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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

For the fiscal year ended: December 31, 2023

For the transition period from                      to                     

Commission File Number: 001-36473

Trinseo PLC

(Exact name of registrant as specified in its charter)

440 East Swedesford Road, Suite 301

Wayne, PA 19087

(Address of Principal Executive Offices)

(610) 240-3200

(Registrant’s telephone number)

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 during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).    Yes  ☒    No  ☐

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

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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 Company is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ☐    No  ☒

As of February 20, 2024, there were 35,263,561 shares of the registrant’s ordinary shares outstanding.

The aggregate market value of the voting and non-voting shares of the registrant held by non-affiliates of Trinseo PLC computed by reference to the closing price of the registrant’s common shares on the New York Stock Exchange as of June 30, 2023 was approximately $441,125,346.

Documents Incorporated by Reference

Portions of the registrant’s definitive proxy statement for the 2024 annual general meeting of shareholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A of the Securities Exchange Act of 1934 are incorporated by reference into Part III of this report.

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Cautionary Note Regarding Forward-Looking Statements

This annual report on Form 10-K (“Annual Report”) contains, without limitation, statements concerning plans, objectives, goals, projections, forecasts, strategies, future events or performance, and underlying assumptions and other statements, which are not statements of historical facts. Forward-looking statements may be identified by the use of words like “expect,” “anticipate,” “believe,” “intend,” “forecast,” “estimate,” “see,” “outlook,” “will,” “may,” “might,” “potential,” “likely,” “target,” “plan,” “contemplate,” “seek,” “attempt,” “should,” “could,” “would,” or expressions of similar meaning. Forward-looking statements reflect management’s evaluation of information currently available and are based on our current expectations and assumptions regarding our business, the economy, our current indebtedness and other future conditions. Because forward-looking statements relate to the future, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict.

Specific factors that may cause future results to differ from those expressed by the forward-looking statements, or otherwise impact performance or other predictions of future actions have, in many but not all cases, been identified in connection with specific forward-looking statements. Our actual results may differ materially from those contemplated by the forward-looking statements. They are neither statements of historical fact nor guarantees or assurances of future performance. Important factors that could cause actual results to differ materially from those in the forward-looking statements include economic, business, competitive, market and regulatory conditions and the following:

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We derive many of our forward-looking statements from our operating budgets and forecasts, which are based upon many detailed assumptions. While we believe that our assumptions are reasonable, we caution that it is very difficult to predict the impact of known factors, and it is impossible for us to anticipate all factors that could affect our actual results. Accordingly, forward-looking statements should not be relied upon as a prediction of actual results. Important factors that could cause actual results to differ materially from our expectations, or cautionary statements, are disclosed under the sections entitled “Risk Factors,” “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and “Quantitative and Qualitative Disclosures About Market Risk” and in other portions of this Annual Report. All written and oral forward-looking statements attributable to us, or persons acting on our behalf, are expressly qualified in their entirety by the cautionary statements as well as other cautionary statements that are made from time to time in our other public communications. You should evaluate all forward-looking statements made in this Annual Report in the context of these risks and uncertainties.

We caution you that the important factors referenced above may not contain all of the factors that are important to you. Should unknown risks or uncertainties materialize or underlying assumptions prove inaccurate, actual results could differ materially from past results and/or those anticipated, estimated or projected. In addition, we cannot assure you that we will realize the results or developments we expect or anticipate or, even if substantially realized, that they will result in the consequences or affect us or our operations in the way we expect. The forward-looking statements included in this Annual Report are made only as of the date hereof. We undertake no obligation to publicly update or revise any forward-looking statement as a result of new information, future events or otherwise, except as otherwise required by law.

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Trinseo PLC

Form 10-K Annual Report

For the Fiscal Year Ended December 31, 2023

Unless otherwise indicated or required by context, as used in this Annual Report on Form 10-K (“Annual Report”), the term “Trinseo” refers to Trinseo PLC (NYSE: TSE), a public limited company existing under the laws of Ireland, and not its subsidiaries. The terms “Company,” “we,” “us” and “our” refer to Trinseo and its consolidated subsidiaries, taken as a consolidated entity. Trinseo PLC is the surviving entity of a cross-border merger with our predecessor company, Trinseo S.A., which merger was completed in October 2021. All financial data provided in this Annual Report is the financial data of Trinseo PLC, unless otherwise indicated. Prior to the formation of Trinseo S.A., our business was wholly owned by The Dow Chemical Company (together with other affiliates, “Dow”).

The Company may distribute cash to shareholders under Irish law via dividends or distributions made out of distributable profits. See Item 5, “Ireland Tax Considerations,” for further information.

Definitions of capitalized terms not defined herein appear in the notes to our consolidated financial statements. Specifically, refer to Note 17 in the consolidated financial statements for definitions of the Company’s debt facilities.

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Our Strategy

In 2023, we continued to focus our efforts and investments on a strategy to transform Trinseo into a specialty materials and sustainable solutions provider focusing on product offerings which are less cyclical and offer significantly higher growth and margin potential. In pursuit of this transformational goal, we have invested, and will continue to invest, in product offerings serving the applications within our compounding business segments, as well as coatings, adhesives, sealants, and elastomers (“CASE”) applications within the Latex Binders business segment.

In support of our strategy and to improve our footprint as a sustainable solutions provider, in January 2022, we completed the acquisition of Heathland B.V. (“Heathland”). Heathland is based in Utrecht, the Netherlands, and is focused on converting post-consumer and post-industrial polymethyl methacrylates (“PMMA”), polycarbonate (“PC”), acrylonitrile-butadiene-styrene (“ABS”), polystyrene, and other thermoplastic waste for use in a wide range of high-end applications. In April 2023 we announced the inauguration of a polycarbonate (PC) dissolution pilot facility in our Terneuzen, the Netherlands plant, which will be used to manufacture recycled polymers, and is another step in realizing our sustainability goals. We continue to evaluate strategic alternatives to divest all or a portion of our styrenics businesses, which includes our Polystyrene and Americas Styrenics reporting segments. The styrenics business separation remains an integral part of our transformation strategy, and we continue to evaluate actions to transform the Company into a higher growth, higher margin and less cyclical specialty and sustainable materials provider.

We believe that there are still significant opportunities to improve our business and enhance our position as a specialty materials and sustainable solutions provider by continuing to enhance our existing portfolio, and by expanding on businesses we have acquired. In addition to our transformation strategy, the Company continues to seek organic growth through expansion into key markets or strategic capital investments targeting technologies and solutions that meet the evolving needs of our customers, and to continue to provide innovative products to our customers who seek our technological and development capabilities to create specialty grades, new and sustainable products, and technologically-differentiated formulations. The Company will continue to focus on growing margins and reducing earnings volatility through such organic investments, as well as through divestitures of other less strategic businesses or assets in our portfolio. The strategic acquisitions and investments that we have pursued have attractive risk-adjusted returns in markets and geographies that we believe have the best opportunity for growth as well as opportunity for cost-saving synergies. In addition, beginning in December 2022 and continuing through 2023, we implemented restructuring initiatives designed to reduce costs, optimize assets, improve profitability, reduce our exposure to cyclical markets and strengthen our competitive position through the closure of certain underperforming or uncompetitive plants and product lines.

We remain committed to maintaining a strong financial position with appropriate financial flexibility and liquidity. The Company employs a disciplined approach to capital allocation and deployment of cash that strives to balance the growth of our business, and continued cash generation, while providing returns to our shareholders.

The priorities for uses of available cash include the servicing of our debt, the funding of targeted growth initiatives, and the continued return of capital to our shareholders via quarterly dividends and the repurchase of our ordinary shares, when deemed appropriate. Management believes that consistent cash flow generation, spending discipline and continued investment in higher margin, differentiated products are critical to providing the Company with the ongoing flexibility to pursue our business strategy.

For more information regarding our strategic highlights see Item 7 – Management’s Discussion and Analysis of Financial Condition and Results of Operations – 2023 Highlights.

Business Segments

In 2023, the Company operated under six reporting segments: Engineered Materials, Latex Binders, Plastics Solutions, Polystyrene, Feedstocks, and Americas Styrenics. Beginning in 2024, the Company will no longer manufacture styrene, and will no longer report the results of the Feedstocks segment. Our reporting segments reflect the model under which the business is being managed and results are being reviewed by the Chief Executive Officer, who is the Company’s chief operating decision maker.

For information regarding net sales, Adjusted EBITDA, the performance metric used by management to evaluate our segments’ performance, and capital expenditures by segment, as well as sales and long-lived assets by geographic area, refer to Note 24 in the consolidated financial statements.

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Engineered Materials Segment

Overview

Our Engineered Materials segment consists of rigid thermoplastic compounds and blends products, soft thermoplastic products, continuous cast, cell cast and extruded PMMA sheet products, and PMMA resins. Products in this segment are primarily targeted toward higher growth and higher margin applications primarily in consumer electronics, medical, footwear, automotive and building & construction. The PMMA business also includes production of activated methyl methacrylates (“MMA”) in Europe primarily for our own consumption in producing PMMA with the remainder sold into the merchant market. Our MMA production process yields ammonium sulfate as a byproduct which is sold into the market.

In 2023, approximately 34% of total Engineered Materials net sales were generated in Europe, approximately 52% were generated in the United States, and approximately 12% were generated in Asia.

Products and End Uses

Products in the Engineered Materials segment are split into rigid compounds, soft plastic compounds, and PMMA resins and sheets. Rigid compounds include PC compounds, ABS compounds, and PC blends, mostly PC/ABS, and support primarily the consumer electronics and medical markets for equipment housing applications. Thermoplastic elastomer (“TPE”) soft plastic compounds are focused on supporting footwear shoe sole applications, personal care, consumer electronics, and automotive high-end applications such as overmolds, sealings, tubing, and films. PMMA products can be sold as resin compounds or sheets produced through continuous-cast, extrusion, and cell-cast processes. PMMA products are sold primarily into building & construction, automotive, medical and consumer goods applications.

The benefit of Trinseo’s portfolio in our Engineered Materials segment is the high level of customization for high-end applications at selected premium brand owners, and clear orientation to sustainable solutions. Our current portfolio includes sustainable solutions, such as high-content post-consumer recycled (“PCR”) polycarbonate and bio-based raw materials. We are developing further solutions to expand our sustainable offering using PCR ABS, PCR TPE, PCR PMMA and recycled MMA (“R-MMA”), which is chemically recycled. Sustainable products represented 3% of Engineered Materials segment volume in 2023 and are a core growth area.

We sell our rigid compounds products mainly under the EMERGE brand for consumer electronics, and under the CALIBRE brand for medical markets. We sell our PMMA products primarily under PLEXIGLAS in the United States and ALTUGLAS in Europe and Asia. We foresee growth and robust demand in applications of building & construction, consumer goods, and automotive as well as continued initiatives toward light-weighting, paint replacement and digitization. Supported by current macro trends, specifically as it relates to safety and health, remote servicing and working, and sustainability, we believe that we have additional growth opportunities in existing consumer electronics applications, including tablets, notebooks, smart phones and other handheld devices, as well as new voice control systems, home entertainment and delivery equipment. We also foresee growth in medical wearables, home equipment, and drug delivery devices. In serving these markets, we leverage our polymer and compound technologies to meet increasingly stringent performance requirements along with our customers’ aesthetic and color-matching requirements, which are crucial characteristics for the products involved.

We sell our PMMA sheet products primarily under the trade names ALTUGLAS, PLEXIGLAS, ACRYSPA, AVONITE and STUDIO. We foresee growth in wellness applications such as hot tubs and swim spas as well as sanitary applications like bathtubs. More specifically, we are able to effectively serve these markets through our specialized continuous cast sheet production capabilities that allow us to provide large scale PMMA sheet with specific color requirements. We have also expanded our product offerings into transportation applications and continue to provide customer solutions in architectural applications such as signage and countertops.

We manufacture our TPE soft plastic compounds principally under the trade names MEGOL, APILON, APIGO, and APINAT. Growth in footwear is supported by bio thermoplastic polyurethane (“TPU”) solutions in both luxury and sport premium markets, while automotive growth is orientated to hygienic interiors and both robust and smart surfaces.

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Competition and Customers

Our main competitors are Sabic, Covestro, Styrolution, LG Chem, and Kingfa for rigid technologies, Kraiburg, Celanese, Avient, Hexpol and BASF for TPEs, and Rohm, Plaskolite, Mitsubishi Chemicals and Schweiter Technologies for PMMA resins and sheets.

We compete in the Engineered Materials segment primarily based on our ability to offer differentiated and reliable products, high quality customer service, and deep relationships with prioritized customers. We believe that growth in this segment will stem from the continued high demand for engineered and sustainable product solutions serving the consumer electronics, automotive, building & construction, wellness, footwear, medical and lighting application markets. We believe our track record of innovation and our focus on differentiated products enhances our growth prospects in this segment. We also believe that our global organization and facilities are a competitive advantage that allows us to provide customers with consistent grades across different regions and positions us to strategically serve emerging markets.

Seasonality

Due to the steady demand state of a portfolio of applications in many markets, such as consumer electronics, medical devices, and footwear, rigid compounds and soft TPE products do not experience significant seasonality. PMMA applications do experience some seasonality due to exposure to automotive, building and construction and wellness markets.

Latex Binders Segment

Overview

We are a global leader in styrene-butadiene latex (“SB latex”), holding a strong market position across the geographies and applications in which we compete, including the #1 position in SB latex capacity in Europe and the #1 position in capacity in North America, based on third party data. In 2023, approximately 53% of our Latex Binders segment’s sales were generated in Europe, 28% were generated in the United States, and the majority of the remaining net sales were generated in Asia. Additionally, this segment includes the results of our styrene-acrylate latex (“SA latex”) production facilities and related infrastructure in the United States, Europe and Asia. As noted above, as part of the Company’s transformational strategy, our key area of focus in the Latex Binders segment is to grow our product offerings serving CASE applications, as these offer significantly higher growth and margin potential.

Products and End Uses

We hold the #1 position for supplying latex binders for the coated paper and board market globally. SB latex is widely used as a binder for mineral pigments as it allows high coating speeds, improved smoothness, higher gloss level, opacity and water resistance that is valued in the product’s end use in advertising, magazines, and packaging board coatings.

We are also the #1 supplier of latex binders to the carpet and artificial turf market and offer a diverse range of products for use in residential and commercial applications. We produce SB latex, SA latex, vinylidene chloride, and butadiene-methacrylate latex products for the commercial and niche carpet markets. SB latex is also used in flooring as an adhesive for carpet and artificial turf fibers. We continue to implement new chemistries for paper coating and carpet backing applications.

We also offer a broad range of performance latex binders products, including SB latex, SA latex, and vinylidene chloride latex for CASE applications. Net sales to CASE applications made up approximately 14% of total Latex Binders net sales in 2023, with margins of approximately two times the average of products serving all applications within the segment.

Competition and Customers

Our principal competitors in our Latex Binders segment include BASF Group and Synthomer plc. In this segment, we compete primarily based on our ability to offer differentiated and reliable products, the quality of our customer service, and the length and depth of our relationships. This industry has seen capacity reduction and consolidation which we believe could positively impact our competitive standing.

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We believe our Latex Binders segment is able to differentiate itself by offering customers value-added formulations and product development expertise. Our R&D team and Technical Services and Development (“TS&D”) team are able to use our pilot coating facility, paper fabrication and testing labs, carpet technology centers located near carpet producers, and product development and process research centers to assist customers in designing new products and enhancing their manufacturing processes. Many of our major customers rely on our dedicated R&D and TS&D teams to complement their limited in-house resources for formulation and reformulation tests and trials. We believe that this capability allows us to capture new business, strengthen our existing customer relationships and broaden our technological expertise.

Additionally, our global manufacturing footprint is key in allowing us to serve our customers in a cost-effective manner, as latex binders products are costly to ship over long distances due to their high water content. We believe that our global network of service and manufacturing facilities is highly valued by our customers. We seek to capture the value of our R&D and TS&D services and manufacturing capabilities through our pricing strategy. In 2023, we estimate that more than half of net sales in this segment related to contracts that include raw material pass-through clauses.

Seasonality

Reporting periods impacted by the winter season and unfavorable weather conditions that typically affect the construction and building materials end markets may result in seasonally lower performance, particularly in the CASE applications of our Latex Binders segment.

Plastics Solutions Segment

Overview

Our Plastics Solutions segment consists of a variety of compounds and blends, the majority of which are for automotive applications. The segment also includes our ABS, styrene-acrylonitrile (“SAN”), and PC businesses. The Plastics Solutions segment also includes the results of the Heathland Acquisition, which is focused on converting post-consumer and post-industrial PMMA, PC, ABS, polystyrene, and other thermoplastic waste for use in a wide range of high-end applications. In 2023, approximately 56% of net sales from our Plastics Solutions segment were generated in Europe, 34% were generated in North America, and 11% were generated in Asia. On January 1, 2023, the Base Plastics segment was renamed Plastics Solutions to better reflect the Company’s strategic focus on providing solutions in areas such as sustainability and material substitution.

Products and End Uses

Copolymers. Our copolymers products consist of ABS and SAN. In 2023, copolymers represented approximately 56% of total segment net sales.

We are a leading producer of ABS in Europe and are one of the few global producers, with additional presence in both North America and China. We produce mass ABS (“mABS”), a variation of ABS that has lower conversion and capital costs compared to the more common emulsion ABS (“eABS”) process, marketed under our MAGNUM brand. mABS has similar properties to eABS but has greater colorability, thermal stability and lower gloss. mABS products can be manufactured to stricter specifications because they are produced in a continuous process as opposed to the batch process used in eABS. mABS also has environmental benefits such as waste reduction and higher yields. In addition to our own mABS production capacity, we have licensed our proprietary mABS technology to other producers.

Primary end uses for our ABS products include automotive and construction sheet applications. We maintain a significant share of ABS sales into these markets, which we believe is due to the differentiating attributes of our mABS products, our reputation as a knowledgeable and reliable supplier, our broad product mix, and our customer collaboration, including design capabilities.

SAN is composed of styrene and acrylonitrile, which together provide clarity, stiffness, an enhanced ability to be processed, mechanical strength, barrier properties, chemical resistance and heat resistance. Our SAN products are manufactured in Terneuzen, The Netherlands and are used mainly in appliances, consumer goods and construction sheets, due to their low cost, clarity and chemical resistance properties.

PC. Our PC products are manufactured in Stade, Germany and are sold into various markets as well as consumed internally for our compounding products. In 2023, PC represented approximately 9% of total segment net sales.

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PC has high levels of clarity, impact resistance and temperature resistance. PC can be used in its neat form (prior to any compounding or blending) for markets such as construction sheets and profiles, medical and lighting. Additionally, PC can be compounded or blended with other polymers, such as ABS, which imparts specific performance attributes tailored to the product’s end use.

Our products for glazing and construction sheets are marketed under the CALIBRE brand name and offer customers a combination of clarity, heat resistance and impact performance.

We approved an asset restructuring plan in the fourth quarter of 2022, which includes the closure of one PC production line to reduce our exposure to the cyclical merchant PC market. We continue to produce PC for use in our downstream compounding business with the remaining assets.

Compounding. Our compounding products consist of PC/ABS compounds, PC blends, and PC and polypropylene compounds. In 2023, compounding products represented approximately 35% of total segment net sales.

We have a significant position in PC/ABS blends, which combine the heat resistance and impact strength of PC with the easy-to-process qualities and resilience of ABS. We have also developed compounds containing PCR content in their products. We believe our ability to offer technologically-differentiated products to meet customer needs sets us apart from our competitors, and with our history as a leading innovator in compounds and blends, we have established ourselves as a leading supplier of PC-based products.

For the automotive industry, we manufacture PC/ABS blends under the PULSE brand, and we innovate collaboratively with our customers to develop performance solutions to meet industry needs, such as reducing the weight of vehicles or providing products using recycled or sustainable content. As a result, we are a key supplier of these products to leading automotive companies in North America and Europe, who tend to specify these products on a per car platform basis, making it difficult to be displaced as a supplier once selected and providing us with relatively stable and predictable cash flows for several years during the production lifecycle. We have an established position in China and are working to further increase our presence in Asia.

Competition and Customers

Our principal competitors in our Plastics Solutions segment are Covestro AG, Saudi Basic Industries Corporation, INEOS Styrolution, Versalis, Shanghai Kumho Sunny Plastics Co., Ltd., Shanghai Pret Composites Co. Ltd., LG Chem, and Lotte Chemical Corporation. In our Plastics Solutions segment, we compete primarily based on our ability to offer differentiated and reliable products, the quality of our customer service and the length and depth of our customer relationships.

We believe potential growth in the Plastics Solutions segment will be impacted by a number of factors, including consumer preference for lighter-weight and impact-resistant products. Additionally, we believe growth prospects are bolstered by sustainability trends such as electric vehicles and potential government mandates, such as the substitution of lighter-weight plastics for metal in automobiles. Therefore, we believe our history of innovation and our focus on differentiated products enhances our growth prospects in this segment. Our innovation has contributed to long-standing relationships with customers who are recognized leaders in their respective end markets. We also believe our global facilities are a competitive advantage that allows us to provide customers with consistent grades across different regions, and positions us to strategically serve emerging markets.

Seasonality

Reporting periods impacted by the winter season and unfavorable weather conditions that typically affect the construction and building materials end markets may result in seasonally lower performance in our Plastics Solutions segment.

Polystyrene Segment

Overview

We are a leading producer of polystyrene, with multiple plants in Europe and Asia, and focus on sales to injection molding and thermoforming customers. In 2023, approximately 65% of net sales from our Polystyrene segment were generated in Europe and 35% of net sales were generated in Asia.

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Products and End Uses

Our product offerings include a variety of general purpose polystyrenes (“GPPS”) and high impact polystyrene (“HIPS”). HIPS is polystyrene that has been modified with polybutadiene rubber to increase its impact resistant properties. These products provide customers with performance and aesthetics at a relatively low cost across applications, including appliances, packaging, including food packaging and food service disposables, consumer electronics and building and construction materials.

The STYRON™ brand is one of the longest established brands in the industry and is widely recognized in the global marketplace. We believe our R&D capabilities provide valuable, differentiated solutions for our customers, making us well-positioned to address the sustainability, weight reduction, and safety needs.

In 2023 we continued offering recycled polystyrene for food packaging applications for some of our customers through both dissolution and chemical recycling technology. We view recycled polystyrene products as important not only for the benefit of the environment but also as a way to better serve our customers by addressing their need for sustainable solutions.

Competition and Customers

Our principal competitors in our Polystyrene segment are INEOS Styrolution, Versalis S.p.A., Total S.p.A., Sinopec Corp., Formosa Chemicals & Fibre Corp., and Chi Mei Corporation. In this segment, we compete primarily based on our ability to offer reliable and innovative products as well as the quality of our customer service, operational reliability and the length and depth of our relationships.

Our customer-centric model focuses on understanding customers’ needs and developing tailored relationships that add value beyond the value of the actual product performance. For durable applications, we focus our efforts on product design engineering initiatives for developing and specifying plastics in the next generation of construction applications and appliances. In non-durable applications, we focus on innovative products that provide clear cost advantages to our customers, serving customers with our cost-advantaged technology and operating excellence. We are also able to offer various sustainable product innovations in our non-durable applications, especially packaging. We have leveraged industry-leading product development and technology capabilities in many of our product lines in this segment to develop long-standing customer relationships, including with a number of customers who have purchased from us, including our predecessor business operated by Dow, for more than 20 years. We believe that our asset footprint is an advantage, allowing us to provide customers with consistent product grades and positioning us to strategically serve growth economies.

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Seasonality

Due to the geographic diversity of the Company’s customers and end markets for our polystyrene products across the globe, our Polystyrene segment does not typically experience material levels of seasonality. However, sales volumes may fluctuate from quarter-to-quarter as customers may adjust their purchasing patterns based on their expectations of polystyrene price changes caused by underlying raw material cost changes.

Feedstocks Segment

Overview

The Company is a large consumer of styrene monomer globally. Historically, the primary function of our Feedstocks segment was the production of styrene monomer in Europe in order to provide secure sourcing of this key raw material to our other segments. Overall, our Feedstocks nameplate capacity was 9% of the West European styrene monomer capacity in 2023. In 2022 we approved an asset restructuring plan which included the closure of manufacturing operations at our styrene production facility in Boehlen, Germany and in 2023 approved the closure of our Terneuzen, The Netherlands styrene plan. Once closed, the Company will no longer produce styrene, and will purchase all of our styrene needs from third parties. Refer to Item 7 – Management’s Discussion and Analysis of Financial Condition and Results of Operations – 2023 Highlights for further information.

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Products and End Uses

Styrene monomer is a basic building block of plastics and a key input to many of the Company’s products. Styrene monomer is a key raw material for the production of polystyrene, expandable polystyrene, SAN resins, SA latex, SB latex, ABS resins, and unsaturated polyethylene resins.

Competition and Customers

Our principal competitors in our Feedstocks segment were: INEOS Styrolution, Versalis S.p.A., Total S.p.A., BASF SE, Saudi Basic Industries Corporation, LyondellBasell, Repsol PLC, and Royal Dutch Shell plc. The majority of styrene monomer produced within the Feedstocks segment was consumed by the Company in our own manufacturing activities.

Global styrene operating rate percentages were around 69% in 2023 and we believe they will stay in the low 70% range over the next several years before returning to 80% levels. The operating rate could be positively impacted by the potential closure of higher-cost styrene plants. Effective operating rates can, from time to time, be impacted by planned and unplanned outages, leading to periods of elevated margins.

Seasonality

Our Feedstocks segment did not generally experience material levels of seasonality affecting sales volumes; however, there were occasional seasonal fluctuations in margin as planned supply outages generally occurred more often in the spring and fall seasons.

Americas Styrenics Segment

Overview

This segment consists solely of the operations of our 50%-owned joint venture with Chevron Phillips Chemical Company, Americas Styrenics LLC (“Americas Styrenics”), which continues to be a leading producer in North America of both styrene and polystyrene. In 2023, Americas Styrenics was the #1 producer of polystyrene, based on capacity data, and supplied 18% of the styrene monomer capacity in North America. We received a total of $65.0 million in cash dividends from Americas Styrenics during 2023. We estimate that the contribution to our equity earnings from Americas Styrenics’ polystyrene business was approximately 88% in 2023, 71% in 2022, and 72% in 2021.

Products and End Uses

Styrene monomer is a basic building block of plastics and a key input to many of the Company’s products. Styrene monomer is a key raw material for the production of polystyrene, and in 2023 approximately 60% of the styrene monomer produced by Americas Styrenics was consumed in its own production of polystyrene. The remainder of Americas Styrenics’ product is sold as a key raw material to other manufacturers of polystyrene, expandable polystyrene, SB latex, ABS resins, unsaturated polyethylene resins, and styrene-butadiene rubber.

Americas Styrenics also produces GPPS, high heat, high impact resin, and STYRON A-TECH™ polystyrene products. Major applications for these polystyrene products include appliances, food packaging, food service disposables, consumer electronics, and building and construction materials.

Competition and Customers

Americas Styrenics’ principal competitors are INEOS Styrolution, Total S.p.A., and LyondellBasell. In our Americas Styrenics segment, we compete primarily based on our ability to offer reliable products as well as the quality of our customer service and the length and depth of our relationships.

As a leading styrenics producer in North America, this segment is well-positioned to benefit from consolidation dynamics in the styrene and polystyrene industries within the region. As noted above in the Feedstocks segment section, global styrene operating rate percentages were around 69% in 2023 and we believe they will stay in the low 70% range over the next several years before returning to 80% levels, with the potential for positive upside if there are closures of higher-cost styrene plants. Effective operating rates can, from time to time, be impacted by planned and unplanned outages, leading to periods of elevated margins.

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Seasonality

Reporting periods impacted by the winter season and unfavorable weather conditions that typically affect the construction and building materials end markets may result in seasonally lower performance in our Americas Styrenics segment.

Our Relationship with Dow

Following the Dow Separation, we entered into certain long-term agreements with Dow to provide services that would ease our transition into a standalone company. In recent years, the Company has successfully migrated a substantial level of systems and services support away from Dow. However, we continue to maintain a significant relationship with Dow for certain technology and site services, as well as the supply of certain key raw materials. The failure of Dow to perform their obligations, or the termination of these agreements, could adversely affect our operations. See Item 1A—Risk Factors for more information.

We are party to various site services agreements (“SAR SSAs”) for Dow to provide site services to the Company at Dow-owned sites. Conversely, we entered into similar agreements with Dow, where, at Company-owned sites, we provide such services to Dow. These agreements cover general services that are provided at certain facilities co-located with Dow, including utilities, site administration, environmental health and safety, site maintenance and supply chain. These agreements generally have 25-year terms and include options to renew. These agreements may be terminated at any time by agreement of the parties, or, by either party, for cause or under certain circumstances for a material breach. In addition, we may terminate with 12-months’ prior notice to Dow any services identified in any SAR SSA as “terminable.” Highly integrated services, such as electricity and steam, generally cannot be terminated prior to the termination date unless we experience a production unit shut down for which we provide Dow with 15-months’ prior notice, or upon payment of a shutdown fee. Upon expiration or termination, we would be obligated to pay a monthly fee to Dow for a period of 45 to 60 months following the expiration or termination of such SAR SSA. The agreements under which Dow receives services from us may be terminated under the same circumstances and conditions.

Additionally, we are party to several agreements with Dow for the provision of certain raw materials, products and services and other operational arrangements. In connection with the 2021 acquisition of the PMMA and MMA businesses from Arkema S.A. (the “PMMA Acquisition”), the Company assumed a Capacity Reservation Contract (“CRC”) which is an evergreen contract that provides guaranteed access to a certain portion of MMA capacity at a Dow-owned manufacturing facility in North America. See Sources and Availability of Raw Materials for more information.

Under the Amended and Restated MOD5 Computerized Process Control Software, Licenses and Services Agreement, with Rofan Services (“AR MOD5 Agreement”), Dow provides worldwide process control technology, including hardware, software licenses and support services, and related enterprise resource planning services. The AR MOD5 Agreement has a term through December 2023 and may be terminated by either party for cause or uncured material breach; by the Company if we no longer wish to receive maintenance and support for any licensed software; or by Dow if we use the licensed software for any purposes other than Company business. Dow may terminate the maintenance and support terms at any time if we fail to make payments when due. With the exception of one remaining site, as of December 31, 2023, we have converted all other plant locations from the MOD5 process control technology and are no longer reliant on Dow for this service. We expect to convert the remaining site by the end of 2024.

The Second Amended and Restated Master Outsourcing Services Agreement (“SAR MOSA”) provides for ongoing worldwide services, substantially all of which were no longer provided by Dow as of December 31, 2020, following our transition of these services over the last several years. The Company did not incur significant costs related for the SAR MOSA in 2023, nor do we expect to incur any further costs going forward.

For the years ended December 31, 2023, 2022, and 2021, we incurred a total of $140.5 million, $273.9 million, and $214.9 million, respectively, in expenses under the SAR MOSA, AR MOD5 Agreement, and SAR SSAs (which include utilities), including $138.5 million, $270.6 million, and $210.3 million, respectively, for both the variable and fixed cost components of the site services agreements and $2.0 million, $3.3 million, and $4.5 million, respectively, covering all other agreements.

For the years ended December 31, 2023, 2022, and 2021, purchases and other charges from Dow and its affiliated companies (excluding the SAR MOSA, AR MOD5 Agreement, and SAR SSAs) were approximately $570.5 million, $688.7 million, and $1,143.9 million, respectively. These purchases and other charges primarily relate to the purchase of

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raw materials for manufacturing our products. Additionally, for the years ended December 31, 2023, 2022, and 2021, sales to Dow and its affiliated companies were approximately $95.1 million, $146.7 million, and $156.4 million, respectively.

We have supply contracts in place to help maintain our supply of raw materials at competitive market prices and seek to implement the most efficient and reliable raw material strategy for each of our segments, including utilizing multiple sources where feasible and maintaining a balance between contracted and spot purchases of raw materials. We also produce raw materials for use by our businesses, such as styrene monomer, PC, and MMA, and we purchase PCR materials for use in products such as our PC compounds.

In 2023, we obtained approximately 21% of our raw materials from Dow (based on aggregate purchase price). In 2023, Dow supplied us with approximately 100% of our benzene requirements and 100% of our ethylene requirements. While we have terminated our benzene and ethylene purchase agreements from Dow, Dow continues to be a significant supplier of butadiene. Our current supply agreement with Dow for butadiene commenced in 2021 and has a term of five years, with automatic renewal for 2 years. PMMA products use MMA as the key raw material, which is sourced through both our own production in Europe and through supply agreements. During 2023, Dow has supplied us with an aggregate 54% of the MMA used in our PMMA production, both in the United States through various supply agreements.

In 2023 we obtained 75% of our styrene supply through long-term strategic contracts and spot market purchases. With this mix of purchased and produced styrene, we seek to optimize our overall costs of securing styrene through efficient logistics, manufacturing economics and market dynamics. From November 2023 onward, we now obtain 100% of our styrene supply through long-term strategic contracts and spot market purchases. This follows the closure of our Terneuzen Styrene facility.

Bisphenol A (“BPA”) is the major raw material associated with PC production. In 2023 we changed to new BPA sources including using Asian material to supply our PC operation in Stade, Germany. Acetone, a key material for producing MMA, is supplied via long term agreements with Versalis in Europe.

Technology

Our R&D and TS&D activities across our segments focus on identifying needs in our customers’ end markets. As part of our customer-centric model, our R&D/TS&D organization interfaces with our sales and marketing teams and directly with customers to determine their product requirements, considering industry and market segment trends. This information is used to select R&D/TS&D projects that are value-enhancing for both our customers and the Company.

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Our innovation and technology centers support our technological and R&D/TS&D capabilities. In addition, our R&D/TS&D efforts are also supported by certain “mini-plants” operated by our businesses in Stade. These mini plants are used to make samples of experimental products for testing, which we believe is a critical step in our new product development process. We also operate a plastics research center, which integrates two existing technical support centers and research lab operations in a single location at our Terneuzen, The Netherlands office location. Further, we operate pilot plants to facilitate new production technology, including a TPE pilot facility in Hsinchu, Taiwan which enables close collaboration with Asia Pacific customers for sustainably advantaged materials in targeted markets including consumer electronics, medical, footwear, and automotive. Finally, two R&D centers in Europe and three R&D centers in the United States, are responsible for the design of PMMA products at the Company’s eight global acrylic manufacturing plants.

R&D and TS&D costs are included in expenses as incurred. Our R&D and TS&D costs were $57.6 million, $51.4 million, and $63.9 million for the years ended December 31, 2023, 2022, and 2021, respectively.

Sales and Marketing

We have a customer-centric business model that has helped us to develop strong relationships with many customers. Our sales and marketing professionals are primarily located at our facilities or at virtual offices within their respective geographies. We have approximately 217 professionals working in sales and marketing around the world, along with approximately 105 customer service professionals and we sell our products to customers in approximately 80 countries. We primarily market our products through our direct sales force. Typically, our direct sales are made by our employees in the regions closest to the given customer.

Intellectual Property

We evaluate on a case-by-case basis how best to utilize patents, trademarks, copyrights, trade secrets and other intellectual property to protect our products and our critical investments in research and development, manufacturing and marketing. We focus on securing and maintaining patents for certain inventions, while maintaining other inventions as trade secrets, derived from our customer-centric business model, to maximize the value of our product portfolio and manufacturing capabilities. Our policy is to seek appropriate protection for significant product and process developments in the major markets where the relevant products are manufactured or sold. Patents may cover products, processes, intermediate products and product uses. Patents extend for varying periods in accordance with the date of patent application filing and the legal life of patents in the various countries. The protection afforded, which may also vary from country to country, depends upon the type of subject matter covered by the patent and the scope of the claims of the patent. The intellectual property that we have created or acquired since our formation covers areas such as material formulations, material process technologies and various end-use industrial applications.

In most industrial countries, patent protection may be available for new substances and formulations, as well as for unique applications and production processes. However, given the geographical scope of our business and our continued growth strategy, there are regions of the world in which we do business or may do business in the future where intellectual property protection may be limited and difficult to enforce. We maintain strict information security policies and procedures wherever we do business. These information security policies and procedures include data encryption, controls over the disclosure and safekeeping of confidential information, as well as employee awareness training. 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.

The technologies we utilize in some of our businesses have been in use for many years (e.g., SB latex, polystyrene, PMMA and ABS) and a number of our patents relating to such technologies have expired or will expire in the future. As patents expire, or are allowed to lapse, the products and processes described and claimed in those patents become generally available for use by the public. We believe that the expiration of any single patent or family of patents that is scheduled to expire would not materially adversely affect our business or financial results. We believe that our trade secrets relating to manufacturing and other processes used in connection with products to which expiring patents relate will continue to provide us with a competitive advantage after the expiration of these patents.

We use trademarks as a means of differentiating our products. We protect our trademarks against infringement where we deem appropriate. We have successfully registered the TRINSEO™ trademark in 130 countries, and also own

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the Plexiglas®, Altuglas®, Solarkote® and Oroglas® marks as well as other trademarks acquired in the PMMA Acquisition.

Dow has either transferred to us or granted perpetual, royalty-free licenses to us to use Dow’s intellectual property that was used by Dow to operate the acquired business (the “Dow Acquired Business”) prior to the Dow Separation. This intellectual property includes certain processes, compositions and apparatus used in the manufacture of certain of our legacy products. In addition to our license rights to use Dow’s intellectual property related to the Dow Acquired Business, we have obtained licenses to use Dow’s intellectual property to the extent necessary to perform our obligations under the contracts transferred to us in the Dow Separation and to use such intellectual property (other than patents) for products outside of the Dow Acquired Business as it was conducted by Dow prior to the Dow Separation, subject to certain limitations. While we believe our license rights with respect to Dow’s intellectual property are sufficient to allow us to operate our current business, growth opportunities, involving new products may fall outside of our license rights with Dow. Therefore, our ability to develop new products may be impacted by intellectual property rights that have not been licensed to us by Dow. We have the right, with Dow’s cooperation, to directly enforce the patents that are exclusively licensed to us by Dow where infringement is primarily within the scope of our business; but nothing obligates Dow to enforce against third parties the intellectual property rights of Dow that are licensed to us on a non-exclusive basis or where the infringement is primarily outside the scope of our business.

Environmental, Health, Safety and Product Stewardship

Obtaining, producing and distributing many of our products involve the use, storage, transportation and disposal of toxic and hazardous materials. We are subject to extensive, evolving and increasingly stringent national and local environmental and safety laws and regulations, which address, among other things:

We monitor compliance with applicable state, national, and international environmental, health and safety requirements and maintain policies and procedures to monitor and control environmental, health and safety risks, which may in some circumstances exceed the requirements imposed by applicable law. We have a strong environmental, health and safety organization with a staff of professionals who are responsible for environmental, health, safety and product regulatory compliance and stewardship, in addition to comprehensive standards and tools. We supplement our programs with our participation in trade associations which monitor developments in legislation impacting our businesses. Additionally, our Supplier Code of Conduct includes our expectations for our suppliers to comply with applicable laws and regulations and encourages them to adhere to the highest principles of environmental responsibility.

We follow the American Chemistry Council Responsible Care® Guiding Principles for our global facilities and products and have received third party certification of our Responsible Care® Management System. Many of our facilities have been certified to ISO 14001 and other ISO management systems. We have a mature corporate environmental, health and safety audit program for all of our facilities. We focus on emergency preparedness, crisis planning and drills, at both the facility and corporate level. We expect that stringent environmental regulations will continue to be imposed on us and our industry in general.

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Sustainability and Climate Change

We recognize that climate change has had and will continue to have significant impacts on our environment, particularly as it relates to extreme weather conditions and rising sea levels, and which has prompted regulations limiting, among other things, the emission of greenhouse gases. In the countries in which we operate, particularly in the EU, we are required to comply with increasingly extensive regulations to address climate change impacts and resource conservation requirements. We also monitor legislative actions and their potential impacts on the end markets we serve.

We track and publicly report our greenhouse gas emissions, water usage, waste, and energy consumptions and our facilities work to improve our performance at reducing chemical emissions, water usage and energy consumption. Our Sustainability and Corporate Social Responsibility Report (the “Sustainability Report”), which is available on our website, provides our most recent sustainability highlights for our products, performance and operations. The report highlights sustainability goals and other initiatives to improve our sustainability performance.

Sustainability is a key focus area of our long-term strategy and during 2023 we continued to take actions to further our offering of sustainable products. In April 2023 we announced the inauguration of a polycarbonate dissolution pilot facility in our Terneuzen, the Netherlands site, to test a physical recycling process where the polymer is extracted by the use of solvents which are used to make new recycled polymers. The dissolved PC extracted is 100% recycled PC that could be used for compounding into new materials for an array of applications, such as mobile phone casing, printer enclosure or automotive parts. We continue to publish an annual Sustainability Report with reference to the Global Reporting Initiative (“GRI”) framework, the Sustainability Accounting Standards Board (“SASB”) framework, and the Task Force on Climate-Related Financial Disclosures (TCFD) framework, and strive to set a high standard for safety and Employee Health & Safety (“EH&S”) goals. We expect the costs of administering our sustainability program to increase as we continue to focus and improve our sustainability initiatives and reporting.

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 owner or operator of a property, we could be held liable for the costs of removal or remediation of hazardous substances on or under the property, 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 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. In March 2023, we reported an accidental release of acrylic latex emulsion which occurred at our Bristol, Pennsylvania site, which a portion of this material ultimately flowed into a local waterway, and certain environmental claims related to this release are ongoing. In the past soil and groundwater contamination have occurred at some of the sites and might occur or be discovered at other sites. Subject to certain limitations, Dow is obligated to indemnify and hold us harmless with respect to releases of hazardous material that existed at our sites prior to the Dow Separation, however, the period for new claims at these sites has expired. Any active remedial projects on our properties which were part of the Dow Separation are being performed by Dow pursuant to its indemnification obligations. We cannot be certain that Dow will continue to fully honor their existing indemnity obligations or that the indemnity will be sufficient to satisfy all claims that we may incur. Sites acquired after the Dow Separation are subject to different limitations or may not be covered by an indemnity. We conduct comprehensive environmental due diligence for potential acquisitions to mitigate the risk of assuming obligations to conduct material levels of environmental remediation. For a more detailed description of the risks related to environmental remediation, see Item 1A—Risk Factors.

Board Oversight

The Environmental, Health, Safety, Sustainability and Public Policy Committee (the “EHSS&PP Committee”) of the Company’s Board of Directors assists the Board with oversight of Company programs, policies and initiatives that support the environment, health and safety, sustainability, corporate social responsibility and climate change. The EHSS&PP Committee is responsible for supporting alignment between the Company and the Board on the Company’s sustainability, social, and public policy goals; guiding the Company and overseeing management of risks arising from our sustainability programs, policies, partnerships, activities and goals; reviewing external public policy/governmental affairs issues and trends, and recommending Company response to these issues. The EHSS&PP Committee also reviews the Company’s annual Sustainability Report for Board approval and publication on the Company’s website.

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Government Regulation

In addition to environmental, health, and safety laws and regulations, our operations subject us to numerous federal, state, and local laws and regulations in the countries in which we operate. International trade laws and trade agreements, export and customs controls can limit the countries in which we can do business, or add significant cost to the import or export of our products or raw materials. Changes to or violations of these regulations could impact the costs of our goods or cause delay in shipments. Our products are also used in a variety of end-uses that have specific regulatory or consumer safety requirements such as those relating to food packaging or medical devices. Changes in these requirements could result in increased compliance costs, product recalls, or fines, which could prevent or inhibit the development and sale of our products. These and other laws and regulations impact the manner in which the Company conducts its business, and changes in legislation or government regulations can affect the Company’s global operations, both favorably and unfavorably. For a more detailed description of the various laws and regulations that affect the Company’s business, see Item 1A—Risk Factors.

Security

We recognize the importance of security and safety to our employees and the community. Physical security measures have been combined with process safety measures (including the use of technology) and emergency response preparedness into integrated security plans. We have conducted information security assessments at our operating facilities worldwide and identified and implemented appropriate measures to protect these facilities from physical and cyber-attacks. Effort and resources in assessing security requirements at our manufacturing facilities will continue, as required by U.S. Department of Homeland Security and other requirements.

The Company has implemented information security solutions, resources, policies, programs, and monitoring alerts to respond to potential information security events and to maintain compliance with the increasing amount of data privacy laws and regulation. Our Board of Directors provides oversight of security risks, measures and incidents, with input from members of management and our information security team. For a more information on the Company’s cyber risk management program, see Item 1C—Cybersecurity.

Human Capital Resources and Objectives

As of December 31, 2023, we had approximately 3,100 employees worldwide, with the majority (approximately 58%) located in the EMEA region (Europe, Middle East and Africa), approximately 25% in the Americas, and the remainder in Asia Pacific. Approximately 97% of our workforce is full-time.

Nearly 70% of our personnel are located at the various manufacturing sites, research and development, pilot coating, paper fabrication and testing and technology centers. The remaining employees are located at operating centers, virtual locations or geographically dispersed marketing and sales locations. Our facilities in Midland, Michigan, Bristol, Pennsylvania, and Louisville and Florence, Kentucky have union representation, while employees at certain of our other locations are represented by work councils. We believe we maintain good relations with our personnel and various labor organizations. There have been no labor strikes or work stoppages in these locations in recent history.

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People Strategy

We strive to retain a talented, diverse and inclusive workforce and understand that our success requires ongoing investment in our employees. Our approach to attracting and retaining talent is our commitment to our core values of Responsible Care®, Innovation, Respect & Integrity, Accountability & Value Creation, and Commitment to Customers. As applied to our employees, these values prioritize health and safety, accountability and rewards for achievement, and treatment of all persons in our organization with respect, honesty, and dignity.

Our core values are reflected in the goals of our “People Strategy,” which is designed to support employees through Organizational Development, Talent Management, Diversity, Equity & Inclusion and Recognition & Rewards. Organizational Development focuses on the design of organization models to achieve our business strategies, assess employee engagement, shape our culture and facilitate open communication. Talent Management measures our ability to attract and select the right talent for the right roles, onboard new employees to improve integration, build critical capabilities, and develop leaders of the future, with a culture of collaboration among high-performing and diverse teams. Diversity, Equity & Inclusion challenges us to create and maintain an environment that welcomes a broad range of

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diverse talent and facilitates and fosters a culture of inclusion. Recognition & Rewards means our efforts to manage, measure, and pay for performance; differentiate and recognize job growth with base salary increases, promotions, new assignments, annual performance awards and recognition of outstanding contributions from employees.

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Employee Health & Safety

Focus on the safety of our employees is a critical aspect of our operations. We strive towards achieving zero injuries, spills, or process safety incidents in our facilities every year. Our EH&S management system promotes a culture of rigorous investigation, corrective action, and continuous improvement applied over many years and has delivered a world-class set of internal safety policies, processes, and procedures. This system is designed to meet our objectives to continually reduce safety and environmental incidents and risks, maintain full regulatory compliance, satisfy stakeholder expectations, optimize resources, and continuously improve. We have developed a set of leading indicators to help highlight and drive improvement in Operational Safety, Process Safety, and Product Safety across the company, with effectiveness of these indicators assessed on a regular basis and modified as needed to drive improvement.

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Diversity, Equity & Inclusion

We are committed to maintaining an inclusive workforce that offers a diversity of perspectives, backgrounds and experience, and creating an environment in which all Trinseo employees have an equal opportunity to reach their potential and contribute fully to the success of the Company. Trinseo provides an equal employment opportunity, with a policy to recruit, hire, develop, and promote qualified applicants or employees without regard to race, color, religion, sex, pregnancy, gender identity, sexual orientation, veteran status, national origin, age, disability, or genetic information. We believe our commitment to diversity is reflected in our Board and executive leadership team. Thirty-three percent of our Board and thirty percent of our executive leadership team are women, and two of our Board members self-identify as a member of an underrepresented minority group. Our executive leadership team also represents broad citizenship and geographic diversity.

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Talent Management and Employee Development

We provide opportunities for career development through a combination of training, coaching, and on-the-job experiences. We believe this approach to development provides our employees with the right balance of learning options. Further, we believe that early investment in our employees ensures that our future leaders have the skills they will need to be successful within a complex and ever-changing business environment. Our annual succession planning process identifies successors for some of our most critical roles and recommends tangible developmental actions for incorporation into their long-term personal development plans. We also utilize a goal setting scorecard that enables employees to document and align their goals within a leadership team and across functions, which goals are set against annual Company priorities. Employees are evaluated on their performance versus individual goals and on the Company’s performance versus corporate goals (which includes financial and safety metrics). Part of the annual performance review process includes personal assessment goals which are tracked and reviewed throughout the year.

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Compensation Policies

Our process for determination of remuneration consists of two main components: base pay and an annual variable program, and we are committed to ensuring equitable compensation among our employees. As stated above, equal opportunity and diversity are important at Trinseo. We conduct internal reviews to assess fair treatment to determine if our pay practices are being implemented appropriately in all jurisdictions where we operate. In the United States, we also conduct internal reviews with new hires as well as an annual exam to determine the impact of ethnicity on pay decisions.

Available Information

Our annual reports on Form 10-K, quarterly reports on Form 10-Q and 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, are available free of charge through the Investor Relations section of our website, www.trinseo.com, as soon as reasonably practicable after the reports are electronically filed or furnished with the U.S. Securities and Exchange Commission (“SEC”). Copies of our board committee charters, code of conduct, corporate governance guidelines and

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other corporate governance information are also available on our website. See Part III–Item 10–Code of Ethics. We provide this website and the information contained in or connected to it for informational purposes only. This information is not included in, or incorporated by reference to, this Annual Report.

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Risks Related to Our Operations

We are subject to risks associated with our strategy to transform to a specialty materials and sustainable solutions provider.

We have taken steps toward executing on our strategy to transform the Company to a specialty materials and sustainable solutions provider, including the PMMA Acquisition, Aristech Surfaces Acquisition and the sale of our synthetic rubber business. We continue to explore strategic alternatives related to our styrenics business, which may include the marketing of individual assets and regional businesses, which divestiture remains an important part of our transformation strategy. We plan to continue to prioritize investments in higher growth, higher margin and lower earnings volatility areas such as Engineered Materials and CASE applications, products containing recycled materials, and to deemphasize the more volatile, lower growth assets in our portfolio.

The implementation of our transformation strategy has resulted in, and may continue to result in, changes to our business, operations, capital allocation, operational and organizational structure, increased demands on management, and could result in short-term and one-time costs, including higher than expected restructuring costs, loss of revenue, and other negative impacts on our business. We cannot guarantee that the execution of this strategy, including the steps taken to date, will lead to higher growth, higher margins and lower earnings volatility. We also cannot be certain that we will be successful in identifying opportunities for divestiture of our styrenics business or identifying investments in assets we believe best fit our portfolio transformation, whether such opportunities will be available at a price and at terms acceptable to us, or at all, or whether we will face difficulties due to timing or funding availability. Implementation of this transformation may take longer than anticipated, and once implemented, we may not realize, in full or in part, the anticipated benefits or such benefits may be realized more slowly than anticipated. The failure to realize benefits, which may be due to our inability to execute, delays in implementation, global or local economic conditions, accessibility to capital markets, inflation, high interest rates, competition, and the other risks described herein, could have a material adverse effect on our business, prospects, financial condition, results of operations, cash flows, as well as the trading price of our securities.

We may be unable to achieve cost savings and other benefits from our restructuring activities and cost reduction initiatives.

Since 2022 we have announced certain restructuring programs associated with our strategic transformation, adoption of cost reduction actions designed to improve profitability.

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In December 2022, we announced approval of an asset restructuring plan designed to reduce costs, improve profitability, and reduce exposure to cyclical markets and elevated natural gas prices, which includes (i) closure of manufacturing operations at our styrene production facility in Boehlen, Germany, (ii) closure of one of our production lines at our Stade, Germany polycarbonate plant, (iii) closure of our PMMA sheet manufacturing site in Matamoros, Mexico and (iv) reduction of SB latex capacity at our Hamina, Finland plant. In August 2023 we announced a restructuring plan designed to optimize our PMMA sheet network, primarily in Europe, and consolidate manufacturing operations, which included closure of certain plants and product lines, including (i) closure of manufacturing operations at our PMMA cast sheets plant in Bronderslev, Denmark, (ii) closure of manufacturing operations at our batch polyester tray casting plant in Belen, New Mexico, and (iii) closure of our PMMA extruded sheet production line at our Rho, Italy plant. The Plan also included certain other workforce reductions, including elimination of certain executive positions, to streamline the Company’s internal general & administrative network. Finally, we also closed our Terneuzen, the Netherlands styrene plant in November 2023. With this closure, we no longer produce styrene, and will purchase all of our styrene needs from third parties.

We believe these actions will reduce production risk, reduce ongoing capital expenditures and turnaround costs, as well as lower our carbon footprint. We believe these actions will not only increase our profitability and cash generation but will also enable us to continue investing in transformation projects such as recycling and material substitution innovations, which offer significant growth potential even in the current market environment.

Our efforts to achieve these improvements and efficiencies may not be successful or generate expected cost savings, and we may incur greater costs than currently anticipated to implement and achieve these initiatives, which could have an adverse impact on our financial condition or results of operations. We cannot guarantee that these initiatives will successfully generate the expected cost savings or will not require additional expenditures beyond our initial estimates. The actual timing and costs of this asset restructuring may differ from our expectations and estimates, and such differences may be material.

Volatility in the cost of raw materials, disruption in the supply of raw materials, may adversely affect our financial condition and results of operations or cause our financial results to differ materially from our forecasts.

Our results of operations can be directly affected, positively and negatively, by volatility in the cost of our raw materials, which are subject to global supply and demand and other factors beyond our control. Our principal raw materials (butadiene, BPA, MMA, and styrene) together represent approximately 31% of our total cost of goods sold. Crude oil prices also impact our raw material and energy costs. Generally, higher crude oil prices lead to higher costs of natural gas and raw materials, although some raw materials are impacted less than others. Volatility in the cost of energy or raw materials makes it more challenging to manage pricing and pass the increases on to our customers in a timely manner. We believe that rapid changes in pricing also can affect the volume our customers consume. As a result, our gross profit and margins could also be adversely affected and our financial results may differ materially from our forecasts.

We have supply agreements with Dow for butadiene, and MMA, which are critical raw materials to our business. These raw materials and other less critical materials amount to approximately 21% of our total raw materials acquired in 2023, based on aggregate purchase price. The remainder is purchased via other third-party suppliers on a global basis. As these and other third-party supply agreements expire, we may be unable to renegotiate or renew these contracts, or obtain new long-term supply agreements on terms comparable to us, or at all, which may significantly impact our operations. See Item 1—Business— Sources and Availability of Raw Materials.

If the availability of any of our principal raw materials is limited, we may be unable to produce some of our products in the quantities demanded by our customers, which could have an adverse effect on plant utilization and our sales of products requiring such raw materials. Suppliers may have temporary limitations preventing them from meeting our requirements, and we may not be able to obtain substitute alternative suppliers in a timely manner.

Increased energy costs, shipping costs and supply constraints, including as a result of ongoing global conflicts, could adversely impact our results of operations.

We use natural gas and electricity to operate our facilities and generate heat and steam for our various manufacturing processes, and these operations can be directly affected by volatility in the cost and availability of energy, which is often subject to factors outside of our control. The ongoing war between Russia and Ukraine has impacted

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global energy markets, particularly in Europe, leading to high volatility and increased prices for natural gas and other energy supplies. Reductions in the supply of natural gas from Russia to Europe led to supply shortages in Europe which may continue for the foreseeable future. Continued natural gas supply shortages, or a shutdown of natural gas supply from Russia, could lead to additional price increases, energy supply rationing, or temporary reduction in operations or closure of our European manufacturing plants, which could have a material adverse impact on our business or results of operations.

In the past we have entered into certain commodity swap agreements to protect against fluctuations in energy prices, including natural gas, some of which have generated losses when prices stabilized. We may continue to enter into commodity swaps, forward contracts, or options from time to time. Our hedges against energy price volatility could adversely impact our results of operations.

Global conflicts may also impact our shipping and transportation costs, and delay shipments of our products to our customers or shipments of raw materials to our manufacturing sites. The impact of the ongoing Israel-Hamas war and the threat of a broader conflict in the Middle East may disrupt shipping lanes in the Red Sea and elsewhere, delay shipments in the region, and raise prices for shipping regionally as well as globally, which could have a material adverse impact on our results of operations. A potential broader conflict could augment these negative impacts.

Deterioration of our credit profile could limit our access to commercial credit.

Maintaining our credit profile is important to our cost and availability of capital, including our access to commercial credit. Third parties determine our credit profile based on a number of factors, including our credit ratings set by independent credit rating agencies, earnings and financial strength, as well as our strategies, operations, and execution of announced actions. Changes to our credit profile could materially impact our credit capacity or restrict our ability to access commercial credit.

Chemical manufacturing is inherently hazardous and production at our manufacturing facilities could be disrupted for a variety of reasons. Disruptions could expose us to significant losses or liabilities.

There are hazards and risks of disruption inherent in chemical manufacturing and the related storage and transportation of raw materials, products and wastes which exist in our operations and the operations of other occupants with whom we share manufacturing sites. These potential risks of disruption include, but are not necessarily limited to:

These hazards could expose employees, customers, the community and others to toxic chemicals and other hazards, contaminate the environment, damage property, result in personal injury or death, lead to an interruption or suspension of operations, damage our reputation and adversely affect the productivity and profitability of a particular manufacturing facility or us as a whole, and result in the need for remediation, governmental enforcement, regulatory shutdowns, the imposition of government fines and penalties, and claims brought by governmental entities or third parties. Legal claims and regulatory actions could subject us to both civil and criminal penalties, which could affect our product sales, reputation and profitability. Liabilities associated with the investigation and cleanup of hazardous substances, as well as personal injury, property damage or environmental damages arising from the release of, or exposure to, such hazardous substances, may be imposed in many situations without regard to violations of laws or regulations or other fault. These liabilities may be material and can be difficult to identify or quantify.

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In March 2023, due to an equipment failure at the Bristol, Pennsylvania facility, operated by our wholly-owned subsidiary, Altuglas LLC, an accidental release of latex emulsion product occurred, which ultimately flowed into a local waterway (the “Bristol Spill”). We reported the event and cooperated closely with local, state, and federal authorities. The Company has been named, and continues to defend against, claims related to the Bristol Spill. See Item 3—Legal Proceedings.

We are dependent upon the continued safe and reliable operation of our production facilities to minimize risks associated with our manufacturing processes, but we cannot completely eliminate the risk of accidental contamination, discharge or injury resulting from these materials. We have been in the past, and may be in the future, subject to claims relating to exposure to hazardous materials, and have had, from time to time in the past, incidents that have temporarily shut down or otherwise disrupted our manufacturing, causing production delays and resulting in liability for workplace injuries, environmental remediation, regulatory penalties or other claims. Systems in place to manage environmental, health and safety compliance, and our emergency response and crisis management plans may not address or foresee all potential risks or causes of disruption, or sufficiently address the impacts of such incidents on our employees, customers or the communities in which our plants reside. We cannot assure you that we will not experience these types of incidents in the future or that these incidents will not result in production delays or otherwise have a material adverse effect on our business, reputation, financial condition or results of operations.

If disruptions occur, alternative facilities with sufficient capacity or capabilities may not be available, may cost substantially more or may take a significant time to start production. Each of these scenarios could negatively affect our business and financial performance. If one of our key manufacturing facilities is unable to produce our products for an extended period of time, our sales may be reduced by the shortfall caused by the disruption and we may not be able to meet our customers’ needs, which could cause them to seek other suppliers. Furthermore, to the extent a production disruption occurs at a manufacturing facility that has been operating at or near full capacity, the resulting shortage of our product could be particularly harmful because production at the manufacturing facility may not be able to reach levels achieved prior to the disruption. Our insurance policies may not fully insure against all potential causes of disruption due to limitations and exclusions in those policies. Therefore, incidents that significantly disrupt our operations may expose us to significant losses and/or liabilities.

If we are unable to execute on our capital projects or growth plans within their expected budget and timelines, or if the market conditions assumed in our projections deteriorate, our business, financial condition, results of operations and cash flows could be materially and adversely affected.

Capital projects and other growth investments may have lengthy deadlines during which market conditions may deteriorate between the capital expenditure’s approval date and the conclusion of the project, negatively impacting projected returns. Cost-saving measures, capital allocation priorities and elevated borrowing costs may impact our decision whether to undertake or delay the start of certain capital projects in the near future. Delays or cost increases related to capital and other spending programs involving engineering, procurement and construction of facilities or manufacturing lines or the development of new technologies could materially adversely affect our ability to achieve forecasted operating results. Project delays or budget overages may arise as a result of unpredictable events, which may be beyond our control, including, but not limited to:

Furthermore, presumed demand for the technologies or products provided by the manufacturing facilities or lines being constructed or the technologies being developed may deteriorate during the project period. If we were unable to stay within a project’s overall timeline or budget, or if market conditions change, it could materially and adversely affect our business, financial condition, results of operations and cash flows.

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If we are not able to continue the technological innovation and successful commercial introduction of new products, our customers may turn to other producers to meet their requirements.

Our industry and the end markets into which we sell our products experience periodic technological changes and ongoing product improvements. Our customers may introduce new generations of their own products or require new technological and increased performance specifications that would require us to develop customized products. Our future growth will depend on our ability to predict and react to changes in key end markets, and to successfully develop, manufacture and market products in such changing end markets. We need to continue to identify, develop and market innovative products on a timely basis to replace existing products in order to maintain our profit margins and our competitive position. We may not be successful in developing new products and technology that successfully compete with these materials, and our customers may not accept any of our new products. If we fail to keep pace with evolving technological innovations or fail to modify our products in response to our customers’ needs, then our business, financial condition and results of operations could be adversely affected as a result of reduced sales of our products.

Risks Related to Acquisitions and Dispositions

We may not be successful in the proposed divestiture of our styrenics businesses.

We continue to explore strategic alternatives related to our styrenics business. While the divestiture of our styrenics businesses remains a key part of our transformation strategy, we cannot estimate whether economic conditions and capital markets will sufficiently improve to allow us to successfully complete a sale of all or a portion of our styrenics business, locate an adequate buyer or buyers, or negotiate terms of a sale acceptable to the Company.

A successful divestiture depends on various factors, including our ability to effectively transfer liabilities, contracts, facilities and employees to any purchaser, revise our legal entity structure, negotiate continued equity ownership, identify and separate intellectual property, reduce fixed costs previously associated with the divested assets or business, and collect the proceeds from any sale. Any divestiture may result in a dilutive impact to our future earnings if we are unable to offset the dilutive impacts from the loss of revenue associated with the divested business, as well as significant write-offs, including those related to long-lived assets, including goodwill and other intangible assets, which could have a material adverse effect on our results of operations and financial condition. All of these efforts require varying levels of management resources, which may divert our attention from other business operations.

We may fail to realize the anticipated benefits of acquisitions or such benefits may take longer to realize than expected, and we may encounter difficulty integrating these businesses into our operations. We may also be required to incur impairment and other charges, which would adversely affect our operating results.

Our ability to realize the anticipated benefits of acquisitions will depend on our ability to successfully integrate the underlying businesses into ours. The Company has devoted significant attention and resources integrating the operations, systems, processes and procedures of the acquired businesses, and we expect to continue to do so. If we fail to effectively integrate, we could lose or diminish the expected benefits of these acquisitions. Further, this integration may not result in the realization of the cost and revenue synergies and benefits that we expected at the time of the acquisitions, nor can we give assurances that these benefits will be achieved when expected or at all.

We also face risks that we fail to meet our financial and strategic goals, due to, among other things, inability to grow the acquired business, achieve expected margins and grow relationships with customers. We may also be adversely affected by other economic, business, and/or competitive factors which did not exist at the time of closing. Such conditions could materially adversely impact our business and results of operations.

We may engage in other future strategic disposition or acquisitions of certain assets and/or businesses that could affect our business, results of operations, financial condition and liquidity.

We may selectively pursue collaboration agreements, joint ventures or complimentary acquisitions which inherently involves a number of risks and presents financial, managerial and operational challenges, including, but not limited to:

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Also, the presence of one or more material liabilities of an acquired company that are unknown to us at the time of acquisition may have a material adverse effect on our business or financial results. Our acquisition and joint venture strategy may not be successfully received by customers or other stakeholders, and we may not realize any anticipated benefits from these other acquisitions or joint ventures.

We may also opportunistically pursue dispositions of certain other assets and/or businesses, which may involve material amounts of assets or lines of business, and adversely affect our results of operations, financial condition and liquidity. If any such dispositions were to occur, under the terms of our senior secured credit agreement (the “Credit Agreement”) governing our senior secured financing facility of up to $1,075.0 million (the “Senior Credit Facility”), the credit agreement (the “2028 Refinance Credit Agreement”) governing our senior secured term loan facility of $1,077.3 million maturing in May 2028 (the “2028 Refinance Credit Facility”), and the indentures (the “Indentures”) governing our 5.375% senior notes due 2025 (the “2025 Senior Notes”), and our 5.125% senior notes due 2029 (the “2029 Senior Notes”), we may be required to apply the proceeds of the sale to repay any borrowings under our Senior Credit Facility, 2028 Refinance Credit Facility, and our 2025 Senior Notes or our 2029 Senior Notes. Dispositions may also involve continued financial involvement in the divested business, such as through continuing equity ownership, transition service agreements, supply agreements, guarantees, indemnities or other current or contingent financial obligations.

Joint ventures may not operate according to their business plans if we or our partners fail to fulfill our or their obligations, or differences in views among our joint venture partners result in delayed decisions, which may adversely affect our results of operations and may force us to dedicate additional resources to these joint ventures.

For the year ended December 31, 2023, we received dividends of $65.0 million from our Americas Styrenics joint venture. We may enter into additional joint ventures in the future. The nature of a joint venture requires us to share control with unaffiliated third parties. If joint venture partners do not fulfill their obligations, the affected joint venture may not be able to operate according to its business plan. In that case, our results of operations may be adversely affected and we may be required to increase the level of our commitment to the joint venture. Differences in views among joint venture participants and our inability to unilaterally implement sales and production strategies or determine cash distributions from joint ventures may significantly impact short-term and longer-term financial results, financial condition and the value of our ordinary shares.

Risks Related to Regulation and Compliance

We are subject to customs, international trade, export control, and antitrust laws that could require us to modify our current business practices and incur increased costs.

We are subject to numerous regulations, including customs and international trade laws, export/import control laws, and associated regulations. These laws and regulations limit the countries in which we can do business; the persons or entities with whom we can do business; the products which we can buy or sell; and the terms under which we can do business, including anti-dumping restrictions. In addition, we are subject to antitrust laws and zoning and occupancy laws that regulate manufacturers generally and/or govern the importation, promotion and sale of our products, the operation of factories and warehouse facilities and our relationship with our customers, suppliers and competitors. If any of these laws or regulations were to change or were violated by our management, employees, suppliers, buying agents or trading companies, the costs of certain goods could increase, or we could experience delays in shipments of our goods, be subject to fines or penalties, or suffer reputational harm, which could reduce demand for our products and hurt our business and negatively impact results of operations. In addition, in some areas we benefit from certain trade protections, including anti-dumping protection and the EU’s Authorized Economic Operator program, which provides expedited customs treatment for materials crossing national borders. If we were to lose these protections, our results of operations could be adversely affected.

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Global trade conflicts and the imposition of tariffs may have a material adverse impact on our business and results of operations.

Various governments have adopted new approaches to their trade policies seeking to renegotiate, or potentially terminate, certain existing bilateral or multi-lateral trade agreements and implement new tariff schedules. For example, the U.S. and China maintain certain trade policies and tariffs on imported products, which have resulted in shifting trade flows and increased costs for raw materials and finished goods. Uncertainty over global tariffs has and may continue to delay purchasing decisions by our customers as they assess the impact of such trade policies on their business. Further changes in trade policy, trade restrictions, tariffs, or other governmental action has the potential to adversely impact demand for our products or our customers’ products, and our costs, including prices of raw materials, which in turn could adversely impact our business, financial condition and results of operations.

We could be subject to changes in the global and local tax regulatory environments in the jurisdictions in which we operate, which could adversely impact our results of operations.

We are subject to income taxes in Ireland, the United States, and numerous other foreign jurisdictions where our subsidiaries are organized. Due to economic and political conditions, tax rates in these jurisdictions may change significantly. Our effective tax rate in the future can be impacted by changes in the mix of earnings in countries with different statutory tax rates, changes in the valuation of deferred tax assets and liabilities, changes in tax laws or their interpretations, and other administrative or judicial rulings. Our tax returns are subject to examination by local tax authorities and other governmental bodies. We regularly assess the probability of an adverse outcome resulting from these examinations when determining our provision for income taxes. There is an inherent uncertainty to the outcome of these examinations. If it is determined that the taxes we owe are in excess of amounts previously accrued, our operating results and cash flows could be adversely affected.

Multi-jurisdictional changes enacted in response to the action items provided by the Organization for Economic Co-operation and Development (OECD), including the OECD's Global Anti-Base Erosion ("GloBE”) rules under Pillar Two, which will introduce a global minimum corporate tax rate set at 15% on multinational enterprises, increases tax uncertainty and may impact the Company’s effective tax rate and provision for income taxes. Given the unpredictability of possible further changes and the potential interdependency of global tax laws and regulations, it is difficult to predict the cumulative effect of such tax laws and regulations on Company’s results of operations.

Regulatory and statutory changes, including those related to climate change and sustainability, applicable to our raw materials and products or our customers’ products, or changes to consumer preferences or public perception, could require material expenditures, changes in our operations and could adversely affect our financial condition and results of operations.

Changes in environmental, health and safety regulations in jurisdictions where we manufacture and sell our products could lead to a decrease in demand for our products. In addition to changes in regulations, customers, investors and other stakeholders are increasingly focusing on environmental issues and disclosures, including climate change, energy and water use, greenhouse gas emissions and other sustainability concerns. Change in public sentiment may result in changing demands for our products or could cause changes in the market dynamics of our existing products, impacting pricing, or cause us to incur additional costs to make changes to our operations to comply with such demand changes. Compliance with new regulations could increase the costs incurred to manufacture our products, or costs incurred by our customers to use our products and otherwise limit the use of these products and lead to decreased demand which would have an adverse effect on our business and results of operations. Our inability to meet investor, industry or stakeholder sustainability goals could materially impact our financial condition and results of operations.

Materials such as acrylonitrile, ethylbenzene, styrene, butadiene, bisphenol-A (“BPA”), methyl methacrylate (“MMA”), UV-stabilizers, and halogenated flame retardant and others are used in the manufacturing of our products and have come under scrutiny due to potentially significant or perceived health and safety concerns. In addition, per- and polyfluoroalkyl substances (“PFAS”), chemicals used in products which require anti-dripping, temperature, chemicals, or fire resistance properties, are under heightened governmental and regulatory scrutiny in the U.S., Europe and other countries for potential contamination of soil, air and water, specifically in drinking water. The hazard classification of our products, or materials in our products, could change due to new data or toxicology studies, which may make sales of such products difficult to certain customers or in certain markets if we are unable to manufacture products without such classified materials. Heightened regulatory scrutiny, consumer protection actions or customer disapproval of these types

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of materials could lead to regulatory action or declining sales, and could adversely affect our results of operations and financial condition.

Moreover, bans on single-use plastic, restrictions on microplastics and similar regulatory actions to reduce plastic waste and influence consumer preferences for sustainable and recyclable materials may reduce the demand for some of our products over time. New or proposed legislation addressing the global challenge of plastic waste may place responsibility on producers and sellers to include recycled content in their products. This legislation may impact our sales and place more importance on our initiatives to further develop technologies for recycled products.

Additionally, these regulatory regimes currently require significant compliance expenditures and future regulatory changes applicable to our raw materials and products or our customers’ products, could require significant additional expenditures or changes in our operations. Governmental inquiries or lawsuits involving these chemicals could lead us to incur liability for damages or other costs, lead to civil proceedings, the imposition of fines and penalties, or other remedies, and potentially add costs or restrictions to our manufacturing operations in the future.

Our products are also used in a variety of end-uses that have specific regulatory requirements such as those relating to products that have contact with food or medical device end-uses. Our customers or distributors may not follow our policies and advice regarding the safe use and application of our products, which may unknowingly expose us to third-party claims. We and many of the applications for the products in the end markets in which we sell our products are regulated by various national and local rules, laws and regulations, such as the U.S. Toxic Substances Control Act and the EU’s Registration, Evaluation, Authorisation and Restriction of Chemicals regulations. An increasing number of countries continue to adopt similar requirements, which could require significant compliance expenditures or changes to our sales and marketing strategies and operations. Changes to existing regulations could result in additional compliance costs, seizures, confiscations, recall or monetary fines, any of which could prevent or inhibit the development, distribution and sale of our products. Changes in environmental and safety laws and regulations banning or restricting the use of these residual materials in our products, or our customers’ products, could adversely affect our results of operations and financial condition. Failure to appropriately manage safety, human health, product liability and environmental risks associated with our products, product life cycles and production processes could adversely impact employees, communities, stakeholders, our reputation and the results of our operations.

Compliance with extensive and evolving environmental, health and safety laws may require substantial expenditures.

We use large quantities of hazardous substances, generate hazardous wastes and emit wastewater and air pollutants in our manufacturing operations. Consequently, our operations are subject to extensive environmental, health and safety laws and regulations at both the national and local level in multiple jurisdictions. Many of these laws and regulations have become more stringent over time and the costs of compliance with these requirements may continue to increase, including costs associated with any capital investments for pollution control facilities. In addition, our production facilities and operations require operating permits, licenses or other approvals that may be subject to periodic renewal and, in circumstances of noncompliance, may be subject to revocation. The necessary licenses, permits or other approvals may not be issued or continue in effect, and any issued licenses, permits or approvals may contain more stringent limitations that restrict our operations or that require further expenditures to meet the permit requirements.

This continuing focus on climate change in jurisdictions in which we operate has and will continue to result in new environmental regulations that may require us to incur additional costs in complying with new regulatory and customer requirements, which may adversely impact our operations and financial condition. Compliance with more stringent environmental requirements would likely increase our costs of transportation and storage of raw materials and finished products, as well as the costs of storage and disposal of wastes. Additionally, we may incur substantial costs, including penalties, fines, damages, criminal or civil sanctions and remediation costs for the failure to comply with these laws or permit requirements.

We may be subject to losses due to liabilities or lawsuits related to contaminated land we own or operate or arising out of environmental damage or personal injuries associated with exposure to chemicals or the release of chemicals.

Under the Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA”) and similar statutes outside the U.S., the current or former owner or operator of a property contaminated by hazardous substance

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releases is subject to strict, unlimited, joint, several and retroactive liability for the investigation and remediation of the property, and also may be liable for natural resource damages associated with the releases. In addition to potential statutory liability, we also face the risk that individuals could seek damages for personal injury due to exposure to chemicals at our facilities, chemicals which have been released from our facilities, chemicals otherwise owned or controlled by us, or chemicals which allegedly migrated from products containing our materials. For example, we face class action claims and regulatory action by various government agencies related to the Bristol Spill, which are ongoing. See Item 3—Legal Proceedings. We may be subject to claims with respect to workplace exposure, workers’ compensation and other health and safety matters. Legal claims and regulatory actions could subject us to both civil and criminal penalties, which could affect our reputation as well as our results of operations, financial condition, and liquidity.

There are several properties which we own on which Dow has been conducting remediation to address historical contamination, while there are other properties with historical contamination that are owned by Dow that we lease for our operations. While we did not assume the liabilities associated with these properties in the U.S., because CERCLA and similar laws can impose liability for contamination on the current owner or operator of a property, even if it did not create the contamination, there is a possibility that a governmental authority or private party could seek to include us in an action or claim for remediation or damages, even though the contamination may have occurred prior to our ownership or occupancy. While Dow has agreed to indemnify us for liability for releases of hazardous materials that occurred prior to our separation from Dow, the indemnity is subject to monetary and temporal limitations. The period for new claims at these sites has expired. Sites acquired after the Dow Separation are subject to a different limitations period, or may not be subject to any indemnification. We cannot be certain that Dow will fully honor the indemnity or that the indemnity will be sufficient to satisfy all claims that we may incur. Any active remedial projects on our properties which were part of the Dow Separation are being performed by Dow pursuant to its indemnification obligations. In addition, we face the risk that future claims might fall partially or fully outside of the scope of the indemnity, particularly if there is a release of hazardous materials that occurs in the future or at any time after our separation from Dow or if the condition requiring remediation is attributable to a combination of events or operations occurring prior to and after our separation from Dow. The Company believes it has set adequate reserves for all remediation projects it is currently undertaking.

Risks Related to Our Indebtedness

Our current and future level of indebtedness of our subsidiaries could adversely affect our financial condition.

As of December 31, 2023, our indebtedness totaled approximately $2.3 billion. Additionally, as of December 31, 2023, we had $98.4 million (net of $24.1 million outstanding letters of credit) of funds available for borrowing under our senior secured credit agreement (the “Credit Agreement”) governing our senior secured financing facility of up to $1,075.0 million (the “Senior Credit Facility”), as well as $113.5 million of funds available for borrowing under our accounts receivable securitization facility.

Our current level of indebtedness, as well as future borrowings or other indebtedness, could have significant consequences for our business, including but not limited to:

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Although the terms of our Credit Agreement, the credit agreement (the “2028 Refinance Credit Agreement”) governing our senior secured term loan facility of $1,077.3 million maturing in May 2028 (the “2028 Refinance Credit Facility”), and the indentures (the “Indentures”) governing our 5.375% senior notes due 2025 (the “2025 Senior Notes”), and our 5.125% senior notes due 2029 (the “2029 Senior Notes”) contain restrictions on the incurrence of additional indebtedness, these restrictions are subject to a number of qualifications and exceptions and the indebtedness incurred in compliance with these restrictions could be substantial. Also, we are not prevented from incurring obligations that do not constitute “indebtedness” as defined in the related agreements such as operating leases and trade payables. If new debt is added to our subsidiaries’ current debt levels, the risks related to indebtedness that we now face could intensify.

In addition, a substantial portion of our subsidiaries’ current indebtedness is secured by substantially all of our assets, which may make it more difficult to secure additional borrowings at reasonable costs. If we default or declare bankruptcy, after these obligations are met, there may not be sufficient funds or assets to satisfy our subordinate interests, including those of our shareholders.

For more information regarding our indebtedness, see Item 7—Management’s Discussion and Analysis of Financial Conditions and Results of Operations— Capital Resources, Indebtedness and Liquidity.

The terms of our subsidiaries’ indebtedness may restrict our current and future operations, particularly our ability to respond to change or to take certain actions.

Our credit, debt and refinance agreements contain a number of covenants imposing certain restrictions on our subsidiaries’ businesses. These restrictions may affect our ability to operate our business and may limit our ability to take advantage of business opportunities. These agreements restrict, among other things, our subsidiaries’ ability to:

Our Senior Credit Facility contains a springing covenant which, if not met, limits our borrowing to 30% of the maximum available capacity under the revolver. We have not been in compliance with this financial covenant since March 31, 2023 and access to our revolving credit facility has been limited to 30% of the total capacity of the revolver. We are also required to meet a minimum liquidity test under our 2028 Refinance Credit Agreement. The ability of our subsidiaries to comply with the covenants, financial ratios and tests contained in the Credit Agreement, the 2028 Refinance Credit Agreement and the Indentures, to pay interest on indebtedness, fund working capital, and make anticipated capital expenditures depends on our future performance, which is subject to general economic conditions and other factors, some of which are beyond our control. There can be no assurance that our business will generate sufficient cash flow from operations or that future borrowings will be available under our Senior Credit Facility to fund liquidity needs in an amount sufficient to enable them to service their indebtedness. Furthermore, if we need additional capital for general corporate purposes or to execute on an expansion strategy, there can be no assurance that this capital will be available on satisfactory terms or at all.

A failure to repay amounts owed under the Senior Credit Facility, 2028 Refinance Credit Facility, our 2029 Senior Notes or 2025 Senior Notes at maturity would result in a default. In addition, a breach of any of the covenants in the Credit Agreement, 2028 Refinance Credit Agreement or Indentures, or our inability to comply with the required financial ratios, tests or limits could result in a default. If a default occurs, lenders may refuse to lend us additional funds and the lenders or noteholders could declare all of the debt and any accrued interest and fees immediately due and payable. A default under one of our subsidiaries’ debt agreements may trigger a cross-default under our other debt agreements. For more information regarding our indebtedness, please see Item 7—Management’s Discussion and Analysis of Financial Conditions and Results of Operations— Capital Resources, Indebtedness and Liquidity.

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Risks Related to Litigation

We are party to certain legal proceedings, and may be subject to additional litigation, arbitration or legal proceedings in the future.

From time to time, we may be involved in litigation, arbitration or other legal proceedings relating to claims arising out of our operations, business, including but not limited to disputes over prior transactions or service or maintenance costs at sites we do not own. The results of any current or future legal proceedings cannot be predicted with certainty and, regardless of the outcome, we may incur significant costs and experience a diversion of management resources as a result of such proceedings. The results of any such proceedings could have a material adverse impact on our business, financial condition, cash flows and results of operations.

The Company records accruals for legal matters which are both probable and reasonably estimable, and the Company believes that it has adequately accrued for ongoing legal matters as appropriate. Litigation and arbitration are inherently unpredictable and, although the Company believes that its accruals are adequate and/or that it has valid defenses in such matters, unfavorable resolutions could occur that are in excess of amounts accrued or which could have a material adverse effect on the Company’s financial condition, results of operations or cash flows.

Risks Related to Our Relationship with Dow

Dow provides significant operating and other services, and certain raw materials used in the production of our products, under agreements that are important to our business. The failure of Dow to perform its obligations, or the termination of these agreements, could adversely affect our operations.

Prior to the Dow Separation, we were operated by Dow, which has provided and continues to provide services under certain agreements that are important to our business. We are a party to (i) SAR SSAs,; (ii) supply and sales agreements; and (iii) the AR MOD5 Agreement. Under the terms of the above agreements, either party is also permitted to terminate the applicable agreement in a variety of situations, including in the event of the other party’s uncured material breach, insolvency, change of control or cessation of operations. Should Dow fail to provide these services or raw materials, or should any of the above agreements be terminated, we would be forced to obtain these services and raw materials from third parties or provide them ourselves. Additionally, if Dow terminates agreements pursuant to which we are obligated to provide certain services, we may lose the fees received by us under these agreements. The failure of Dow to perform its obligations under, or our inability to renegotiate, renew or replace any of these contracts, particularly without an alternative source of raw materials, could adversely affect our operations. Depending on market conditions at the time of any such termination, we may not be able to enter into substitute arrangements in a timely manner. For more information regarding our relationship with Dow, please see Item 1—Business — Our Relationship with Dow.

We are party to certain license agreements with Dow relating to intellectual property that is essential to our business. Because of this relationship, we may have limited ability to expand our use of certain intellectual property beyond the field of the license or to police infringement that may be harmful to our business.

In connection with the Dow Separation, we acquired ownership of, or in some cases, a worldwide right and license to use, certain patents, patent applications and other intellectual property of Dow that were used by Dow to operate our business segments or held by Dow primarily for the benefit of our business segments, prior to the Dow Separation. Generally, we acquired ownership of the intellectual property that was primarily used in our business segments and acquired a license to a more limited set of intellectual property that had broader application within Dow beyond our core business segments. Our license from Dow is perpetual, irrevocable, fully paid, and royalty-free. Furthermore, our license from Dow is exclusive within our business segments for certain patents and patent applications that were used by Dow primarily prior to our separation, subject to licenses previously granted by Dow, and to certain retained rights of Dow, including Dow’s retained right to use patents and patent applications outside of our business segments and for internal consumption by Dow. Our license from Dow relates to polymeric compositions, manufacturing processes and end applications for the polymeric compositions; and is limited to use in defined areas corresponding to our current business segments excluding certain products and end-use application technology retained by Dow. Our ability to develop, manufacture or sell products and technology outside of these defined areas may be impeded by the intellectual property rights that have been retained by Dow, which could adversely affect our business, financial condition and results of operations. Additionally, infringement on these intellectual property rights could also impact our business and

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competitive position. We may not be able to enforce our rights, and Dow may be unwilling to enforce its rights, with respect to this intellectual property that has been licensed by Dow.

Risks Related to Our Intellectual Property

Our business relies on intellectual property and other proprietary information and our failure to adequately protect or effectively enforce our rights could harm our competitive advantages with respect to the manufacturing of some of our products.

Our success depends to a significant degree upon our ability to protect, preserve and enforce our intellectual property rights, including patents, trademarks, licenses, trade secrets and other proprietary information of our business. However, we may be unable to prevent third parties from using our intellectual property and other proprietary information without our authorization or independently developing intellectual property and other proprietary information that is similar to or competes with ours. Any inability by us to effectively prevent the unauthorized use of our intellectual property and other proprietary information by others could reduce or eliminate any competitive advantage we have developed, cause us to lose sales or otherwise harm our business or goodwill. If it becomes necessary for us to initiate litigation to protect our proprietary rights, any proceedings could be burdensome and costly, and we may not prevail.

We may be unable to determine when third parties are using our intellectual property rights without our authorization, particularly our manufacturing processes. In addition, we cannot be certain that any intellectual property rights that we have licensed to third parties are being used only as authorized by the applicable license agreement. The undetected, unremedied, or unauthorized use of our intellectual property rights or the legitimate development or acquisition of intellectual property that is similar to or competes with ours by third parties could reduce or eliminate the competitive advantage we have as a result of our intellectual property, adversely affecting our financial condition and results of operations.

If we fail to adequately protect our intellectual property and other proprietary information, including our processes, apparatuses, technology, trade secrets, trade names and proprietary manufacturing know how, methods and compounds, through obtaining patent protection, securing trademark registrations and securing our trade secrets through the use of confidentiality agreements of appropriate scope and other means, our competitive advantages over other producers could be materially adversely affected. If we determine to take legal action to protect, defend or enforce our intellectual property rights, any suits or proceedings could result in significant costs and diversion of our resources and our management’s attention. We may not prevail in any such suits or proceedings. A failure to protect, defend or enforce our intellectual property rights could have an adverse effect on our financial condition and results of operations.

Our products may infringe the intellectual property rights of others, which may cause us to incur unexpected costs or prevent us from selling our products.

Many of our competitors have a substantial amount of intellectual property that we must continually strive to avoid infringing as we improve our own business processes and develop new products and applications. Although it is our policy and intention not to infringe valid patents of which we are aware, we cannot provide assurances that our processes and products and other activities do not and will not infringe issued patents (whether present or future) or other intellectual property rights belonging to others. There nonetheless could be third-party patents that cover our products, processes or technologies, and it is possible that we could be liable for infringement of such patents and could be required to take remedial or curative actions to continue our manufacturing and sales activities with respect to one or more products that are found to be infringing. We may also be subject to indemnity claims by our business partners arising out of claims of their alleged infringement of the patents, trademarks and other intellectual property rights of third parties in connection with their use of our products. Intellectual property litigation often is expensive and time-consuming, regardless of the merits of any claim, and our involvement in such litigation could divert our management’s attention from operating our business. If we were to discover that any of our processes, technologies or products infringe on the valid intellectual property rights of others, we may not be able to obtain the necessary licenses on acceptable terms, or at all, or be able to modify our processes or technologies or re-engineer our products in a manner that is successful in avoiding infringement. Moreover, if we are sued for infringement and lose, we could be required to pay substantial damages and/or be enjoined from using or selling the infringing products or technology. Any of the foregoing could cause us to incur significant costs and prevent us from selling our products and could have an adverse effect on our financial condition and results of operations.

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Risks Related to Data Security

Data security breaches could compromise sensitive information related to our business or the private information of our employees, vendors, and customers, which could adversely affect our business and our reputation.

Cyber-attacks or data security breaches could compromise confidential, private, business critical information or cause a failure in our computer or operating systems that may disrupt our operations. We have valuable information assets, including intellectual property, trade secrets and other sensitive, business critical information. We continue to face risk of attack from outside our organization (including cyberattacks by criminal groups, state-sponsored actors or social-activist (hacktivist) organizations) using sophisticated technical and non-technical methodologies such as social engineering and phishing attacks. Cyber threats are constantly evolving, becoming more sophisticated and being made by groups and individuals with a wide range of expertise and motives, and this increases the difficulty of detecting and successfully defending against them. We also face risks from internal threats to information security, such as from negligent or dishonest employees or consultants. A successful cyber-attack or other breach of security could result in the loss of critical business information and/or could negatively impact operations, which could have a negative impact on our financial results. Furthermore, in addition to using our own systems and infrastructure, we use information systems and infrastructure operated by third-party service providers. If our third-party service providers experience an information security breach, depending on the nature of the breach, it could compromise confidential, business critical information or cause a disruption in our operations. In addition, the loss or disclosure of sensitive or private information about our employees, vendors, or customers as a result of such a breach may result in violations of various data privacy regulations and expose us to litigation, fines and other penalties. Therefore, any such disruptions to our operations or violations of data privacy laws could negatively impact our reputation and results of operations.

Risks Related to our Information Systems

The implementation of a new enterprise resource planning system could cause disruption to our operations.

We are currently in the process of a multi-year transition to a new enterprise resource planning (“ERP”) system, which will replace most of our core financial systems, and which is expected to occur in phases over the next several years. This project was paused in 2023 as a cost control measure, and may not restart in 2024. If the implementation of the ERP system does not restart, or not proceed as expected, or does not operate as intended, could negatively impact the effectiveness of our internal control over financial reporting. Any of these types of disruptions could have a negative effect on our business, operating results, and financial condition. In addition, the eventual implementing of a new ERP system may require significant resources and refinement to fully realize the expected benefits of the system.

Risks Related to Our Ordinary Shares

Irish law differs from the laws in effect in the U.S. and may afford less protection to holders of our securities than companies formed in the U.S.

It may not be possible to enforce court judgments obtained in the U.S. against us in Ireland based on the civil liability provisions of the U.S. federal or state securities laws. In addition, there is some uncertainty as to whether the courts of Ireland would recognize or enforce judgments of U.S. courts obtained against us or our directors or officers based on the civil liabilities provisions of the U.S. federal or state securities laws or hear actions against us or those persons based on those laws. There is no treaty between Ireland and the U.S. providing for the reciprocal enforcement of foreign judgments. Therefore, a final judgment for the payment of money rendered by any U.S. federal or state court based on civil liability, whether or not based solely on U.S. federal or state securities laws, would not automatically be enforceable in Ireland.

As an Irish company, Trinseo is governed by the Irish Companies Acts, which differ in some material respects from laws generally applicable to U.S. corporations and shareholders, including, among others, differences relating to interested director and officer transactions and shareholder lawsuits. Likewise, the duties of directors and officers of an Irish company generally are owed to the company only. Shareholders of Irish companies generally do not have a personal right of action against directors or officers of the company and may exercise such rights of action on behalf of the company only in limited circumstances. Accordingly, holders of our shares may have more difficulty protecting their interests than would holders of securities of a corporation incorporated in a jurisdiction of the U.S.

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Provisions of our articles of association and Irish law could delay or prevent a takeover of us by a third party.

Our articles of association could delay, defer or prevent a third-party from acquiring us, despite the possible benefit to our shareholders. For example, our articles of association impose advance notice requirements for shareholder proposals and nominations of directors to be considered at shareholder meetings, and our articles also require supermajority approval from shareholders to amend or repeal our articles of association.

In addition, several mandatory provisions of Irish law could prevent or delay an acquisition of Trinseo. For example, Irish law does not permit shareholders of an Irish public limited company to take action by written consent with less than unanimous consent. We are also subject to provisions of Irish law relating to mandatory bids, voluntary bids, requirements to make a cash offer and minimum price requirements, as well as rules requiring the disclosure of interests in our ordinary shares in certain circumstances.

These provisions may discourage potential takeover attempts, discourage bids for our ordinary shares at a premium over the market price, and may negatively impact the voting and other rights of our shareholders. These provisions could also discourage proxy contests and make it more difficult for our shareholders to elect directors other than those nominated by our board of directors.

Any attempts to take us over will be subject to Irish Takeover Rules and subject to review by the Irish Takeover Panel.

We are subject to the Irish Takeover Rules, under which our board of directors will not be permitted to take any action which might frustrate an offer for our ordinary shares once it has received an approach which may lead to an offer or has reason to believe an offer is imminent.

As an Irish public limited company, certain capital structure decisions regarding the Company will require the approval of shareholders, which may limit the Company’s flexibility to manage its capital structure.

Irish law provides that a board of directors may allot shares (or rights to subscribe for or convertible into shares) only with the prior authorization of shareholders, for a maximum period of five years, as specified in the articles of association or relevant shareholder resolution. At our 2022 annual general meeting, shareholders authorized the allotment of up to 33% of the nominal value of the Company’s issued ordinary share capital as of March 31, 2022 for a period of 18 months. Approval from the Company’s shareholders, by ordinary resolution, being a resolution passed by a simple majority of votes cast, on or prior to expiration, will be required to renew this authorization. Our ability to issue equity without this authorization could be limited which could adversely affect our securities holders.

Irish law also generally provides shareholders with preemptive rights when new shares are issued for cash; however, it is possible for the Company’s articles of association, or shareholders in general meeting, to exclude preemptive rights. At our 2022 annual general meeting, shareholders authorized the exclusion of preemptive rights for a period of 18 months for (i) the issuance of shares for cash in connection with any rights issue; and (ii) the issuance of shares for cash not to exceed 5% of our issued ordinary share capital as of March 31, 2022 (with an additional 5% provided the company uses it for an acquisition or specified capital investment). Renewal of this exclusion requires approval by Company’s shareholders, by special resolution, being a resolution passed by not less than 75% of votes cast, on or prior to expiration. Should this exclusion not be approved, our ability to issue equity could be limited which could adversely affect our securities holders.

General Risks

Conditions in the global economy and capital markets may adversely affect our results of operations, financial condition and cash flows.

Our products are sold in markets that are sensitive to changes in general economic conditions, such as sales of automotive and construction products. Downturns in general economic conditions can cause fluctuations in demand for our products, product prices, volumes and margins.

Rising inflation and interest rates, recessions, turbulence in the credit markets, fluctuating commodity prices, volatile exchange rates, social and political instability and other challenges affecting the global economy can affect us and our customers. Instability and uncertainty in financial and commodity markets throughout the world may cause,

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among other things, severely diminished liquidity and credit availability, rating downgrades of certain investments and declining valuations and pricing volatility of others, volatile energy and raw material costs, geopolitical issues and failure and the potential failure of major financial institutions. Adverse events affecting the health of the economy, including recessionary conditions, inflation, rising interest rates, sovereign debt and economic crises, natural disasters, refugee crises, disease epidemics or pandemics, political unrest, terrorism, protectionism, tariffs, and war or the threat of war, could have a negative impact on the health of the global economy. These developments, or the perception that any of them could occur, may have a material adverse effect on global economic conditions or on the stability of global markets. For example, current macroeconomic and political instability caused by rising interest rates, inflation, geopolitical tensions, ongoing conflicts between Russia and Ukraine as well as Israel and Hamas could adversely impact global markets and our results of operations. In addition, the COVID-19 pandemic created significant worldwide social and economic volatility, leading to supply chain disruptions, increased transportation costs, and other negative consequences, and a similar disease outbreak or pandemic could negatively impact the economies in the countries in which we operate and adversely impact our business, liquidity, financial condition and results of operations. During any period of uncertainty or heightened market volatility, consumer confidence may decline which could lead to a decline in demand for our products or a shift to lower-margin products, which could adversely affect sales of our products and profitability, result in impairments of certain of our assets, and could negatively impact our business, liquidity, financial condition and results of operations.

Deterioration in the financial and credit market heightens the risk of customer bankruptcies and delay in payment. We are unable to predict the duration of the current economic conditions or their effects on financial markets, our business and results of operations. In addition, we have experienced, and expect to continue to experience, increased capital costs due to increases in global interest rates. If our access to capital were to become significantly constrained, or if costs of capital increased significantly due to increased interest rates, lowered credit ratings, prevailing industry conditions, the volatility of the capital markets or other factors, or if economic conditions were to further deteriorate, then our financial condition, our results of operations, and cash flows could be adversely affected.

As a global business, we are exposed to local business risks in different countries, which could have a material adverse effect on our financial condition or results of operations.

We have significant operations worldwide, including manufacturing facilities, R&D facilities, sales personnel and customer support operations. Our international operations are subject to risks inherent in doing business in foreign countries, including, but not necessarily limited to:

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We may not be successful in developing and implementing policies and strategies to address the foregoing factors in a timely and effective manner at each location where we do business. Consequently, the occurrence of one or more of the foregoing factors could have a material adverse effect on our international operations or upon our financial condition and results of operations.

Our operations in developing markets could expose us to political, economic and regulatory risks that are greater than those we may face in established markets. For example, we operate in some nations that have experienced significant levels of governmental corruption. Any failure by us to ensure that our employees and agents comply with applicable laws and regulations in foreign jurisdictions could result in substantial civil and criminal penalties or restrictions on our ability to conduct business in certain foreign jurisdictions or reputational damage, and our results of operations and financial condition could be materially and adversely affected.

We face competitive risks related to excess supply capacity.

Our products generally compete based on quality, reliability, customer specification, as well as our customer service and length and depth of our customer relationships.  Certain Trinseo products compete primarily on price and therefore may face greater competition where comparable products are readily available.  Excess supply capacity in the markets where we operate may create negative pricing pressure on these products.  Our competitors in certain markets, primarily in Asia, have added or may add significant production capacity, which additional supply could negatively impact our sales, pricing and margins in those regions where new capacity is added or excess supply is made available.  Our inability to compete in these markets could have a material effect on our financial condition and results of operations.

Fluctuations in currency exchange rates may significantly impact our results of operations and may significantly affect the comparability of our results between financial periods.

Our operations are conducted by subsidiaries in many countries. The results of the operations and the financial position of these subsidiaries are reported in the relevant foreign currencies and then translated into U.S. dollars at the applicable exchange rates for inclusion in our consolidated financial statements. The main currency to which we are exposed is the euro, as approximately 53% of our net sales were generated in Europe in 2023. To a lesser degree, we are also exposed to other currencies, including, among others, the Chinese yuan, South Korean won, Swiss franc, and New Taiwan dollar. The exchange rates between these currencies and the U.S. dollar have fluctuated significantly in recent years and may continue to do so in the future. A depreciation of these currencies against the U.S. dollar, in particular the euro, will decrease the U.S. dollar equivalent of the amounts derived from these operations reported in our consolidated financial statements and an appreciation of these currencies will result in a corresponding increase in such amounts. Because some of our raw material costs are procured in U.S. dollars rather than on these currencies, depreciation of these currencies may have an adverse effect on our profit margins or our reported results of operations. Conversely, to the extent that we are required to pay for goods or services in foreign currencies, the appreciation of such currencies against the U.S. dollar will tend to negatively impact our results of operations. In addition, currency fluctuations may affect the comparability of our results of operations between financial periods.

We incur currency translation risk whenever we enter into either a purchase or sale transaction using a currency other than the local currency of the transacting entity. From time to time, we enter into foreign exchange forward contracts to hedge fluctuations associated with certain monetary assets and liabilities, primarily accounts receivable, accounts payable and certain intercompany obligations. However, attempts to hedge against foreign currency fluctuation risk may not be able to effectively limit our exposure to intermediate or long-term movements in currency exchange rates, which could adversely impact our financial condition or results of operations. Given the volatility of exchange rates, there can be no assurance that we will be able to effectively manage our currency translation risks or that any volatility in currency exchange rates will not have a material adverse effect on our financial condition or results of operations.

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The following table sets forth a list of our principal offices, production sites and other facilities as of December 31, 2023:

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We believe that our properties and equipment are generally in good operating condition and are adequate for our present needs. Production capacity at our sites can vary depending upon product mix and operating conditions.

A majority of our global production facilities are certified to ISO 9001 standards. Our manufacturing facilities have established reliability and maintenance programs and leverage production between sites to maximize efficiency.

Our plants often have similar layouts, technology and manufacturing processes, depending upon the product being manufactured. We believe this global uniformity creates a key competitive advantage for us and helps lower overall operating costs.

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Stock Performance Graph

The following performance graph reflects the comparative changes in the value from December 31, 2018 through December 31, 2023, assuming an initial investment of $100 and the reinvestment of dividends or other cash distributions, if any, in (1) our ordinary shares, (2) the S&P 500 Chemicals Industry GICS Level 3 Index, and (3) the S&P SmallCap 600 Index. The share price performance shown in the graph is not necessarily indicative of future price performance.

Purchases of equity securities by the Company and affiliated purchasers

On September 2, 2022, the board of directors of the Company unanimously approved the authorization of a share repurchase program where the Company may repurchase up to $200.0 million of our ordinary shares, subject to certain parameters defined by the board of directors. The repurchase authorization expires after 18 months and repurchases may be effected through open market purchases, 10b5-1 plans or by other means. All repurchases will be carried out by way of redemption in accordance with Irish law and the Company’s constitutional documents. There were no share repurchases during the three months ended December 31, 2023. There was $200.0 million remaining for share repurchases under the 2022 share repurchase authorization as of December 31, 2023. Given the Company’s liquidity requirements and related debt covenants, it is unlikely any shares will be repurchased for the foreseeable future.

Ireland Tax Considerations

The following is a summary discussion of the material Irish tax considerations of the acquisition, ownership and disposition of your ordinary shares that may be applicable to you. It is not intended to be, nor should it be construed to be, legal or tax advice. This discussion is based on Irish laws and regulations as they stand on the date of this report and is subject to any change in law or regulations or changes in interpretation or application thereof (and which may possibly have a retroactive effect). Investors should therefore consult their own professional advisers as to the effects of state, local or foreign laws and regulations, including Irish tax law and regulations, to which they may be subject.

There are currently no governmental laws, decrees or regulations in Ireland that restrict the remittance of dividends or other payments to non-resident holders of the Company’s shares.

Dividends paid by Trinseo will generally be subject to Irish dividend withholding tax (currently at a rate of 25%). U.S. resident shareholders may claim an exemption from the dividend withholding tax by holding their shares in an account through the Depository Trust Company and having on file with their broker or qualifying agent a valid U.S.

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address on the record date of the dividend, or by completing certain Irish dividend withholding tax exemption forms or filing a certification of U.S. residency (Form 6166).

Trinseo shareholders who receive their dividends subject to Irish dividend withholding tax will generally have no further liability for Irish income tax, provided a statement is presented to the Irish authorities of the dividend withholding tax imposed.

While there are provisions in the U.S.-Ireland Double Tax Treaty regarding withholding, it would generally be unnecessary for U.S. resident shareholders to rely on the treaty provisions due to the broad scope of withholding tax exemptions available under Irish domestic law.

Item 6. Reserved

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Asset Optimization and Corporate Restructuring

In response to the challenging macroeconomic conditions noted above, during the second half of 2023, Trinseo approved asset restructuring and corporate restructuring initiatives to improve its economic position and operating flexibility, reduce its exposure to cyclical commodity markets and reduce certain general and administrative costs. These actions consisted of the following:

Sale of Matamoros, Mexico Manufacturing Facility

In April 2023, the Company entered into an agreement to sell its land, buildings and equipment at its PMMA sheet manufacturing facility in Matamoros, Mexico for a cash consideration of approximately $19.0 million, which was received in May 2023 when the transaction closed. The sale resulted in a pre-tax gain of $14.4 million recognized in the second quarter of 2023. This site was part of the previously-announced asset restructuring plan approved in the fourth quarter of 2022 to consolidate our sheet manufacturing business and optimize our resources.

Bristol Spill

On March 24, 2023, due to equipment failure at the Bristol, Pennsylvania facility, operated by our wholly-owned subsidiary, Altuglas LLC, an accidental release of a latex emulsion product occurred, which ultimately flowed into a local waterway (the “Bristol Spill”). We reported the event and cooperated closely with local, state, and federal authorities on the response activities. Water sampling conducted by the authorities did not detect site-related material in the waterway. The safety of our employees, our communities and our environment are a top priority, and we are committed to operate safely and without disturbance to our community. Refer to Note 20 in our consolidated financial statements for additional information related to this matter.

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Selling, General and Administrative Expenses

The $88.5 million, or 22%, decrease in SG&A was primarily due to a decrease of $58.9 million in costs associated with the Company’s strategic initiatives, including the exploration of a potential divestiture of our styrenics business, a $5.6 million decrease in acquisition transaction and integration costs, and a $24.2 million decrease in restructuring costs driven by the asset optimization and corporate restructuring plan approved in the third quarter of 2023 and the asset restructuring plan approved in the fourth quarter of 2022.

Equity in Earnings of Unconsolidated Affiliates

The decrease in equity earnings of $40.1 million was due mainly to lower styrene and polystyrene margins from weaker market conditions.

Impairment and other charges

During the year ended December 31, 2023, the Company recorded a non-cash goodwill impairment charge of $349.0 million related to the Engineered Materials reporting unit, as described within Note 15 in the consolidated financial statements. The Company also recorded impairment charges of $0.5 million and $6.3 million related to the Boehlen styrene monomer assets during the years ended December 31, 2023 and 2022, respectively, as described within Note 19 in the consolidated financial statements.

Interest Expense, Net

The increase in interest expense, net of $75.5 million, or 67%, was primarily attributable to the year-over-year increase in market interest rates on our variable rate debt. Refer to Note 17 in the consolidated financial statements for further information.

(Gain) Loss on Extinguishment of Long-Term Debt

Loss on extinguishment of long-term debt was $6.3 million for the year ended December 31, 2023, which related to the Company’s debt refinancing during the third quarter of 2023. This amount was primarily comprised of the write-off of unamortized deferred financing costs and unamortized original issue discount related to the 2024 Term Loan B as well as the write-off of unamortized deferred financing costs related to the 2025 Senior Notes.

A $0.8 million gain on extinguishment of debt was recorded for the year ended December 31, 2022, in relation to the repurchase of $3.0 million of the 2029 Senior Notes in the open market.

Other Expense (Income), Net

Other income, net for the year ended December 31, 2023 was $17.2 million. Other income, net was comprised of foreign exchange transaction gains of $9.1 million, which included $16.7 million of foreign exchange transaction gains primarily from the remeasurement of our euro denominated payables due to the relative changes in rates between the U.S. dollar and the euro during the period, partially offset by $7.6 million of losses from our foreign exchange forward contracts.

Other income, net for the year ended December 31, 2022 was $7.2 million. Other income, net was comprised of foreign exchange transaction gains of $8.0 million, which included $41.0 million of foreign exchange transaction losses primarily from the remeasurement of our euro denominated payables due to the relative changes in rates between the U.S. dollar and the euro during the period, more than offset by $49.0 million of gains from our foreign exchange forward contracts.

Provision for (Benefit from) Income Taxes

Provision for (benefit from) income taxes was $68.4 million and $(41.6) million for the years ended December 31, 2023 and 2022, respectively, which resulted in an effective tax rate of (11)% and 9%, respectively. The increase in provision for income taxes in 2023 was primarily due to the increase in valuation allowance adjustments of $163.7 million, predominantly in the United States and Switzerland. This was partially offset by the $163.2 million decrease in

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income from continuing operations before income taxes, as well as the revaluation of the Company’s net deferred tax assets during the second quarter of 2022, which resulted in a one-time deferred tax expense of $15.3 million.

Net Income (Loss) from Discontinued Operations, Net of Income Taxes

There was no net income from discontinued operations, net of income taxes during the year ended December 31, 2023. Net income (loss) from discontinued operations, net of income taxes during the year ended December 31, 2022 was $(2.9) million and was related to the results and sale of our Synthetic Rubber business. Refer to Note 5 in the consolidated financial statements for further information.

Selected Segment Information

The Company’s reportable segments are as follows: Engineered Materials, Latex Binders, Plastics Solutions, Polystyrene, Feedstocks, and Americas Styrenics. Refer to Item 1—Business for a description of our segments, including a detailed overview, products and end uses, and competition and customers.

The following sections present net sales, Adjusted EBITDA, and Adjusted EBITDA margin by segment for the years ended December 31, 2023, 2022, and 2021. Inter-segment sales have been eliminated. Refer to Note 24 in the consolidated financial statements for a detailed definition of Adjusted EBITDA and a reconciliation of income from continuing operations before income taxes to segment Adjusted EBITDA. Refer to the Company’s Form 10-K filed on February 27, 2023 for explanations of our segment results for 2022 in comparison to 2021.

2023 vs. 2022

The 24% decrease in net sales was primarily attributable to lower pricing, primarily from the pass through of lower raw materials and energy costs which contributed to a 14% decrease year-over-year. Lower sales volumes from weak underlying demand and continued customer destocking, primarily in building & construction, consumer electronics, and wellness applications contributed to an 11% decrease year-over-year.

Adjusted EBITDA decreased $66.7 million, or 93%, year-over-year primarily due to lower margins which decreased by $61.1 million or 85% year-over-year, as well as a decrease of $14.3 million, or 20%, due to lower sales volumes as described above. These were partially offset by lower fixed costs of $7.1 million, or 10%, primarily as the result of restructuring activities undertaken in late 2022 and 2023.

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2023 vs. 2022

The 25% decrease in net sales was primarily due to a 12% decrease in pricing from the pass through of lower raw material costs, and a 14% decrease due to lower sales volumes across most applications from customer destocking and impacts from geopolitical uncertainty.

The $17.5 million, or 16%, decrease in Adjusted EBITDA was primarily due to a decrease of $40.2 million, or 36%, from lower sales volume. These decreases were partially offset by a $25.9 million, or 23%, increase attributable to higher margins primarily due to pricing initiatives.

2023 vs. 2022

Of the 22% decrease in net sales, 10% was due to lower sales volumes, which were primarily impacted by a decrease in polycarbonate from the announced shutdown of one production line as well as in copolymers in building & construction, industrial, and consumer durables applications from customer destocking and a weaker macroeconomic environment. The volume decrease was partially offset by higher volumes to automotive applications. Also contributing to the overall decrease was a 12% decrease from lower pricing due to the pass through of lower raw material costs.

The $2.0 million, or 2%, decrease in Adjusted EBITDA was primarily due to lower sales volume of $8.6 million, or 9%. These decreases were partially offset by lower fixed costs which contributed a $2.8 million, or 3%, increase in Adjusted EBITDA. Margins also improved 2% versus prior year leading to a $1.5 million increase in Adjusted EBITDA.

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2023 vs. 2022

Net sales decreased by 32% year-over-year. Lower sales volumes, primarily due to customer destocking and a weak overall demand environment amid falling raw material prices, led to a 16% decrease in net sales from prior year. Also contributing to the overall decrease was a 17% decrease from lower pricing, primarily from the pass through of lower styrene costs.

The $66.0 million, or 66%, decrease in Adjusted EBITDA was due to a decrease of $33.3 million, or 34%, from lower margins and a decrease of $27.5 million, or 28%, due to lower volumes. Weaker demand, including in building & construction and appliance applications, contracted margins and led to lower volumes. Also contributing to the overall decrease was a $5.3 million, or 5%, decrease from higher fixed costs.