OLIN Corp (OLN) Business

Item 1.  BUSINESS

GENERAL

Olin Corporation (Olin, the Company, we or our) is a Virginia corporation, incorporated in 1892, having its principal executive offices in Clayton, MO. We are a leading vertically integrated global manufacturer and distributor of chemical products and a leading U.S. manufacturer of ammunition. Our operations are concentrated in three business segments: Chlor Alkali Products and Vinyls, Epoxy and Winchester. All of our business segments are capital-intensive manufacturing businesses. The Chlor Alkali Products and Vinyls segment manufactures and sells chlorine and caustic soda, ethylene dichloride (EDC) and vinyl chloride monomer (VCM), methyl chloride, methylene chloride, chloroform, carbon tetrachloride, perchloroethylene, hydrochloric acid, hydrogen, bleach products and potassium hydroxide, which represented 54% of 2025 sales. The Epoxy segment produces and sells a full range of epoxy materials and precursors, including aromatics (acetone and phenol), allyl chloride, epichlorohydrin, liquid epoxy resins, solid epoxy resins and formulated solutions products such as converted epoxy resins and additives, which represented 20% of 2025 sales. The Winchester segment produces and sells sporting ammunition, reloading components, small caliber military ammunition and components, industrial cartridges and clay targets, along with contracted U.S. military project revenue, which represented 26% of 2025 sales. See our discussion of our segment disclosures contained in Item 7—“Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

GOVERNANCE

We maintain a website at www.olin.com. Our reports on Form 10-K, Form 10-Q and Form 8-K, as well as amendments to those reports, are available free of charge on our website, as soon as reasonably practicable after we file the reports with the Securities and Exchange Commission (SEC). Also, a copy of our electronically filed materials can be obtained at www.sec.gov. Our Principles of Corporate Governance, Committee Charters and Code of Conduct are available on our website at www.olin.com in the Leadership & Governance Section under Governance Documents and Committees.

PRODUCTS, SERVICES AND STRATEGIES

Chlor Alkali Products and Vinyls

Products and Services

We have been involved in the chlor alkali industry for approximately 135 years and consider ourselves the leading global chlor alkali and derivatives producer. Chlorine, caustic soda and hydrogen are co-produced commercially by the electrolysis of salt at a fixed ratio of 1.0 ton of chlorine to 1.1 tons of caustic soda and 0.03 tons of hydrogen. The industry refers to this as an Electrochemical Unit or ECU.

Chlorine is used as a raw material in the production of thousands of products, including vinyls, urethanes, epoxy, water treatment chemicals and a variety of other organic and inorganic chemicals. A significant portion of chlorine production is consumed in the manufacturing of vinyls intermediates, EDC and VCM, both of which our Chlor Alkali Products and Vinyls segment produces. A large portion of our EDC production is utilized in the production of VCM, but we are also one of the largest global participants in merchant EDC sales. In addition to marketing Olin produced EDC, we also purchase EDC for re-sale on a global basis. EDC and VCM are precursors for polyvinyl chloride (PVC), a material used in applications such as vinyl siding, pipe, pipe fittings and automotive parts.

Our Chlor Alkali Products and Vinyls segment is one of the largest global marketers of caustic soda, including caustic soda produced by Olin, and globally produced material purchased by Olin for re-sale. The diversity of caustic soda sourcing allows us to cost effectively supply customers worldwide. Caustic soda has a wide variety of end-use applications, the largest of which includes water treatment, alumina, pulp and paper, urethanes, detergents and soaps and a variety of other organic and inorganic chemicals.

Our Chlor Alkali Products and Vinyls segment also includes our chlorinated organics business, which is a significant global producer of chlorinated organic products that include chloromethanes (methyl chloride, methylene chloride, chloroform and carbon tetrachloride) and chloroethanes (perchloroethylene). Our chlorinated organics business participates in both the solvent segment and the intermediate segment where Olin’s products are used as feedstocks for fluorocarbons, silicones and cellulosics.

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We also manufacture and sell other chlor alkali-related products, including hydrochloric acid, sodium hypochlorite (bleach) and potassium hydroxide. These products, along with chlorinated organics products and epoxy resins, generally consume chlorine as a raw material creating downstream applications that upgrade the value of the ECU. Our industry leadership in the production of chlorinated organics and epoxy resins, as well as other products, offers us multiple outlets for our captive chlorine.

Our products are delivered by pipeline, marine vessel, deep-water and coastal barge, railcar and truck. We own, operate, and lease a geographically dispersed terminal infrastructure at our production sites and other locations that expand our geographic coverage and enhance our service capabilities. At our largest integrated product sites, our deep-water access allows us to reach global markets.

Blue Water Alliance (BWA), our joint venture with Mitsui & Co., Ltd. (Mitsui), began operations during 2023. BWA is an independent global trader of ECU-based derivatives, focused on globally traded caustic soda and EDC. Olin holds 51% interest and exercises control in BWA, and the joint venture is consolidated in our financial statements with Mitsui’s 49% interest in BWA classified as noncontrolling interest. All intercompany accounts and transactions are eliminated in consolidation. On September 18, 2025, we announced a mutual decision with Mitsui to end our joint venture, BWA, by the end of 2025. This decision was made to evolve our EDC participation by emphasizing longer-term structural opportunities that enhance value and optionality. On November 11, 2025, Olin announced a commercial arrangement with Braskem, one of the largest petrochemical companies in the Americas and the leading producer of PVC in South America, for Olin to supply EDC to Braskem, aligning with Braskem's transformation of its chlor alkali and vinyl assets in Brazil.

Olin Corporation and Plug Power, Inc. launched a joint venture named Hidrogenii, LLC in 2024. This strategic partnership aims to leverage the strengths of both companies to advance hydrogen production and utilization. The joint venture began with the construction of a 15-ton-per-day hydrogen liquefaction plant in St. Gabriel, LA which commenced operations in the second quarter 2025. Hidrogenii is owned 50% by Plug Power LA JV, LLC, a wholly owned subsidiary of Plug Power, Inc. and 50% by Niloco Hydrogen Holdings LLC, a wholly owned subsidiary of Olin Corporation, which is accounted for using the equity method.

Our Chlor Alkali Products and Vinyls segment currently maintains a reliable supply of key raw materials. Electricity, salt, ethylene and methanol are the primary raw materials for our products. Electricity is the single largest raw material component in the production of Chlor Alkali Products and Vinyls products. Approximately 76% of our electricity is generated from natural gas or hydroelectric sources. We satisfy our electricity needs through a combination of market power, long-term contracts and the operation of our own power assets, which allow for cost differentiation at specific U.S. manufacturing sites. Approximately 73% of our salt requirements are met by internal supply. Ethylene is primarily supplied for the vinyls business under a long-term supply arrangement whereby we receive ethylene at integrated producer economics. Methanol is primarily sourced from large domestic and international producers. The high-volume nature of the chlor alkali industry places emphasis on cost management, and we believe that our scale, integration and raw material positions make us one of the low-cost producers in the industry.

The following table lists the principal products and services of our Chlor Alkali Products and Vinyls segment:

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* Includes low salt, high strength bleach manufacturing.

Strategies

Maximize Returns to the ECU. Leverage our diverse and flexible chlor alkali derivatives portfolio via our value-first operating model to continually preserve and enhance value from the entire ECU.

Continually Drive Down Costs. Our advantaged cost position is derived from low-cost energy, scale, integration, global distribution networks and a culture of continuous improvement. Maintaining a strong discipline in areas such as cost management, capital outlays, and asset maintenance is key to creating greater operating flexibility to maximize returns to the ECU. We continually execute on cost reduction initiatives through the optimization of our asset strategy, productivity, and deploying a performance-driven culture.

Optimize Our U.S. Leadership Position to Pursue Growth Opportunities. Fully utilize the portfolio of integrated derivatives to continually optimize value from the entire ECU to the highest value applications and provide organic expansion opportunities throughout the value chain.

Epoxy

Products and Services

The Epoxy business was one of the first major manufacturers of epoxy products and has continued to build on more than half a century of history through product innovation and technical excellence. We believe the Epoxy segment is one of the largest fully integrated global producers of epoxy resins, curing agents and intermediates. The Epoxy segment’s cost position benefits from integration into low-cost feedstocks (including chlorine, caustic soda, allylics and aromatics). The Epoxy segment produces and sells a full range of epoxy materials and precursors, including aromatics (acetone and phenol), allylics, such as allyl chloride (Allyl) and epichlorohydrin (EPI), resins such as liquid epoxy resins (LER) and solid epoxy resins (SER) and formulated solutions platform products such as converted epoxy resins (CER) and additives.

The Epoxy segment serves a diverse array of applications, many of which are focused on improving sustainability and lowering greenhouse gas emissions, including wind energy, electrical laminates, consumer goods and composites, as well as numerous applications in civil engineering and protective coatings. The Epoxy segment has important relationships with established customers, some of which span decades. The segment sells primarily in North America and Western Europe. The segment products are delivered primarily by marine vessel, deep-water and coastal barge, railcar and truck.

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Allyl is used not only as a feedstock in the production of EPI, but also as a chemical intermediate in multiple industries and applications, including water purification chemicals. EPI is primarily produced as a feedstock for use in the business’s epoxy resins and is also sold in the merchant market. LER is manufactured in liquid form and cures with the addition of a hardener into a three-dimensional thermoset solid material, offering a distinct combination of structural strength, adhesion, electrical insulation, thermal or chemical resistance and corrosion protection that is well-suited to coatings and composites applications. SER is processed further with bisphenol, which is produced internally to meet specific end-market applications. While LER and SER are sold externally, a significant portion of LER production is further converted through our formulated solutions platform into CER and other additive products where value-added modifications produce higher margin resins for specific customer applications.

The Epoxy segment’s principal raw materials are chlorine, caustic soda, cumene, propylene and aromatics, which consist of phenol and acetone. Our Epoxy segment maintains a reliable supply of certain key raw materials, such as cumene and propylene. The Epoxy segment’s production economics benefit from its integration into chlor alkali and aromatics which are key inputs in epoxy production. This fully integrated structure provides both access to low-cost materials and significant operational flexibility. The Epoxy segment operates an integrated aromatics production chain producing phenol and acetone for internal consumption and external sale. The Epoxy segment’s consumption of chlorine enables the Chlor Alkali Products and Vinyls segment to generate caustic soda production and sales. Chlorine and caustic soda used in our Epoxy segment are transferred at cost from the Chlor Alkali Products and Vinyls segment.

The following table lists the principal products and services of our Epoxy segment:

*    In December 2025, the Company made the decision to close our liquid epoxy resin manufacturing facility in Guarujá, Brazil. The closure is expected to occur during the first quarter 2026.

Strategies

Capitalize on Integrated Assets through Flexible Market Entry Points. The Epoxy segment is focused on maximizing value by capitalizing on our flexible market entry points across the value chain which extends our reach into a broad array of end markets.

Continually Drive Down Costs. The Epoxy segment continues to drive cost improvements through the entire supply chain to optimize our EPI and LER cost position in the Americas and Europe. We continually execute on cost reduction initiatives through the optimization of our asset strategy, productivity, and deploying a performance-driven culture.

Focus on Formulated Solutions Platforms. The Epoxy segment is focused on expanding our market participation in higher value add platform products to align with growing end-use markets.

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Winchester

Products and Services

In 2026, Winchester is in its 160th year of operation and its 96th year as part of Olin. Winchester is a premier developer and manufacturer of small caliber ammunition for sale to domestic and international retailers (commercial customers), law enforcement agencies and domestic and international militaries. We believe we are a leading U.S. producer of ammunition for recreational shooters, hunters, the U.S. Armed Forces and law enforcement agencies. Winchester also manufactures industrial products that have various applications in the construction industry and clay targets for recreational and competitive shooters.

On April 18, 2025, Olin acquired AMMO, Inc.’s small caliber ammunition manufacturing assets for total consideration of $55.8 million. The acquisition, which includes AMMO Inc.’s brass shellcase capabilities and its 185,000 square foot production facility located in Manitowoc, WI, is included in Olin’s Winchester segment.

On October 1, 2023, Olin acquired the assets of White Flyer Targets, LLC (White Flyer) from Reagent Diversified Holdings, Inc. (Reagent) for $63.5 million. White Flyer is North America’s preeminent leader in recreational trap, skeet, and sporting clay targets. White Flyer was combined with the Winchester Ammunition business.

On October 1, 2020, Winchester assumed full management and operational control of the Lake City Army Ammunition Plant (Lake City) in Independence, MO. The contract is for the production of small caliber military ammunition, including 5.56mm, 7.62mm, and .50 caliber rounds, as well as certain cartridges and casings. The contract also allows for the production of certain ammunition for commercial customers. The contract has an initial term of seven years and has been extended by the U.S. Army for three additional years. Our contracts with the U.S. military are subject to standard termination rights which generally include, without limitation, a right for the U.S. Government to terminate the contract for convenience.

Our legendary Winchester® product line includes all major gauges and calibers of shotgun shells, rimfire and centerfire ammunition for pistols and rifles, reloading components and industrial cartridges. We believe we are a leading U.S. supplier of small caliber commercial ammunition.

Winchester has strong relationships throughout the sales and distribution chain and strong ties to traditional dealers, distributors, and gun clubs. Winchester has also built its business with key high-volume mass merchants and specialty sporting goods and outdoor merchandise retailers. Winchester has consistently developed industry-leading ammunition, which is recognized in the industry for manufacturing excellence, design innovation and consumer value.

Winchester was awarded the following long-term contracts to support the U.S. military, its allies, and law enforcement:

•In 2021, the U.S. Army awarded Winchester a five-year contract to manufacture 5.56 mm, 7.62 mm and .50 caliber rifle ammunition under the third consecutive “Second Source” ammunition contract.

•In 2022, the U.S. Army awarded Winchester a five-year contract to manufacture .38 caliber, .45 caliber and 9mm handgun ammunition, maintaining Winchester’s longstanding position as the leading supplier of pistol ammunition to the U.S. military.

•In 2023, the U.S. Army awarded Winchester contracts to manufacture, test and deliver five million rounds of 6.8mm ammunition and develop, and manufacture multiple high-performance cartridges at Lake City, including nearly two million rounds of .50 Caliber Saboted Light Armor Penetrator ammunition.

•In 2024, after completing a contract to design a 6.8mm Next Generation Squad Weapon (NGSW) ammunition manufacturing facility, the U.S. Army awarded Winchester the contract to construct the facility at Lake City, and in 2025, awarded Winchester the initial contract to purchase, install and test all equipment for the newly constructed facility. In 2024, U.S. Special Operations Command awarded Winchester and three other awardees contracts for numerous types of ammunition, and Canada’s Royal Canadian Mounted Police awarded Winchester a three-year contract for 9mm duty ammunition.

•In 2025, Winchester signed a four-year contract from Canadian Border Services and Canadian Corrections for 9mm duty ammunition. In 2025, Winchester also signed a multi-year contract with GTDS Europe B.V. to support the Netherlands with 5.56mm and 7.62mm ammunition and signed a multi-year agreement with FN, the defense division of FN Browning Group, to support the Belgium Ministry of Defense with 5.56mm & 7.62mm ammunition.

Winchester’s new ammunition products continue to receive awards from major industry publications and organizations, with recent awards including American Rifleman magazine’s Golden Bullseye Award as “Ammunition Product of the Year” in 2025 and American Hunter magazine’s Golden Bullseye award as “Ammunition Product of the Year” in 2025. The National Wild Turkey Federation chose Winchester to receive its 2024 Corporate Achievement Award in recognition of Winchester’s support of wild turkey conservation and the preservation of hunting heritage.

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Winchester purchases raw materials such as copper-based strip and ammunition cartridge case cups and lead from vendors, pursuant to multi-year contracts, based on a conversion charge or premium. These conversion charges or premiums are in addition to the market prices for metal as posted on exchanges such as the Commodity Exchange, or COMEX, and London Metals Exchange, or LME. Winchester’s other main raw material is propellant, which is purchased predominantly from one of the U.S.’s largest propellant suppliers.

The following table lists the principal products and services of our Winchester segment:

*    Government-owned, contractor-operated (GOCO) facility

Strategies

Maximize Existing Strengths. Winchester will increase our value by strengthening our leadership position in small caliber ammunition through all of the customer segments that we serve. With one of the world’s largest small caliber ammunition manufacturing footprints, we will leverage employee engagement, engineering, and process excellence across our production sites while capitalizing on Olin’s deep chemical expertise to expand our defense participation through synergies between ammunition and chemicals. We will drive further global brand awareness as ‘The American Legend’ — a longstanding highly-valued brand built on integrity, hard work, and customer loyalty.

Innovative Solutions. Winchester will continue building on our strong reputation as an industry innovator with a long record of meeting the needs of recreational shooters, first responders, and the modern warfighter. We will build value by developing market driven products, delivering engineered solutions for our customers and increasing our integration across the ammunition value chain.

Continually Drive Down Costs. Winchester promotes a culture of continuous improvement with a “Be Better Today” mindset. We deploy our world-class assets with disciplined approaches to productivity, reliability and modernization.

INTERNATIONAL OPERATIONS

Olin has an international presence, including the geographic regions of Europe, Asia Pacific and Latin America. Approximately 32% of Olin’s 2025 sales were generated outside of the U.S., including 31% of our Chlor Alkali Products and Vinyls 2025 segment sales, 59% of our Epoxy 2025 segment sales and 13% of our Winchester 2025 segment sales. See Note 19, “Segment Information,” of the notes to consolidated financial statements contained within Item 8—“Financial Statements and Supplementary Data,” for geographic segment data. We are incorporating our segment information from that Note into this section of our Form 10-K.

CUSTOMERS AND DISTRIBUTION

Products we sell to industrial or commercial users or distributors for use in the production of other products constitute a major part of our total sales. We sell some of our products, such as epoxy resins, caustic soda and sporting ammunition, to a large number of users or distributors, while we sell other products, such as chlorine and chlorinated organics, in substantial

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quantities to a relatively small number of industrial users. During 2025, no single customer accounted for more than 10% of sales.

We market most of our products and services primarily through our sales force and sell directly to various industrial customers, mass merchants, retailers, wholesalers, gun clubs, other distributors and the U.S. Government and its prime contractors.

Sales to all U.S. government agencies and sales under U.S. government contracting activities in total accounted for approximately 13% of sales in 2025. Because we engage in some government contracting activities and make sales to the U.S. government, we are subject to extensive and complex U.S. government procurement laws and regulations. These laws and regulations provide for ongoing government audits and reviews of contract procurement, performance and administration. Failure to comply, even inadvertently, with these laws and regulations and with laws governing the export of munitions and other controlled products and commodities could subject us or one or more of our businesses to civil and criminal penalties, and under certain circumstances, suspension and debarment from future government contracts and the exporting of products for a specified period of time.

BACKLOG

The total amount of estimated backlog was approximately $1,331 million and $1,426 million as of January 31, 2026 and 2025, respectively. The backlog orders are associated with contractual orders in our Winchester business. Backlogs in our other businesses are not significant. Backlog is comprised of all open customer orders which have been received, but not yet shipped. The backlog was estimated based on expected volume to be shipped from firm contractual orders, which are subject to customary terms and conditions, including cancellation and modification provisions. Approximately 81% of the contracted backlog as of January 31, 2026, is expected to be fulfilled during 2026, with the remainder expected to be fulfilled during 2027.

COMPETITION

We are in active competition with businesses producing or distributing the same or similar products, as well as, in some instances, with businesses producing or distributing different products designed for the same uses.

Chlor alkali manufacturers in North America, with approximately 16 million tons of chlorine and 17 million tons of caustic soda capacity, account for approximately 14% of worldwide chlor alkali production capacity. In 2025, we have the largest chlor alkali capacity in North America and globally. While the technologies to manufacture and transport chlorine and caustic soda are widely available, the production facilities require large capital investments and are subject to significant regulatory and permitting requirements. There is a global market for caustic soda, which attracts imports and allows exports depending on market conditions. This industry includes large, diversified producers in North America and abroad, including multiple producers located in Europe, China and India. Other large chlor alkali producers in North America include OxyChem, a former subsidiary of The Occidental Petroleum Corporation, which sold OxyChem to Berkshire Hathaway in January 2026, Westlake Chemical Corporation (Westlake), Formosa USA, and Shintech Incorporated (Shintech), a subsidiary of Shin-Etsu Chemical Co., Ltd.

We are a major global fully integrated epoxy producer, with access to key low-cost feedstocks and a cost advantaged infrastructure. The markets in which our Epoxy segment operates are highly competitive and are dependent on significant capital investment, the development of proprietary technology and the maintenance of product research and development. Among our competitors are Huntsman Corporation, Westlake, Kukdo Chemical Co. Ltd. and Kumho P&B Chemicals, as well as multiple other producers located in Asia. We remain exposed to competition from low-priced imports across our full range of epoxy materials and precursors.

We believe our Winchester business is one of the largest global manufacturers of commercial small caliber ammunition. Our Winchester business and The Kinetic Group (purchased from Vista Outdoor Inc. in November 2024 by Czechoslovak Group) are among the largest commercial ammunition manufacturers in the U.S. The ammunition industry is highly competitive with Olin, The Kinetic Group and numerous smaller domestic manufacturers and foreign producers competing for sales to the commercial ammunition customers. Many factors influence our ability to compete successfully, including price, delivery, service, performance, product innovation and product recognition and quality, depending on the product involved.

HUMAN CAPITAL

Overview

At Olin, our engaged workforce is the foundation of our success. Olin employees drive the actions necessary for our Company to successfully execute our business strategies and effectively deliver for our shareholders. Each year, our employees set goals that seek to align with the Company’s strategic priorities and then work to demonstrate their creativity, dedication and expertise to achieve those goals every day. Our Olin values, programs and processes support a culture of collaboration, engagement and elevated performance, reflecting our “all-in” culture. Olin’s resilience as a company is a product of a

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workforce that brings their unique skills and perspectives, and a shared commitment to excellence to their jobs every day and propels our Company forward. Our employees embody our “All In For Olin” culture.

Employee engagement is the catalyst that propels our Company. To enhance the culture of purposeful engagement, Olin has created a platform around our “All In For Olin” values in an effort to create work environments for our global workforce that are inclusive, supportive, and empowering while encouraging and incentivizing the highest level of performance and accountability to deliver the results necessary to achieve our strategic goals. We support our global workforce by providing competitive benefits and compensation, robust recognition and rewards, a variety of workplace flexibility options, support and resources for community engagement and volunteerism, and professional development programs and opportunities, all of which, we believe, constitute a strong Olin employee value proposition. In 2025, Olin employees continued to demonstrate their commitment to the communities where our plants and offices are located by volunteering more than 56,000 hours to multiple organizations and causes. To further support our employees who may be impacted by natural disasters, we established the Olin Employee Disaster Relief Fund to allow Olin employees to contribute funds to help fellow employees in need. Olin matches these contributions up to $250,000 annually. We commit to providing our employees with a safe and supportive environment and to maintaining a steadfast commitment to safely producing and distributing our products, which is fundamental to achieving our goals. Our global workforce is committed to the We Care and Me Principles which focus on each individual’s responsibility for their own safety and that of others, on leading by example, on reinforcing positive behaviors and on elevating concerns.

Vital to Olin’s achievement of our organizational goals and objectives is our ability to attract and retain a talented workforce. As a company, we are committed to providing meaningful opportunities and fulfillment for employees, providing robust communication and varied opportunities for connection, and fostering an environment of trust. Additionally, we have committed significant effort to cultivate a total rewards package that includes flexible benefits and compensation structures that seek to ensure our market competitiveness and support a pay-for-performance philosophy. Olin senior management provides oversight of these programs, while our human resources organization manages and administers them so that our total rewards programs remain market competitive. This includes conducting periodic compensation benchmarking, implementing health and other employee benefit programs and reviewing certain employee post-retirement benefits and accessibility of employee assistance programs. We have established both salaried and hourly employee structures to adequately compensate employees, and have implemented monetary rewards and recognition programs as additional mechanisms for supervisors to reward exceptional performance. Our recognition and rewards program gives people leaders across our organization a platform to recognize employees’ contributions throughout the year, and in 2025 our leaders provided more than 4,500 recognition awards. We also provide a mechanism for employees to provide non-monetary peer-to-peer recognition in the form of Impressions, which totaled more than 9,000 in 2025. Separately, our Board of Directors maintains a Compensation Committee that sets policies, develops and monitors strategies, and administers the programs used to compensate our Chief Executive Officer and other senior executives.

Olin is committed to maintaining work environments free from all forms of discrimination and harassment and where all employees feel supported both professionally and personally. We believe the insights from our workforce, with their unique skills, backgrounds and experiences, will lead to future innovations that reduce costs, reduce our environmental footprint, improve our ability to serve the world and keep our employees healthy and safe. We encourage our employees to be creative and participate in the dialogue across the Company to help solve problems and develop innovative solutions that lead to lasting, positive impacts for our customers, employees, communities, and shareholders. Our Voice of the Employee mechanism facilitates sharing insights across multiple sites, while our Olin Employee Networks focus on site-specific activities designed to foster and encourage connection and engagement. Our U.S. college recruiting program is a key component of our talent pipeline. Additionally, Olin employees are our best recruiters with 44% of our hires in 2025 attributable to employee referrals.

Training and Development

We also invest in the continued professional development of our workforce. Olin provides a wide range of employee development programs, including assignment-based opportunities, job shadowing, mentoring, foundational programs for new Olin employees, and leadership programs for rising leaders. A tiered leadership development program equips our critical talent with tools to support their continued growth in, and aspirations toward, leadership roles. These programs help our employees improve, grow, and reinforce our values. Our learning platform provides a variety of educational opportunities that support career and professional development for our employees, including undergraduate and graduate tuition assistance for eligible employees up to a maximum of $10,000 per year. We regularly review talent development and succession plans to identify and develop a pipeline of talent to maintain and continuously improve business operations. We make purposeful moves to accelerate the development of high potential employees. Our performance management process encourages ongoing feedback throughout the year and includes annual year-end reviews and regular development discussions.

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Workforce

As of December 31, 2025, we had 7,849 employees broken out as follows:

(1)     Various labor unions represent a significant number of our hourly-paid employees for collective bargaining purposes. In the U.S., bargaining unit employees comprise 36% of the total workforce. In 2026, we have no labor agreements that are due to expire in Canada, and three labor agreements expiring in the U.S., including our East Alton, IL, facility (523 employees) and our Lake City facility in Independence, MO (1,358 employees), representing approximately 24% of our global workforce.

(1)     Includes 1,845 employees from Chlor Alkali Products and Vinyls, 1,001 employees from Epoxy and 523 employees for common services within Chemicals.

(2)     Includes 1,869 employees at Lake City in Independence, MO, which is a GOCO facility.

RESEARCH ACTIVITIES: PATENTS

Our research activities are conducted on a product-group basis at a number of facilities. Company-sponsored research expenditures were $19.3 million, $18.4 million and $20.0 million in 2025, 2024 and 2023, respectively.

We own or license a number of patents, patent applications and trade secrets covering our products and processes. We believe that, in the aggregate, the rights under our patents and licenses are important to our operations, but we do not consider any individual patent, license or group of patents and licenses related to a specific process or product to be of material importance to our total business.

SEASONALITY

Our sales are affected by economic downturns and the seasonality of several industries we serve, including building and construction, coatings, oil and gas, infrastructure, electronics, automotive, water treatment, refrigerants and ammunition. The seasonality of the ammunition business is typically driven by the U.S. fall hunting season. Our chlor alkali businesses generally experience their highest level of activity during the spring and summer months, particularly when construction, refrigerants, coatings, infrastructure and water treatment activities are higher. Our Epoxy segment also serves a number of applications which experience their highest level of activity during the spring and summer months, particularly civil engineering and protective coatings and other construction materials, including composites and flooring.

RAW MATERIALS

Basic raw materials are processed through an integrated manufacturing process to produce a number of products that are sold at various points throughout the process. We purchase a portion of our raw material requirements and also utilize internal resources and finished goods as raw materials for downstream products. We believe we have reliable sources of supply for our raw materials under normal market conditions. However, we cannot predict the likelihood or impact of any future raw material shortages. We provide additional information with respect to specific raw materials in the tables set forth under “Products, Services and Strategies.”

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ENVIRONMENTAL AND TOXIC SUBSTANCES CONTROLS

As is common in our industry, we are subject to environmental laws and regulations related to the use, storage, handling, generation, transportation, emission, discharge, disposal and remediation of, and exposure to, hazardous and non-hazardous substances and wastes in all of the countries in which we do business.

The establishment and implementation of national, state or provincial and local standards to regulate air, water and land quality affect substantially all of our manufacturing locations around the world. Laws providing for regulation of the manufacture, transportation, use and disposal of hazardous and toxic substances, and remediation of contaminated sites have imposed additional regulatory requirements on industry, particularly the chemicals industry. In addition, implementation of environmental laws has required and will continue to require new capital expenditures and will increase operating costs.

We are a party to various government and private environmental actions associated with former waste disposal sites and past manufacturing facilities. Charges to income for investigatory and remedial efforts were $25.5 million, $30.2 million and $30.1 million for the years ended December 31, 2025, 2024 and 2023, respectively. These charges may be material to operating results in future years. These charges do not include insurance recoveries for costs incurred and expensed in prior periods.

See our discussion on environmental matters contained within Note 20, “Environmental,” of the notes to consolidated financial statements within Item 8—“Financial Statements and Supplementary Data,” and under the heading “Environmental Matters,” within Item 7—“Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

CORPORATE RESPONSIBILITY

At Olin, we are committed to corporate responsibility to ensure the long-term success of our business, our collective global society and the well-being of our environment. We focus our corporate responsibility efforts on the areas of: (1) environment, health, safety and security stewardship, (2) sustainability and governance and (3) product stewardship. We value collaboration and commit to working with other organizations to encourage collective action for improving corporate responsibility. Additional information related to our corporate responsibility initiatives, practices, activities, goals and related information, as well as future updates, can be found in the Corporate Responsibility section of our website at www.olin.com, including our Sustainability Report under the section Sustainability Success. Our progress against our sustainability targets is included therein. The contents of our website referenced in this section are not, and should not be considered to be, part of this Report.

Environment, Health, Safety and Security Stewardship

Olin is strongly committed to excellence in protecting the environment, health, safety and security of our employees and those who live and work around our plants. Our operations worldwide comply with all local requirements and implement additional standards as required to protect the environment, health, safety and security of our operations. We use our management system to drive continuous improvement and achieve excellence in environmental, health, safety, process safety and security performance. Our safety, health and environmental strategy and goals are designed to sustain our drive to zero incidents. Relentlessly and responsibly, we constantly emphasize the importance of monitoring the safety, security and environmental impact of our facilities and processes. Through our daily vigilance, Olin strives to continue to be recognized as one of the industry’s best performers.

At Olin, we believe our purpose is to deliver essential materials and solutions that enhance and protect lives. By consistently integrating corporate values into the fabric of the organization, we believe we can create a strong, cohesive culture that drives success and employee engagement. Olin’s corporate values are:

•We safely and reliably deliver essential materials

•We act with integrity, always doing what is right

•We empower our employees to take ownership in everything we do

•We create value for our customers, shareholders, employees, and communities

These values are also reflected in our Environment, Health, Safety and Security (EHS&S) policy and practice. Olin leadership visibly performs and guides the organization to conduct business in a manner that protects and increasingly benefits our employees, business partners and the communities in which we live. All employees have responsibilities within our management systems necessary to sustain our drive to zero incidents.

Sustainability and Governance

We strongly believe in meeting the needs of the present without compromising the needs of future generations. We recognize our Company’s impact on our natural resources and our responsibility to stewardship of people and the planet. This means striving for a company culture responsible to the ongoing sustainability ideals of our employees and shareholders.

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At Olin, we integrate sustainability into everything we do as a responsible corporate citizen. We value and respect our people, the communities in which we operate, our customers and the environment. We commit to making a contribution to protecting the world and its future condition through the safety and efficiency of our business practices - from supply to manufacturing to delivery and ultimately the end-use of our products. Executing on our sustainability strategy, we believe Olin will increase value for our investors, employees, and customers by enhancing our operating model through focused sustainability actions. These actions include:

•Protecting our employees and communities through our industry-leading occupational and process safety programs

•Proudly strengthening United States defense, international defense, law enforcement, and conservation through our Winchester ammunition brand

•Significantly reducing our environmental impact by taking concrete steps through technology and commercial innovation to lower our carbon footprint, net water usage, and resource consumption

•Developing and enabling sustainable solutions within the value chain through our product and service offerings

•Consistently upholding our values and governance standards as we amplify our culture of high performance and engagement

We believe Olin’s industry leadership, focused sustainability actions, and our engaged workforce will create a positive, long-lasting impact on our communities and the environment.

Product Responsibility

We take pride in safely distributing and handling our products and enabling our customers to do the same. Our product stewardship and quality practices are aligned with our core values and other globally recognized standards. We apply these standards to our chemical business segments and relevant subsidiaries to ensure compliance with applicable global regulations, evaluation, continuous improvement and transparency of relevant production and product or formulation information. Additionally, Winchester ammunition is designed and manufactured in accordance with the voluntary industry standards published by the Sporting Arms and Ammunition Manufacturers’ Institute. Our goal is to meet or exceed guidelines in every instance. Olin leadership demonstrates its commitment to these standards through active participation and communication concerning product safety, within our organization and to external stakeholders. We are deeply committed to ammunition education and advocate strongly for owners and participants to take the necessary steps to be trained and educated when handling, storing or using a firearm for recreational purposes, both for experienced and novice participants. Winchester dedicates an increasing share of its online content to safety education materials for all to responsibly and confidently own and use Winchester products.