Ecovyst Inc. (ECVT) Business

ITEM 1.    BUSINESS.

Ecovyst Inc. (“Ecovyst” or the “Company”), formerly PQ Group Holdings Inc., was incorporated in Delaware on August 7, 2015. We trace our roots to the late 1800s with our first sulfuric acid plant and the beginning of our oldest customer relationship.

Our common stock is listed on the New York Stock Exchange under the stock ticker “ECVT”. Unless the context otherwise indicates, the terms “Ecovyst Inc.,” “we,” “us,” “our,” or the “Company” mean Ecovyst Inc. and our subsidiaries.

Effective on December 31, 2025, we completed the sale of our Advanced Materials & Catalysts segment, which includes our investment in affiliated companies, Zeolyst International and Zeolyst C.V. (collectively, the “Zeolyst Joint Venture”) to Technip Energies N.V. for a purchase price of $556.0 million, subject to certain adjustments set forth in the agreement. We used $465.0 million of the net cash proceeds to partially repay the Senior Secured Term Loan Facility due June 2031. The results of operations, financial condition and cash flows for the Advanced Materials & Catalysts business are presented herein as discontinued operations. Refer to Note 4 to our consolidated financial statements for additional information.

Our Company

We are a leading integrated provider of virgin and regenerated sulfuric acid products and services. We believe that our business contributes to improving the sustainability of the environment.

We are a leader in our business, holding what we estimate to be a number one or number two supply share position for products and services that generated more than 95% of our 2025 sales. We believe that our footprint and efficient network of strategically located manufacturing and regeneration facilities provide us with a strong competitive advantage in serving our customers.

Our products and services typically represent a small portion of our customers’ overall end-product costs, yet are critical to their processes. With our long history of customer partnerships and our reputation for providing reliable, quality products and services, we believe we deliver significant value to our customers, as demonstrated by our profit margins.

We are diversified by business application and end use. In 2025, the majority of our sales were for applications that have historically had relatively predictable, consistent demand patterns associated with consumption and industrial processes.

As a result of our competitive strengths, we have generally maintained stable earnings and margins over time and through changing macro economic cycles.

In 2025, we served customers across many end uses and, as of December 31, 2025, operated out of nine strategically located manufacturing facilities.

Our Strategy

We intend to capitalize on our strong business fundamentals and long-term customer partnerships to grow sales, maintain high margins, deploy capital efficiently and generate consistent free cash flow in order to create stockholder value. We believe that our long history of operational excellence and proven reliability, longstanding customer relationships, a network of strategically located manufacturing facilities and consistent business execution developed from our industry experience positions us well to execute our business strategy.

Our Industry

The products and services that we provide to our customers are often high value-add, even when they represent a small portion of our customers’ overall end product costs, and we believe we can continue to be successful by providing customers with quality products and reliable service. We believe many of the end uses that we serve are generally more resilient to economic cycles, minimizing extreme fluctuations in demand. We believe our customers value our geographic proximity to their operations and our plant network provides redundancy in capacity to serve their needs.

We believe the combination of attractive operating margins and generally predictable maintenance capital expenditure requirements improves our ability to generate attractive cash flows.

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Our Product End Uses

The table below summarizes our key end use applications and products, as well as the significant growth drivers in those applications.

The table below summarizes sales for the years ended December 31, 2025, 2024 and 2023, respectively:

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Competitive Business Strengths

Favorable Secular Growth Trends Across the Portfolio

We focus on serving end use applications where we believe our competencies can create value and where significant growth potential exists. Our products and services address our customers’ needs, which are typically driven by regulatory requirements or consumer preferences. We design our products and services to address evolving customer needs.

We believe that stringent fuel efficiency standards that spur the use of high compression engines requiring higher-octane gasoline and continued stringent regulatory requirements for gasoline will continue to encourage strong alkylate production at our refining customers. Our business is well positioned to benefit from any related growth in demand for alkylate.

We also believe we have opportunities to displace other less environmentally friendly materials for industrial and consumer good applications. We are the largest North American recycler of sulfuric acid and one of the largest consumers of refinery sulfur by-products, enabling them to be converted for use in other applications.

Leading Supply Positions

We believe that we maintain a leading supply position, holding what we estimate to be the number one or two supply share position in 2025 for products that generated more than 95% of our sales. We believe that our efficient network of strategically located, owned manufacturing facilities provides us with a strong competitive advantage in serving our customers, and that it would be costly for our competitors to replicate our network.

Long-Term, High Quality Customer Relationships

We collaborate with leading multinational companies. Our customers include large industrial companies. We have long-term relationships with our top ten customers, based on 2025 sales, that average more than 50 years. In addition, our customer base is diversified, with our top ten customers in 2025 representing approximately 61% of our sales for the year ended December 31, 2025, of which one customer had more than 10% of our total sales. This customer represented 12% or $89 million of our sales during this period.

Secured Contractual Pass-through of Raw Material Costs Support Stable Margins

We have been able to mitigate the impact of raw material or energy price volatility using a variety of mechanisms, including raw material cost pass-through mechanisms in our sales contracts and other adjustment provisions. Most of our contracts feature minimum volume protection and/or quarterly price adjustments for items such as commodity inputs, labor, the Chemical Engineering Plant Cost Index and natural gas. In 2025, approximately 90% of our sales occurred under contracts that included some form of raw material pass-through clause. These price adjustments generally reflect our actual cost structure in producing sulfuric acid and tend to provide us with some protection against volatility in labor, fixed costs and raw material pricing. Freight expenses are generally passed through directly to customers.

Our products are produced from readily available raw materials. We also use natural gas in our manufacturing process where our North American facilities have benefited from the plentiful supplies of shale gas. In addition, we have long-term contracts and relationships with many of our key raw material suppliers.

Long-Term Customer Contracts Enhance Sales Predictability and Stability

We partner with many of our customers under long-term contract agreements, 100% requirement arrangements. Approximately 40% of our production capacity serves customers with staggered multi-year commitment contracts with the potential for value pricing resets and cost pass-through for our regeneration services product line that enhance sales and margin predictability and stability. Excluding contracts with automatic evergreen provisions, approximately 40% of our sulfuric acid volume for the year ended December 31, 2025 was under contracts expiring at the end of 2026 or beyond.

Strategic and Differentiated Manufacturing Know-how and Supply Chain Network

Ecoservices’ predecessor company, Stauffer Chemical, was a leader in pioneering the current sulfuric acid regeneration technology in the 1940s. Since then, we have leveraged our process technology expertise and ability to deliver our products by barge, rail, truck and pipeline to become the largest sulfuric acid regenerator in North America and a leading North American producer of high-quality virgin sulfuric acid. In May 2025, we expanded our virgin and regenerated sulfuric acid services capacity through our purchase of the sulfuric acid production assets of Cornerstone

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Chemical Company LLC (“Cornerstone”) located in Waggaman, Louisiana. We also apply our capabilities in thermal decomposition to provide treatment services for hazardous/non-hazardous wastes, and to activate third party catalysts with our patented Chem 32, LLC (“Chem32”) technology.

Stable Margins and Cash Flow Generation Across Changing Macroeconomic Cycles

The secular trends supporting our businesses have allowed us to maintain stable margins while continuing to grow and perform throughout challenging macroeconomic environments. We believe that the stability of our margins and cash flows is also aided by long-term sales contracts and material cost pass-through provisions. Our ability to enter into favorable contracts and terms with customers is driven by our long history of collaborative relationships and track record of providing value-added products and services. We believe that our value-added products and services have proven to be critical to our customers’ operations and products and typically represent only a small portion of our customers’ overall end-product costs.

We believe our strong commercial contact structure enables our businesses to generate strong operating cash flow. In addition, our cash flow generation has been driven, in part, by lower debt levels, our disciplined capital investment practices, as well as tax attributes that provide us with cash flow benefits. As of December 31, 2025, we had $142.7 million of tax-deductible intangibles and goodwill, which provides us with cash tax savings as we generate taxable income.

Our Business

We are a leading integrated provider of virgin and regenerated sulfuric acid products and services. We believe that our business contributes to improving the sustainability of the environment.

The table below summarizes certain information for the year ended December 31, 2025:

Refer to “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Key Performance Indicators” for discussion of our use of non-GAAP financial measures and reconciliations.

We are a leading provider of sulfuric acid recycling (“regeneration services”) and end-to-end logistics to North American refineries to support the production of alkylate, a high value gasoline blending component required for meeting gasoline specifications and producing premium grade fuel. We are also a leading North American producer of on-purpose virgin sulfuric acid for water treatment, mining, and industrial applications (“virgin sulfuric acid”). We provide treatment services for hazardous/non-hazardous industrial wastes (“treatment services”) and we are also a leader in ex-situ sulfiding and pre-activation for hydro-processing catalysts, which are used in the production of traditional and sustainable fuels. By providing regeneration services, as well as purchasing by-product sulfur from customers for use in manufacturing virgin sulfuric acid, we believe that we provide our refining customers with a complete solution for their sulfuric acid needs.

We believe recent trends for increased alkylate production are being driven by the following factors: rising demand for premium gasoline used in smaller, more efficient turbocharged engines, which requires an alkylate content of approximately 40%-45%, as compared to the approximately 12%-13% alkylate content in regular gasoline; the need for more alkylate to meet the minimum octane ratings in regular gasoline following the continued significant share growth of shale oil refining in the U.S.; the full implementation of Tier 3 gasoline sulfur standards in the United States enacted in 2020, which requires the blending of additional low sulfur, high octane gasoline components such as alkylate; and rising gasoline exports, which gasoline generally contains no ethanol and generally requires more alkylate to replace the missing ethanol in order to meet minimum octane requirements in the destination countries.

Our business is mostly regional due to shipping costs and our customer integration requirements. Our network of facilities is concentrated in the Gulf Coast and the state of California, where approximately 64% of the United States refining capacity is located. We believe that the strategic locations of our plants in these key refining regions contribute to our efficient supply chain networks with our customers, including in some cases captive pipelines connecting us to our refinery customers. Additionally, product can be shipped to our customers by barge, rail and truck.

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Primary Product Groups

Our regeneration services product group serves a critical need for refining customers. Sulfuric acid serves as a catalyst in the alkylation production process. The resulting spent sulfuric acid needs to be regenerated or recycled, which is no longer a core competency of most refiners. Because storage space for fresh and spent sulfuric acid is typically limited, and the cost to refineries of interruption to their alkylation units would be significant, refineries seek to have a continuous and reliable source of supply for sulfuric acid regeneration services.

Our end-to-end regeneration services offering takes the spent acid from the refinery, through our network of plants and transportation systems, and recycles the sulfuric acid into high strength fresh sulfuric acid for reuse in the alkylation process. Because of the number and strategic locations of our plants, and the breadth of our transportation logistics, we believe we bring the highest reliability and flexibility to our refining customers, allowing them to focus on their core competency by optimizing their alkylation capacity.

Virgin sulfuric acid is created either through incinerating sulfur in furnaces, or as a by-product of other industrial processes, primarily the smelting of copper and other base metals. Our sulfur-derived, high quality virgin sulfuric acid products supply a diverse set of end uses. Sulfur derived acid is generally considered to be of higher purity and quality than smelter-produced acid and, as a result, smelter-produced acid is not suitable for some industrial users including several of our larger customers who require higher quality and differentiated sulfuric acid products, such as super-saturated sulfuric acid (oleum). Virgin sulfuric acid is produced at all of our facilities utilizing the same production equipment as our regeneration services product group.

Treatment services is a niche offering providing a thermal destruction solution for the management of bulk quantities of hazardous and non-hazardous by-products, co-products and waste materials. We specialize in handling sulfur-bearing materials, acidic materials, high-temperature molten materials and other hard to handle liquids. Our process provides a beneficial reuse alternative to traditional disposal by capturing the energy value and sulfur content of these materials, supplementing our processes, and offsetting the use of virgin raw materials.

Our catalyst activation offering, also known as Chem32, is a leader in ex-situ sulfiding and pre-activation for hydro-processing catalysts, which are used in the production of traditional and sustainable fuels. Chem32 sulfides and activates catalysts and absorbents which are used in refining, petrochemical and environmental processes, using its proprietary fixed-bed sulfiding technology.

Competition

Given our strategic presence on the Gulf Coast and in California, and our relationships with leading refineries, we estimate that our regenerated sulfuric acid supply share is substantially larger than our closest competitor. We compete in the North American refining services industry with competitors such as Chemtrade and Nexpera, formerly the sulfuric acid business of Veolia. We compete on the basis of price, reliability, and responsiveness to changes in customer demand, which is a function of scale, proximity to customer locations and operational expertise. We believe that we benefit from industry economics that favor incumbent producers because the capital cost and regulatory challenges to expand existing capacity are typically significantly less than to build a new plant. In addition, existing robust supply chains, including captive pipeline connections and other transportation logistics, add to the competitive advantages available to incumbent producers. As a result, we believe that our integrated and strategically located network of facilities and end-to-end logistics assets in the United States provide us with a significant competitive advantage and would be costly for our competitors to replicate.

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Manufacturing

We provide regenerated sulfuric acid and produce virgin sulfuric acid through our furnace operations. Regenerated sulfuric acid is produced by thermally decomposing the spent acid in our furnace into a clean gas stream, which is converted into sulfuric acid. Virgin sulfuric acid is produced by burning sulfur and certain sulfur-rich components at high temperatures within a furnace to create a gas stream. The chart below summarizes the manufacturing platform for our business.

Manufacturing Platform

Intellectual Property

We evaluate how best to use patents, trademarks, copyrights, trade secrets and other available intellectual property protections on a case-by-case basis. Patents extend for varying periods in accordance with the date of patent application filing and the legal life of such patents. The protection afforded depends upon the type of subject matter covered by the patent and the scope of the claims of the patent.

Patent protection may be available for unique applications and production processes. Moreover, we monitor our competitors’ products and, if circumstances were to dictate that we do so, we would vigorously challenge the actions of others that conflict with our patents, trademarks and other intellectual property rights. We maintain appropriate information security policies and procedures reasonably designed to ensure the safeguarding of confidential information including, where appropriate, data encryption, access controls and employee awareness training.

We own or have rights to a number of patents relating to our products and processes. As of December 31, 2025, we owned 5 patented inventions in the United States. As of December 31, 2025, we also had 68 trademark registrations worldwide, including 4 U.S. trademark registrations. We also have 6 pending trademark applications, which include applications in the United States and worldwide. In addition to our registered and applied-for intellectual property portfolio, we also claim ownership of certain trade secrets and proprietary know-how developed by and used in our business.

Seasonality

Our regeneration services product group typically experiences seasonal fluctuations as a result of higher demand for gasoline products in the summer and lower demand in the winter months. These demand fluctuations result in higher sales and working capital requirements in the second and third quarters.

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Sustainability Overview

Sustainability is intertwined with our daily business and is reinforced through our strategy and values. We strive to create sustainable products that are safe for the environment, and to reduce waste and increase efficiencies for our customers and stakeholders. We believe that our products contribute to lower emissions and cleaner air. We are committed to creating environmentally responsible products that we believe make a difference in people’s daily lives and for our planet.

While offering products and services that help our customers to advance their own sustainability goals, we also work to advance our commitment to maintain sound environmental, social and governance practices, policies and procedures. For example, we:

•Were awarded a 2025 Gold Sustainability Rating from EcoVadis, a third-party sustainability evaluation company. The Gold Medal rating from EcoVadis placed us among the top 5% (95th percentile) of all companies assessed by EcoVadis over the prior twelve-month period;

•Maintained an executive level position of Vice President – Environment and Sustainability that reports directly to our Chief Executive Officer;

•Under the executive leadership, instituted additional health, safety and process safety programs, as well as continued our company-wide employee health and wellness program that covers both physical and mental health;

•Had one OSHA recordable injury (supervised contractor) in 2025;

•Provided enhanced sustainability information on our website and published our 2024 Sustainability Report in June 2025, our fourth as Ecovyst;

•Continued work towards our End-of-Year 2025 sustainability goals regarding power usage and water management, and our 2030 sustainability goals regarding fuel usage, power usage, waste management, water management, responsible procurement, health, safety and environment performance, governance, and community engagement;

•Continued to reflect our core values - Stewardship, High Standards, Integrity and Engagement (“SHINE”) – in everything we do and presented SHINE awards to two employees each quarter of 2025 that were nominated by their colleagues as exemplifying the SHINE core values at work;

•Continued steps to implement additional improvements in a number of areas, including health, safety and environmental (“HSE”) performance; commitment to building a culture of respect and belonging both within our company and in our supply chain; and ethical and lawful business practices;

•Further integrated a corporate-wide sustainability software platform, which we are utilizing as an internal, real-time sustainability performance dashboard to enable improved analytics and greater visibility into our sustainability impacts; and

•Achieved a greater than 93% performance in our flagship HSE Perfect Days program in 2025, which targets at-risk behaviors and celebrates positive HSE performance across the organization on a daily basis.

The sections that follow provide some highlights of related programs and procedures.

Environmental Stewardship

Our products and technologies continue to address our customers’ sustainability challenges, tightening global regulatory standards and changing consumer preferences. We provide regeneration services that avoid significant landfill or deep well disposal of spent, or used, sulfuric acid and related hazardous and nonhazardous waste streams.

As part of our sustainability commitment regarding our own operations, we apply the principles of the Environmental Management standard of the International Organization for Standardization (ISO 14001) at our facilities. For our United States facilities, we also adhere to the Responsible Care® RC14001 Technical Specifications of the American Chemistry Council (“ACC”).

We maintain policies and procedures to monitor and control HSE risks, and to enable compliance with applicable state, national, and international HSE requirements. We have comprehensive HSE compliance, auditing and management

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programs in place to assist in our compliance with applicable regulatory requirements and with internal policies and procedures, as appropriate. Each Ecovyst facility has developed and implemented specific critical occupational health, safety, environmental, security and loss control programs.

We also have strong Health and Safety (“H&S”) and Environmental and Sustainability (“E&S”) organizations staffed by professionals who are responsible for health, safety, process safety, environmental, sustainability, product stewardship and product safety regulatory compliance. Our H&S and E&S organizational structures feature executive management-level leadership, active oversight by our Board and dedicated H&S and E&S experts on staff. We have Health, Safety and Process Safety Management leadership and also have Regional H&S Specialists and Managers who are embedded in the field and provide H&S expertise and support to operating sites. In addition, our Vice President Environmental and Sustainability oversees a team of Regional Environmental Specialists, Managers and Directors that serve our operating sites.

As an ACC Responsible Care® member company, we continue to monitor and report our HSE metrics annually. Most recently, our 2024 sustainability data for Scope 1 and 2 greenhouse gas (“GHG”) emissions, water withdrawal, and the mass of hazardous and nonhazardous waste generated was verified. GHG emissions are verified by an independent third-party to a reasonable level of assurance in accordance with the requirements of the WRI/WBSCD GHG Protocol Corporate Accounting and Reporting Standard, revised edition (2004, as amended in 2013) and the GHG Protocol Scope 2 Guidance (2015). The independent third party also verified the Company’s metrics for water withdrawal and waste generated, to a reasonable level of assurance. We included the assured data on our website and in our 2024 Sustainability Report, which we published in June 2025.

We also maintain a Product Safety and Product Stewardship management system that is compliant with the RC14001 technical specification and is supported by a dedicated Product Stewardship professional. We conduct Product Stewardship reviews as part of new product development and routinely evaluate product safety risk for raw materials, intermediates, and finished products.

Human Capital

We seek to act in a socially responsible manner through our various HSE programs as described above, our commitment to fostering a workplace culture where every employee feels respected, valued, and empowered to contribute their best, engagement with and support for the communities where we live and work, and advancement of socially responsible business practices through partnerships and other industry frameworks.

We believe that a diverse range of experiences, backgrounds, and perspectives strengthens our teams and supports innovation, safety, and long-term success. We are guided by our core SHINE values (Stewardship, High Standards, Integrity, and Engagement) and are intentional in cultivating a workplace where all team members can grow, contribute meaningfully, and thrive.

We are committed to providing equal employment opportunities for all employees and applicants for employment, and do not discriminate on the basis of race, color, religion, sex, sexual orientation, pregnancy, gender identity and expression, national origin, disability, age (40 or above), ancestry, genetic information, marital status, veteran status or any other classification protected by law. This commitment applies to all terms and conditions of employment, including recruiting, hiring, placement, advancement, training, transfer, demotion, lay off and recall, termination, compensation and benefits.

It is our policy to comply with all applicable laws and regulations in each jurisdiction in which we operate in order to provide appropriate working conditions for our colleagues. This means that we comply with applicable laws regarding the employment relationship including those that (1) prohibit child labor, (2) set acceptable working conditions and working hours, (3) provide for fair wages, including minimum wages and overtime, (4) prohibit forced or bonded labor, (5) permit freedom of association and collective bargaining, and (6) prohibit discrimination, harassment and other forms of degrading or inhumane treatment. Using tools such as our Supplier Code of Conduct and contractual provisions, we also hold our business partners to these same standards.

We support our people by acknowledging our workforce is key to our success. We offer highly competitive salaries, benefits, developmental opportunities and work/life balance. We proactively seek to attract, incentivize and retain a talented and motivated workforce. Our global performance management and succession planning processes are designed to provide sufficient talented personnel to fill key leadership, innovation and manufacturing roles well into the future and to better prepare employees for their future at the Company.

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We review our compensation and benefits programs periodically to ensure continued competitiveness. In the United States, our benefit programs are designed to help protect the health and financial well-being of our full-time employees and their family members, offering a choice of several medical & dental plans, as well as vision, flexible spending accounts, short-term and long-term disability insurance and an employee assistance program. To help our employees prepare for their future, we offer a defined contribution savings plan, which includes company contributions.

We benefit from our talented and dedicated employee population, and we actively seek to maintain a workforce that reflects the communities in which we operate. As of December 31, 2025, we had 617 employees, all of which were employed in the United States. Further, as of December 31, 2025, approximately 20% of our executives, managers and professionals were females and 20% were non-white males. As of December 31, 2025, approximately 37% of our employees were represented by a union. We believe we have good relationships with our employees and their respective unions and other bargaining representatives.

Our strengths, supported by our core values of SHINE, foster a rich culture founded on diversity of thought. We firmly believe that success is achieved through the intellect and commitment of our people, so we employ a long-term human capital program to attract, retain and develop talent for the future. We are proud of our highly collaborative teams that enable an inclusive workplace where employees are encouraged to bring their own experiences to promote innovation from all levels of the organization. This constructive work environment is supplemented with a fully integrated on-line performance management process that improves the communication of aligned goals, encourages consistent feedback and furthers employee engagement. Today, we have women on our leadership team overseeing functions that include E&S and Human Resources.

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In 2025, our sites continued to have a positive impact in the communities in which we operate. The following table outlines some of those impacts:

We also implemented a formal paid volunteer leave policy in 2025 that allows employees to take up to eight hours of paid leave each calendar year to participate in volunteer activities with approved organizations.

Governance

We maintain and consistently reinforce within our organization a series of policies and practices designed to ensure that decisions made on behalf of our company are properly made and executed. Our governance programs and policies start with a strong tone at the top and are summarized in our Executive Statement on Ethics and Compliance, which has been issued by our Chief Executive Officer and our Chief Compliance Officer and distributed throughout the organization.

The principles set forth in the Executive Statement are codified in our Code of Conduct, which sets forth the legal and ethical standards to which our employees must adhere, including (a) acting with integrity, (b) avoiding actual or apparent conflicts of interest, (c) complying with the laws and regulations of federal, state, provincial, local governments, and other appropriate regulatory agencies, (d) complying with all laws and regulations prohibiting fraud, bribery, corrupt practices, anti-competitive activities and trading with embargoed persons and countries, (e) complying with all company policies and procedures, and (f) actively promoting ethical behavior in the workplace.

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Our governance programs and policies can be found on the Company’s sustainability webpages, which are routinely updated and include a description of our enterprise risk management program and our policies on child labor, human trafficking, anti-harassment, antibribery, and cybersecurity, all of which are evaluated by third parties, including EcoVadis. In addition, the investors pages of our website contain additional materials regarding our corporate governance process, including our Board committee charters, our corporate governance guidelines, our Code of Conduct, our Supplier Code of Conduct, and other documents.

Additional Sustainability Information: Further information about our sustainability programs can be found on our website at https://www.ecovyst.com/sustainability/. The information available on our sustainability website includes our sustainability report, our sustainability goals (and how such goals map to the UN Sustainable Development Goals), materiality matrix, letters of assurance, Global Reporting Initiative (GRI) Disclosure and Sustainability Accounting Standards Board (SASB) Index, our Health Safety Environment & Security Policy Statement, our Corporate Code of Conduct, our Human Rights Policy Statement, a description of our Ethics & Compliance Complaint and Review Process, and our Labor Policy. The information contained on our website is not incorporated herein by reference and is not a part of this Annual Report on Form 10-K.

Environmental Regulations

We are subject to extensive, evolving and increasingly stringent national, state and/or local environmental laws and regulations, which address, among other things, the following:

•emissions to the air;

•discharges to soils and surface and subsurface waters;

•other releases into the environment;

•prevention and remediation of releases into the indoor or outdoor environment;

•generation, handling, storage, transportation, treatment and disposal of waste materials;

•maintenance of safe conditions in the workplace;

•registration and evaluation of chemicals;

•production, handling, labeling or use of chemicals used or produced by us; and

•stewardship of products after manufacture.

Again, we apply the principles of the Environmental Management standard of the International Organization for Standardization (ISO 14001) at our facilities, and we also adhere to the Responsible Care® RC14001 Technical Specifications of the American Chemistry Council covering health, safety, environmental, and security.

We maintain policies and procedures to monitor and control HSE risks, and to monitor compliance with applicable local, state, national and international HSE requirements. We have a strong HSE organization. We maintain a staff of professionals who are responsible for environmental, safety, health, process safety and product regulatory compliance. We have implemented a corporate audit program for all of our facilities. However, we may not be in full compliance at all times with all applicable environmental laws and regulations. We expect that stringent environmental regulations will continue to be imposed on us and our industry in general. Evolving chemical regulation programs throughout the world could impose testing requirements or restrictions on our chemical raw materials and products.

Environmental Remediation

Environmental laws and regulations require mitigation or remediation of the effects of the disposal or release of chemical substances. Under some of these regulations, as the current or former owner or operator of a property, we could be held liable for the costs of removal or remediation of hazardous substances on or under property or for natural resource damages allegedly associated with these conditions, without regard to whether we knew of or caused the contamination, and regardless of whether the practices that resulted in the contamination were permitted at the time they occurred. Many of our current or former production sites have an extended history of industrial use, and it is impossible to predict precisely what effect these laws and regulations will have on us in the future. Soil and groundwater contamination requiring investigation and remediation has been discovered at some of the sites and might occur or be discovered at other sites. Several active and former facilities currently are undergoing investigation, remediation and/or

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surveillance, including sites in Dominguez, California, Martinez, California and Hammond, Indiana. We have established and periodically update reserves for the anticipated and estimable cost of remediation at these sites

Environmental Programs

We have comprehensive HSE compliance, auditing and management programs in place to assist in our compliance with applicable regulatory requirements and with internal policies and procedures, as appropriate. Each facility has developed and implemented specific critical occupational health, safety, environmental, security and loss control programs.

We also have implemented a HSE organizational structure with executive committee level leadership and dedicated environmental experts. We have Health, Safety and Process Safety Management leadership and Regional HS Specialists and Managers who are embedded in the field and provide health and safety expertise and support to operating sites. We also have a Vice President of Environmental and Sustainability as well as Regional Environmental Specialists, Managers and Directors who are onsite to provide environmental expertise and support operating sites. Certain larger sites have dedicated environmental and health and safety personnel.

Product Safety and Product Stewardship

We have established a Product Safety and Product Stewardship management system that is compliant with the RC14001® technical specification and is supported by a dedicated Product Stewardship professional. We conduct Product Stewardship reviews as part of new product development and routinely evaluate product safety risk for raw materials, intermediates, and products.

As a chemical company, we are subject to extensive and evolving regulations regarding the manufacturing, processing, distribution, importing, exporting, and labeling of our products and raw materials.

In the US, all pertinent chemicals have been designated as “active” under the US Frank R. Lautenberg Chemical Safety for the 21st Century Act. At this time, none have been designated as chemicals which the EPA will prioritize and evaluate for regulation. Based on our chemicals and the various regulations promulgated to date, we do not anticipate costly testing requirements nor severe restrictions, but we cannot guarantee that we will not be subject to requirements for our products or raw materials that could materially affect our operations.

We remain alert for any regulatory changes which may impact our products and their end uses.

Available Information

Our website address is www.ecovyst.com. We make available free of charge through our website our Annual Report 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 and Exchange Act of 1934, as amended (“Exchange Act”), as well as reports on Forms 3, 4 and 5 filed pursuant to Section 16 of the Exchange Act, as soon as reasonably practicable after such documents are electronically filed with, or furnished to, the Securities and Exchange Commission (“SEC”). The SEC maintains an Internet website, https://www.sec.gov, which contains reports, proxy and information statements, and other information regarding our Company and other issuers that file electronically with the SEC. The information on our website is not, and shall not be deemed to be, a part of this report or incorporated into any other filings we make with the SEC.

Our Corporate Governance Guidelines, Code of Business Conduct and the charters of the Audit Committee, Compensation Committee, Nominating and Corporate Governance Committee and Health, Safety and Environment Committee of our Board of Directors are also available on our website and are available in print to any stockholder upon request by writing to Ecovyst Investor Relations, 600 Lee Road, Suite 200, Wayne, PA 19087. In accordance with SEC rules, we intend to disclose any amendment (other than any technical, administrative or other non-substantive) to the Code of Business Conduct, or any waiver of any provision thereof with respect to any of our executive officers, on our website within four business days following such amendment or waiver.