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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

☒ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2025

or

☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number 1-32190

NEWMARKET CORPORATION

Incorporated pursuant to the Laws of the Commonwealth of Virginia

Internal Revenue Service Employer Identification No. 20-0812170

330 South Fourth Street

Richmond, Virginia23219-4350

804-788-5000

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

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

Common Stock, with no par value NEU New York Stock Exchange

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

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

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

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

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

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

Large accelerated filer ☒ Accelerated filer ☐

Non-accelerated filer ☐ Smaller reporting company ☐

Emerging growth company ☐

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

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

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

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

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

The aggregate market value of the registrant's common stock held by non-affiliates of the registrant as of June 30, 2025 (the last business day of the registrant’s most recently completed second fiscal quarter) was approximately $4,530,332,981*

Number of shares of Common Stock outstanding as of January 31, 2026: 9,397,364

DOCUMENTS INCORPORATED BY REFERENCE

Portions of NewMarket Corporation’s definitive Proxy Statement for its 2026 Annual Meeting of Shareholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A under the Securities Exchange Act of 1934 are incorporated by reference into Part III of this Annual Report on Form 10-K.

* In determining this figure, an aggregate of 2,839,094 shares of Common Stock as beneficially owned by Bruce C. Gottwald and members of his immediate family have been excluded and treated as shares held by affiliates. See Item 12. The aggregate market value has been computed on the basis of the closing price on the New York Stock Exchange on June 30, 2025.

Table of Contents

Form 10-K

Table of Contents

PART I

Item 1. Business 3

Item 1A. Risk Factors 12

Item 1B. Unresolved Staff Comments 20

Item 1C. Cybersecurity 20

Item 2. Properties 21

Item 3. Legal Proceedings 22

Item 4. Mine Safety Disclosures 22

PART II

Item 6. Reserved 24

Item 7A. Quantitative and Qualitative Disclosures about Market Risk 36

Item 8. Financial Statements and Supplementary Data 38

Item 9A. Controls and Procedures 82

Item 9B. Other Information 83

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 83

PART III

Item 10. Directors, Executive Officers and Corporate Governance 84

Item 11. Executive Compensation 84

Item 14. Principal Accounting Fees and Services 85

PART IV

Item 15. Exhibits, Financial Statement Schedules 86

Signatures 88

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PART I

ITEM 1. BUSINESS

NewMarket Corporation (NewMarket) (NYSE: NEU) is a holding company and is the parent company of Afton Chemical Corporation (Afton), Ethyl Corporation (Ethyl), American Pacific Corporation (AMPAC), Calca Solutions, LLC (Calca), NewMarket Services Corporation (NewMarket Services), and NewMarket Development Corporation (NewMarket Development). We acquired Calca on October 1, 2025.

Each of our subsidiaries manages its own assets and liabilities. Afton manufactures and sells petroleum additives, while Ethyl markets antiknock compounds in North America and performs contracted manufacturing and related services. AMPAC is a manufacturer of specialty materials primarily used in solid rocket motors for the aerospace and defense industries, and Calca is a producer of hydrazine products used primarily in aerospace and defense applications. NewMarket Development manages the real property that we own in Virginia. NewMarket Services provides various administrative services to NewMarket, Afton, Ethyl, AMPAC, Calca, and NewMarket Development. NewMarket Services expenses are billed to each subsidiary pursuant to services agreements between the companies.

References in this Annual Report on Form 10-K to “we,” “us,” “our,” and “NewMarket” are to NewMarket Corporation and its consolidated subsidiaries, unless the context indicates otherwise.

As a specialty chemicals company, Afton develops and manufactures highly formulated lubricant and fuel additive packages and markets and sells these products worldwide. Afton is one of the largest lubricant and fuel additives companies in the world. Lubricant and fuel additives are necessary products for efficient and reliable operation of vehicles and machinery. From custom-formulated additive packages to market-general additives, we believe Afton provides customers with products and solutions that make engines run smoother, machines last longer, and fuels burn cleaner.

Through an open, flexible, and collaborative style, Afton works closely with its customers to understand their business and help them meet their goals. This style has allowed Afton to develop long-term relationships with its customers in every major region of the world, which Afton serves through its manufacturing facilities across the globe.

Afton has operations in North America, Europe, Asia, Africa, and South America. The economies are generally stable in the countries where we do most of our business, although many of those countries experience economic challenges from time to time. In countries with more political or economic uncertainty, we generally minimize our risk of loss by utilizing U.S. Dollar-denominated transactions, letters of credit, and prepaid transactions.

With almost 450 employees in research, development, and testing, Afton is dedicated to developing additive formulations that are tailored to our customers’ and the end-users’ specific needs. Afton’s portfolio of technologically-advanced, value-added products allows it to provide a full range of products, services, and solutions to its customers.

Ethyl provides contracted manufacturing and related services to Afton and to third parties and is a marketer of antiknock compounds in North America.

AMPAC has operations in the United States and manufactures and sells specialty materials used in solid rocket motors for space launch and military defense applications. AMPAC has long-term relationships with customers and the ability to formulate products to meet the various specification requirements of its customers, resulting in AMPAC being a global leader in specialty materials for use in solid rocket motors.

Calca also has operations in the United States and is the nation's leading producer of Ultra Pure® and high-purity hydrazine. These specialty materials are essential, mission-critical propellants that enable advanced aerospace and defense applications.

NewMarket Development manages the real property we own in Richmond, Virginia consisting of approximately 50 acres. Our corporate offices are included in this acreage, as well as a research and testing facility, and several acres dedicated to other uses. We are exploring various development opportunities for portions of the property as the demand warrants. This effort is ongoing in nature.

We were incorporated in the Commonwealth of Virginia in 2004. Our principal executive offices are located at 330 South Fourth Street, Richmond, Virginia, and our telephone number is (804) 788-5000.

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Business Segments

For the periods presented in this Annual Report on Form 10-K, our business was composed of two segments, petroleum additives, which is primarily represented by Afton, and specialty materials, which is represented by AMPAC and Calca. The antiknock compounds business of Ethyl is reflected in the “All other” category. Each of these is discussed below.

Petroleum Additives -Petroleum additives are used in lubricating oils and fuels to enhance their performance in machinery, vehicles, and other equipment. We manufacture chemical components that are selected to perform one or more specific functions and combine those chemicals with other chemicals or components to form additive packages for use in specified end-user applications. The petroleum additives market is a global marketplace, with customers ranging from large, integrated oil companies to national, regional, and independent companies.

We believe our success in the petroleum additives market is largely due to our ability to deliver value to our customers through our products and our open, flexible, and collaborative working style. We accomplish this by understanding what our customers value and by applying our technical capabilities, formulation expertise, broadly differentiated product solutions, and global supply capabilities to satisfy our customers' needs. We invest significantly in research and development in order to meet our customers’ needs and to adapt to the rapidly changing environment for new and improved products and services.

We view the petroleum additives marketplace as being comprised of two broad product applications: lubricant additives and fuel additives. Lubricant additives are highly formulated chemical solutions that, when blended with base fluids, improve the efficiency, durability, performance, and functionality of mineral oils, synthetic oils, and biodegradable fluids, thereby enhancing the performance of machinery and engines. Fuel additives are chemical components that help oil refiners meet fuel specifications or formulated packages that improve the performance of gasoline, diesel, biofuels, and other fuels, resulting in lower operating costs, improved vehicle performance, and reduced emissions.

Lubricant Additives

Lubricant additives are essential ingredients for making lubricating oils. Lubricant additives are used in a wide variety of vehicle and industrial applications, including engine oils, transmission fluids, off-road powertrain and hydraulic systems, gear oils, hydraulic oils, turbine oils, and virtually any other application where metal-to-metal moving parts are utilized. Lubricant additives are organic and synthetic chemical components that enhance wear protection, prevent deposits, and protect against the hostile operating environment of an engine, transmission, axle, hydraulic pump, or industrial machine.

Lubricants are widely used in operating machinery from transportation vehicles to heavy industrial equipment to provide a layer of protection between moving mechanical parts. Without this layer of protection, the normal functioning of machinery would not occur. Effective lubricants reduce downtime and increase efficiency. Specifically, lubricants serve the following main functions:

•friction reduction—Friction is reduced by maintaining a thin film of lubricant between moving surfaces, preventing them from coming into direct contact with one another and reducing wear on moving machinery, thereby providing longer life and operational efficiency.

•heat removal—Lubricants act as coolants by removing heat resulting either from friction or through contact with other, higher temperature materials.

•containment of contaminants—Lubricants function by carrying contaminants away from the machinery and neutralizing the harmful impact of the by-products created by combustion.

The functionality of lubricants is created through an exact balance between a base fluid and performance-enhancing additives. This balance is the goal of effective formulations achieved by experienced research and development professionals. We offer a full line of lubricant additive packages, each of which is composed of component chemicals specially selected to perform desired functions. We manufacture most of the chemical components and blend these components to create formulated additive packages designed to meet industry and customer specifications. Lubricant additive components are generally classified based upon their intended functionality, including:

•detergents, which clean moving parts of engines and machines, suspend oil contaminants and combustion by-products, and absorb acidic combustion products;

•dispersants, which serve to inhibit the formation of sludge and particulates;

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•extreme pressure/antiwear agents, which reduce wear on moving engine and machinery parts;

•viscosity index modifiers, which improve the viscosity and temperature characteristics of lubricants and help the lubricant flow evenly to all parts of an engine or machine; and

•antioxidants, which prevent oil from degrading over time.

We are one of the leading global suppliers of specially formulated lubricant additives that combine some or all of the components described above to develop our products. Our products are highly formulated, complex chemical compositions derived from extensive research and testing to ensure all additive components work together to provide the intended results. Our products are engineered to meet specifications prescribed by either the industry or a specific customer. Purchasers of lubricant additives tend to be integrated oil companies or independent compounders/blenders. We make no sales directly to end-users or to original equipment manufacturers (OEMs).

We view our participation in the lubricant marketplace in three primary areas: engine oil additives, driveline additives, and industrial additives. Our view is not necessarily the same way others view the market.

Engine Oil Additives - The largest submarket within the lubricant additives marketplace is engine oil additives which consists of additives designed for passenger cars, motorcycles, on and off-road heavy duty commercial equipment, locomotives, and large engines in ocean-going vessels. We estimate engine oil additives represent approximately 70% of the overall lubricant additives market volume.

The engine oil market’s primary customers include consumers, fleet owners, mining and construction companies, farmers, railroads, shipping companies, service dealers, and OEMs. The primary functions of engine oil additives are to reduce friction, prevent wear, control formation of sludge and oxidation, and prevent rust. Engine oil additives are typically sold to lubricant manufacturers who combine them with a base oil fluid to meet internal, industry, and OEM specifications.

Key drivers of engine oil additives demand are the number of vehicles on the road, total vehicle miles driven, fuel economy, the average age of vehicles on the road, drain intervals, engine and crankcase size, changes in engine design, and temperature and specification changes driven by OEMs. The extension of drain intervals has generally offset increased demand due to higher vehicle population, new hardware, and more miles driven. Other key drivers include industrial production rates, agricultural output, mining and construction output, environmental regulations, and infrastructure investments of commercial companies. Afton offers products that enhance the performance of mineral, part-synthetic, and fully-synthetic engine oils.

Driveline Additives - The driveline additives submarket is comprised of additives designed for products such as transmission fluids, axle fluids, and off-road powertrain fluids. This submarket shares in the 30% of the market which is not covered by engine oil additives. Transmission fluids primarily serve as the power transmission and heat transfer medium in the area of the transmission where the torque of the drive shaft is transferred to the gears of the vehicle. Axle fluids lubricate gears and bearings in axles, and powertrain fluids are used in off-highway powertrain and hydraulic systems. Other products in this area include power steering fluids, shock absorber fluids, gear oils, and lubricants for heavy machinery. Additionally, as a leading additive supplier to the electric vehicle market, we are investing in and delivering new technologies to enable electric vehicle market growth to help reduce carbon emissions. We anticipated and are responding to the need for future lubricants to consider conductivity, the effect of electric fields, low friction/high speed, noise, and battery cooling or copper wire drawing. All driveline additives products must conform to highly prescribed specifications developed by vehicle OEMs for specific models or designs. Driveline additives are generally sold to oil companies for ultimate sale to vehicle OEMs for new vehicles (factory-fill), service dealers for aftermarket servicing (service-fill), retailers, and distributors.

Key drivers of the driveline additives marketplace are the number of vehicles manufactured, total number of vehicles in operation, drain intervals for transmission fluids and axle fluids, changes in engine and transmission design and temperatures, and specification changes driven by OEMs.

Industrial Additives - The industrial additives submarket is comprised of additives designed for products for industrial applications such as hydraulic fluids, grease, industrial gear fluids, and industrial specialty applications, such as turbine oils. This submarket also shares in the 30% of the market not covered by engine oil additives. These products must

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conform to industry specifications, OEM requirements, and/or application and operating environment demands. Industrial additives are generally sold to oil companies, service dealers for aftermarket servicing, and distributors.

Key drivers of the industrial additives marketplace are gross domestic product levels and industrial production.

Fuel Additives

Fuel additives are chemical compounds that are used to improve both the oil refining process and the performance of gasoline, diesel, biofuels, and other fuels. Benefits of fuel additives in the oil refining process include reduced use of crude oil, lower processing costs, and improved fuel storage properties. Fuel performance additives enhance fuel economy, improve ignition and combustion efficiency, reduce emission particulates, maintain engine cleanliness, and protect against deposits in fuel injectors, intake valves, and the combustion chamber. Our fuel additives are extensively tested and designed to meet stringent industry, government, OEM, and individual customer requirements.

Many different types of additives are used in fuels. Their use is generally determined by customer, industry, OEM, and government specifications, and often differs from country to country. The types of fuel additives we offer include:

•gasoline performance additives, which clean and maintain key elements of the fuel delivery systems, including fuel injectors and intake valves, in gasoline engines;

•diesel fuel performance additives, which perform similar cleaning functions in diesel engines;

•cetane improvers, which increase the cetane number (ignition quality) in diesel fuel by reducing the delay between injection and ignition;

•stabilizers, which reduce or eliminate oxidation in fuel;

•corrosion inhibitors, which minimize the corrosive effects of combustion by-products and prevent rust;

•lubricity additives, which restore lubricating properties lost in the refining process;

•cold flow improvers, which improve the pumping and flow of distillate and diesel fuels in cold temperatures; and

•static dissipating additives.

We offer a broad line of fuel additives worldwide and sell our products to major fuel marketers and refiners, as well as independent terminals and other fuel blenders.

Key drivers in the fuel additive marketplace include total vehicle miles driven, fuel economy, the introduction of new engine designs, regulations on emissions (both gasoline and diesel), quality of the crude oil slate and performance standards, and marketing programs of major oil companies.

Competition

We believe we are one of the four largest manufacturers and suppliers in the petroleum additives marketplace.

In the lubricant additives submarket, our major competitors are The Lubrizol Corporation (a wholly-owned subsidiary of Berkshire Hathaway Inc.), Infineum (a joint venture between ExxonMobil Chemical and Shell plc), and Chevron Oronite Company LLC. There are several other suppliers in the worldwide market who are competitors in their particular product areas.

The fuel additives submarket is characterized by more competitors. While we participate in many facets of the fuel additives market, our competitors tend to be more narrowly focused. In the gasoline detergent market, we compete mainly against BASF, Chevron Oronite Company LLC, Innospec Inc., and The Lubrizol Corporation. In the diesel and refinery markets, we compete mainly against The Lubrizol Corporation, Infineum, BASF, Clariant Ltd., Dorf Ketal, and Innospec Inc. We also compete against other regional companies in the fuel additives marketplace.

The competition among the participants in these industries is characterized by the need to provide customers with cost-effective, technologically-capable products that meet or exceed industry specifications. The need to continually increase technology performance and lower cost through formulation technology and cost improvement programs is vital for success in this environment.

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Specialty Materials - Our specialty materials segment is principally engaged in the production of both perchlorates, which include several grades of ammonium perchlorate, sodium perchlorate, and potassium perchlorate, and hydrazine, including Ultra Pure® and high-purity hydrazine.

Perchlorates - Ammonium perchlorate is a key component of solid rocket motors, booster motors, and missiles that are utilized in U.S. Department of War tactical and strategic missile programs. Ammonium perchlorate is also used in space exploration programs for the National Aeronautics and Space Administration (NASA) and commercial space launch vehicles.

We supply ammonium perchlorate for use in a number of defense and space launch programs of the U.S. and U.S. allies via U.S. government agencies, government contractors, and foreign contractors. Exporting ammonium perchlorate is subject to federal regulation that permits our foreign sales of ammonium perchlorate. We obtain export licenses on a case-by-case basis, which are dependent upon the ultimate use of our product.

Customers of ammonium perchlorate primarily consist of rocket motor manufacturers supplying the U.S. Department of War and NASA programs, as well as entities providing commercial space launch applications and foreign military applications.

Demand for ammonium perchlorate is program-specific and dependent upon, among other things, governmental appropriations. The need for tactical rockets, strategic missiles, and solid rocket boosters is anticipated to provide the base demand over the coming five-year period and beyond.

We also produce and sell different types and grades of sodium and potassium perchlorates, which have a wide variety of applications, including munitions, explosives, propellants, perchloric acid, initiators, electronics, batteries, plastics, electro-machining, and porcelain.

Hydrazine - Hydrazine is a highly reactive chemical used primarily in aerospace, defense, and space propulsion applications. We produce multiple grades of hydrazine, including Ultra Pure® and high-purity hydrazine, which are manufactured to meet stringent customer and program-specific specifications.

Hydrazine is a critical component in satellite propulsion systems, where it is used as a monopropellant for orbit insertion, station-keeping, attitude control, and deorbiting functions. These applications are integral to both government and commercial satellite programs, including national security, civil space, and communications constellations. Due to the demanding performance and reliability requirements of these missions, hydrazine products must meet exacting purity, stability, and contamination control standards.

We supply hydrazine products directly and through qualified distributors to U.S. government agencies, government contractors, and commercial aerospace customers, as well as to certain international customers subject to applicable export controls. The manufacture, handling, storage, transportation, and export of hydrazine are subject to extensive regulations, including environmental, safety, and export control requirements. Export sales are conducted in compliance with U.S. regulations and may require licensing depending on end use and destination.

Demand for hydrazine is driven by satellite production rates, launch activity, and on-orbit replacement cycles, as well as by governmental budgets and commercial space investment trends. We believe that long-term growth in satellite deployment, including defense, civil, and commercial space applications, will continue to support demand for high-purity hydrazine products.

Competition - We believe we are a leading manufacturer and seller of ammonium perchlorate globally. We are aware of other production capacity in the United States for perchlorate chemicals, including ammonium perchlorate, as well as production capacity in France, Japan, Brazil, China, India, and Taiwan. While we have limited information with respect to these facilities, we believe that these producers are not qualified as ammonium perchlorate suppliers for most U.S. Department of War and NASA programs, which represent the majority of domestic ammonium perchlorate demand.

Competition among producers of ammonium perchlorate is characterized by the ability to meet customer specifications including unique particle size requirements, reasonable lead times, and qualification of a given production process. The need to maintain a qualified production process and meet changing demand requirements is vital for success in this environment.

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We believe that we are the leading producer of Ultra Pure® and high-purity hydrazine in the U.S. We are aware of other hydrazine producers globally; however, not all producers are qualified to supply Ultra Pure® or high-purity hydrazine for aerospace, space propulsion, and defense applications. Qualification of a hydrazine supplier and production process can require extended testing, customer audits, and program approvals.

Competition in the hydrazine market is characterized by limited qualified producers, high regulatory barriers to entry, and strict customer qualification requirements. Customers evaluate suppliers based on product purity, consistency, safety performance, regulatory compliance, reliability of supply, and experience supporting mission-critical aerospace and defense programs.

All Other -The “All other” category includes the operations of the antiknock compounds business (primarily sales of antiknock compounds in North America), as well as certain contracted manufacturing and related services performed by Ethyl. Our Ethyl facility is located in Houston, Texas and is substantially dedicated to terminal operations related to antiknock compounds and other fuel additives. The financial results of the petroleum additives activities performed by Ethyl are reflected in the petroleum additives segment results. The “All other” category financial results include a service fee charged by Ethyl for its production services to Afton.

Raw Materials and Product Supply

Petroleum Additives - We use a variety of raw materials and chemicals in our manufacturing and blending processes and believe the sources of these are adequate for our current operations. The primary raw materials for Afton are base oil, polyisobutylene, antioxidants, alcohols, solvents, detergents, friction modifiers, olefins, and copolymers.

As the performance requirements of our products become more complex, we often work with highly specialized suppliers. In some cases, we source from a single supplier. In such cases, we manage our risk by maintaining safety stock of the raw material or qualifying alternate suppliers, which could take additional time to implement, but we are confident we can ensure continued supply for our customers.

While we have experienced improvement in the supply chain disruptions which impacted the petrochemicals industry over the past several years, we continuously monitor our raw material supply levels and adjust our procurement strategies as conditions require.

Specialty Materials - The primary raw materials are electricity, sodium chlorate, ammonia, chlorine, caustic, and hydrochloric acid. Graphite is utilized in the fabrication of the electrolytic cells used in the manufacturing process of perchlorates and is replaced on a periodic basis. All of the raw materials used in the manufacturing process are available in commercial quantities from multiple sources.

Research, Development, and Testing

Research, development, and testing (R&D) provides Afton with new performance-based solutions for our customers in the petroleum additives market. We develop products through a combination of chemical synthesis, formulation development, engineering design, and performance testing. In addition to developing new products, R&D provides our customers and OEMs with data to substantiate product differentiation and technical support to assure total customer satisfaction.

We are committed to providing the most advanced products, comprehensive testing programs, and superior technical solutions tailored to the needs of our customers and OEMs worldwide. Afton continues to successfully implement techniques to drive efficiency in technology discovery and development, while aligning our internal testing to market changes, research, customer support, and predictive capabilities around the world in support of our goals of providing market-driven technical leadership and performance-based differentiation. In 2025, we continued to invest in and progress our technology plans and have a team focused on adjacent spaces that can utilize our chemistry and technology.

Afton continues to develop new products and technology to keep our customers well-positioned for the future by meeting evolving OEM requirements, including specific demands of hybrid and electric vehicles, industry specifications, and environmental regulations. A significant portion of our R&D investment is dedicated to the development of products that are differentiated by their ability to deliver improved fuel efficiency and durability in addition to robust performance in a wide range of new vehicle and industrial equipment designs. Afton’s state-of-the art testing capabilities enable

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customized research in all areas of performance needed by both OEMs and tier one suppliers, including the latest advancements in e-mobility. Our leading-edge capabilities and fundamental understanding in the areas of combustion, friction control, energy efficiency, electric motor compatibility, and wear prevention are used to set the stage for next-generation products in all areas.

In line with Afton’s vision, we continue to focus our technology to make the world a better place by reducing the use of chemicals of concern, using more raw materials from sustainable sources, developing additives that enable some of the world’s most energy efficient fluids, creating fuel additives that enable engines to be more efficient, and being a market leader in transmission fluids for full battery electric vehicles. We continue to operate our laboratories safely with a focus on Vision of Zero - our vision of no injuries, accidents, incidents, or harm to the environment.

In 2025, we successfully launched new technologies across all our lubricant additives and fuel additives product areas. We developed new engine oil products for passenger cars and commercial trucks in support of our customers in all the major regions of the world in which we operate, including engine oil technology designed for the latest passenger cars and heavy duty engine oil (HDEO) specification, best in class electric vehicle transmission fluid, more robust fuel additives, as well as technology-leading industrial fluids.

We continued to develop new products in multiple application areas in the industrial additives sector, including hydraulic, industrial gear, turbine, slideway, and grease additives. Research is focused on the development of technologies that will provide differentiation to our customers in multiple performance areas, including equipment life, reliability, and energy efficiency, as well as eliminating or reducing chemicals of concern. This includes launching our next generation hydraulic and gear technology which maintains our technology leadership in this important market.

In the driveline additive submarket, research continued in our transmission fluid, axle oil, and tractor fluid product lines. This included the development of new OEM-specific additives used in factory-fill fluids installed during automotive component and vehicle assembly. We continue to launch new OEM-specific technology for full battery electric passenger and commercial vehicles and are a top supplier in this growing market. We developed new products for the service-fill sector to provide our customers with the latest additive technology available and continue to advance our market-leading and technology-leading battery electric vehicle transmission fluid which pushes the forefront of compatibility, gear protection, and efficiency.

We also provide leading technology in the fuel additives area. In 2025, we continued to implement our latest gasoline and diesel technology. Our next generation diesel technology is more efficient and is designed not only for conventional, but also renewable diesel. In addition, we continue to maintain close interactions with regulatory, industry, and OEM leaders to guide our development of future fuel additives technologies based on well-defined market needs.

Afton remains committed to providing the most advanced products, comprehensive testing programs, and superior technical solutions tailored to the needs of our customers and OEMs worldwide.

Intellectual Property

Our intellectual property, including our patents, licenses, and trademarks, is an important component of our business. We actively protect our inventions, new technologies, and product developments by filing patent applications and maintaining trade secrets. We currently own approximately 1,400 issued or pending United States and foreign patents. In addition, we have acquired the rights under patents and inventions of others through licenses or otherwise. We take care to respect the intellectual property rights of others, and we believe our products do not infringe upon those rights. We vigorously participate in patent opposition proceedings around the world, where necessary, to secure a technology base free of infringement. We believe our patent position is strong, aggressively managed, and sufficient for the conduct of our business.

We also have several hundred trademark registrations throughout the world for our marks, including NewMarket®, Afton Chemical®, Ethyl®, AMPAC®, HiTEC®, Passion for Solutions®, Halotron®, ZeenClean®, Scav-Ox®, Ultra Pure®, DriveMore®, andAxcel®.

Human Capital

Our Values are the foundation of our company and support the inclusive and respectful culture we have established in all of our locations around the world. Our Values include:

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•unquestionable integrity,

•respect for people,

•safety and environmental responsibility,

•partnership with customers and suppliers,

•continuously improving quality,

•good citizenship, and

•economic viability.

We place the highest level of commitment on safety and strive to operate our business every day focused on its importance. Keeping our employees safe is a management priority.

We have a diverse workforce, representative of the geographic regions in which we do business. We place a high value on diverse thoughts, skills, perspectives, cultures, and knowledge because we believe that such diversity results in better business decision making. We employed approximately 2,050 people at the end of 2025. Approximately 1,150 were located in the United States, 400 were in the Europe/Middle East/Africa/India region, 300 were in the Asia Pacific region, and 200 were in the Latin America region. Approximately 20% of our workforce is represented by unions.

When we hire new employees, our goal is that they stay with us for the remainder of their career. Hiring the right people for the long-term and developing them for key roles is a critical focus area. To be successful, we must attract and retain a highly qualified and technically competent workforce, including key employees in R&D and leadership positions. In addition to utilizing our internal network, contacts, and specialized recruiters to identify and attract qualified personnel, we have established relationships with a number of universities globally and have intern and co-op programs in many of our locations.

Globally, approximately 18% of our employees have 20 years or more of service, and over the three-year period from 2023 through 2025, our resignation rate was approximately 4.1%. We believe these measures demonstrate our success in hiring the right employees for the long-term and establishing a culture where respect for people is an everyday value.

Commitment to Environmental and Safety Excellence

Our commitment to the environment and safety excellence applies to every employee, contractor, and visitor every day, at every site. Safety and environmental responsibility are a way of life at NewMarket - enhancing operations, the way we work, and the relationships we maintain with our employees, customers, supply chain partners, and the communities in which we operate. Our objective is to establish a culture where our employees understand that good environmental and safety performance is good business and understand that environmental compliance and safety are individual responsibilities. Every employee at NewMarket is responsible for ensuring that our high standards in the area of health, safety (including process safety), environmental protection, and security are upheld at all times.

Our Global Responsible Care Policy Statement includes a commitment to conduct operations in a manner that protects our employees, communities, and the environment, to comply with all applicable laws and regulations, and to reduce our environmental impact. Additionally, in pursuit of our Vision of Zero, we work with our employees and other key stakeholders to establish appropriate goals, objectives, and targets.

Within NewMarket, our businesses are committed to globally implementing Responsible Care® (a registered service mark of the American Chemistry Council (ACC)) via formal EHS (environmental health and safety) Management Systems. Our Responsible Care® management systems are certified by independent third-party auditing processes. North American facilities within Ethyl and Afton have certified to RCMS and RC14001®, respectively. Additionally, Afton’s Feluy, Belgium; Suzhou, China; Tsukuba, Japan; Rio de Janeiro, Brazil; Bracknell, England; and Singapore facilities are all certified to the environmental standard ISO 14001. The Singapore site is also certified to ISO 45001, a global occupational health and safety standard, and in 2025 became our first location to add ISO 50001 Energy Management certification. Our San Juan del Rio, Mexico site is formally certified to both RC 14001/ISO 14001. Afton’s Sauget, Illinois plant continues to proudly be an OSHA VPP (Voluntary Protection Program) “Star” worksite. The AMPAC site in Cedar City, Utah joined the ACC in 2024 and is pursuing RCMS certification. The newly acquired Calca

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site in Lake Charles, Louisiana has been a leader in the Society of Chemical Manufacturers and Affiliates (SOCMA), implementing their ChemStewards® program, and will also pursue RCMS certification in the future.

In 2025, we continued to enhance our “Actively Caring” safety program, where people look out for the safety and welfare of others with courage and compassion, enabling the achievement of an injury-free environment. The NewMarket worldwide injury/illness recordable rate (which is the number of injuries per 200,000 hours worked) was 1.10 in 2025. We had zero serious injuries in 2025 and achieved zero recordable injuries at many Afton facilities including our Singapore, Ashland Technical Center, Port Arthur, Suzhou, and Tsukuba facilities. Zero recordable injuries was also achieved for Calca, since its acquisition on October 1, 2025, and Ethyl. We continue to focus on our Vision of Zero improvement plans and actions across our sites to advance our safety-first culture. We launched a new investigation process for significant incidents that is delivering more thorough incident learning and better targeted corrective actions – while looking more deeply at root cause and contributing factors. This is helping our leaders demonstrate ownership and accountability to help reduce risk and drive improved performance. We share learnings across sites globally and remain more committed than ever to achieving our aspiration of zero injuries and incidents.

As members of the ACC, we provide data on metrics used to track environmental impact, safety, energy use, community outreach and emergency preparedness, greenhouse gas intensity, security and product stewardship performance along with other ACC member companies. These can be viewed on the American Chemistry Council website. The information on this website is not, and shall not be deemed to be, a part of this Annual Report on Form 10-K or incorporated by reference in this Annual Report on Form 10-K or any other filings we make with the Securities and Exchange Commission (SEC).

Governmental and Environmental Regulations

As a chemical company, we are subject to regulation by local, state, federal, and foreign governmental authorities specific to the production, distribution, management, and stewardship of chemicals. Certain portions of our specialty materials segment are subject to the International Traffic in Arms Regulations, a set of U.S. government regulations that controls the export of defense and military technologies, and its international sales require export licenses on a case-by-case basis.

In addition, in the United States and under similar foreign and state laws, we are subject to a variety of environmental laws and regulations, as well as environmental liabilities associated with the investigation and cleanup of hazardous substances. These liabilities may include personal injury, property damage, or natural resource damages arising from the release of, or exposure to, hazardous substances. They may be imposed on us in a range of situations without regard to violation of law or regulations. They may also be imposed jointly and severally, where one party may be held liable for a disproportionate share of the damages, up to and including the entire loss. These liabilities may include entities with any possible connection to the hazardous substances, including, for example, entities that formerly owned or operated a property or entities that arranged for disposal of hazardous substances from a property.

We believe we comply, in all material respects, with laws, regulations, statutes, and ordinances, including, but not limited to, those protecting the environment, as well as those related to the management and stewardship of chemicals. We have policies and procedures in place that establish regular reviews of our regulatory and environmental compliance and product stewardship and actively monitor any significant existing or potential regulatory changes or environmental issues that could materially affect us.

Our total accruals for environmental remediation, dismantling, and decontamination were approximately $14 million at December 31, 2025 and $11 million at December 31, 2024. As new technology becomes available, it may be possible to reduce accrued amounts. While we believe that we are currently fully accrued for known environmental issues, it is possible that unexpected future costs could have a significant financial impact on our financial position, results of operations, and cash flows.

The costs of complying with existing environmental, health, and safety laws and regulations as they pertain to our products and operations, including remediation, closure, and post-closure costs, are primarily included in cost of goods sold. We spent approximately $44 million in 2025, $37 million in 2024, and $41 million in 2023 for ongoing environmental operating and clean-up costs, excluding depreciation of previously capitalized expenditures.

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In addition to the ongoing environmental compliance costs and the costs to remediate contaminated sites, worldwide capital expenditures for pollution prevention and safety projects were $12 million in 2025, $13 million in 2024, and $10 million in 2023.

The costs of complying with governmental pollution prevention and safety regulations are subject to:

•potential changes in applicable statutes and regulations (or their enforcement and interpretation);

•uncertainty as to the success of anticipated solutions to pollution problems;

•uncertainty as to whether additional expense may prove necessary; and

•potential for emerging technology to affect remediation methods and reduce associated costs.

Availability of Reports Filed with the Securities and Exchange Commission and Corporate Governance Documents

Our website address is www.newmarket.com. We make available, free of charge through our website, our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (Exchange Act), as soon as reasonably practicable after such documents are electronically filed with, or furnished to, the SEC. The information on our website is not, and shall not be deemed to be, a part of this Annual Report on Form 10-K or incorporated by reference in this Annual Report on Form 10-K or any other filings we make with the SEC. We file our annual, quarterly and current reports, proxy statements, and other information with the SEC. Our SEC filings are available to the public on the SEC's website at www.sec.gov.

Information about our Executive Officers

The names and ages of all executive officers as of February 12, 2026 follow.

Name Age Positions

Bryce D. Jewett, III 51 Executive Vice President and General Counsel

Brian D. Paliotti 49 President, Afton Chemical Corporation

Our officers, at the discretion of the Board of Directors, hold office until the meeting of the Board of Directors following the next annual shareholders’ meeting. Mr. Gottwald, Mr. Hazelgrove, and Mr. Jewett have served in their capacity for at least the last five years. Mr. Fitzgerald and Mr. Paliotti have served in their capacities for less than five years.

Mr. Fitzgerald joined the company in November 2014 as Operations Finance Director, became Treasurer and Finance Director on January 1, 2024, and was appointed Vice President and Chief Financial Officer on January 1, 2025. Mr. Paliotti joined NewMarket in June 2008 as Financial Officer for Afton Chemical Corporation, was appointed Senior Financial Officer of NewMarket Services Corporation in October 2011, promoted to Vice President, Finance of NewMarket Services Corporation in May 2013, and promoted to Vice President and Chief Financial Officer in January 2015. He became President of Afton Chemical Corporation on January 1, 2023.

ITEM 1A. RISK FACTORS

Our business is subject to many factors that could have a material adverse effect on our future performance, results of operations, financial condition, or cash flows and could cause our actual results to differ materially from those expressed

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or implied by forward-looking statements made in this Annual Report on Form 10-K. Those risk factors are outlined below.

Market and Supply Chain Risks

•Sudden, sharp, or prolonged changes in the prices of and/or demand for raw materials may adversely affect our profit margins.

We utilize a variety of raw materials in the manufacture of our products, including base oil, polyisobutylene, antioxidants, alcohols, solvents, detergents, friction modifiers, olefins, and copolymers. We may also enter into contracts which commit us to purchase some of our more critical raw materials based on anticipated demand. Our profitability is sensitive to changes in the quantities of raw materials we may need and the costs of those materials which may be caused by changes in supply, demand or other market conditions, including general inflation, over which we have little or no control. Political and economic conditions globally have caused, and may continue to cause, our demand for and the cost of our raw materials to fluctuate. War, armed hostilities, terrorist acts, civil unrest, inclement weather events, tariffs, or other incidents may also cause a sudden, sharp, or prolonged change in our demand for and the cost of our raw materials. We cannot assure that we will be able to pass on to our customers any future increases in raw material costs in the form of price increases for our products. If our demand for raw materials were to decline such that we would not have need for the quantities required to be purchased under commitment agreements, we could incur additional charges that would affect our profitability.

•Lack of availability of raw materials, including sourcing from some single suppliers, could negatively impact our ability to meet customer demand.

The chemical industry can experience limited supply of certain materials. In addition, in some cases, we choose to source from a single supplier. Any significant disruption in supply, for any reason, could adversely affect our ability to obtain raw materials, which in turn could adversely affect our ability to ensure continued supply for our customers and to meet customer demand.

•Competitive pressures could adversely affect our margins and profitability.

We face significant competition in all of the product lines and markets in which we operate. We expect that our competitors will develop and introduce new and enhanced products, which could cause a decline in the market acceptance of certain products we manufacture. In addition, as a result of price competition, we may be compelled to reduce the prices for some of our products, which could adversely affect our margins and profitability. Some of our competitors may also have greater financial, technological, and other resources than we have and may be able to maintain greater operating and financial flexibility than we are able to maintain. As a result, these competitors may be able to better withstand changes in conditions within our industry, changes in the prices for raw materials, and changes in general economic conditions.

•We rely on a small number of significant customers concentrated in the lubricant and fuel industries. The loss of sales to any of these customers could significantly reduce our revenues and negatively affect our profitability.

Our principal customers are multinational oil companies in the lubricant and fuel industries. These industries are characterized by the concentration of a few large participants. This concentration of customers affects our overall risk profile, since our customers will be similarly affected by changes in economic, geopolitical, and industry conditions. Many factors affect the level of our customers’ spending on our products, including, among others, general business conditions, changes in technology, interest rates, oil prices, and consumer confidence in future economic conditions. A sudden or protracted downturn in these industries could adversely affect the buying power of, and purchases by, our customers. The loss of a significant customer or a material reduction in purchases by a significant customer could reduce our revenues and negatively affect our profitability.

•A significant portion of our specialty materials business is under contracts with contractors or subcontractors of the U.S. government or directly with the U.S. government. These contracts are impacted by governmental priorities, as well as shutdowns, and are subject to potential fluctuations in

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funding or early termination, including for convenience, any of which could have a material adverse effect on our results of operations, financial condition, or cash flows.

Sales to U.S. government contractors and subcontractors, as well as directly to the U.S. government, represent a significant portion of our specialty materials business. Funding of U.S. governmental programs is generally subject to annual congressional appropriations, which are subject to change. In the case of major programs, U.S. government contracts are usually incrementally funded. In addition, U.S. government expenditures for defense and space programs may fluctuate from year to year, and specific programs may be terminated or curtailed. The U.S. government often has the ability to terminate contracts, in whole or in part, for convenience. If this were to occur, the full profit anticipated under a given contract is unlikely to be realized. A shift in governmental priorities, programs, strategies, or funding levels impacting the defense and space industries more generally or the specific areas of those industries in which we operate could negatively affect our results of operations, financial condition, or cash flows.

Operational Risks

•A disruption in the availability or capacity of distribution systems could negatively impact our ability to meet our customers’ needs and affect our competitive position.

We rely on a variety of modes of transportation to deliver products to our customers, including rail cars, cargo ships, and trucks. We depend upon the availability of a distribution infrastructure to deliver our products in a safe and timely manner. Any disruptions in this infrastructure network, whether caused by human error, accidents, armed conflicts, deliberate acts of violence, limitations on capacity, repairs and improvements to infrastructure components, earthquakes, storms, or other natural disasters, could adversely affect our ability to meet customer demand.

•A significant disruption or disaster at one of our production facilities, including those facilities which are sole producers of certain of our products, could result in our inability to meet production requirements and projected customer demand resulting in a negative impact to our profitability and relationships with our customers. These could also potentially result in us incurring significant liabilities.

We are dependent upon the continued safe operation of our production facilities. Several of the products we sell are produced only in one location. A prolonged disruption or disaster at one of our facilities could result in our inability to meet production requirements.

Our production facilities are subject to various hazards associated with the manufacturing, handling, storage, and transportation of chemical materials and products, including some that are reactive, explosive, and flammable. Such hazards could include leaks, ruptures, chemical spills, explosions, or fires which result in the discharge or release of toxic or hazardous substances or gases; mechanical failures; unscheduled downtime; and environmental hazards. The occurrence of any of these hazards could cause a disruption in the production of our products and may diminish our ability to meet output goals. These sites may also experience significant disruptions in operations due to inclement weather, natural disasters, flooding, and levee breaches. We cannot assure that our facilities will not experience these types of hazards and disruptions in the future or that these incidents will not result in production delays and affect our ability to meet production requirements. Any such hazards or disruptions at our facilities could result in us losing revenue or not being able to maintain our relationships with our customers.

Additionally, some of the hazards or disruptions mentioned above could result in significant liabilities related to personal injury and loss of life; severe damage to, or destruction of, property and equipment; and environmental contamination.

•Our research and development efforts are costly and may not succeed, which could impair our ability to meet our customers’ needs, affect our competitive position, and result in a loss of market share.

The petroleum additives industry is subject to periodic technological change, changes in performance standards, and ongoing product improvements. Further, technological changes in some or all of our customers’ products or processes, including the development and customer acceptance of electric vehicles, may make some of our products obsolete. As a result, the life cycle of our products is often hard to predict. In order to maintain our

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profits and remain competitive, we must effectively respond to technological changes in our industry and successfully develop, manufacture, and market new or improved products in a cost-effective and timely manner. As a result, we must commit substantial resources each year to research and development to maintain and enhance our technological capabilities and meet our customers’ changing needs. Ongoing investments in research and development for future products could result in higher costs without a proportional increase in profits. Additionally, for any new product program, there is a risk of technical or market failure in which case we may not be able to develop the new commercial products needed to maintain and enhance our competitive position, or we may need to commit additional resources to new product development programs. Moreover, new products may have lower margins than the products they replace.

•In order to be successful, we must attract and retain a highly qualified workforce, including key employees in R&D and leadership positions.

The success of our business is highly dependent on our ability to attract and retain highly qualified personnel to support our research and development efforts and our agility in effectively responding to technological changes in our business. To the extent that the demand for skilled personnel exceeds supply, we could experience higher labor, recruiting, or training costs in order to attract and retain such a work force. We compete with other companies for qualified technical and scientific personnel such as chemical, mechanical, and industrial engineers. To the extent that we lose experienced personnel through wage competition, normal attrition (including retirement), or other means, we must be able to attract qualified candidates to fill those positions and successfully manage the transfer of critical knowledge from those individuals leaving our company. An inability to maintain a highly qualified technical workforce could adversely affect our competitive position and result in a loss of market share.

We also must manage leadership development and succession planning throughout our business. To the extent that we are unable to attract, develop, and retain leadership talent successfully, we could experience business disruptions that adversely affect our ability to grow our business.

•Failure to protect our intellectual property rights could harm our competitive position and could adversely affect our future performance and growth.

Protection of our proprietary processes, methods, compounds, and other technologies is important to our business. We depend upon our ability to develop and protect our intellectual property rights to distinguish our products from those of our competitors. Failure to protect our existing intellectual property rights may result in the loss of valuable technologies or having to pay other companies for infringing on their intellectual property rights. An inability to continue using certain of our trademarks or service marks could result in the loss of brand recognition and could require us to devote additional resources to advertise, rebrand our products, and market our brands. See Item 1, “Business-Intellectual Property.”

We rely on a combination of patent, trade secret, trademark, and copyright laws, as well as judicial enforcement, to protect our intellectual property and technologies. We cannot assure that the measures taken by us to protect these assets and rights will provide meaningful protection or that adequate remedies will be available in the event of an unauthorized use or disclosure of our trade secrets or manufacturing expertise. We cannot assure that any of our intellectual property rights will not be challenged, invalidated, circumvented, or rendered unenforceable. In addition, we have manufacturing operations in countries where we may not have the same strength of intellectual property protection and enforcement as in North America or Europe, resulting in a greater risk of a third party appropriating our intellectual property.

Furthermore, we cannot assure that any pending patent application filed by us will result in an issued patent, or if patents are issued to us, that those patents will provide meaningful protection against competitors or against competitive technologies. We could face patent infringement claims from our competitors or others alleging that our processes or products infringe on their proprietary technologies. If we were found to be infringing on the proprietary technology of others, we may be liable for damages, and we may be required to change our processes, redesign our products partially or completely, pay to use the technology of others, or stop using certain technologies or producing the infringing product entirely. Even if we ultimately prevail in an infringement suit, the existence of the suit could prompt customers to switch to products that are not the subject

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of infringement suits. We may not prevail in any intellectual property litigation, and such litigation may result in significant legal costs or otherwise impede our ability to produce and distribute key products.

We also rely on unpatented proprietary manufacturing expertise, continuing technological innovation, trade secrets, and other intellectual property to develop and maintain our competitive position. While we generally enter into confidentiality agreements with our employees and third parties to protect our intellectual property, we cannot assure that our confidentiality agreements will not be breached, that they will provide meaningful protection for our trade secrets and proprietary manufacturing expertise, or that adequate remedies will be available in the event of an unauthorized use or disclosure of our trade secrets or manufacturing expertise.

In addition, our trade secrets and know-how may be improperly obtained by other means, such as a breach of our information technology security systems or direct theft. Any unauthorized disclosure of our material know-how or trade secrets could adversely affect our business and results of operations.

•An information technology system failure may adversely affect our business.

We rely on information technology systems, some of which are managed by third parties, to transact our business. An information technology system failure due to computer viruses, internal or external security breaches, cybersecurity attacks, power interruptions, hardware failures, fire, natural disasters, human error or other causes could disrupt our operations, lead to loss of confidential information (such as the personally identifiable information of individuals, including our employees) or intellectual property, and/or prevent us from being able to process transactions with our customers, operate our manufacturing facilities, and properly report transactions in a timely manner. Cybersecurity threats, in particular, continue to increase in sophistication. We have security processes and disaster recovery plans in place to mitigate these threats. Nonetheless, these may not be sufficient to identify a threat in a timely manner or protect our operations from such a threat, potentially resulting in financial, legal, business, or reputational damage to our company.

A significant or protracted information technology system failure may adversely affect our results of operations, financial condition, or cash flows.

Furthermore, we are subject to evolving cybersecurity and data privacy rules and regulations, such as the European Union's General Data Protection Regulation, in countries, states, and other jurisdictions where we conduct business. Any failure to comply with these rules and regulations could result in significant financial penalties and increase our cost of doing business.

•The occurrence or threat of extraordinary events, including domestic or international terrorist attacks, war, armed hostilities, or health-related epidemics, may disrupt our operations, decrease demand for our products, and increase our expenses.

Chemical-related assets may be at greater risk of future terrorist attacks than other possible targets in the United States and throughout the world. Federal legislation has imposed significant site security requirements, specifically on chemical manufacturing facilities. Federal regulations have also been enacted to increase the security of the transportation of hazardous chemicals in the United States. The enactment of further federal regulations to increase the security of the transportation of hazardous chemicals in the United States could increase our cost of doing business.

The occurrence of extraordinary events, including future terrorist attacks, the outbreak or escalation of war, armed hostilities, or a health-related epidemic cannot be predicted, but their occurrence can be expected to negatively affect the economy in general, as well as the markets for our products, and could result in production downtime. In addition, the damage from a direct attack on our facilities or other assets or on facilities or other assets used by us could include loss of life or property damage, and our insurance coverage may not be sufficient to cover all of the damage incurred or securing coverage for these types of events may be prohibitively expensive.

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•We face risks related to our foreign operations that may negatively affect our business.

In 2025, sales to customers outside of the United States accounted for approximately 61% of consolidated net sales. We do business in all major regions of the world, some of which do not have stable economies or governments. In particular, we sell and market products in countries experiencing political and/or economic instability in the Middle East, Asia Pacific, Latin America, and Europe. Our international operations are subject to international business risks, including unsettled political conditions, war, expropriation, import and export restrictions, tariffs, trade policies, increases in royalties, exchange controls, national and regional labor strikes, taxes, government royalties, inflationary or unstable economies, currency exchange rate fluctuations, and changes in laws and policies governing operations of foreign-based companies (such as restrictions on repatriation of earnings or proceeds from liquidated assets of foreign subsidiaries). The occurrence of any one or a combination of these factors may increase our costs or have other adverse effects on our business.

•The insurance we maintain may not fully cover all potential exposures.

We maintain property, business interruption, and casualty insurance, but such insurance may not cover all risks associated with the hazards of our business and is subject to limitations, including deductibles and maximum liabilities covered. We may incur losses beyond the limits, or outside the coverage, of our insurance policies, including liabilities for environmental remediation. In the future, we may not be able to obtain coverage at current levels, and our premiums may increase significantly on coverage that we maintain.

Legislative and Regulatory Risks

•Our business could be adversely affected by current and future governmental regulation.

We are subject to regulation by local, state, federal, and foreign governmental authorities. In some circumstances, before we may sell certain products, these authorities must approve these products, our manufacturing processes, and our facilities. We are also subject to ongoing reviews of our products, manufacturing processes, and facilities by governmental authorities. Any delay in obtaining or failure to obtain or maintain these approvals would adversely affect our ability to introduce new products and generate sales from those products.

New laws and regulations, including climate change regulations and global tax legislation, may be introduced in the future and could result in additional compliance costs, which could prevent or inhibit the development, distribution, and sale of our products. If we fail to comply with applicable laws and regulations, we may be subject to civil remedies, including fines, injunctions, recalls, or seizures.

We are subject to the U.S. Foreign Corrupt Practices Act, the U.K. Bribery Act, and similar anti-bribery laws in other jurisdictions which generally prohibit companies and their intermediaries from making improper payments to foreign officials for the purpose of obtaining or retaining business. We are also subject to export and import laws and regulations which restrict trading with embargoed or sanctioned countries and certain individuals. Although we have policies and procedures designed to facilitate compliance with these laws and regulations, our employees, contractors and agents may take actions in violation of our policies. Any such violation, even if prohibited by our policies, could adversely affect our business and/or our reputation.

•Legal proceedings and other claims could impose substantial costs on us.

We are involved in numerous administrative and legal proceedings that result from, and are incidental to, the conduct of our business. From time to time, these proceedings involve environmental, product liability, tetraethyl lead, premises asbestos liability, and other matters. See Item 3, “Legal Proceedings.” There is no assurance that our available insurance will cover these claims, that our insurers will not challenge coverage for certain claims, or that final damage awards will not exceed our available insurance coverage.

At any given time, we are involved in claims, litigation, administrative proceedings, and investigations of various types in a number of jurisdictions involving potential environmental liabilities, including clean-up costs associated with waste disposal sites, natural resource damages, property damage, and personal injury. We cannot assure that the resolution of these environmental matters will not have an adverse effect on our results of operations, financial condition, or cash flows.

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•Environmental matters could have a substantial negative impact on our business.

As a manufacturer and distributor of chemical products, we are generally subject to extensive local, state, federal, and foreign environmental, safety, and health laws and regulations concerning, among other things, emissions to the air; discharges to land and water; the generation, handling, treatment, and disposal of hazardous waste and other materials; and remediation of contaminated soil, as well as surface and ground water. Our operations entail the risk of violations of those laws and regulations, many of which provide for substantial fines and criminal sanctions for violations. We believe that we comply in all material respects with laws, regulations, statutes, and ordinances protecting the environment, including those related to the discharge of materials. However, we cannot assure that we have been or will be at all times in compliance with all of these requirements.

In addition, these requirements, and the enforcement or interpretation of these requirements, may become more stringent in the future. Although we cannot predict the ultimate cost of compliance with any such requirements, the costs could be material. Noncompliance could subject us to material liabilities, such as government fines, damages arising from third-party lawsuits, or the suspension and potential cessation of non-compliant operations. We may also be required to make significant site or operational modifications at substantial cost. Future developments could also restrict or eliminate the use of or require us to make modifications to our products.

There may be environmental problems associated with our properties of which we are unaware. The discovery of environmental liabilities attached to our properties could have an adverse effect on our business even if we did not create or cause the problem.

We may also face liability arising from current or future claims alleging personal injury, product liability, or property damage due to exposure to chemicals or other hazardous substances, such as premises asbestos, at or from our facilities. We may also face liability for personal injury, product liability, property damage, natural resource damage, or clean-up costs for the alleged migration of contaminants or hazardous substances from our facilities or for future accidents or spills.

In some cases, we have been identified, and in the future may be identified, as a potentially responsible party (PRP) in connection with state and federal laws regarding environmental clean-up projects. As a PRP, we may be liable for a share of the costs associated with cleaning up hazardous waste sites, such as a landfill to which we may have sent waste.

The ultimate costs and timing of environmental liabilities are difficult to predict. Liability under environmental laws relating to contaminated sites can be imposed retroactively and on a joint and several basis. A liable party could be held responsible for all costs at a site, whether currently or formerly owned or operated, regardless of fault, knowledge, timing of the contamination, cause of the contamination, percentage of contribution to the contamination, or the legality of the original disposal. We could incur significant costs, including clean-up costs, natural resource damages, civil or criminal fines and sanctions, and third-party claims, as a result of past or future violations of, or liabilities under, environmental laws.

Financial and Economic Risks

•A substantial amount of indebtedness could adversely impact our business and limit our operational and financial flexibility.

We have incurred, and may in the future incur, substantial amounts of indebtedness to support our operations, including financing acquisitions or other investment opportunities. To the degree that our indebtedness is at variable interest rates, increasing interest rates in the market will result in higher interest expense in our results of operations. Substantial amounts of indebtedness could, among other things, require us to dedicate a substantial portion of our cash flow to repaying and servicing our indebtedness, thus reducing the amount of funds available for other general corporate purposes; limit our ability to borrow additional funds necessary for working capital, capital expenditures or other general corporate purposes; and limit our flexibility in planning for, or reacting to, changes in our business.

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Our ability to make payments on or refinance our indebtedness will depend on our ability to generate cash from operations in the future. This, to a certain extent, is subject to general economic, financial, competitive, legislative, regulatory, and other factors that are beyond our control.

We cannot guarantee that our business will generate sufficient cash flow from operations or that future borrowings will be available to us under our credit facilities in an amount sufficient to enable us to repay our debt, service our indebtedness, or to fund other liquidity needs. Furthermore, substantially all of our business is conducted through our subsidiaries, and we cannot guarantee that our subsidiaries will be able to distribute funds to us for these purposes.

We may need to refinance all or a portion of our indebtedness on or before maturity. We cannot guarantee that we will be able to refinance any of our indebtedness on commercially reasonable terms or at all.

Additionally, our debt instruments contain restrictive covenants. These covenants may constrain our activities and limit our operational and financial flexibility. Failure to comply with these covenants could result in an event of default.

•We are exposed to fluctuations in foreign exchange rates, which may adversely affect our results of operations.

We conduct our business in the local currency of many of the countries in which we operate. The financial condition and results of operations of our foreign operating subsidiaries are reported in the relevant local currency and then translated to U.S. Dollars at the applicable currency exchange rate for inclusion in our consolidated financial statements. Changes in exchange rates between these foreign currencies and the U.S. Dollar will affect the recorded amounts of our assets and liabilities, as well as our revenues, costs, and operating margins. The primary foreign currencies in which we have exchange rate fluctuation exposure are the European Union Euro, British Pound Sterling, Japanese Yen, Chinese Renminbi, Indian Rupee, Singapore Dollar, Mexican Peso, Australian Dollar, and Canadian Dollar. Exchange rates between these currencies and the U.S. Dollar have fluctuated significantly in recent years and may do so in the future.

•We could be required to make additional contributions to our pension plans, which may be underfunded due to any underperformance of equity markets.

Our pension plan asset allocation is predominantly weighted towards equities. Cash contribution requirements to our pension plans are sensitive to changes in our plans’ actual return on assets. Reductions in our plans’ return on assets due to poor performance of equity markets could cause our pension plans to be underfunded and require us to make additional cash contributions.

Acquisition and Investment Risks

•We may be unable to complete a proposed acquisition transaction due to a lack of regulatory approval or the failure of one or more parties to satisfy conditions to close. In addition, we may not be able to realize the expected benefits from acquisitions or from investments in our infrastructure, or it may take longer to realize those benefits than originally planned. The inability to achieve our objectives related to these activities could result in unanticipated expenses and losses.

As part of our business growth strategy, we intend to continue pursuing acquisitions and investing in our infrastructure. Our ability to implement these components of our growth strategy will be limited by our ability to identify appropriate acquisition or joint venture candidates; our ability to complete proposed transactions, which may be subject to, among other things, regulatory approval or the parties' satisfaction of conditions required for closing; and the availability of financial resources, including cash and borrowing capacity. When we acquire new businesses or invest in infrastructure improvements (for example, building new plant facilities), we consider the benefits we expect to realize and time frames over which we will realize those benefits. The expenses incurred in completing these types of activities, the time it takes to integrate the activities into our ongoing business, or our failure to realize the expected benefits from the activities in the planned time frames could result in unanticipated expenses and losses. The process of integrating acquired operations into our existing operations may result in unforeseen operating difficulties and may require significant financial resources that would otherwise be available for the ongoing development or expansion of existing operations.

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In addition, our ability to realize the expected benefits from our recent acquisitions is subject to several factors.These include our ability to retain key personnel, our ability to maintain relationships with suppliers and customers, and our ability to integrate them into certain information technology systems, operational systems, procedures, or controls without disrupting their operations.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None.

ITEM 1C. CYBERSECURITY

Material Risks from Cybersecurity Threats

Our operations and other aspects of our business rely heavily on various information technology systems, some of which are managed by third parties. We face significant cybersecurity threats, which are continuously increasing in sophistication, including computer viruses, internal and external security breaches, and other cyber attacks. These threats could disrupt our operations, lead to the loss of confidential information (such as the personally identifiable information of individuals, including our employees), and hinder our ability to process transactions with customers, operate our manufacturing facilities, and accurately report transactions in a timely manner. To manage these cybersecurity risks, our organization leverages the National Institute of Standards and Technology (NIST) Cybersecurity Framework. We have implemented comprehensive policies and procedures that facilitate the timely identification and reporting of cyber incidents.

Additionally, we have established protective measures for the forensic analysis of cyber incidents. While we are proactive in our efforts to mitigate these threats through robust security processes and disaster recovery plans, the evolving nature of cybersecurity threats means that our systems may not always be able to identify or protect against a threat promptly or at all. As a result, there is a continuous risk of potential financial, legal, business, and reputational damage to our company stemming from cybersecurity threats.

Our Information Technology team is dedicated to and responsible for assessing and managing cybersecurity threats. Our Information Technology Director, who has over 25 years of experience in information security serving in roles of increasing responsibility, works with our cybersecurity employees to set priorities and is responsible for cybersecurity oversight and the escalation of incidents with business impact to senior leadership based on our Information Security Incident Management Policy.

We utilize specialized third-party services and tools for identifying, protecting against, and detecting cyber incidents, and also partner with external cybersecurity experts and vendors to augment our internal security team. Through these third-party services, our detection capabilities include, but are not limited to, real-time monitoring, intrusion detection systems, and advanced analytics to identify abnormal patterns of behavior. These third-party detection tools provide real-time alerts, log aggregation, and threat intelligence feeds, which are integrated into our incident response platform.

Additionally, we engage third-parties to conduct independent assessments of our cybersecurity posture that evaluate the efficiency and effectiveness of our detection capabilities, along with our response mechanisms, and overall risk management.

Third-party service providers are integral to our business operations and are incorporated into our enterprise-wide risk management program, which subjects the providers to rigorous vetting processes and ongoing oversight. We use specialized monitoring tools that evaluate the cybersecurity posture of our third-party providers using a cybersecurity scorecard. This allows us to continually assess the cybersecurity risk levels associated with these external partners.

Our approach to managing cybersecurity risks (including third-party risk) is part of a continuous improvement process, both in the context of cybersecurity and broader operational risk management. This ongoing process, which includes employee training, is aimed at routinely reviewing and, as necessary, improving our oversight processes and tools to ensure they remain effective and resilient in their management of cybersecurity risk.

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Material Impact of Cybersecurity Threats

While we have yet to experience a material cybersecurity event, we acknowledge the persistent and evolving nature of these threats, which have the potential to materially impact our business strategy, operations, and financial standing adversely. See Item 1A, "Risk Factors" under the operational risks section for more information. We maintain robust policies and procedures focused on cybersecurity incident management, ensuring timely communication and escalation to all relevant stakeholders. This enables faster response and effective communication, including public disclosure if a material cybersecurity event were to occur.

Board of Directors Oversight

The Nominating and Corporate Governance Committee of the Board of Directors (the Committee) oversees risks related to cybersecurity, including the security of corporate information and the steps management is taking to monitor and control these risks. Management regularly briefs the Committee on our cybersecurity risk profile, emerging threats, and the efficacy of our risk mitigation strategies, including our continuous improvement initiatives. These initiatives aim to enhance the resiliency of our cybersecurity program as well as our broader operational risk management strategies.

ITEM 2. PROPERTIES

Our principal operating properties are shown below. Unless indicated, we own the research, development, and testing facilities, which primarily support the petroleum additives business segment, as well as the manufacturing and distribution properties.

We own our corporate headquarters located in Richmond, Virginia, and generally lease our regional and sales offices in a number of locations worldwide.

NewMarket Development manages the real property we own in Richmond, Virginia consisting of approximately 50 acres. Our corporate offices are included in this acreage, as well as a research and testing facility and several acres dedicated to other uses. We are exploring various development opportunities for portions of the property as the demand warrants. This effort is ongoing in nature.

Production Capacity

We believe our plants and supply agreements are sufficient to meet expected sales levels. Operating rates of the plants vary with product mix and normal sales swings. We believe that our facilities are well maintained and in good operating condition.

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ITEM 3. LEGAL PROCEEDINGS

We are involved in legal proceedings that are incidental to our business and may include administrative or judicial actions. Some of these legal proceedings involve governmental authorities and relate to environmental matters. For further information, see the Environmental section in Note 21 to the Consolidated Financial Statements included in Item 8, "Financial Statements and Supplementary Data".

While it is not possible to predict or determine with certainty the outcome of any legal proceeding, we believe the outcome of any of these proceedings, or all of them combined, will not result in a material adverse effect on our consolidated results of operations, financial condition, or cash flows.

ITEM 4. MINE SAFETY DISCLOSURES

Not applicable.

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PART II

ITEM 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Our common stock, with no par value, is traded on the New York Stock Exchange (NYSE) under the symbol “NEU.” We had 1,669 shareholders of record as of January 31, 2026.

On December 12, 2024, our Board of Directors approved a share repurchase program authorizing management to repurchase up to $500 million of NewMarket's outstanding common stock beginning January 1, 2025 and until December 31, 2027, as market conditions warrant and covenants under our existing debt agreements permit. We may conduct the share repurchases in the open market, in privately negotiated transactions, through block trades, or pursuant to trading plans intended to comply with Rule 10b5-1 and/or Rule 10b-18 of the Securities Exchange Act of 1934. The repurchase program does not require us to acquire any specific number of shares and may be terminated or suspended at any time. At December 31, 2025, approximately $428 million remained available under this authorization. There were no purchases during the fourth quarter of 2025 under this authorization.

Cash dividends declared and paid totaled $11.25 per share for the year ended December 31, 2025, and $10.00 per share for the year ended December 31, 2024. The declaration and payment of dividends is subject to the discretion of our Board of Directors. Future dividends will depend on various factors, including our financial condition, earnings, cash requirements, legal requirements, restrictions in agreements governing our outstanding indebtedness, and other factors deemed relevant by our Board of Directors.

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The performance graph of the five-year cumulative total return on our common stock as compared to chemical companies in the S&P 1500 Specialty Chemicals Index and the S&P 500 is shown below. The graph assumes $100 invested on the last day of December 2020, and the reinvestment of all dividends. The graph is based on historical data and is not intended to be a forecast or indication of future performance of our common stock.

Performance Graph

Comparison of Five-Year Cumulative Total Return

Performance Through December 31, 2025

December 31,

The graph and table above are not deemed “filed” with the SEC for purposes of Section 18 of the Exchange Act or otherwise subject to the liabilities of that section, nor are they incorporated by reference into other filings made by us with the SEC.

ITEM 6. RESERVED

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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Management's Discussion and Analysis of Financial Condition and Results of Operations (MD&A) discusses NewMarket's results of operations, general financial condition, and liquidity. The MD&A should be read in conjunction with Item 1, "Business" and the Consolidated Financial Statements in Item 8, "Financial Statements and Supplementary Data." Specific Note references within this Item are to the Notes to the Consolidated Financial Statements included in Item 8, "Financial Statements and Supplementary Data."

Forward-Looking Statements

The following discussion, as well as other discussions in this Annual Report on Form 10-K, contains forward-looking statements about future events and expectations within the meaning of the Private Securities Litigation Reform Act of 1995. We have based these forward-looking statements on our current expectations and projections about future results. When we use words in this document such as “anticipates,” “intends,” “plans,” “believes,” “estimates,” “projects,” “expects,” “should,” “could,” “may,” “will,” and similar expressions, we do so to identify forward-looking statements. Examples of forward-looking statements include, but are not limited to, statements we make regarding future prospects of growth in the petroleum additives or specialty materials markets, other trends in these markets, our ability to maintain or increase our market share, and our future capital expenditure levels and our future financial results.

We believe our forward-looking statements are based on reasonable expectations and assumptions, within the bounds of what we know about our business and operations. However, we offer no assurance that actual results will not differ materially from our expectations due to uncertainties and factors that are difficult to predict and beyond our control.

Factors that could cause actual results to differ materially from expectations include, but are not limited to, the availability of raw materials and distribution systems; disruptions at production facilities, including single-sourced facilities; hazards common to chemical businesses; the ability to respond effectively to technological changes in our industries; failure to protect our intellectual property rights; sudden, sharp, or prolonged raw material price increases; competition from other manufacturers; current and future governmental regulations; the loss of significant customers; termination or changes to contracts with contractors and subcontractors of the U.S. government or directly with the U.S. government; failure to attract and retain a highly-qualified workforce; an information technology system failure or security breach; the occurrence or threat of extraordinary events, including natural disasters, terrorist attacks, wars, and health-related epidemics; risks related to operating outside of the United States, including tariffs and trade policy; political, economic, and regulatory factors concerning our products; the impact of substantial indebtedness on our operational and financial flexibility; the impact of fluctuations in foreign exchange rates; resolution of environmental liabilities or legal proceedings; limitation of our insurance coverage; our inability to realize expected benefits from investment in our infrastructure or from acquisitions, or our inability to successfully integrate acquisitions into our business; and the underperformance of our pension assets resulting in additional cash contributions to our pension plans. Risk factors are discussed in Item 1A. “Risk Factors.”

You should keep in mind that any forward-looking statement made by us in this discussion or elsewhere speaks only as of the date on which we make it. New risks and uncertainties arise from time to time, and it is impossible for us to predict these events or how they may affect us. We have no duty to, and do not intend to, update or revise the forward-looking statements in this discussion after the date hereof, except as may be required by law. In light of these risks and uncertainties, any forward-looking statement made in this discussion or elsewhere might not occur.

OVERVIEW

When comparing the results of the petroleum additives segment for 2025 with 2024, net sales declined 3.9%, resulting primarily from lower product shipments. Petroleum additives operating profit decreased 12.1% when comparing the 2025 and 2024 periods, primarily reflecting lower product shipments and selling prices, as well as higher operating costs, which were partially offset by lower raw material costs. In addition to lower production at our manufacturing plants, the higher operating costs included higher technology investments for research, development and testing during the 2025 period as compared to the 2024 period, as well as one-time charges related to network optimization efforts.

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We completed the acquisition of Calca on October 1, 2025 and the acquisition of AMPAC on January 16, 2024, both of which are part of the specialty materials segment. See Note 2 for further information on the acquisitions. The 2025 and 2024 periods only include the results of AMPAC and Calca for the periods we owned each company. The specialty materials segment reported both higher net sales and higher operating profit for 2025 as compared to 2024.

We continue to monitor the uncertain macroeconomic environment in which we operate, particularly the changes in international trade relations and tariffs, and assess the potential impacts to our operations. These impacts could include supply chain disruptions, lower customer demand, and higher costs. Investing in technology to meet customer needs, enhancing our operational efficiency, and improving our portfolio profitability will remain priorities.

Despite the challenging economic environment, our financial position remains strong. We have sufficient access to capital, if needed, and do not anticipate any issues with meeting the covenants for all our debt agreements for the foreseeable future.

Our business typically generates significant amounts of cash beyond its operational needs. We continue to invest in and manage our business for the long-term with the goal of helping our customers succeed in their marketplaces. Our investments continue to be in organizational talent, technology development and processes, and global infrastructure.

RESULTS OF OPERATIONS

Management's discussion and analysis of our results of operations is presented below for the comparative periods of 2025 versus 2024. The discussion and analysis of our results of operations for 2024 compared to 2023 is available in Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2024.

Net Sales

Our consolidated net sales for 2025 amounted to $2.7 billion, a decrease of $61 million, or 2.2%, from 2024.

No single customer accounted for 10% or more of our total net sales in 2025, 2024, or 2023.

The following table shows net sales by segment and product line for each of the last three years. The net sales in the table below for the specialty materials segment include sales since the acquisitions of Calca on October 1, 2025 and AMPAC on January 16, 2024.

Years Ended December 31,

Petroleum additives

Petroleum Additives -The regions in which we operate include North America (the United States and Canada), Latin America (Mexico, Central America, and South America), Asia Pacific, and the Europe/Middle East/Africa/India (EMEAI) region. The percentage of net sales being generated in the regions has remained fairly consistent over the past three years, with some limited fluctuation due to various factors, including the impact of regional economic trends. In 2025, North America represented approximately 40% of our petroleum additives net sales, while EMEAI contributed approximately 30%, Asia Pacific approximately 20%, and Latin America the remaining amount. As shown in the table above, the percentage of lubricant additives net sales and fuel additives net sales compared to total petroleum additives net sales have remained substantially consistent over the past three years.

Petroleum additives net sales for 2025 of $2.5 billion were 3.9% lower than 2024. Decreases in Asia Pacific of 10.3% and North America of 6.2% were partially offset by increases of 2.4% in EMEAI and 0.8% in Latin America.

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The approximate components of the petroleum additives decrease in net sales of $102 million when comparing 2025 to 2024 are shown below in millions.

Net sales for the year ended December 31, 2024 $ 2,636

Lubricant additives shipments (88)

Fuel additives shipments (13)

Selling prices, including product mix (6)

Foreign currency impact, net 5

Net sales for the year ended December 31, 2025 $ 2,534

When comparing petroleum additives net sales for 2025 with 2024, the primary driver was lower product shipments in both lubricant additives and fuel additives, along with a smaller unfavorable impact from lower selling prices.

On a worldwide basis, when comparing 2025 with 2024, the volume of product shipments for petroleum additives was 4.9% lower with decreases in both lubricant additives and fuel additives but primarily driven by lower lubricant additives shipments. Both the North America and Asia Pacific regions reported decreases in lubricant additives shipments, which were partially offset by increases in the EMEAI and Latin America regions. The Asia Pacific and Latin America regions reported increases in fuel additives shipments, which were more than offset by decreases in the North America and EMEAI regions. Overall, the decrease in product shipments reflects some softness in the market, as well as our strategic decision to examine and reduce low-margin business.

The primary foreign currencies in which we transact include the Euro, Pound Sterling, Japanese Yen, Chinese Renminbi, and India Rupee. Comparing 2025 and 2024, the United States Dollar weakened against the Euro, Pound Sterling, and Yen, while it strengthened against the Renminbi and Rupee, all combined resulting in the favorable impact to net sales. The favorable dollar impact from foreign currency was primarily from the Euro, which was partially offset by the unfavorable impact from the Renminbi and Rupee.

Specialty Materials - The specialty materials segment comprises the operations of AMPAC and Calca, both of which operate predominantly in the North America region. Total net sales for the specialty materials segment were $182 million for 2025 and $141 million for 2024. In addition to the inclusion of Calca in 2025 net sales, the increase between 2025 and 2024 resulted primarily from increased shipment volumes.

All Other- The “All other” category includes the operations of the antiknock compounds business, as well as certain contracted manufacturing and related services associated with Ethyl and did not have a material impact to consolidated net sales when comparing 2025 and 2024.

Segment Operating Profit

NewMarket evaluates the performance of the petroleum additives and specialty materials businesses based on segment operating profit. NewMarket Services expenses are charged to NewMarket and each subsidiary pursuant to services agreements between the companies. Depreciation on segment property, plant, and equipment, as well as amortization of segment intangible assets and lease right-of-use assets, is included in segment operating profit.

The following table reports segment operating profit for the last three years. The amounts for the specialty materials segment include operating profit since the acquisitions of Calca on October 1, 2025 and AMPAC on January 16, 2024. A reconciliation of segment operating profit to income before income tax expense is in Note 5.

Years Ended December 31,

Specialty materials $ 47 $ 17 $ 0

All other $ (5) $ (2) $ (5)

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Petroleum Additives - Petroleum additives segment gross profit decreased $60 million, and segment operating profit decreased $72 million when comparing 2025 to 2024. The following table presents the petroleum additives segment's cost of goods sold as a percentage of net sales and its operating profit margin.

Years Ended December 31,

Cost of goods sold as a percentage of net sales 69.0 % 68.0 % 71.2 %

While operating margins will fluctuate from quarter to quarter due to multiple factors, we believe the fundamentals of our business and industry as a whole are unchanged.

When comparing 2025 and 2024, the decrease in both gross profit and operating profit primarily includes the unfavorable impacts of lower product shipments and selling prices, as well as higher operating costs. The increased operating costs result primarily from lower production at our manufacturing plants and an increase in technology investments, as well as one-time charges related to our efforts to become more efficient by optimizing our global manufacturing network. These factors were partially offset by lower raw material costs.

The petroleum additives segment's selling, general, and administrative expenses (SG&A) increased by $5 million, or 3.8%, in 2025 compared to 2024. SG&A as a percentage of net sales was 5.2% in 2025 and 4.8% in 2024. Our SG&A costs are primarily personnel-related and include salaries, benefits, and other costs associated with our workforce, including travel-related expenses. While personnel-related costs fluctuate from year to year, there were no significant changes in the drivers of these costs when comparing 2025 and 2024.

Our investment in petroleum additives research, development, and testing (R&D) increased approximately $7 million when comparing 2025 with 2024. As a percentage of net sales, R&D was 5.2% in 2025 and 4.7% in 2024. Our R&D investments reflect our efforts to support the development of solutions that meet our customers' needs, meet new and evolving standards, and support our expansion into new product areas. Our approach to R&D investments, as it is with SG&A costs, is one of purposeful spending on programs to support our current product base and to ensure that we develop products to support our customers' programs in the future. R&D investments include personnel-related costs, as well as costs for internal and external testing of our products. Substantially all investments in new product development are incurred in the United States and the United Kingdom (U.K.), with approximately 70% of total R&D attributable to the North America and EMEAI regions. The remaining R&D is attributable to the Asia Pacific and Latin America regions and represents customer technology support services in those regions. All of our consolidated R&D investment is related to the petroleum additives segment.

Specialty Materials - The specialty materials segment reported operating profit of $47 million for 2025 as compared to $17 million for 2024. The 2025 and 2024 periods only included the results of AMPAC and Calca for the period we owned each company - since January 16, 2024 for AMPAC and since October 1, 2025 for Calca.

The specialty materials results for the 2024 period include the sale of AMPAC finished goods inventory that we acquired at closing. The acquired inventory was recorded at fair value on the acquisition date and sold during 2024, generating no margin. The remaining increase in specialty materials operating profit for the year comparison resulted from the same factors as those outlined in the net sales discussion.

We may experience substantial variation in quarterly results for the specialty materials segment on an ongoing basis due to the nature of its business.

The following discussion references certain captions on the Consolidated Statements of Income.

Interest and Financing Expenses

Interest and financing expenses were $40 million in 2025 and $57 million in 2024. The decrease in interest and financing expense between 2025 and 2024 resulted primarily from lower average debt outstanding, along with a lower average interest rate.

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Other Income (Expense), Net

Other income (expense), net reflected income of $57 million in 2025 and $51 million in 2024. The amounts for both periods included the components of net periodic benefit cost (income), except for service costs, from defined benefit pension and postretirement plans, which also represent most of the difference between the two years. See Note 18 for further information on total periodic benefit cost (income).

Income Tax Expense

Income tax expense was $142 million in 2025 and $122 million in 2024. The effective tax rate was 25.3% in 2025 and 20.8% in 2024. When comparing 2025 and 2024, income tax expense increased $25 million due to the higher effective tax rate and decreased $5 million due to lower income before income taxes.

The increase in the effective tax rate was primarily due to a lower foreign derived intangible income deduction and an increase in U.S. state tax expense in 2025 as compared to 2024.

The One Big Beautiful Bill Act (OBBBA) was enacted in the United States on July 4, 2025. The OBBBA includes significant provisions, such as the permanent extension of certain expiring provisions of the Tax Cuts and Jobs Act, modifications to the international tax framework, and the restoration of favorable tax treatment for certain business provisions, including permanently restoring 100 percent bonus depreciation for qualifying property and reinstating the ability for entities to immediately expense domestic research and development expenditures. These provisions will favorably impact our U.S. federal cash taxes.

The OBBBA has multiple effective dates, with certain provisions effective in 2025 and others implemented through 2027. We are continuing to assess the impact of the provisions of the OBBBA that are effective in future years.

CASH FLOWS DISCUSSION

We generated cash from operating activities of $569 million in 2025 and $520 million in 2024.

During 2025, we used the $569 million of cash generated from operating activities to acquire Calca for $213 million (net of $6 million cash acquired), pay dividends of $106 million, fund capital expenditures of $78 million, and repurchase shares of our common stock for $77 million. We also paid off the $250 million term loan and made a principal payment of $50 million on the 3.78% senior notes. These payments were partially offset by additional net borrowings of $211 million on the revolving credit facility. Cash flows from operating activities included an increase of $22 million from lower working capital requirements, which is further discussed in the Working Capital section below, and a decrease of $10 million for cash contributions to our pension and postretirement plans.

During 2024, we used the $520 million of cash generated from operating activities, along with proceeds from the term loan and net borrowings of $77 million on the revolving credit facility to acquire AMPAC for $681 million (net of $16 million cash acquired), pay dividends of $96 million, fund capital expenditures of $57 million, and repurchase shares of our common stock for $32 million. Cash flows from operating activities included a decrease of $23 million from higher working capital requirements and a decrease of $12 million for cash contributions to our pension and postretirement plans.

FINANCIAL POSITION AND LIQUIDITY

Cash

At December 31, 2025, we had cash and cash equivalents of $77.6 million as compared to $77.5 million at the end of 2024.

Cash and cash equivalents held by our foreign subsidiaries amounted to approximately $68 million at December 31, 2025 and $71 million at December 31, 2024. Periodically, we repatriate cash from our foreign subsidiaries to the United States through intercompany dividends and loans. We do not anticipate significant tax consequences of future distributions of foreign earnings.

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A portion of our foreign cash balances is associated with earnings that we have asserted are indefinitely reinvested. We plan to use these indefinitely reinvested earnings to support growth outside of the United States through funding of operating expenses, research and development expenses, capital expenditures, and other cash needs of our foreign subsidiaries.

Debt

A summary of our debt instruments follows. A full discussion is in Note 14.

2.70% Senior Notes - On March 18, 2021, we issued $400 million aggregate principal amount of 2.70% senior notes due 2031 at an issue price of 98.763%. We used the net proceeds from the offering for the repayment and redemption of our 4.10% senior notes and for general corporate purposes. We incurred financing costs in 2021 of approximately $4 million related to the 2.70% senior notes, which are being amortized over the term of the notes. We were in compliance with all covenants under the indenture governing the 2.70% senior notes as of December 31, 2025 and December 31, 2024.

3.78% Senior Notes -On January 4, 2017, we issued $250 million in senior unsecured notes in a private placement with The Prudential Insurance Company of America and certain other purchasers. These notes bear interest at 3.78% with interest payable semiannually. We have made two principal payments of $50 million each on January 4, 2025 and January 5, 2026. We have three remaining principal payments of $50 million due January 4 of each year through 2029. We have the right to make optional prepayments on the notes at any time, subject to certain limitations. We were in compliance with all covenants under the 3.78% senior notes as of December 31, 2025 and December 31, 2024.

Term Loan - On January 22, 2024, we entered into a credit agreement for an unsecured $250 million term loan (the Term Loan Credit Agreement), which had a maturity date of January 22, 2026. We borrowed the entire $250 million available under the Term Loan Credit Agreement and paid financing costs of $0.4 million, which were amortized over the term that principal was outstanding under the agreement. Under the agreement, we were required to repay the principal amount borrowed under the term loan in full at maturity. Subject to the conditions set forth in the Term Loan Credit Agreement, we had the option to prepay, without penalty, amounts borrowed under the term loan, together with any accrued and unpaid interest, prior to maturity. Any amounts prepaid prior to maturity were not available for additional borrowings by us. We repaid the Term Loan Credit Agreement in full during 2025.

The Term Loan Credit Agreement contained certain customary covenants, including financial covenants, which required NewMarket to maintain a consolidated Leverage Ratio (as defined in the Term Loan Credit Agreement) of no more than 3.75 to 1.00 except during an Increased Leverage Period (as defined in the Term Loan Credit Agreement). We were in compliance with all covenants under the term loan at the time we repaid it in 2025 and as of December 31, 2024.

Revolving Credit Facility - On January 22, 2024, we entered into a credit agreement for a $900 million revolving credit facility (the Revolving Credit Agreement). The revolving credit facility matures on January 22, 2029 and includes a $500 million sublimit for multicurrency borrowings, an initial letter of credit sublimit of $25 million, and a $20 million sublimit for swingline loans. The Revolving Credit Agreement includes an expansion feature allowing us, subject to certain conditions, to request an increase in the aggregate amount of the revolving credit facility or obtain incremental term loans in an amount up to $450 million. We may also request an extension of the maturity date as provided for in the Revolving Credit Agreement. Certain of our foreign subsidiaries may, from time to time, become borrowers under the Revolving Credit Agreement. The obligations under the Revolving Credit Agreement are unsecured and are fully and unconditionally guaranteed by NewMarket.

Concurrently with entering into the Revolving Credit Agreement, we terminated our former revolving credit facility dated as of March 5, 2020. Upon termination, we repaid the amount then outstanding under the former revolving credit facility, plus accrued and unpaid interest.

Outstanding borrowings under the revolving credit facility amounted to $288 million at December 31, 2025 and $77 million at December 31, 2024. Outstanding letters of credit under the revolving credit facility amounted to approximately $4 million at both December 31, 2025 and December 31, 2024. The unused portion of the revolving credit facility amounted to $608 million at December 31, 2025 and $819 million at December 31, 2024.

The average interest rate for borrowings under the revolving credit facility was 5.3% during 2025 and 6.5% during 2024.

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The Revolving Credit Agreement contains certain customary covenants, including financial covenants, which require us to maintain a consolidated Leverage Ratio (as defined in the Revolving Credit Agreement) of no more than 3.75 to 1.00 except during an Increased Leverage Period (as defined in the Revolving Credit Agreement). The Leverage Ratio was 1.27 at December 31, 2025 and 1.33 at December 31, 2024. We were in compliance with all covenants under the revolving credit facility as of December 31, 2025 and December 31, 2024.

Other Borrowings -Two of our subsidiaries, one in Singapore and one China, have access to separate short-term lines of credit of $10 million each. There was no activity on these lines of credit in 2025 or 2024.

***

We had long-term debt of $883 million at December 31, 2025 and $971 million at December 31, 2024. As a percentage of total capitalization (total long-term debt and shareholders’ equity), our total long-term debt percentage decreased from 39.9% at the end of 2024 to 33.2% at the end of 2025. The change resulted from the increase in shareholders' equity along with a net decrease in outstanding long-term debt. The increase in shareholders’ equity primarily reflects our earnings, favorable impact from foreign currency translation adjustments, and an increase in the funded position of our retirement plans partially offset by repurchases of shares of our common stock and dividend payments. Generally, we repay any outstanding long-term debt with cash from operations or refinancing activities.

Working Capital

Including cash and cash equivalents and the impact of foreign currency on the balance sheet, at December 31, 2025, we had working capital of $640 million, resulting in a current ratio of 2.53 to 1. Our working capital at December 31, 2024 on the same basis was $655 million, resulting in a current ratio of 2.75 to 1.

The working capital of Calca is included in our consolidated balance sheet at December 31, 2025. Excluding the impact of Calca working capital, the most significant change in working capital since December 31, 2024 included increases in both trade and other accounts receivable and accrued expenses.

The increase in trade and other accounts receivable primarily represents a short-term income tax receivable as a result of the enactment of the OBBBA in July 2025. The OBBBA provided for immediate expensing of domestic research and development expenditures and 100 percent bonus depreciation on qualifying property, with retroactive application to January 2025. The increase in accrued expenses is primarily the result of customer contract liabilities.

Capital Expenditures

Capital expenditures were $78 million for 2025 and $57 million for 2024. We estimate capital expenditures in 2026 will be in the range of $100 million to $150 million as we anticipate spending on several improvements to our manufacturing and R&D infrastructure around the world.

Included in the expected capital expenditures for 2026 is a capital investment to expand AMPAC's ammonium perchlorate production capabilities in support of growing solid rocket motor demand. The project of up to $100 million, which began in 2025, is currently scheduled to be completed towards the end of 2026 and includes the construction of an additional production line, increasing capacity by more than 50%. The increased capacity will allow AMPAC to meet the anticipated future demand of U.S. military and space launch programs, while also addressing the needs of U.S. allies in these critical areas.

We expect to continue to finance capital spending through cash provided from operations, as well as with borrowing available under our revolving credit facility.

Environmental Expenses

We spent approximately $44 million in 2025 and $37 million in 2024 for ongoing environmental operating and clean-up costs, excluding depreciation of previously capitalized expenditures. These environmental operating and clean-up expenses are primarily included in cost of goods sold. We expect to continue to fund these costs through cash provided by operations.

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Liquidity and Contractual Obligations

We have both current and long-term obligations that have known payment streams and are discussed throughout this Annual Report on Form 10-K. These include debt-related obligations, lease obligations, purchase commitments, including those for property, plant, and equipment, contributions to pension and postretirement benefit plans, and environmental dismantling and decontamination.

The debt-related contractual obligations include both principal payments on outstanding long-term debt and the related interest payments. The maturity dates and interest rates, as well as information on the repayment of the principal on our long-term debt is detailed above in the Debt section, as well as in Note 14. At December 31, 2025, all of our long-term debt was at fixed rates, except for the revolving credit facility. A discussion of interest rate sensitivity is in Item 7A. Interest is paid semi-annually on our fixed rate long-term debt agreements.

Note 17 provides information by year on our lease obligations which have commenced, as well as any lease commitments which have not yet commenced. Note 18 includes information on contributions to pension and postretirement benefit plans, as well as benefit payments to participants. Benefit payments under these plans are predominantly paid from assets held in trust. Further information on purchase commitments, including those for purchases of property, plant, and equipment, is in Note 21.

The annual operating expenses and capital expenditures associated with compliance with environmental, health, and safety regulations are included in Item 1, Governmental and Environmental Regulations. In addition to these costs, there are expected cash flows for dismantling and decontamination of environmental sites. At December 31, 2025, these costs were estimated at approximately $1.0 million to $1.5 million in each of 2026 through 2029 and $9 million thereafter.

We expect that cash from operations, together with borrowing available under our credit facilities, will continue to be sufficient for our operating needs and planned capital expenditures for both a short-term and long-term horizon.

Pension and Postretirement Benefit Plans

Our U.S. and foreign benefit plans are discussed separately below. The information below for our U.S. plans applies to all of our U.S. benefit plans on a combined basis. Our foreign plans are quite diverse, and the actuarial assumptions used by the various foreign plans are based upon the circumstances of each particular country and retirement plan. We use a December 31 measurement date to determine our net periodic benefit cost (income) for all of our pension and postretirement benefit plans and related financial disclosure information. Additional information on our pension and postretirement plans is in Note 18.

U.S. Pension and Postretirement Benefit Plans—The average remaining service period of active participants for our U.S. plans is approximately 13 years, while the average remaining life expectancy of inactive participants is approximately 22 years. We utilize the sex distinct Pri-2012 table with separate rates for annuitants, non-annuitants, and contingent annuitants, projected generationally using Scale MP-2021 in determining the impact of mortality on the U.S. benefit plans in our financial statements.

Investment Return Assumptions and Asset Allocation - We periodically review our assumptions for the long-term expected return on pension plan assets. As part of the review and to develop expected rates of return, we considered an analysis of expected returns based on the U.S. plans’ asset allocation as of both January 1, 2026 and January 1, 2025. This analysis reflects our expected long-term rates of return for each significant asset class or economic indicator. The range of returns developed relies both on forecasts and on broad-market historical benchmarks for expected return, correlation, and volatility for each asset class. The asset allocation for our U.S. pension plans is predominantly weighted toward equities. Through the ongoing monitoring of our investments and review of market data, we have determined that we should maintain the expected long-term rate of return for our U.S. pension plans at 8.0% at December 31, 2025.

An actuarial gain on the assets occurred during 2025 and 2024 as the actual investment return for all of our U.S. qualified pension plans exceeded the expected return by approximately $37 million in 2025 and $54 million in 2024. Investment gains and losses are recognized in earnings on an amortized basis over a period of 5 years. The amortization of the actuarial net gain is expected to be approximately $5 million in 2026 resulting primarily from the actuarial gain related to the investment gains on plan assets. We expect that there will be continued volatility in net periodic benefit cost

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(income) for our pension plans as actual investment returns vary from the expected return, but we continue to believe the potential long-term benefits justify the risk premium for equity investments.

At December 31, 2025, our expected long-term rate of return on our postretirement plans was 4.0%. This rate varies from the pension rate of 8.0% primarily because of the difference in investment of plan assets. The assets of the postretirement plan are held in an insurance contract, which results in a lower assumed rate of investment return.

We expect to have net periodic benefit income for our pension and postretirement plans during 2026, as the expected return on assets and amortization is higher than the offsetting benefit costs. Net periodic benefit cost (income) for the pension and the life insurance portion of postretirement plans is sensitive to changes in the expected return on assets. For example, decreasing the expected rate of return by 100 basis points to 7.0% for pension assets and 3.0% for postretirement benefit assets (while holding other assumptions constant) would reduce the forecasted 2026 income for our U.S. pension and postretirement plans by approximately $8 million. Similarly, a 100 basis point increase in the expected rate of return to 9.0% for pension assets and 5.0% for postretirement benefit assets (while holding other assumptions constant) would increase forecasted 2026 pension and postretirement income by $8 million.

Discount Rate Assumption - We develop the discount rate assumption by determining the single effective discount rate for a unique hypothetical bond portfolio constructed from investment-grade bonds that, in the aggregate, match the projected cash flows of each of our retirement plans. The discount rate is developed based on the hypothetical bond portfolio on the last day of December. The discount rate at December 31, 2025 was 5.875% for all plans.

Net periodic benefit cost (income) for pension and postretirement benefit plans is also sensitive to changes in the discount rate. For example, decreasing the discount rate by 100 basis points to 4.875% (while holding other assumptions constant) would reduce the forecasted 2026 income for our U.S. pension and postretirement benefit plans by approximately $6 million. A 100 basis point increase in the discount rate to 6.875% (while holding other assumptions constant) would increase forecasted 2026 pension and postretirement benefit income by approximately $5 million.

Rate of Projected Compensation Increase - We have maintained our rate of projected compensation increase at December 31, 2025 at 3.5%. The rate assumption was based on an analysis of our projected compensation increases for the foreseeable future.

Liquidity - Cash contribution requirements to the pension plan are sensitive to changes in assumed interest rates and investment gains or losses in the same manner as pension expense. While we do not expect to make a cash contribution to our U.S. qualified pension plans, we expect our aggregate cash contributions to all U.S. pension plans will be approximately $4 million in 2026. We expect our contributions to the postretirement benefit plans will be approximately $1 million in 2026.

Foreign Pension Benefit Plans - Our foreign pension plans are quite diverse. The following information applies only to our U.K. pension plan, which represents the majority of the amounts recorded in our financial statements for our foreign pension plans. The average remaining service period of active participants for our U.K. plan is approximately 15 years, while the average remaining life expectancy of inactive participants is 20 years. In determining the impact of mortality on the U.K. pension plan in our financial statements, we utilize the S4PxA mortality tables weighted by 99% for male members and 88% for female members and S4DxA mortality tables weighted by 106% for male dependents and 107% for female dependents. Future projected improvements in life expectancy are allowed for in line with the CMI 2024 model with an initial addition to mortality improvements of 0.2% and a half-life parameter of 1 year with a long-term rate of improvement of 1.65% per year for males and 1.25% per year for females based on the membership of the plan.

Investment Return Assumptions and Asset Allocation - We periodically review our assumptions for the long-term expected return on the U.K. pension plan assets. The expected long-term rate of return is based on both the asset allocation and yields available in the U.K. markets.

The target asset allocation in the U.K. is 40% in pooled equities funds, 40% in pooled government bonds, and 20% in pooled diversified growth funds. The actual allocation at the end of 2025 was 53% in pooled equities funds, 25% in pooled government bonds, and 22% in pooled diversified growth funds. Based on the actual asset allocation and the expected yields available in the U.K. markets, the expected long-term rate of return for the U.K. pension plan was 7.8% at December 31, 2025.

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An actuarial gain on the assets occurred during both 2025 and 2024 as the actual investment return exceeded the expected investment return by approximately $6 million in 2025 and $1 million in 2024. Actuarial gains of $6 million occurred during 2025 and $16 million during 2024 on plan liabilities primarily due to changes in the assumptions. Investment and liability gains and losses are recognized in earnings on an amortized basis over a period of years. The combined net gains result in an expected amortization of $1 million in 2026. We expect that there will be continued volatility in the net periodic benefit cost (income) for our U.K. pension plan as actual investment returns vary from the expected return, but we continue to believe the potential benefits justify the risk premium for the target asset allocation.

We expect to have pension income during 2026 related to our U.K. plan, as the expected return on assets is higher than the offsetting pension costs. Net periodic benefit cost (income) for the U.K. pension plan is sensitive to changes in the expected return on assets. For example, decreasing the expected rate of return by 100 basis points to 6.8% (while holding other assumptions constant) would decrease the forecasted 2026 income for our U.K. pension plan by approximately $2 million. Similarly, a 100 basis point increase in the expected rate of return to 8.8% (while holding other assumptions constant) would increase forecasted 2026 pension income by approximately $2 million.

Discount Rate Assumption - We utilize a yield curve based on AA-rated corporate bond yields in developing a discount rate assumption. The yield appropriate to the duration of the U.K. plan liabilities is then used. The discount rate at December 31, 2025 was 5.60%.

Net periodic benefit cost (income) for the U.K. pension plan is also sensitive to changes in the discount rate. For example, decreasing the discount rate by 100 basis points to 4.60% (while holding other assumptions constant) would decrease the forecasted 2026 income for our U.K. pension plans by approximately $300 thousand. A 100 basis point increase in the discount rate to 6.60% (while holding other assumptions constant) would increase forecasted 2026 pension income by approximately $300 thousand.

Rate of Projected Compensation Increase - Our rate of projected compensation increase at December 31, 2025 is 3.5%. The rate assumption was based on an analysis of our projected compensation increases for the foreseeable future.

Liquidity - Cash contribution requirements to the U.K. pension plan are assessed every three years by a formal actuarial valuation, which will be completed in 2026. Contributions are sensitive to the assumptions adopted and market conditions at each assessment date. We expect our aggregate U.K. cash contributions will be approximately $3 million in 2026.

OUTLOOK

Our goal is to provide a 10% compounded return per year for our shareholders over any ten-year period (defined as earnings per share growth plus dividend yield), although we may not necessarily achieve a 10% return each year. We continue to have confidence in our customer-focused strategy and approach to the market. We believe the fundamentals of how we run our business - a long-term view, safety-first culture, customer-focused solutions, technology-driven product offerings, and world-class supply chain capability - will continue to be beneficial for all of our stakeholders over the long term.

We expect our petroleum additives segment will continue to experience impacts to its operating performance during 2026 due to market softness and the uncertain global economic environment in which we operate. Nonetheless, we anticipate continued solid results from this segment in 2026. We will continue to focus on investing in technology for our customers, cost control, and operating profit margin management, while advancing our initiatives to build a global manufacturing network that will enable more efficient product delivery to our customers in the years ahead.

Over the past several years we have made significant investments in our petroleum additives business as the industry fundamentals remain positive. These investments have been, and will continue to be, focused on operational efficiencies, organizational talent, and technology development and processes, as well as global infrastructure, including technical centers, production capabilities and geographic expansion. We intend to utilize these investments to improve our ability to deliver the solutions that our customers value, expand our global reach, and enhance our operating results. We will continue to invest in our capabilities to provide even better value, service, technology, and customer solutions.

In addition to the ongoing investments we make in our petroleum additives business, we have, since 2024, completed the acquisition of two companies - AMPAC and Calca - which constitute our specialty materials segment. Through these

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acquisitions and our investments in expanding capacity at both operations, we have committed approximately $1 billion to this resilient, high-technology segment. We continue to focus on the integration of these companies into our business, and we anticipate solid results from both companies. We may experience substantial variation in quarterly results for the specialty materials segment on an ongoing basis due to the nature of the business, including any impact from shutdowns of the U.S. government.

Our business typically generates significant amounts of cash beyond its operational needs. We regularly review our many internal opportunities to utilize excess cash from technological, geographic, production capability, and product line perspectives. We believe our capital spending is creating the capability we need to grow and support our customers worldwide, and our research and development investments are positioning us well to provide added value to our customers.

While our recent acquisitions of AMPAC and Calca were outside of our core petroleum additives business, we believe both presented an excellent opportunity to provide long-term value for our shareholders. Nonetheless, our primary focus in the acquisition area remains on the petroleum additives industry. It is our view that the petroleum additives industry will provide the greatest opportunity for solid returns on our investments while minimizing risk. We remain focused on this strategy and will evaluate any future opportunities. We will continue to evaluate all alternative uses of cash to enhance shareholder value, including stock repurchases and dividends.

CRITICAL ACCOUNTING POLICIES AND ESTIMATES

The following discussion highlights some of the more critical areas where a significant change in facts and circumstances in our operating and financial environment could cause a change in future reported financial results.

Income Taxes

We file United States, foreign, state, and local income tax returns. Significant judgment is required in determining our worldwide provision for income taxes and recording the related tax assets and liabilities. Any significant impact as a result of changes in underlying facts, laws, tax rates, or tax audits could lead to adjustments to our income tax expense, effective tax rate, financial position, or cash flow.

Deferred income taxes are provided for the estimated income tax effect of temporary differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities, as well as for net operating losses and tax credit carryforwards. When recording these deferred tax assets and liabilities, we must estimate the tax rates we expect will apply to taxable income in the periods in which the deferred tax liability or asset is expected to be settled or realized. In addition, we may record valuation allowances to reduce deferred tax assets if it is more likely than not that some portion or all of the deferred tax assets will not be realized. Judgment is required as we consider the scheduled reversal of deferred tax assets and liabilities, projected future taxable income, and tax planning strategies in making this assessment. If our estimates and assumptions change from those used when we recorded deferred tax assets and liabilities, the effect on our results of operations and financial position could be material.

The income tax returns for our entities in the United States and in foreign jurisdictions are open for examination by tax authorities. We assess our income tax positions and record a liability for all years open for examination based upon our evaluation of the facts, circumstances, and information available at the reporting date. The economic benefit associated with a tax position will be recognized only if we determine it is more likely than not to be upheld on audit. Although we believe our estimates and judgments are reasonable, actual results could differ, resulting in gains or losses that may be material to our results of operations and financial position.

At each interim reporting period, we estimate an effective income tax rate that is expected to be applicable for the full year. Our provision for income taxes is impacted by the income tax rates of the countries where we operate. A change in the geographical source of our income can affect the effective tax rate. Significant judgment is involved regarding the application of global income tax laws and regulations when projecting the jurisdictional mix of income. Additionally, interpretations of tax laws, court decisions, or other guidance provided by taxing authorities influence our estimate of the effective income tax rate. As a result, our actual effective income tax rate and related income tax liabilities may differ materially from our estimated effective tax rate and related income tax liabilities.

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Intangibles (net of amortization) and Goodwill

We have certain intangibles amounting to $517 million and goodwill amounting to $424 million at December 31, 2025 that are discussed in Note 11. Of these intangibles and goodwill, $124 million is attributable to the petroleum additives segment and $817 million to the specialty materials segment. The finite-lived intangible assets are being amortized over remaining useful lives up to approximately 20 years. Water rights are indefinite-lived and non-amortizing.

We estimate fair value for these identifiable intangibles using an income valuation approach for customer bases, backlog, formulas and technology, and trademarks and trade names. The cash flow projections include significant judgments and assumptions relating to revenue growth rates; earnings before interest, taxes, depreciation, and amortization; discount rate; contributory asset charges; customer attrition rate; and royalty rates, as applicable. We use a market valuation approach for estimating water rights and our significant judgments and assumptions included comparable sales data.

We continue to assess the market related to the intangibles and goodwill, as well as their specific values and evaluate the intangibles and goodwill for any potential impairment when significant events or circumstances occur that might impair the value of these assets. We have concluded the values are appropriate, as are the amortization periods for the intangibles. However, if conditions were to substantially deteriorate in the petroleum additives or specialty materials markets, it could possibly cause a decrease in the estimated useful lives of the intangible assets or result in a noncash write-off of all or a portion of the intangibles and goodwill carrying amounts. A reduction in the amortization period or write-off of the intangibles would have no effect on cash flows. We do not anticipate such a change in the market conditions in the near term.

Pension Plans and Postretirement Benefits

The impact of the pension and postretirement benefit plan obligations recorded in the financial statements is dependent upon utilizing actuarial methods and requires the use of estimates and assumptions. These assumptions include the discount rate, rate of projected compensation increase, and the expected long-term rate of return on plan assets. A change in any of these assumptions could cause different results for the plans and therefore, impact our results of operations, cash flows, and financial condition. Further discussion on how we develop these assumptions and the effect of changes in these assumptions on our financial results is provided in the Financial Position and Liquidity section of Item 7. In addition, information is provided on the pension and postretirement plans in Note 18.

Environmental and Legal Proceedings

We have disclosed our environmental matters in Item 1 of this Annual Report on Form 10-K, as well as in Note 21. Our estimates for costs that will be incurred to satisfy our obligations related to environmental matters are affected by many variables, including our judgment regarding the extent of remediation that will be required, future changes in and enforcement and interpretation of laws and regulations, current and future technology available, and timing of remediation activities. While we currently do not anticipate significant changes to the many factors that could impact our environmental requirements, we continue to keep our accruals consistent with these requirements as they change.

Also, as noted in the discussion of Legal Proceedings in Item 3 of this Annual Report on Form 10-K, while it is not possible to predict or determine with certainty the outcome of any legal proceeding, it is our opinion, based on our current knowledge, that we will not experience any material adverse effects on our results of operations, cash flows, or financial condition as a result of any pending or threatened proceeding.

RECENT ACCOUNTING PRONOUNCEMENTS

For a discussion of recently issued accounting standards, see Note 23.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

We are exposed to market risk factors, including interest rates, foreign currency rates, and changes in the cost of raw materials. These risk factors may affect our results of operations, cash flows, and financial position.

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We manage these risks through regular operating and financing methods, including the use of derivative financial instruments when deemed appropriate. When we have derivative instruments, they are with major financial institutions and are not for speculative or trading purposes.

The following analysis presents the effect on our results of operations, cash flows, and financial position as if the hypothetical changes in market risk factors occurred at December 31, 2025. We analyzed only the potential impacts of our hypothetical assumptions. This analysis does not consider other possible effects that could impact our business.

Interest Rate Risk

At December 31, 2025, we had total long-term debt of $883 million. All of the long-term debt is at fixed rates except for $288 million outstanding under the revolving credit facility.

Holding all other variables constant, if the variable portion of the interest rates hypothetically increased 10%, the effect on our earnings and cash flow would have been additional interest expense of $1 million.

Holding all other variables constant, a hypothetical 100 basis point decrease in interest rates would have resulted in a change of $24 million in fair value of our debt at December 31, 2025.

Foreign Currency Risk

We sell to customers in foreign markets through our foreign subsidiaries, as well as through export sales from the United States. These transactions are often denominated in currencies other than the U.S. Dollar. Our primary currency exposures are the European Union Euro, British Pound Sterling, Japanese Yen, Chinese Renminbi, Indian Rupee, Singapore Dollar, Mexican Peso, Australian Dollar, and Canadian Dollar. We may enter into forward contracts as hedges to minimize the fluctuation of intercompany accounts receivable denominated in foreign currencies. At December 31, 2025, we had no outstanding forward contracts.

Raw Material Price Risk

We utilize a variety of raw materials in the manufacture of our products, including base oil, polyisobutylene, antioxidants, alcohols, solvents, detergents, friction modifiers, olefins, and copolymers. We may also enter into contracts which commit us to purchase some of our more critical raw materials based on anticipated demand. Our profitability is sensitive to changes in the quantities of raw materials we may need and the costs of those materials which may be caused by changes in supply, demand or other market conditions, over which we have little or no control. In addition, political and economic conditions in certain regions of the world in which we operate have caused, and may continue to cause, our demand for and the cost of our raw materials to fluctuate. War, armed hostilities, terrorist acts, civil unrest, inclement weather events, or other incidents may also cause a sudden, sharp, or prolonged change in our demand for and the cost of our raw materials. If we experience such increases in the cost of our raw materials, we may not be able to pass them along to our customers in the form of price increases for our products. The inability to do so would have a negative impact on our operating profit. In addition, if our demand for raw materials were to decline such that we would not have need for the quantities required to be purchased under commitment agreements, we could incur additional charges that would affect our profitability.

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ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

Report of Independent Registered Public Accounting Firm

To the Board of Directors and Shareholders of NewMarket Corporation

Opinions on the Financial Statements and Internal Control over Financial Reporting

We have audited the accompanying consolidated balance sheets of NewMarket Corporation and its subsidiaries (the “Company”) as of December 31, 2025 and 2024, and the related consolidated statements of income, of comprehensive income, of shareholders' equity and of cash flows for each of the three years in the period ended December 31, 2025, including the related notes (collectively referred to as the “consolidated financial statements”). We also have audited the Company's internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).