

Reports from the Public Company Accounting Oversight Board’s (PCAOB) inspections of public accounting firms continue to outline findings and recommendations that could require these firms to perform additional work as part of their financial statement audits. Our costs to respond to these additional requirements may increase.

Impairment charges could have a material adverse effect on our financial results.

Goodwill and other acquired intangible assets expected to contribute indefinitely to our cash flows are not amortized, but must be evaluated for impairment by management at least annually. If the carrying value of a reporting unit exceeds its fair value, the reporting unit's goodwill is considered impaired and a non-cash charge to earnings is recorded for the difference. If the

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Part I ♦ Item 1A – Risk Factors

carrying value of an indefinite-lived intangible asset is greater than its fair value, the intangible asset is considered impaired and is reduced to fair value via a non-cash charge to earnings. Future events may occur that would adversely affect the fair value of our goodwill or other acquired intangible assets and require impairment charges. Such events may include, but are not limited to, lower-than-forecasted revenues, construction growth rates that fall below our assumptions, actions of key customers, increases in discount rates, continued economic uncertainty, higher levels of unemployment, weak consumer confidence, lower levels of discretionary consumer spending and a decline in the trading price of our common stock. We continue to evaluate the impact of economic and other developments to assess whether impairment indicators are present. Accordingly, we may be required to perform impairment tests based on changes in the economic environment and other factors, and these tests could result in impairment charges in the future.

Disruptions in the credit markets could affect our business.

We have considered the current economic environment and its potential impact to our business. Demand for aggregates products, particularly in the infrastructure construction market, has historically been negatively affected by federal and state budget challenges and the uncertainty over future highway funding levels. Further, delays to or cancellations of capital projects in the nonresidential and residential construction markets could occur if companies and consumers are unable to obtain financing for construction projects or if consumer confidence is eroded by economic uncertainty.

A recessionary construction economy can also increase the likelihood we will not be able to collect all our accounts receivable from our customers. While we are protected in part by payment bonds posted by many of our customers or end-users, as well as statutory lien rights, we have experienced delays in payment from some of our customers during construction downturns and expect that we would experience such delays in the future which would negatively affect operating cash flows.

The credit environment could impact our ability to borrow money in the future. Additional financing or refinancing might not be available and, if available, may not be at economically favorable terms. Further, an increase in leverage could lead to deterioration in our credit ratings. A reduction in our credit ratings, regardless of the cause, could also limit our ability to obtain additional financing and/or increase our cost of obtaining financing. There is no guarantee we will be able to access the capital markets at financially economical interest rates, which could negatively affect our business.

We may be required to obtain financing in order to fund certain strategic acquisitions, if they arise, or to refinance our outstanding debt. It is possible a large strategic acquisition would require that we issue new equity and debt securities in order to maintain our investment-grade credit rating and could result in a ratings downgrade notwithstanding our issuance of equity securities to fund the transaction. We are also exposed to risks from tightening credit markets, through the interest payable on any variable-rate debt, including the interest cost on future borrowings under our credit facilities. While we believe our credit ratings will remain at a composite investment-grade level, we cannot be assured these ratings will remain at those levels. Also, while we believe our Company will continue to have adequate credit available to meet its needs, there can be no assurance of that.

Our Magnesia Specialties business faces currency risks from its overseas activities.

Our Magnesia Specialties business sells some of its products outside the United States. Therefore, the operations of the Magnesia Specialties business are affected from time to time by the fluctuating values of the currency exchange rates of the countries in which it does business in relation to the value of the U.S. Dollar. The business tries to mitigate the short-term effects of currency exchange rates by primarily denominating sales in the U.S. Dollar. This still leaves the business subject to certain risks, depending on the strength of the U.S. Dollar.

Unexpected equipment failures, catastrophic events and scheduled maintenance may lead to production curtailments or shutdowns.

Our manufacturing processes are dependent upon critical pieces of equipment, such as our kilns and finishing mills. This equipment, on occasion, is out of service as a result of planned or unplanned maintenance, failures or damage during accidents. In addition to equipment failures, our facilities are also subject to the risk of catastrophic loss due to unanticipated events, such as fires, explosions or violent weather conditions. We have scheduled outages that can range from one to several weeks at least once a year to refurbish our cement and dolomitic lime production facilities. In 2023, our cement and Magnesia Specialties operations incurred shutdown costs of $38.4 million and $9.9 million, respectively. Any significant interruption in production capability may require us to make significant capital expenditures to remedy problems or damage as well as cause us to lose revenue due to lost production time.

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Part I ♦ Item 1A – Risk Factors

Our paving operations present additional risks to our business.

Our paving operations face challenges when our contracts have penalties for late completion. In some instances, including many of our fixed-price contracts, we guarantee project completion by a certain date. If we subsequently fail to complete the project as scheduled, we may be held responsible for costs resulting from the delay, generally in the form of contractually agreed-upon liquidated damages. Under these circumstances, the total project cost could exceed our original estimate, and we could experience a loss of profit or a loss on the project. In our paving operations, we also have fixed-price and fixed-unit-price contracts where our profits can be adversely affected by a number of factors beyond our control, which can cause our actual costs to materially exceed the costs estimated at the time of our original bid. These same issues and risks can also impact some of our contracts in our asphalt and ready mixed concrete operations. These risks are somewhat mitigated by the fact that a majority of our road paving contracts are for short-term projects.

Our ready mixed concrete and asphalt and paving product lines have lower profit margins and operating results can be more volatile.

Our ready mixed concrete and asphalt and paving operations typically generate lower profit margins than our aggregates and cement operations due to potentially volatile input costs, highly competitive market dynamics and lower barriers to entry. To reduce our exposure to fluctuations in raw materials costs, we divested our ready mixed concrete operations in Colorado and Central Texas in 2022. Additionally, on February 9, 2024, we sold 20 ready mixed concrete plants serving the Austin and San Antonio, Texas, region.

Suppliers, Raw Materials and Energy Costs Risk Factors

Short supplies and high costs of fuel, energy and raw materials affect our businesses.

Our businesses require a continued supply of diesel fuel, natural gas, coal, petroleum coke and other energy. Our financial results have historically been affected by the short supply or high costs of these fuels and energy. Changes in energy costs also affect the prices that we pay for related supplies, including explosives, conveyor belting and tires. While we can contract for some fuels and sources of energy, such as fixed-price supply contracts for natural gas, coal and petroleum coke, significant increases in costs or reduced availability of these items have and may in the future reduce our financial results. Moreover, fluctuations in the supply and costs of these fuels and energy can make planning for our businesses more difficult. Because of the fluctuating trends in diesel fuel prices, we may enter into fixed-price fuel agreements from time to time for a portion of our diesel fuel to reduce our diesel fuel price risk.

Cement production requires large amounts of energy, including electricity and fossil fuels. Energy costs represented 18% of the 2023 total cost of revenues, excluding inventory change, for our cement operations. Therefore, the cost of energy is one of our largest expenses. Prices for energy are subject to market forces largely beyond our control and can be volatile. Cost increases that we are unable to pass through to the customer in the form of price increases for our products or disruption of the uninterrupted supply of fuel and electricity could adversely affect us. Accordingly, energy cost volatility can adversely affect the financial results of our cement operations. The cement operations have fixed-price agreements for a portion of their 2024 coal, electricity and natural gas needs.

Similarly, our downstream operations also require a continued supply of liquid asphalt and cement, which serve as key raw materials in the production of hot mix asphalt and ready mixed concrete, respectively. Some of these raw materials we produce internally, but most are purchased from third parties. These purchased raw materials are subject to potential supply constraints and significant price fluctuations, which are beyond our control. The financial results of our ready mixed concrete and asphalt and paving operations have been affected by the short supply or high costs of these raw materials. We generally see frequent volatility in the prices for these raw materials.

Our Magnesia Specialties business has fixed-price agreements for 81% of its 2024 coal, petroleum coke and natural gas needs.

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Part I ♦ Item 1A – Risk Factors

Cement is sensitive to supply and price volatility.

Cement competition is often based primarily on price, which is highly sensitive to changes in supply and demand. Prices fluctuate significantly in response to relatively minor changes in supply and demand, general economic conditions and other market conditions, which we cannot control. When cement producers increase production capacity or more cement is imported into the market, an oversupply of cement in the market may occur if supply exceeds demand. In that case, cement prices generally decline. We cannot be assured that prices for our cement products sold will not decline in the future or that such decline will not have a material adverse effect on our cement product line.

Our Magnesia Specialties business depends in part on the steel industry and the supply of reasonably priced fuels.

Our Magnesia Specialties business sells some of its products to companies in the steel industry. While we have reduced this risk over the last few years, this business is still dependent, in part, on the strength of the cyclical steel industry. Our Magnesia Specialties business also requires significant amounts of natural gas, coal and petroleum coke, and financial results are negatively affected by increases in fuel prices or shortages.

Cyber and Information Security Risk Factors

We are dependent on information technology and our systems and infrastructure face certain risks, including cybersecurity risks and data leakage risks.

Our operations rely on the secure processing, storage and transmission of confidential, sensitive, proprietary and other types of information relating to our business operations, as well as confidential and sensitive information about our customers and employees maintained in our computer systems and networks, certain products and services and in the computer systems and networks of our third-party vendors, including cloud-based systems and managed service providers. Cyber threats are rapidly evolving as threat actors have become increasingly sophisticated and carry out direct large-scale, complex attacks against a company. In addition, we have relied on our information technology infrastructure to support remote work from time to time and may need to do so in the future, which can increase cyber risks. We are not able to anticipate or prevent all such attacks and could be held liable for any resulting material security breach or data loss. In addition, it is not always possible to deter misconduct by employees or third-party vendors.

While we have experienced attacks to breach the security of our information technology systems, we are not aware that we have experienced a material cybersecurity incident during the 2023 fiscal year. Breaches of our technology systems, or those of our vendors and customers, whether from circumvention of security systems, denial-of-service attacks or other cyber-attacks, hacking, “phishing” or "quishing" attacks, computer viruses, ransomware or malware, employee or insider error, malfeasance, social engineering, vendor software supply chain compromises, physical breaches or other actions, may result in manipulation or corruption of sensitive data, material interruptions or malfunctions in our Company’s or such vendors’ and customers’ websites, applications, data processing and certain products and services, or disruption of other business operations. Furthermore, any such breaches could compromise the confidentiality and integrity of material information held by our Company (including information about our business, employees or customers), as well as sensitive personally identifiable information, the disclosure of which could lead to identity theft. Breaches of our products that rely on technology and internet connectivity can expose our Company to product and other liability risk and reputational harm. Measures that we take to avoid, detect, mitigate or recover from material incidents, may be insufficient, circumvented, or may become ineffective.

We have invested and continue to invest in risk management and information security and data privacy measures in order to protect our systems and data, including employee training, organizational investments, incident response plans, table top exercises and technical defenses. The cost and operational consequences of implementing, maintaining and enhancing further data or system protection measures could increase significantly to overcome increasingly intense, complex and sophisticated global cyber threats. Despite our best efforts, we are not fully insulated from data breaches and system disruptions. In addition, we are subject to complex and evolving laws, rules and regulations related to cybersecurity. These laws or regulations may be subject to uncertain or inconsistent interpretations and enforcement.

Any material breaches of cybersecurity, including the accidental loss, inadvertent disclosure or unapproved dissemination of proprietary information or sensitive or confidential data, or failure or perceived failure by us to comply with applicable laws, rules, or regulations, or any media reports of perceived security vulnerabilities to our systems, products and services or those

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Part I ♦ Item 1A – Risk Factors

of third parties relied upon by our Company could cause us to experience reputational harm, loss of customers and revenue, fines, regulatory actions and scrutiny, sanctions or other statutory penalties, litigation, liability for failure to safeguard our customers’ information or financial losses that are either not insured against or not fully covered through any insurance maintained by our Company. The report, rumor or assumption regarding a potential breach may have similar results, even if no breach has been attempted or occurred. Any of the foregoing may have a material adverse effect on our business, operating results and financial condition.

We are exposed to risks related to compliance with data privacy laws.

To conduct certain of our operations, we move data across national borders, and consequently are subject to a variety of continuously evolving and developing laws and regulations in the United States and abroad regarding privacy, data protection and data security. The scope of the laws that may be applicable to our business is often uncertain and may be conflicting, particularly with respect to foreign laws. The California Consumer Privacy Act of 2018 (CCPA), which went into effect in January 2020, provides, among other things, a new private right of action for data breaches, requires companies that process information on California residents to make new disclosures to consumers about their data collection, use and sharing practices, and provides consumers with additional rights. The California Privacy Rights and Enforcement Act, which became effective on January 1, 2023, amends and expands the CCPA, creating new industry requirements, consumer privacy rights and enforcement mechanisms. In addition, the European Union’s General Data Protection Regulation (GDPR), which became effective in May 2018, greatly increased the jurisdictional reach of European Union law and added a broad array of requirements for handling personal data, including the public disclosure of significant data breaches. Our reputation and brand and our ability to attract new customers could also be adversely impacted if we fail, or are perceived to have failed, to properly respond to security breaches of ours or third party’s information technology systems. Such failure to properly respond could also result in similar exposure to liability.

All of these evolving compliance and operational requirements impose significant costs that are likely to increase over time. Privacy laws that may be implemented in the future will continue to require changes to certain business practices, thereby increasing costs, or may result in negative publicity, require significant management time and attention, and may subject our Company to remedies that may harm our business, including fines or demands or orders that we modify or cease existing business practices.

Other Risk Factors

Delays or interruptions in shipping products of our businesses could affect our operations.

Transportation logistics play an important role in allowing us to supply products to our customers, whether by road, rail or water. We also rely heavily on third-party truck and rail transportation to ship coal, natural gas and other fuels to our plants. Any significant delays, disruptions or the non-availability of our transportation support system could negatively affect our operations. Transportation operations are subject to capacity constraints, high fuel costs and various hazards, including extreme weather conditions and slowdowns due to labor strikes and other work stoppages. In Texas, we compete for third-party trucking services with operations in the oil and gas fields, which can significantly constrain the availability of those services to us. If there are material changes in the availability or cost of transportation services, we may not be able to arrange alternative and timely means to transport our products or fuels at a reasonable cost, which could lead to interruptions or slowdowns in our businesses or increases in our costs.

The availability of railcars can also affect our ability to transport our products. Railcars can be used to transport many different types of products across all of our segments. If owners sell or lease railcars for use in other industries, we may not have enough railcars to transport our products.

We have long-term agreements with shipping companies to provide ships to transport our aggregates products from our Bahamas and Nova Scotia operations to various coastal ports that expire in 2026 and 2027, respectively. Our inability to renew these agreements or enter into new ones with other shipping companies could affect our ability to transport our products.

Some of our products are distributed by barges along rivers in Ohio and West Virginia. We may experience, to a lesser degree, risks associated with distributing our products by barges, including significant delays, disruptions or the non-availability of our barge transportation system that could negatively affect our operations, water levels that could affect our ability to transport our products by barge, and barges that may not be available in quantities that we might need from time to time to support our operations.

Form 10-K ♦ Page 26

Part I ♦ Item 1A – Risk Factors

Our articles of incorporation and bylaws and North Carolina law may inhibit a change in control that you may favor.

Our restated articles of incorporation and restated bylaws and North Carolina law contain provisions that may delay, deter or inhibit a future acquisition of us not approved by our Board of Directors. This could occur even if our shareholders are offered an attractive value for their shares or if many or even a majority of our shareholders believe the takeover is in their best interest. These provisions are intended to encourage any person interested in acquiring us to negotiate with and obtain the approval of our Board of Directors in connection with the transaction. Provisions that could delay, deter or inhibit a future acquisition include the following:

the ability of our Board of Directors to establish the terms of, and issue, preferred stock without shareholder approval;

the requirement that our shareholders may only remove directors for cause;

the inability of our shareholders to call special meetings of shareholders;

super-majority shareholder approval requirements for business combination transactions with certain five percent shareholders; and

advance notice requirements for nominations for election to our board or for proposing matters that can be acted upon by our shareholders at shareholder meetings.

Additionally, the occurrence of certain change-of-control events could result in an event of default under certain of our existing or future debt instruments.