Trinseo PLC TSEOQ US Equity☆

Item 1A. Risk Factors

Risks Related to Our Operations

We are subject to risks associated with the Company’s strategy to transform its portfolio to a specialty materials and sustainable solutions provider.

We have taken steps toward executing on our publicly-disclosed strategy to transform the Company to a specialty materials and sustainable solutions provider, including the PMMA Acquisition and Aristech Surfaces Acquisition, the sale of our synthetic rubber business, and the plan to explore the divestiture of our styrenics businesses. We plan to continue to prioritize investments in higher growth, higher margin and lower earnings volatility areas such as Engineered Materials and CASE applications, and to deemphasize the more volatile, lower growth assets in our portfolio. We cannot guarantee that the execution of this strategy will lead to higher growth or margins and lower earnings volatility. We also cannot be certain that we will be successful in identifying opportunities for 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.

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. 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, 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.

Volatility in the cost of raw materials, logistics services, energy, or transportation utilized for our products, or disruption in the supply of the raw materials utilized for our products, 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 (benzene, ethylene, butadiene, BPA, MMA, and styrene) together represent approximately 81% of our total cost of goods sold. Additionally, we use natural gas and electricity to operate our facilities and generate heat and steam for our various manufacturing processes. 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 are dependent on third-party freight carriers to transport many of our products. Our access to third-party freight carriers is not guaranteed, and we may be unable to transport our products at economically attractive rates in certain circumstances, particularly during disruptions to transportation infrastructure. Our business, financial position, results of operations or cash flows could be materially and adversely affected if we are unable to pass all of the cost increases on to our customers, or if freight carrier capacity in our geographic markets were to decline significantly or otherwise become unavailable.

We have supply agreements with Dow for ethylene, benzene, butadiene, and MMA, which are critical raw materials to our business. These raw materials and other less critical materials amount to approximately 22% of our total raw materials acquired in 2021, 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

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renew these contracts, or obtain new long-term supply agreements on terms comparable or favorable 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 or on favorable terms.

Production at our manufacturing facilities could be disrupted for a variety of reasons. Disruptions could expose us to significant losses or liabilities.

The hazards and risks of disruption associated with chemical manufacturing and the related storage and transportation of raw materials, products and wastes 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:

● pipeline and storage tank leaks and ruptures;

● explosions and fires;

● terrorist attacks;

● cyber-attacks;

● failures or delays in properly implementing new technologies and processes;

● exposure to toxic chemicals.

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. Furthermore, the environmental, health and safety compliance, management systems, and emergency response and crisis management plans we have in place may not address or foresee all potential risks or causes of disruption.

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. Delays or cost increases related to capital and other spending programs involving engineering,

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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:

● disruptions in transportation of components or construction materials;

● disease outbreaks, epidemics or pandemics, and government responses thereto;

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.

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 our proposed divestiture of our styrenics businesses.

In November 2021 we announced our intention to explore the divestiture of our styrenics businesses, for which we launched a formal sales process in January 2022. We cannot guarantee that we will be successful in our efforts to initiate and generate interest in a sale or auction process, locate an adequate buyer, or negotiate terms of a sale agreement acceptable to the Company. Identifying and completing any potential sale transaction would depend on a number of factors, many of which are beyond our control, including, among other things, market conditions, third-party consents, regulatory approvals, and the availability of financing for potential buyers, if required. 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 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.

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We may fail to realize the anticipated benefits of the PMMA Acquisition and the Aristech Surfaces Acquisition or such benefits may take longer to realize than expected. We may also encounter difficulty integrating these businesses into our operations, or challenges related to our reliance on transition services.

On May 3, 2021, we completed the PMMA Acquisition for a purchase price of $1,364.9 million, and on September 1, 2021, we completed the Aristech Surfaces Acquisition for a purchase price of $449.5 million (together, the “Acquisitions”).

Our ability to realize the anticipated benefits of the Acquisitions will depend on our ability to successfully integrate the PMMA business and the Aristech Surfaces business into ours. Combining these businesses continues to be a complex and time-consuming process and the Company has devoted significant attention and resources integrating the operations, systems, processes, procedures and personnel of the acquired businesses, and we expect to continue to do so. If we fail to effectively integrate, or if integration takes longer or is more costly than expected, we could lose or diminish the expected benefits of the Acquisitions. Even if we are able to integrate successfully, this integration may not result in the realization of the cost and revenue synergies and benefits that we currently expect, 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 and manage growth profitability, achieve expected margins, maintain relationships with customers or retain key employees. We may also be adversely affected by other economic, business, and/or competitive factors which may not have existed at the time of closing. Such conditions could materially adversely impact our business and results of operations.

Additionally, we rely on Arkema to provide certain services, including information technology, accounting and financial reporting services, pursuant to transition services agreements executed in connection with the PMMA Acquisition. While such services are scheduled to be taken over by Trinseo in 2022, Arkema’s failure to perform could negatively impact our ability to close our books in an accurate and timely manner as well as our ability to complete our financial statements or financial reporting.

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

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

● difficulty maintaining relationships with customers;

● hiring additional management and other critical personnel;

● generating expected cost savings and synergies from the acquisition; and

● increasing the scope, geographic diversity and complexity of our operations.

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.

In November 2021, we announced the Company’s intent to explore the potential divestiture of our styrenics businesses, for which we launched a formal sales process in January 2022, and in December 2021, we successfully completed the divestiture of our Synthetic Rubber business. 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”) and the indentures governing our $500.0 million aggregate principal of 5.375% senior notes due 2025 (the “2025 Senior Notes”), and our $450.0 million aggregate principal of 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, 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.

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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, 2021, we received dividends of $85.0 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.

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

Beginning in 2019 and continuing through 2021, we announced certain restructuring programs associated with our shift to a global functional structure, the adoption of our business excellence initiatives designed to create ongoing cost savings through business process optimization and efficiencies, and related more broadly to our overall transformation strategy. 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.

Risks Related to Regulation

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.

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, over the past several years the U.S. and China have applied tariffs to certain of each other’s exports. These measures 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.

The adoption and expansion of 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.

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Regulatory and statutory changes applicable to our raw materials and products and our customers’ products and consumer preferences 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, health, sustainability, and safety concerns could increase the costs incurred by our customers to use our products and otherwise limit the use of these products, which could lead to decreased demand for these products. Such a decrease in demand likely would have an adverse effect on our business and results of operations. Materials such as acrylonitrile, ethylbenzene, styrene, butadiene, BPA, MMA, and halogenated flame retardant are used in the manufacturing of our products and have come under scrutiny due to potentially significant or perceived health and safety concerns. Moreover, bans on single-use plastic and similar regulatory actions to reduce plastic waste and consumer preferences for sustainable and recyclable materials may reduce the demand for some of our products over time. Legislation to place responsibility for addressing the global challenge of plastic waste may place responsibility on producers and sellers to include recycled content in their products, including the EU “plastics tax,” which 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.

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.

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Trinseo Europe GmbH, one of our subsidiaries, received a Request for Information from the European Commission Directorate General for Competition, involving commercial activity for styrene monomer. To the extent the European Commission’s inquiry would lead to a finding that the Company’s subsidiary violated the law, the results of this finding could have a material adverse effect on our business, financial condition, results of operations, and cash flows.

On June 6, 2018, Trinseo Europe GmbH, a subsidiary of the Company, received a Request for Information in the form of a letter from the European Commission Directorate General for Competition (the “European Commission”) related to styrene monomer commercial activity in the European Economic Area. In addition, the Company commenced an internal investigation into the matter and has discovered instances of inappropriate activity. On October 28, 2019, a supplemental request for information was received from the European Commission. This request was limited to historical employment, entity, and organizational structures, along with certain financial, styrene purchasing, and styrene market information, as well as certain spot styrene purchase contracts. We have provided this information to the European Commission and continue to fully cooperate with the Request for Information.

The proceedings with the European Commission continue and its outcome remains open. Based on its findings, the European Commission may decide to: (i) require further information; (ii) conduct unannounced raids of the Company’s premises; (iii) adopt decisions imposing fines and/or certain behavioral or structural commitments from the Company; or (iv) in view of defense arguments by the Company close the proceedings. If Trinseo Europe GmbH is found to have violated one or more laws, it could also be subject to additional actions by local competition authorities. European Commission inquiries or investigations can continue over a long period of time, which can divert the attention of our management from day-to-day operations and impose significant administrative burdens. Any of these consequences could damage our reputation and impair our ability to conduct business, which could have a material adverse effect on our business, financial condition, results of operations, and cash flows.

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 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. 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 now own on which Dow has been conducting remediation to address historical contamination. Those properties include Allyn’s Point, Connecticut and Dalton, Georgia. There are other properties with historical contamination that are owned by Dow that we lease for our operations, including our facility in Midland, Michigan. 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. Later-acquired sites are subject to a different limitations period. 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. Other than certain immaterial

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environmental liabilities assumed as part of the PMMA Acquisition and the Aristech Surfaces Acquisition, no environmental claims have been asserted or threatened against the Company, and the Company is not a potentially responsible party for any material amounts at any Superfund Sites.

Risks Related to Our Indebtedness

Our current and future level of indebtedness of our subsidiaries, including the incurrence of additional indebtedness to fund the PMMA Acquisition, could adversely affect our financial condition.

As of December 31, 2021, our indebtedness totaled approximately $2.3 billion. Additionally, as of December 31, 2021, we had $368.6 million (net of $6.4 million outstanding letters of credit) of funds available for borrowing under our Senior Credit Facility, as well as $150.0 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:

● increasing our cost of borrowing.

Although the terms of our senior secured credit agreement (the “Credit Agreement”) governing our Senior Credit Facility, and the indentures governing the 2029 Senior Notes and 2025 Senior Notes (the “Indentures”), 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 Senior Credit Facility or the Indentures, 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, please 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.

The Indentures and the Credit Agreement 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:

● sell or assign assets;

● incur additional indebtedness;

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● pay dividends to Trinseo PLC;

● make investments or acquisitions;

● incur liens;

● repurchase or redeem capital shares;

● engage in mergers or consolidations;

● materially alter the business they conduct;

● engage in transactions with affiliates; and

● consolidate, merge or transfer all or substantially all of their assets.

The ability of our subsidiaries to comply with the covenants and financial ratios and tests contained in the Indentures and the Credit Agreement, 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, 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 or Indentures or our inability to comply with the required financial ratios 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.

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:

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, on terms as favorable to us or at all. For more information regarding our relationship with Dow, please see Item 1—Business — Our Relationship with Dow.

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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 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.

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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.

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 attractive information assets, including intellectual property, trade secrets and other sensitive, business critical information. We face an ever-growing risk of attack from outside our organization (including attacks by organized crime, so-called “hacktivists,” and state-sponsored actors) using sophisticated technical and non-technical methodologies (including social engineering and “spear phishing” attacks). 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 currently scheduled to be fully implemented in 2023. If the implementation of the ERP system does not proceed as expected, it could impede our ability to accurately maintain financial records and share financial data across the company. Failure to successfully implement the ERP system as planned, or if the ERP system 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, implementing a new ERP system may require significant resources and refinement to fully realize the expected benefits of the system.

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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 U.S. companies.

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.

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, such authorization for a maximum period of five years, each as specified in the articles of association or relevant shareholder resolution. This authorization would need to be renewed by the Company’s shareholders upon its expiration (i.e., at least every five years). Initially, the Company’s articles of

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association authorized the allotment of shares for a period of five years from the date of their adoption, which authorization expires in May 2026. Any such authorization must be renewed by ordinary resolution, being a resolution passed by a simple majority of votes cast, prior to expiration. 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. Such an exclusion of preemptive rights may be for a maximum period of up to five years from the date of adoption of the articles of association, if the exclusion is contained in the articles of association, or from the date of the shareholder resolution, if the exclusion is by shareholder resolution; in either case, this exclusion would need to be renewed by Company’s shareholders upon its expiration (i.e., at least every five years). Initially the Company’s articles of association exclude preemptive rights for a period of five years from the date of adoption of the Company’s articles of association, which exclusion expires in May 2026. Any such exclusion must be renewed by special resolution, being a resolution passed by not less than 75% of votes cast, upon 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.

Turbulence in the credit markets, fluctuating commodity prices, volatile exchange rates 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, 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 sovereign debt and economic crises, refugee crises, disease pandemics, terrorism, protectionism, tariffs, and 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 financial markets. 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 our profitability and could also result in impairments of certain of our assets.

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. If economic conditions deteriorate, our results of operations, financial condition and cash flows could be materially 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. As of December 31, 2021, we operated, or others operated on our behalf, 40 manufacturing plants (which include a total of 81 production units) at 33 sites around the world, including in Colombia, Germany, The Netherlands, Belgium, Finland, Sweden, Italy, France, Denmark, China, South Korea, Indonesia, Taiwan, Mexico, and the United States. Our international operations are subject to risks inherent in doing business in foreign countries, including, but not necessarily limited to:

● new and different legal and regulatory requirements in local jurisdictions;

● restrictive labor and employment laws;

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● tariffs, export duties, or import quotas;

● domestic and foreign customs and tariffs or other trade barriers;

● potential staffing difficulties and labor disputes;

● managing and obtaining support and distribution for local operations;

● increased costs of transportation or shipping;

● credit risk and financial conditions of local customers and distributors;

● potential difficulties in protecting intellectual property;

● risk of nationalization of private enterprises by foreign governments;

● potential imposition of restrictions on investments;

● foreign currency exchange restrictions and fluctuations; and

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.

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 57% of our net sales were generated in Europe in 2021. To a lesser degree, we are also exposed to other currencies, including, among others, the Chinese yuan, Swiss franc, New Taiwan dollar, and Mexican peso. 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 be unsuccessful, and we 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

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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.

The extent to which the COVID-19 pandemic will continue to impact our business, financial condition and results of operations could be material.

The COVID-19 pandemic has created significant worldwide social and economic volatility, uncertainty and disruption. The pandemic has resulted in curtailment of business activities, suspensions or delays of production and commercial activity, government-mandated travel restrictions, and weakened economic conditions in the countries in which we operate.

The extent to which the COVID-19 pandemic will continue to adversely impact our business, liquidity, financial condition and results of operations, which impact could be material, depends on numerous factors. These factors include the duration and scope of the pandemic, including an increase in infections, new variants of the virus, and renewed travel restrictions and “shelter-in-place” directives.

Other factors resulting from the pandemic which may negatively impact our business and results of operations include increased costs or disruption in the availability of raw materials and feedstocks; increased energy prices; increased freight or transportation costs; global price inflation; our relationship with, and the financial and operational capacities of, our customers and suppliers; the health and safety of our employees while maintaining continued operations; potential future restructuring, impairment and other charges; and the impact on economic activity generally, including a global or national recession, or other sustained adverse market conditions.

The COVID-19 pandemic has also significantly disrupted supply chains, transportation and logistics networks, and may further affect the ability of our third-party suppliers’ or logistics and transportation service providers to meet their obligations to us, which may negatively affect our operations. Ports and other channels of entry may be closed or operate at only a portion of capacity, and means of transporting products within regions or countries in which we operate may be limited. Plant closures, production delays, or logistics difficulties resulting from the COVID-19 pandemic may cause shortages or limited availability of feedstocks or raw materials that are used in our products, which may adversely impact our business, production capacity or results of operations.

Our efforts to manage and mitigate these factors and risks may not be successful and are subject to the factors described above, many of which are uncertain or outside of our control. Business disruptions relating to the pandemic, including the impact of new variants or an increased spread of infections could negatively impact our outlook, share price, or the economies in the countries in which we operate, which would adversely impact our business and results of operations.

Item 1B. Unresolved Staff Comments

None.

Item 2. Properties

We own and operate 67 production units at 26 sites around the world. In addition, we source products from another 14 production units at 7 joint venture sites. We also own or lease other properties, including office buildings, warehouses, research and development facilities, testing facilities and sales offices.

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The following table sets forth a list of our principal offices, production sites and other facilities as of December 31, 2021:

​ ​ ​ ​ ​

​ ​ ​ ​ ​

Site Name Location Leased/owned Products/Functions Business Segments

Corporate Offices ​ ​ ​ ​ ​

Dublin ​ Ireland ​ Leased ​ Corporate office ​ Not applicable ​

Berwyn ​ USA (PA) ​ Leased ​ Global operating center ​ Not applicable ​

Hong Kong ​ Hong Kong ​ Leased ​ Regional operating center ​ Not applicable ​

Horgen ​ Switzerland ​ Leased ​ Regional operating center ​ Not applicable ​

Midland ​ USA (MI) ​ Leased ​ Regional operating center ​ Not applicable ​

​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Production Sites ​ ​ ​ ​ ​ ​ ​ ​ ​

Belen ​ USA (NM) ​ Owned ​ PMMA Sheets ​ Engineered Materials ​

Boehlen* ​ Germany ​ Leased ​ Styrene monomer ​ Feedstocks ​

Bristol ​ USA (PA) ​ Leased ​ PMMA Resins ​ Engineered Materials ​

Bronderslev ​ Denmark ​ Leased ​ PMMA Sheets ​ Engineered Materials ​

Dalton ​ USA (GA) ​ Owned ​ Latex ​ Latex Binders ​

Florence ​ USA (KY) ​ Owned ​ PMMA Sheets ​ Engineered Materials ​

Hamina ​ Finland ​ Owned ​ Latex ​ Latex Binders ​

Hoek ​ The Netherlands ​ Owned ​ Compounds and blends ​ Base Plastics ​

Matamoros ​ Mexico ​ Owned ​ PMMA Sheets ​ Engineered Materials ​

Merak++ ​ Indonesia ​ Owned ​ Latex, Polystyrene ​ Latex Binders, Polystyrene ​

Midland* ​ USA (MI) ​ Leased ​ Latex, ABS, SAN ​ Latex Binders, Base Plastics ​

Mussolente ​ Italy ​ Owned ​ TPEs ​ Engineered Materials ​

Norrkoping ​ Sweden ​ Owned ​ Latex ​ Latex Binders ​

Porto Marghera ​ Italy ​ Owned ​ MMA ​ Engineered Materials ​

Rheinmünster* ​ Germany ​ Owned ​ Latex ​ Latex Binders ​

Rho ​ Italy ​ Owned ​ PMMA Resins, PMMA Sheets, MMA ​ Engineered Materials ​

Saint Avold ​ France ​ Owned ​ PMMA Sheets ​ Engineered Materials ​

Schkopau* ​ Germany ​ Leased ​ Polystyrene ​ Polystyrene ​

Stade* ​ Germany ​ Leased ​ PC ​ Base Plastics ​

Tessenderlo* ​ Belgium ​ Leased ​ Polystyrene ​ Polystyrene ​

Tsing Yi+ ​ Hong Kong ​ Leased ​ Polystyrene ​ Polystyrene ​

Ulsan ​ Korea ​ Owned ​ Latex ​ Latex Binders ​

Zhangjiagang* ​ China ​ Leased ​ Latex, ABS ​ Latex Binders, Base Plastics ​

​ ​ ​ ​ ​ ​ ​ ​ ​ ​

R&D Facilities ​ ​ ​ ​ ​ ​ ​ ​ ​

Dalton ​ USA (GA) ​ Owned ​ Latex ​ Latex Binders ​

Florence ​ USA (KY) ​ Leased ​ PMMA Sheets ​ Engineered Materials ​

Hsinchu ​ Taiwan ​ Owned ​ Compounds and blends, TPEs ​ Engineered Materials ​

Midland 1300 ​ USA (MI) ​ Leased ​ Latex ​ Latex Binders ​

Mussolente ​ Italy ​ Owned ​ TPEs ​ Engineered Materials ​

Rheinmünster ​ Germany ​ Owned ​ Latex ​ Latex Binders ​

Rho ​ Italy ​ Owned ​ PMMA Resins ​ Engineered Materials ​

Shanghai ​ China ​ Leased ​ Latex ​ Latex Binders ​

​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Joint Venture ​ ​ ​ ​ ​ ​ ​ ​ ​

Americas Styrenics ​ ​ ​ ​ ​ ​ ​ ​ ​

Allyn’s Point ​ USA (CT) ​ Leased ​ Polystyrene ​ Americas Styrenics ​

Cartegena ​ Colombia ​ Owned ​ Polystyrene ​ Americas Styrenics ​

Hanging Rock ​ USA (OH) ​ Leased ​ Polystyrene ​ Americas Styrenics ​

Joliet ​ USA (IL) ​ Owned ​ Polystyrene ​ Americas Styrenics ​

Marietta ​ USA (OH) ​ Owned ​ Polystyrene ​ Americas Styrenics ​

St. James ​ USA (LA) ​ Owned ​ Styrene monomer ​ Americas Styrenics ​

Torrance ​ USA (CA) ​ Leased ​ Polystyrene ​ Americas Styrenics ​

+ Facility located on property owned by the applicable government.

++ Facility located on property under certification with right to build.

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.

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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 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.

Item 3. Legal Proceedings

From time to time we may be subject to various legal claims and proceedings incidental to the normal conduct of business, relating to such matters as product liability, antitrust, competition, waste disposal practices, release of chemicals into the environment, current and former employees, and other matters that may arise in the ordinary course of our business. We currently believe that there is no litigation pending that is likely to have a material adverse effect on our business. Regardless of the outcome, legal proceedings can have an adverse impact on us because of defense and settlement costs, diversion of management resources and other factors.

Item 4. Mine Safety Disclosures

Not applicable.

PART II

Item 5. Market for Registrant’s Common Equity, Related Shareholder Matters, and Issuer Purchases of Equity Securities

The principal market on which our ordinary shares is traded is the New York Stock Exchange (“NYSE”), under the ticker symbol “TSE.” As of February 10, 2022, there were two record holders of our ordinary shares, 38,909,210 ordinary shares issued, and 37,083,547 ordinary shares outstanding. We have approximately 24,779 beneficial holders who hold shares through brokerage accounts under street names.

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Performance Graph

The following performance graph reflects the comparative changes in the value from December 31, 2016 through December 31, 2021, 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.

​

​

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Purchases of equity securities by the Company and affiliated purchasers

On December 2, 2021, 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 1.0 million share repurchases during the three months ended December 31, 2021, for total payments of $48.1 million (with $1.9 million of additional repurchases that were not yet settled but which were accrued on the consolidated balance sheet as of December 31, 2021). As a result, there was $151.9 million remaining for share repurchases under the 2021 share repurchase authorization as of December 31, 2021.

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. 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

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

The following discussion summarizes the significant factors affecting the operating results, financial condition, liquidity and cash flows of our Company as of and for the periods presented below. The following discussion and analysis should be read in conjunction with the audited consolidated financial statements and the accompanying notes thereto, included elsewhere within this Annual Report. The statements in this discussion regarding industry outlook, our expectations regarding our future performance, liquidity and capital resources and all other non-historical statements in this discussion are forward-looking statements and are based on the beliefs of our management, as well as assumptions made by, and information currently available to, our management and are made as of the date of this Annual Report. See “Cautionary Note Regarding Forward-Looking Statements.” Actual results could differ materially from those discussed in or implied by forward-looking statements as a result of various factors, including those discussed below and elsewhere within this Annual Report, particularly in Item 1A—“Risk Factors.” Definitions of capitalized terms not defined herein appear in the notes to our consolidated financial statements.

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2021 Highlights

For the year ended December 31, 2021, we had net income from continuing operations of $279.6 million and Adjusted EBITDA of $729.4 million. The Company’s legacy businesses performed very well throughout 2021, and were further supplemented by our acquisitions in the Engineered Materials segment. These very strong results were achieved, despite challenging industry operating conditions that arose during the second half of the year, including high utility costs and constraints in material, labor and energy. Additionally, the Company delivered strong cash generation during 2021 and returned significant cash to our shareholders, purchasing approximately 1.0 million ordinary shares for total value of $50.0 million and declaring quarterly dividends for an aggregate value of $0.80 per ordinary share, or $31.4 million. Refer to the discussion below for further information and refer to “Non-GAAP Performance Measures” for discussion of our use of non-GAAP measures in evaluating our performance and a reconciliation of these measures. Highlights for the year are described below.

Portfolio Transformation: In 2021, we made significant strides in the Company’s strategy to transform into a higher growth, higher margin and less cyclical specialty and sustainable materials provider. Key achievements in this transformation during the year include the following (refer to Note 4 and 5 in the consolidated financial statements for further information):

The assets and liabilities of our Synthetic Rubber business are classified as held-for-sale in our prior period balance sheet and the associated operating results of the Synthetic Rubber business are classified as discontinued operations for all periods presented.

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​

Capital Structure and Shareholder Return: In 2021, we executed transactions and took steps to improve and streamline the Company’s infrastructure, adjust our capital structure to support strategic initiatives, and return value to our shareholders. The key specific actions we took during the year in this pursuit include:

​

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Results of Operations

Results of Operations for the Years Ended December 31, 2021, 2020, and 2019

The table below sets forth our historical results of operations, and these results as a percentage of net sales for the periods indicated. Prior period amounts herein have been recast in conjunction with adjustments made for the Company’s classification of the Synthetic Rubber business as discontinued operations.

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ ​ Year Ended ​

​ ​ ​ December 31, ​

Impairment charges ​ ​ ​ 6.8 ​ — % ​ ​ 11.0 ​ — % ​ ​ — ​ — %

Interest expense, net ​ ​ 79.4 ​ 2 % ​ 43.6 ​ 2 % ​ 39.3 ​ 1 %

Other expense, net ​ ​ 9.5 ​ — % ​ 7.9 ​ — % ​ 3.4 ​ — %

Provision for income taxes ​ ​ 70.9 ​ 1 % ​ 42.7 ​ 2 % ​ 12.7 ​ — %

Net income ​ ​ $ 440.0 ​ 9 % ​ $ 7.9 ​ — % ​ $ 92.0 ​ 4 %

2021 vs. 2020

Net Sales

Of the 76% increase in net sales, 53% was due to higher selling prices resulting mainly from the pass through of higher raw material costs. An additional 17% increase was due to the contribution from our acquisitions in 2021, including the PMMA Acquisition, which closed on May 3, 2021 and the Aristech Surfaces Acquisition, which closed on September 1, 2021. Higher sales volume increased net sales by 4%.

Cost of Sales

The 70% increase in cost of sales was primarily attributable to a 48% increase in raw material costs, an 18% increase related to our acquisitions, and a 5% increase from higher utility costs.

Gross Profit

The increase in gross profit of 118% was primarily attributable to higher margins from strong demand and tight supply mainly in polystyrene, ABS, and PC, higher volume in Latex Binders, Base Plastics and Engineered Materials, as well as contributions from our acquisitions. See the segment discussion below for further information.

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Selling, General and Administrative Expenses

The $95.9 million, or 42%, increase in SG&A was primarily due to an increase in personnel costs of $42.5 million due to the Company’s improved performance during 2021 and the addition of personnel from acquisitions, as well as an increase of $44.4 million in acquisition transaction and integration costs, primarily related to the PMMA Acquisition and the Aristech Surfaces Acquisition. There were additional increases of $13.8 million from costs associated with the Company’s strategic initiatives and $6.4 million attributable to foreign exchange rate impacts. These increases were partially offset by a decrease of $18.1 million from lower advisory and professional fees, mainly related to the Company’s transition of business and technical services from Dow in 2020.

Equity in Earnings of Unconsolidated Affiliates

The increase in equity earnings of $25.7 million was due to higher equity earnings from Americas Styrenics, mainly attributable to higher polystyrene sales volume and higher polystyrene and styrene margins in North America.

Impairment Charges

During the years ended December 31, 2021 and 2020, the Company recorded impairment charges of $6.8 million and $11.0 million, respectively, primarily related to our Boehlen styrene monomer assets. Refer to Note 14 in the consolidated financial statements for further information.

Interest Expense, Net

The increase in interest expense, net of $35.8 million, or 82%, was primarily attributable to the Company’s issuance of the 2029 Senior Notes in the first quarter of 2021 and the 2028 Term Loan B during the second quarter of 2021. Refer to Note 12 in the consolidated financial statements for further information.

Acquisition purchase price hedge loss (gain)

During the years ended December 31, 2021 and 2020, the Company recorded an acquisition purchase price hedge loss (gain) of $22.0 million and $(7.3) million, respectively, due to the change in fair value of the Company’s forward currency hedge arrangement on the euro-denominated purchase price of the PMMA business.

Other Expense, Net

Other expense, net for the year ended December 31, 2021 was $9.5 million, which included $5.2 million of expense related to the non-service cost components of net periodic benefit cost and $4.5 million of transfer taxes associated with the PMMA Acquisition. These expense amounts were partially offset by foreign exchange transaction gains of $1.3 million, which included $61.9 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 $63.2 million of gains from our foreign exchange forward contracts, excluding the acquisition purchase price hedge. Also included in Other expense, net was $0.5 million of loss on extinguishment of debt related to the Company's new financing arrangements entered into during the year.

Other expense, net for the year ended December 31, 2020 was $7.9 million, which included $5.5 million of expense related to the non-service cost components of net periodic benefit cost and foreign exchange transaction losses of $1.9 million. Net foreign transaction losses included $24.4 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, which were more than offset by $26.3 million of losses from our foreign exchange forward contracts, excluding the acquisition purchase price hedge.

Provision for Income Taxes

Provision for income taxes was $70.9 million and $42.7 million for the years ended December 31, 2021 and 2020, which resulted in an effective tax rate of 20% and 40%, respectively. The increase in provision for income taxes was primarily driven by the $245.1 million increase in income from continuing operations before income taxes, partially offset by a release of a valuation allowance of $16.3 million in 2021, as a result of improvements in business operations and projected future results of the Company’s subsidiaries in China.

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

Net income (loss) from discontinued operations, net of income taxes during the years ended December 31, 2021 and 2020 was $160.4 million and $(54.8) million, respectively, and was related to the results of our Synthetic Rubber business, including the divestiture of the business on December 1, 2021. This sale resulted in the recognition of an after-tax gain of $117.8 million, which is reflected in the results for the year ended December 31, 2021. Refer to Note 5 in the consolidated financial statements for further information.

2020 vs. 2019

Net Sales

Of the 19% decrease in net sales, 13% was due to lower selling prices resulting mainly from the pass through of lower raw material costs. An additional 6% decrease was due to lower sales volume, primarily within the Base Plastics and Feedstocks segments, mainly due to the impacts related to the COVID-19 pandemic.

Cost of Sales

Of the 21% decrease in cost of sales, 16% was due to lower raw material costs, primarily from styrene and butadiene, as well as a 5% decrease due to lower sales volume primarily from the Base Plastics and Feedstocks segments.

Gross Profit

The decrease in gross profit of 7% was primarily to lower sales volumes related to COVID-19 as well as an unfavorable net raw material timing impact in comparison to the prior year. See the segment discussion below for further information.

Selling, General and Administrative Expenses

The $49.4 million, or 18%, decrease in selling, general, and administrative expenses was due to several factors. Lower advisory and professional fees, mainly related to the Company’s transition of business and technical services from Dow, which was largely completed in the first quarter of 2020, resulted in a $28.2 million decrease. Also contributing to the decrease were various management actions taken to control operating costs in response to COVID-19, including a $9.7 million decrease in travel-related expenses, as well as a decrease in restructuring costs of $12.5 million, primarily related to the Company's corporate restructuring program, which was initiated in the fourth quarter of 2019. Partially offsetting these decreases was an increase in acquisition costs of $7.5 million, which was principally attributable to the costs incurred in 2020 related to the proposed acquisition of the Arkema business.

Equity in Earnings of Unconsolidated Affiliates

The decrease in equity earnings of $52.0 million was due to lower equity earnings from Americas Styrenics, mainly attributable to lower styrene margins and volume-related impacts from COVID-19 in 2020.

Impairment Charges

During the year ended December 31, 2020, the Company recorded impairment charges of $11.0 million related to our Boehlen styrene monomer assets. There were no impairment charges recorded during the year ended December 31, 2019. Refer to Note 14 in the consolidated financial statements for further information.

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Interest Expense, Net

The $4.3 million, or 11%, increase in interest expense, net was primarily attributable to a $7.4 million reduction in interest benefit recorded as a result of the Company’s entry into a new CCS arrangement in February 2020. This was partially offset by the net decrease in interest expense of $2.6 million attributable to lower interest rates during 2020 as compared to 2019.

Acquisition purchase price hedge loss (gain)

During the year ended December 31, 2020, the Company recorded an acquisition purchase price hedge gain of $7.3 million due to the change in fair value of the Company’s forward currency hedge arrangement on the euro-denominated purchase price of the PMMA business. No such gains or losses were recognized in 2019.

Other Expense, Net

Other expense, net for the year ended December 31, 2020 was $7.9 million, which included $5.5 million of expense related to the non-service cost components of net periodic benefit cost and foreign exchange transaction losses of $1.9 million. Net foreign transaction losses included $24.4 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, which were more than offset by $26.3 million of losses from our foreign exchange forward contracts, excluding the acquisition purchase price hedge.

Other expense, net for the year ended December 31, 2019 was $3.4 million, which included $5.3 million of expense related to the non-service cost components of net periodic benefit cost and foreign exchange transaction gains of $1.6 million. Net foreign transaction losses included $6.4 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, which were more than offset by $8.0 million of gains from our foreign exchange forward contracts.

Provision for Income Taxes

Provision for income taxes was $42.7 million and $12.7 million for the years ended December 31, 2020 and 2019, which resulted in an effective tax rate of 40% and 13%, respectively. The increase in the provision for income taxes was primarily driven by the one-time deferred tax benefit of $65.0 million recorded in 2019 as a result of changes in the Swiss federal and cantonal tax rules. This one-time benefit was partially offset by a $25.3 million valuation allowance for the portion of the cantonal deferred tax asset that more likely than not will expire before utilization. Refer to Note 15 in the consolidated financial statements for further information. Excluding this one-time net benefit of $39.7 million in 2019, the provision for income taxes decreased $9.7 million, due primarily to the decrease in income from continuing operations before income taxes.

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

Net income (loss) from discontinued operations, net of income taxes during the years ended December 31, 2020 and 2019 was $(54.8) million and $4.9 million, respectively, and was related to the results of our Synthetic Rubber business. The results for the year ended December 31, 2020 were adversely impacted by significant headwinds to the Synthetic Rubber business from COVID-19 impacts, as well as impairment charges of $28.1 million recorded during the period. 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, Base Plastics, 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, 2021, 2020, and 2019. Inter-segment sales have been eliminated. Refer to Note 20 in the consolidated financial statements for a detailed definition of Adjusted EBITDA and a reconciliation of income from

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continuing operations before income taxes to segment Adjusted EBITDA. Beginning in the second quarter of 2021, the Company reported the results of the Synthetic Rubber business, as discontinued operations in the consolidated statement of operations for all periods presented, and therefore, it is no longer presented as a separate reportable segment. Refer to Note 5 in the consolidated financial statements for further information.

Engineered Materials Segment

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended ​ ​ ​ ​ ​

​ ​ December 31, ​ ​ Percentage Change ​ ​

Adjusted EBITDA margin ​ 13 % ​ 18 % ​ 15 % ​ ​ ​ ​ ​ ​

2021 vs. 2020

Of the $560.1 million, or 287%, increase in net sales, $468.4 million, or 240%, was attributable to the contribution from the acquisitions of the PMMA business and Aristech Surfaces. An additional 26% was attributable to increased sales volumes, mostly due to higher sales to consumer electronics customers in Asia, and an additional 19% was due to increased prices primarily from the pass through of higher raw materials.

Adjusted EBITDA increased $60.2 million, or 174%, of which $71.0 million, or 206%, was attributable to the contribution from the acquisitions of the PMMA business and Aristech Surfaces. Also contributing to the change was an increase of 61% from increased sales volumes, mainly to consumer electronics customers in Asia, offset by a decrease of 78% from lower margins due to higher raw materials costs and a decrease of 12% due to higher fixed costs. During the fourth quarter of 2021, including the acquired businesses, segment results were lower than anticipated due to approximately $25.0 million of higher natural gas, freight, and raw material costs, primarily due to an unprecedented, short-term spike in natural gas prices in Europe.

2020 vs. 2019

The 7% decrease in net sales was attributable to a 4% decrease in sales volume, due to COVID-19 impacts, as well as a 3% decrease in pricing from the pass through of lower raw material costs.

Adjusted EBITDA increased by $3.2 million, or 10%, compared to the prior year. This increase was primarily due to a $4.2 million, or 13%, increase in margins, primarily due to commercial excellence pricing actions. Also contributing to the increase was a $0.8 million, or 2%, increase due to lower fixed costs. These effects were partially offset by a decrease of $3.0 million, or 10%, from lower sales volume.

​

Latex Binders Segment

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended ​ ​ ​ ​ ​

​ ​ December 31, ​ ​ Percentage Change ​ ​

Adjusted EBITDA margin ​ 9 % ​ 10 % ​ 8 % ​ ​ ​ ​ ​ ​

2021 vs. 2020

The 54% increase in net sales was primarily due to a 46% increase in pricing from the pass through of raw material costs, mainly styrene and butadiene. Additionally, there was an increase of 6% due to increased sales volume for the

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period, which was driven by higher sales to CASE and paper applications, noting that sales volume to CASE applications alone increased 21% in comparison to prior year.

The $29.9 million, or 39%, increase in Adjusted EBITDA was primarily due to an increase of $22.4 million, or 29%, in sales volume as discussed above. The increase was also due to higher margins of $15.4 million, or 20%, including impacts from commercial excellence initiatives. These effects were partially offset by a decrease of $11.4 million, or 15%, due to higher fixed costs.

2020 vs. 2019

Of the 15% decrease in net sales, 15%, or nearly all of the decrease, was due to lower pricing from the pass through of lower raw material costs.

Adjusted EBITDA remained consistent year over year, with a minor decrease of $0.1 million driven by several offsetting factors. There was a decrease of $6.4 million, or 8%, from a negative net timing variance as well as a decrease of $2.0 million, or 3%, from lower volume and a decrease of $1.6 million, or 2%, due to higher fixed costs. These decreases were partially offset by an increase of $6.4 million, or 8%, mainly due to improved portfolio and product mix, as well as commercial excellence actions, and an increase of $4.2 million, or 5%, attributable to lower freight and utility costs.

Base Plastics Segment

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended ​ ​ ​ ​ ​

​ ​ December 31, ​ ​ Percentage Change ​ ​

Adjusted EBITDA margin ​ 21 % ​ 12 % ​ 9 % ​ ​ ​ ​ ​ ​

2021 vs. 2020

Of the 63% increase in net sales, 53% was due to higher pricing from the pass through of raw material costs, primarily styrene. Additionally, there was a 7% increase due to higher sales volumes, mainly to building and construction applications, and a 3% increase due to favorable foreign exchange rate impacts.

The $208.2 million, or 196%, increase in Adjusted EBITDA was primarily due to higher margins, which contributed $167.3 million, or 158%, particularly in ABS and PC products attributable to commercial excellence initiatives as well as tight supply and strong demand. There was an additional increase of $26.0 million, or 25%, due to increased volumes as discussed above as well as an increase of $12.5 million, or 12%, due to foreign exchange rate impacts.

2020 vs. 2019

Of the 21% decrease in net sales, 12% was due to lower sales volume, primarily related to lower sales to automotive applications from COVID-19 impacts, and 10% was due to lower pricing from the pass through of lower raw material costs.

Adjusted EBITDA increased by $7.3 million, or 7%, compared to the prior year. This increase was due to a $32.0 million, or 32%, increase in margins as a result of favorable pricing actions and tighter market conditions in the second

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half of the year. An additional $10.4 million, or 11%, increase was due to lower fixed costs. These effects were partially offset by lower sales volume of $34.3 million, or 35%.

Polystyrene Segment

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended ​ ​ ​ ​ ​

​ ​ December 31, ​ ​ Percentage Change ​ ​

Adjusted EBITDA margin ​ 16 % ​ 11 % ​ 7 % ​ ​ ​ ​ ​ ​

2021 vs. 2020

Of the 60% increase in net sales, 65% was due to higher pricing primarily from the pass through of higher styrene costs to our customers. This increase was slightly offset by decreased sales volume of 5% caused by raw material constraints and a planned production outage as well as higher demand in the prior year for COVID-19 essential applications such as packaging.

The $103.7 million, or 131%, increase was due to higher margins resulting from commercial excellence initiatives and tight market conditions, which resulted in an increase of $119.5 million, or 150%. These effects were partially offset by a decrease of $8.1 million, or 10%, from lower sales volume as noted above as well as higher fixed costs resulting in a decrease of $5.9 million, or 7%.

2020 vs. 2019

Of the 14% decrease in net sales, 19% was due to lower pricing from the pass through of lower styrene costs to our customers. This was partially offset by an increase of 4% due to increased sales volume.

Adjusted EBITDA increased by $25.0 million, or 46%, compared to the prior year. Higher margins, primarily from pricing initiatives and tighter market conditions, resulted in a $22.4 million, or 41%, increase. Also contributing to the increase was a $6.3 million, or 12%, increase in sales volume.

Feedstocks Segment

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended ​ ​ ​ ​ ​

​ ​ December 31, ​ ​ Percentage Change ​ ​

Adjusted EBITDA ​ $ 33.7 ​ ​ $ 3.2 ​ ​ $ 6.5 ​ ​ 953 % (51) % ​

Adjusted EBITDA margin ​ 12 % ​ 2 % ​ 2 % ​ ​ ​ ​ ​ ​

2021 vs. 2020

Of the 65% increase in net sales, 74% was due to higher pricing from the pass through of higher styrene prices. This effect was partially offset by a 10% decrease due to lower styrene-related sales volume.

The increase of $30.5 million in Adjusted EBITDA was primarily due to higher styrene margins in Europe, despite significantly higher utility costs from high natural gas prices, resulting in an increase of $41.3 million. This effect was

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partially offset by negative impacts of $7.8 million due to foreign exchange rates as well as $2.2 million due to higher fixed costs.

2020 vs. 2019

Of the 44% decrease in net sales, 25% was due to lower styrene-related sales volume and 19% was due to lower pricing from the pass through of lower styrene prices.

Adjusted EBITDA decreased by $3.3 million, or 51%, compared to the prior year. Lower margins resulted in a $4.8 million, or 74%, decrease due to unfavorable net timing and portfolio mix. An additional 52% decrease was attributable to currency impacts. These decreases were partially offset by lower fixed costs driven by the Company’s overall cost reduction initiatives, which resulted in a 61% increase.

Americas Styrenics Segment

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended ​ ​ ​ ​ ​

​ ​ December 31, ​ ​ Percentage Change ​ ​

*The results of this segment are comprised entirely of earnings from Americas Styrenics, our equity method investment. As such, Adjusted EBITDA related to this segment is included within “Equity in earnings of unconsolidated affiliates” in the consolidated statements of operations.

2021 vs. 2020

The increase in Adjusted EBITDA was mainly due to increased polystyrene sales volume and higher styrene and polystyrene margins in North America, primarily attributable to COVID-19 related impacts in the prior year as well as tight supply conditions caused by weather related and other events.

2020 vs. 2019

The 44% decrease in Adjusted EBITDA was mainly due to lower styrene margins in North America, volume-related impacts from COVID-19, and the impact from the planned turnaround at its St. James, Louisiana styrene facility in the first quarter of 2020.

Outlook

Based on the strong demand in many of our end markets, as well as our commercial excellence programs and the synergies from our acquired businesses, we expect that 2022 will be another year of solid earnings and strong cash generation. As discussed above in “2021 Highlights,” there were challenges in late 2021 due to high energy prices and adverse supply chain and production conditions, however, we have navigated through these situations and have successfully continued providing unique product solutions to our customers. We will continue to move forward with our transformation strategy, including progressing on our process to divest the styrenics businesses, and achieving our sustainability goals.

Non-GAAP Performance Measures

We present Adjusted EBITDA as a non-GAAP financial performance measure, which we define as income from continuing operations before interest expense, net; provision for income taxes; depreciation and amortization expense; loss on extinguishment of long-term debt; asset impairment charges; gains or losses on the dispositions of businesses and assets; restructuring charges; acquisition related costs and other items. In doing so, we are providing management,

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investors, and credit rating agencies with an indicator of our ongoing performance and business trends, removing the impact of transactions and events that we would not consider a part of our core operations.

There are limitations to using the financial performance measures such as Adjusted EBITDA. This performance measure is not intended to represent net income or other measures of financial performance. As such, it should not be used as an alternative to net income as an indicator of operating performance. Other companies in our industry may define Adjusted EBITDA differently than we do. As a result, it may be difficult to use this or similarly-named financial measures that other companies may use, to compare the performance of those companies to our performance. We compensate for these limitations by providing a reconciliation of this performance measure to our net income, which is determined in accordance with accounting principles generally accepted in the United States of America (“GAAP”).

Adjusted EBITDA is calculated as follows for the years ended December 31, 2021, 2020, and 2019. Prior period amounts herein have been recast in conjunction with adjustments made for the Company’s classification of the Synthetic Rubber business as discontinued operations.

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended ​

​ ​ December 31,

Net income (loss) from discontinued operations ​ ​ 160.4 ​ ​ (54.8) ​ ​ 4.9 ​

Net income from continuing operations ​ ​ 279.6 ​ ​ 62.7 ​ ​ 87.1 ​

Provision for income taxes ​ 70.9 ​ 42.7 ​ 12.7 ​

Depreciation and amortization ​ 167.5 ​ 92.6 ​ 91.5 ​

Net gain on disposition of businesses and assets ​ ​ (0.6) ​ ​ (0.4) ​ (0.7) ​

Restructuring and other charges(b) ​ ​ 9.0 ​ ​ 5.6 ​ 16.8 ​

Acquisition purchase price hedge loss (gain)(d) ​ ​ 22.0 ​ ​ (7.3) ​ ​ — ​

Asset impairment charges or write-offs(e) ​ ​ 6.8 ​ ​ 11.0 ​ ​ — ​

Note that the accelerated depreciation charges incurred as part of both the Company’s corporate restructuring program and the upgrade and replacement of the Company’s compounding facility in Terneuzen, The Netherlands are included within the “Depreciation and amortization” caption above, and therefore are not included as a separate adjustment within this caption.

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Liquidity and Capital Resources

Cash Flows

The table below summarizes our primary sources and uses of cash for the years ended December 31, 2021, 2020, and 2019. We have derived the summarized cash flow information from our audited financial statements. Prior period amounts herein have been recast in conjunction with adjustments made for the Company’s classification of the Synthetic Rubber business as discontinued operations, as described in Note 5 of the consolidated financial statements and in Item 1—Business.

​

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended

​ ​ December 31,

Net cash provided by (used in): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Operating activities - continuing operations ​ $ 456.0 ​ $ 216.8 ​ $ 241.9 ​

Operating activities - discontinued operations ​ ​ (3.3) ​ ​ 38.6 ​ ​ 80.6 ​

Investing activities - continuing operations ​ (1,936.2) ​ (3.0) ​ (83.2) ​

Investing activities - discontinued operations ​ ​ 396.5 ​ ​ (21.2) ​ ​ (26.1) ​

Effect of exchange rates on cash ​ (4.4) ​ 4.4 ​ (1.4) ​

Operating Activities

Net cash provided by operating activities from continuing operations during the year ended December 31, 2021 totaled $456.0 million, driven by strong earnings, and inclusive of dividends received from Americas Styrenics of $85.0 million. Partially offsetting these factors was a $23.0 million reduction in operating cash from a net working capital use during the period, primarily attributable to increases in raw material costs. Net cash used in operating activities from discontinued operations during the year ended December 31, 2021 totaled $3.3 million, and was related to the operations of our Synthetic Rubber business, which was sold during the period. As discussed in Note 5 to the consolidated financial statements, the sale of our Synthetic Rubber business excluded the transfer of net working capital (excluding inventory).

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As a result, the release of this working capital, the majority of which will occur in the first quarter of 2022, is or will be included in our continuing operating cash flows.

Net cash provided by operating activities from continuing operations during the year ended December 31, 2020 totaled $216.8 million. This increase in cash was driven by a $83.6 million increase in operating cash generated from a net working capital release during the period, which was primarily attributable to the Company’s liquidity-focused actions during the height of the COVID-19 pandemic, including reduced capital spending, operating expenses, and working capital, as well as the impact of lower raw material prices and sales volumes. Net cash provided by operating activities from discontinued operations during the year ended December 31, 2020 totaled $38.6 million, and was also driven by the aforementioned liquidity-focused actions.

Net cash provided by operating activities from continuing operations during the year ended December 31, 2019 totaled $241.9 million, inclusive of $110.0 million of dividends received from Americas Styrenics. This increase in cash was driven by a $98.6 million increase in operating cash generated from a net working capital release during the period, which was primarily attributable to decreases of $66.6 million in accounts receivable and $43.1 million in inventories, due to lower raw material prices and lower sales volumes, as well as lower days sales in inventory. Net cash provided by operating activities from discontinued operations during the year ended December 31, 2019 totaled $80.6 million, and was also driven by lower raw material prices and lower sales volumes during the period.

Investing Activities

Net cash used in investing activities from continuing operations during the year ended December 31, 2021 totaled $1,936.2 million, which was primarily attributable to net cash paid for asset or business acquisitions of $1,804.0 million (see Note 4), capital expenditures of $117.7 million, and payments for the settlement of hedging instruments of $14.7 million (related to the acquisition purchase price hedge – see Note 13). Net cash provided by investing activities from discontinued operations during the year ended December 31, 2021 totaled $396.5 million, which was primarily attributable to cash received from the sale of the Synthetic Rubber business.

Capital expenditures for 2022 are expected to be approximately $180.0 million, inclusive of spending for both growth initiatives as well as compliance and maintenance costs.

Net cash used in investing activities from continuing operations during the year ended December 31, 2020 totaled $3.0 million. This activity included capital expenditures of $66.6 million, partially offset by proceeds from the settlement of hedging instruments of $51.6 million as well as proceeds of $11.9 million from the sale of our former latex binders manufacturing facility in Livorno, Italy. Net cash used in investing activities from discontinued operations during the year ended December 31, 2020 totaled $21.2 million, which was attributable to capital expenditures of $15.7 million as well as cash paid for a cost method investment of $5.5 million.

Net cash used in investing activities from continuing operations during the year ended December 31, 2019 totaled $83.2 million, primarily resulting from capital expenditures of $84.0 million. Net cash used in investing activities from discontinued operations during the year ended December 31, 2019 totaled $26.1 million, which was entirely attributable to capital expenditures.

Financing Activities

Net cash provided by financing activities during the year ended December 31, 2021 totaled $1,075.7 million. This activity was primarily due to $746.3 million in proceeds from the issuance of the 2028 Term Loan B, $450.0 million in proceeds from the issuance of the 2029 Senior Notes, and $11.0 million in proceeds from exercise of option awards. This activity was partially offset by $48.1 million of ordinary share repurchases, $35.4 million of deferred financing fees paid, $14.6 million of net repayments of short-term borrowings, $21.9 million of dividend payments, and $10.7 million of net principal payments related to our 2024 Term Loan B and 2028 Term Loan B during the period.

Net cash used in financing activities during the year ended December 31, 2020 totaled $104.3 million. This activity was primarily due to $61.8 million of dividends paid, $25.0 million of payments related to the repurchase of ordinary shares, $12.6 million net repayments of short-term borrowings, and $6.9 million of net principal payments related to our 2024 Term Loan B during the period. Additionally, net cash used in financing activities included $0.6 million of withholding taxes paid related to the vesting of certain Restricted Share Units (“RSUs”) during the period, which was more than offset by $2.6 million of proceeds received from the exercise of option awards.

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Net cash used in financing activities during the year ended December 31, 2019 totaled $206.7 million. This activity was primarily due to $119.7 million of ordinary shares repurchases, $65.7 million of dividends paid, $7.0 million of net principal payments related to our 2024 Term Loan B during the period, and $10.6 million net repayments of short-term borrowings. Additionally, net cash used in financing activities included $4.6 million of withholding taxes paid related to the vesting of certain RSUs during the period, partially offset by $0.9 million of proceeds received from the exercise of option awards.

​

Free Cash Flow

We use Free Cash Flow as a non-GAAP measure to evaluate and discuss the Company’s liquidity position and results. Free Cash Flow is defined as cash from operating activities, less capital expenditures. We believe that Free Cash Flow provides an indicator of the Company’s ongoing ability to generate cash through core operations, as it excludes the cash impacts of various financing transactions as well as cash flows from business combinations that are not considered organic in nature. We also believe that Free Cash Flow provides management and investors with useful analytical indicator of our ability to service our indebtedness, pay dividends (when declared), and meet our ongoing cash obligations.

Free Cash Flow is not intended to represent cash flows from operations as defined by GAAP, and therefore, should not be used as an alternative for that measure. Other companies in our industry may define Free Cash Flow differently than we do. As a result, it may be difficult to use this or similarly-named financial measures that other companies may use, to compare the liquidity and cash generation of those companies to our own. We compensate for these limitations by providing a reconciliation to cash provided by operating activities, which is determined in accordance with GAAP.

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended ​

​ ​ December 31, ​

Cash provided by operating activities ​ $ 452.7 ​ $ 255.4 ​ $ 322.5 ​

Capital expenditures ​ ​ (123.5) ​ ​ (82.3) ​ ​ (110.1) ​

Refer to the discussion above for significant impacts to cash provided by operating activities for the years ended December 31, 2021, 2020, and 2019.

​

Capital Resources, Indebtedness and Liquidity

We require cash principally for day-to-day operations, to finance capital investments and other initiatives, to purchase materials, to service our outstanding indebtedness, and to fund the return of capital to shareholders via dividend payments and ordinary share repurchases, when deemed appropriate. Our sources of liquidity include cash on hand, cash flow from continuing operations, and amounts available under the Senior Credit Facility and the Accounts Receivable Securitization Facility (discussed further below).

As of December 31, 2021 and 2020, we had $2,368.8 million and $1,187.3 million, respectively, in outstanding indebtedness and $1,064.1 million and $983.3 million, respectively, in working capital (calculated as current assets from continuing operations less current liabilities from continuing operations). In addition, as of December 31, 2021 and 2020, we had $560.6 million and $172.8 million, respectively, of foreign cash and cash equivalents on our consolidated balance sheets, outside of our country of domicile, which was Ireland as of December 31, 2021 and Luxembourg as of December 31, 2020, all of which is readily convertible into other foreign currencies, including the U.S. dollar. Our intention is not to permanently reinvest our foreign cash and cash equivalents. Accordingly, we record deferred income tax liabilities related to the unremitted earnings of our subsidiaries. For a detailed description of the Company’s debt structure, borrowing rates, and expected future payment obligations, refer to Note 12 in the consolidated financial statements.

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The following table outlines our outstanding indebtedness as of December 31, 2021 and 2020 and the associated interest expense, including amortization of deferred financing fees and issuance discounts. Effective interest rates for the borrowings included in the table below exclude the impact of deferred financing fee amortization, certain other fees charged to interest expense (such as fees for unused commitment fees during the period), and the impacts of derivatives designated as hedging instruments.

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ As of and for the Year Ended ​ As of and for the Year Ended

​ ​ ​ ​ Effective ​ ​ ​ ​ ​ Effective ​ ​

​ ​ ​ ​ Interest ​ Interest ​ ​ ​ Interest ​ Interest

($ in millions) Balance Rate Expense Balance ​ Rate Expense

Senior Credit Facility ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

2026 Revolving Facility ​ ​ — ​ — % ​ 2.1 ​ ​ — ​ — ​ ​ 3.7 ​

Accounts Receivable Securitization Facility ​ — ​ 2.0 % 1.8 ​ — ​ — ​ 1.5 ​

Other indebtedness* ​ 5.6 ​ 2.2 % — ​ 10.0 ​ 2.4 % 0.1 ​

*For the year ended December 31, 2021, interest expense on “Other indebtedness” totaled less than $0.1 million.

Our Senior Credit Facility includes the 2026 Revolving Facility, which matures in May 2026 and has a borrowing capacity of $375.0 million. As of December 31, 2021, the Company had $368.6 million of funds available for borrowing (net of $6.4 million outstanding letters of credit) under the 2026 Revolving Facility. Further, as of December 31, 2021, the Company is required to pay a quarterly commitment fee in respect of any unused commitments under the 2026 Revolving Facility equal to 0.375% per annum.

Also included in our Senior Credit Facility is our 2024 Term Loan B (with original principal of $700.0 million, maturing in September 2024), and our 2028 Term Loan B (with original principal of $750.0 million, maturing in May 2028), each of which requires scheduled quarterly payments in amounts equal to 0.25% of the original principal. The stated interest rate on our 2024 Term Loan B is London Interbank Offered Rate (“LIBOR”) plus 2.00% (subject to a 0.00% LIBOR floor). The stated interest rate on our 2028 Term Loan B is LIBOR plus 2.50% (subject to a 0.00% LIBOR floor). The Company made net principal payments of $7.0 million on the 2024 Term Loan B and net principal payments of $3.7 million on the 2028 Term Loan B during the year ended December 31, 2021, with an additional $14.5 million of scheduled future payments classified within current debt on the Company’s consolidated balance sheet as of December 31, 2021 related to both the 2024 Term Loan B and 2028 Term Loan B.

Our 2025 Senior Notes issued under the indenture executed in 2017 include $500.0 million aggregate principal amount of 5.375% senior notes that mature on September 1, 2025. Interest on the 2025 Senior Notes is payable semi-annually on May 3 and November 3 of each year. These Notes may be redeemed prior to their maturity at the option of the Company under certain circumstances at specific redemption prices. Refer to Note 12 in the consolidated financial statements for further information.

Our 2029 Senior Notes, as issued under the indenture executed in 2021, include $450.0 million aggregate principal amount of 5.125% senior notes that mature on April 1, 2029. Interest on the 2029 Senior Notes is payable semi-annually on February 15 and August 15 of each year, which commenced on August 15, 2021. These Notes may be redeemed prior to their maturity at the option of the Company under certain circumstances at specific redemption prices. Refer to Note 12 in the consolidated financial statements for further information.

We also continue to maintain our Accounts Receivable Securitization Facility, which has an outstanding borrowing capacity of $150.0 million. The Accounts Receivable Securitization Facility was amended during 2021, and pursuant to the amended terms, it matures in November 2024 and incurs fixed interest charges of 1.65% on outstanding borrowings plus variable commercial paper rates, as well as fixed charges of 0.80% on available, but undrawn commitments. In August 2021, in conjunction with the Aristech Surfaces Acquisition, we drew $150.0 million on our

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Accounts Receivable Securitization Facility, which was fully repaid as of December 31, 2021. As such, as of December 31, 2021, there were no amounts outstanding under this facility and the Company had approximately $150.0 million of accounts receivable available to support this facility, based on the pool of eligible accounts receivable.Refer to Note 12 in the consolidated financial statements for further information on the facility.

Our ability to raise additional financing and our borrowing costs may be impacted by short- and long-term debt ratings assigned by independent rating agencies, which are based, in significant part, on our performance as measured by certain credit metrics such as interest coverage and leverage ratios.

We and our subsidiaries, affiliates, or significant shareholders may from time to time seek to retire or purchase our outstanding debt through cash purchases in the open market, privately negotiated transactions, exchange transactions or otherwise. Such repurchases or exchanges, if any, will depend on prevailing market conditions, our liquidity requirements, contractual restrictions and other factors. The amounts involved may be material.

Trinseo Materials Operating S.C.A. and Trinseo Materials Finance, Inc. (the “Issuers” of our 2029 Senior Notes and 2025 Senior Notes and “Borrowers” under our Senior Credit Facility) are dependent upon the cash generation and receipt of distributions and dividends or other payments from our subsidiaries and joint venture in order to satisfy their debt obligations. There are no known significant restrictions by third parties on the ability of subsidiaries of the Company to disburse or dividend funds to the Issuers and the Borrowers in order to satisfy these obligations. However, as the Company’s subsidiaries are located in a variety of jurisdictions, the Company can give no assurances that our subsidiaries will not face transfer restrictions in the future due to regulatory or other reasons beyond our control.

The Senior Credit Facility and Indentures also limit the ability of the Borrowers and Issuers, respectively, to pay dividends or make other distributions to Trinseo PLC, which could then be used to make distributions to shareholders. During the year ended December 31, 2021, the Company declared total dividends of $0.80 per ordinary share, or $31.4 million, of which $13.6 million, inclusive of dividend equivalents, remains accrued as of December 31, 2021 and the majority of which was paid in January 2022. These dividends are well within the available capacity under the terms of the restrictive covenants contained in the Senior Credit Facility and Indentures. Further, significant additional capacity continues to be available under the terms of these covenants to support expected future dividends to shareholders, should the Company continue to declare them.

The Company’s cash flow generation in recent years has been strong, and the Company generated positive cash flows during the year ended December 31, 2021. We believe that funds provided by operations, our existing cash, cash equivalent, and restricted cash balances, borrowings available under our 2026 Revolving Facility and our Accounts Receivable Securitization Facility will be adequate to meet planned operating and capital expenditures for at least the next 12 months under current operating conditions.

Our ability to generate cash from operations to pay our indebtedness and meet other liquidity needs is subject to certain risks described herein and under Item 1A—Risk Factors. As of December 31, 2021, we were in compliance with all the covenants and default provisions under our debt agreements. Refer to Note 12 in the consolidated financial statements for further information on the details of the covenant requirements.

We do not have any off-balance sheet financing arrangements that we believe are reasonably likely to have a material current or future effect on our financial condition, revenues or expenses, results of operations, liquidity, capital expenditures or capital resources.

Contractual Obligations and Commercial Commitments

The Company’s primary contractual obligations and commercial commitments consist of the payments for principal and interest on our outstanding long-term debt, raw material purchases, funding requirements under our pension and other postretirement benefits, lease commitments, and obligations under our SAR SSAs.

The Company has both fixed and variable-rate long-term debt arrangements, which have varying principal and interest payment requirements over their contractual terms. Refer to the table and section above as well as to Note 12 in the consolidated financial statements for more information on our debt arrangements. Additionally, refer to Item 7A—

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Quantitative and Qualitative Disclosures about Market Risk for discussion of our interest rate and foreign currency risks related to our debt and debt-related hedging arrangements.

The Company has certain raw material purchase contracts where we are required to purchase certain minimum volumes at the then prevailing market prices. As of December 31, 2021, the Company had $2,078.2 million of raw material purchase obligations, of which $859.1 million is due within the next twelve months. These commitments have remaining terms ranging from one to five years. Refer to Note 16 in the consolidated financial statements for more information on raw material purchase commitments. Additionally, refer to Item 1 – Business – Sources and Availability of Raw Materials for further description of the sources of our key raw materials.

The Company has various pension and other postretirement plans. The Company is required to make minimum contributions to certain of our funded pension plans and is also obligated to make benefit payments to employees for the unfunded pension plans and other postretirement plans. As of December 31, 2021, the Company’s estimated future benefit payments through 2031, reflecting expected future service, as appropriate, was $137.5 million, of which $9.7 million is due within the next twelve months. Refer to the section of our Critical Accounting Policies and Estimates entitled “Pension Plans and Postretirement Benefits” for more information on the factors impacting our pension and postretirement costs. Additionally, refer to Note 17 in the consolidated financial statements for more details on these employee benefit plans and the future payments expected to be made for them through 2031.

The Company has operating and finance leases for certain of its plant and warehouse sites, office spaces, rail cars, storage facilities, and equipment. The Company’s leases have remaining terms of one month through fourteen years. As of December 31, 2021, the Company’s estimated minimum commitments related to our finance and operating lease obligations was $103.1 million, of which $23.1 million is due within the next twelve months. Refer to Note 24 in the consolidated financial statements for further information on our lease portfolio and future lease obligations.

As described in Item 1— Business— Our Relationship with Dow, the Company is party to SAR SSAs with Dow, which are agreements under which Dow provides certain site services to the Company at Dow-owned locations. Based on our current year known costs and assuming that we continue with the SAR SSAs with similar annualized costs going forward, we estimate our contractual obligations under these agreements to be approximately $210.3 million annually for 2022 through 2026, and a total of $2,622.5 million thereafter through June 2039. Refer to the aforementioned section of Item 1 for more information regarding these agreements, including details regarding the rights of the Company and Dow to terminate said agreements.

Derivative Instruments

The Company’s ongoing business operations expose it to various risks, including fluctuating foreign exchange rates and interest rate risk. To manage this risk, the Company periodically enters into derivative financial instruments, such as foreign exchange forward contracts and interest rate swap agreements. A summary of these derivative financial instrument programs is described below; however, refer to Note 13 of the consolidated financial statements for further information. The Company does not hold or enter into financial instruments for trading or speculative purposes.

Foreign Exchange Forward Contracts

Certain subsidiaries have assets and liabilities denominated in currencies other than their respective functional currencies, which creates foreign exchange risk. Our principal strategy in managing exposure to changes in foreign currency exchange rates is to naturally hedge the foreign currency-denominated liabilities on our consolidated balance sheets against corresponding assets of the same currency such that any changes in liabilities due to fluctuations in exchange rates are offset by changes in their corresponding foreign currency assets. In order to further reduce our exposure, the Company uses foreign exchange forward contracts to economically hedge the impact of the variability in exchange rates on our assets and liabilities denominated in certain foreign currencies. These derivative contracts are not designated for hedge accounting treatment.

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Foreign Exchange Cash Flow Hedges

The Company also enters into forward contracts with the objective of managing the currency risk associated with forecasted U.S. dollar-denominated raw materials purchases by one of our subsidiaries whose functional currency is the euro. By entering into these forward contracts, which are designated as cash flow hedges, the Company buys a designated amount of U.S. dollars and sells euros at the prevailing market rate to mitigate the risk associated with the fluctuations in the euro-to-U.S. dollar foreign currency exchange rate.

Interest Rate Swaps

The Company enters into interest rate swap agreements to manage our exposure to variability in interest payments associated with the Company’s variable rate debt. Under these interest rate swap agreements, which are designated as cash flow hedges, the Company is effectively converting a portion of our variable rate borrowings into a fixed rate obligation to mitigate the risk of variability in interest rates.

Net Investment Hedge

The Company has certain fixed-for-fixed cross currency swaps (“CCS”), swapping U.S. dollar principal and interest payments on our 2025 Senior Notes for euro-denominated payments, which were designated as a hedge of the Company’s net investment in certain European subsidiaries under the forward method through March 31, 2018 through the original CCS agreement entered into on September 1, 2017 (“2017 CCS”). As such, changes in their fair value, to the extent effective, were recorded within the cumulative translation adjustment account as a component of accumulated other comprehensive income or loss (“AOCI”) through March 31, 2018.

Effective April 1, 2018, in conjunction with the adoption of previously issued hedging accounting guidance, the Company elected as an accounting policy to re-designate the 2017 CCS as a net investment hedge (and any future similar hedges) under the spot method. As such, changes in the fair value of the 2017 CCS that were included in the assessment of effectiveness (changes due to spot foreign exchange rates) were recorded as cumulative foreign currency translation within AOCI, and will remain in AOCI until either the sale or substantially complete liquidation of the subsidiary. As an additional accounting policy election applied to similar hedges under this standard, the initial value of any component excluded from the assessment of effectiveness is recognized in income using a systematic and rational method over the life of the hedging instrument. Any difference between the change in the fair value of the excluded component and amounts recognized in income under that systematic and rational method is recognized in AOCI. The Company elected to amortize the initial excluded component value as a reduction of “Interest expense, net” in the consolidated statements of operations using the straight-line method over the remaining term of the 2017 CCS. Additionally, the Company recognizes the accrual of periodic USD and euro-denominated interest receipts and payments under the terms of CCS arrangements, including the 2017 CCS, within “Interest expense, net” in the consolidated statements of operations.

On February 26, 2020, the Company settled our 2017 CCS and replaced it with a new CCS arrangement (the “2020 CCS”) that carried substantially the same terms as the 2017 CCS and also is designated as a net investment hedge under the spot method. Upon settlement of the 2017 CCS, the Company realized net cash proceeds of $51.6 million. The remaining $13.8 million unamortized balance of the initial excluded component related to the 2017 CCS at the time of settlement is no longer being amortized following the settlement and will remain in AOCI until either the sale or substantially complete liquidation of the relevant subsidiaries.

Critical Accounting Policies and Estimates

Our discussion and analysis of results of operations and financial condition are based upon our financial statements, which have been prepared in accordance with GAAP. The preparation of these financial statements requires us to make estimates and judgments that affect the amounts reported. We base these estimates and judgments on historical experiences and assumptions believed to be reasonable under the circumstances. Actual results could vary from our estimates under different conditions. Our significant accounting policies, which may be affected by our estimates and assumptions, are more fully described in Note 2 in the consolidated financial statements. An accounting policy is deemed to be critical if it requires an accounting estimate to be made based on assumptions about matters that are highly uncertain at the time the estimate is made, and if different estimates that reasonably could have been used, or changes in the accounting estimates that are reasonably likely to occur periodically, could materially impact the financial

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statements. The following critical accounting policies reflect our most significant estimates and assumptions used in the preparation of the consolidated financial statements.

Business Combinations and Asset Impairments

Business Combinations

Acquisitions that qualify as a business combination are accounted for using the purchase accounting method. Amounts paid for an acquisition are allocated to the assets acquired and liabilities assumed based on their fair value as of the date of acquisition. Goodwill is recorded as the difference between the fair value of the acquired assets and liabilities assumed (net assets acquired) and the purchase price. Goodwill is not amortized, but is reviewed for impairment annually as of October 1, or when events or changes in the business environment indicate that the carrying value of a reporting unit may exceed its fair value. Refer to the discussion below for further information on asset impairments.

Under the purchase accounting method, the Company completes valuation procedures for an acquisition, often with the assistance of third-party valuation specialists, to determine the fair value of the assets acquired and liabilities assumed. These valuation procedures require management to make assumptions and apply significant judgment to estimate the fair value of the assets acquired and liabilities assumed. If the estimates or assumptions used should significantly change, the resulting differences could materially affect the fair value of net assets.

Specifically, the calculation of the fair value of tangible assets, including property, plant and equipment, typically utilize the cost approach, which computes the cost to replace the asset, less accrued depreciation resulting from physical deterioration and functional and external obsolescence. The calculation of the fair value of identified intangible assets is determined using cash flow models following the income and cost approaches (or some combination thereof). Significant inputs include estimated future cash flows, discount rates, royalty rates, growth rates, sales projections, customer retention rates, and terminal values, all of which require significant management judgment. Definite-lived intangible assets, which are primarily comprised of customer relationships, developed technology, tradenames, and software, are amortized over their estimated useful lives using the straight-line method and are assessed for impairment whenever events or changes in circumstances indicate the carrying value of the asset may not be recoverable.

During the year ended December 31, 2021, the Company completed two significant acquisitions: the PMMA Acquisition, closed on May 3, 2021, and the Aristech Surfaces Acquisition, closed on September 1, 2021. Also, the Company completed the divestiture of our Synthetic Rubber business on December 1, 2021. Refer to Notes 4 and 5 in the consolidated financial statements for further information on these transactions.

Asset Impairments

As of December 31, 2021, net property, plant and equipment, net identifiable finite-lived intangible assets, and goodwill totaled $719.0 million, $823.8 million, and $710.1 million, respectively. Management makes estimates and assumptions in preparing the consolidated financial statements for which actual results will emerge over long periods of time. This includes the recoverability of long-lived assets employed in the business. These estimates and assumptions are closely monitored by management and periodically adjusted as circumstances warrant. For instance, expected asset lives may be shortened or impairment may be recorded based on a change in the expected use of the asset or performance of the related asset group.

We evaluate long-lived assets and identifiable finite-lived intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset grouping may not be recoverable. In the event the carrying value of the asset exceeds its undiscounted future cash flows and the carrying value is not considered recoverable, impairment may exist. An impairment loss, if any, is measured as the excess of the asset’s carrying value over its fair value, generally based on a discounted future cash flow method, independent appraisals, etc.

In connection with our strategy to focus efforts and increase investments in certain product offerings serving specific applications that are less cyclical and offer significantly higher growth and margin potential, and other management considerations, in March of 2020, the Company initiated a consultation process with the Economic Council and Works Councils of Trinseo Deutschland regarding the disposition of our styrene monomer assets in Boehlen, Germany and our PBR assets in Schkopau, Germany. The Company’s assessments of these long-lived asset groups for impairment indicated that the carrying values of the asset groups at each location were not recoverable when compared to the expected undiscounted future cash flows from the operation and potential disposition of these assets. The fair

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value of the depreciable assets at each location was determined through an analysis of the underlying fixed asset records in conjunction with the use of industry experience and available market data. Based on the Company’s assessments, for the years ended December 31, 2021 and 2020, we recorded impairment charges on the Boehlen styrene monomer assets of $5.8 million and $11.1 million, respectively, which include charges recorded subsequent to March 2020 related to capital expenditures at the facility that we determined to be impaired. The amounts are included within “Impairment charges” in the consolidated statements of operations and are all allocated to the Feedstocks segment.

During the year ended December 31, 2020, we also recorded impairment charges of $28.0 million on the Schkopau PBR assets which are allocated to the Synthetic Rubber business. As discussed below, during the second quarter of 2021 these assets were classified as held-for-sale and their operating results were classified as discontinued operations for all periods presented, along with the rest of the Synthetic Rubber business.

Through December 31, 2021, we have continued to assess the recoverability of certain assets, and concluded there are no additional significant events or circumstances identified by management that would indicate these assets are not recoverable. However, the current environment is subject to changing market conditions and requires significant management judgment to identify the potential impact to our assessment. If we are not able to achieve certain actions or our future operating results do not meet our expectations, it is possible that impairment charges may need to be recorded on one or more of our operating facilities.

Long-lived assets to be disposed of by sale are classified as held-for-sale and are reported at the lower of carrying amount or fair value less cost to sell, and depreciation is ceased. Long-lived assets to be disposed of in a manner other than by sale are classified as held-and-used until they are disposed. In May 2021, the Company entered into an agreement to sell our Synthetic Rubber business, as a result of which the assets and liabilities of the Synthetic Rubber business were classified as held-for-sale in the consolidated balance sheets starting in the second quarter of 2021, and have been reflected as such for all periods presented until their disposal. The sale transaction was completed in December 2021, thus as of December 31, 2021 these assets and liabilities are no longer held-for-sale. Additionally, starting in the second quarter of 2021, the operating results of the Synthetic Rubber business, net of taxes, have been classified as discontinued operations in the consolidated statements of operations for all periods presented. Refer to Note 5 for more information.

As noted above, our goodwill impairment testing is performed annually as of October 1 at a reporting unit level. We perform more frequent impairment tests when events or changes in circumstances indicate that the fair value of a reporting unit has more likely than not declined below its carrying value. As of our annual assessment date of October 1, 2021, each of our reporting units had fair values that exceeded the carrying value of their net assets, indicating that no impairment of goodwill is warranted.

A goodwill impairment loss generally would be recognized when the carrying amount of the reporting unit’s net assets exceeds the estimated fair value of the reporting unit. The estimated fair value of a reporting unit is determined using a market approach and an income approach (under the discounted cash flow method). When supportable, the Company employs the qualitative assessment of goodwill impairment prescribed by Accounting Standards Codification 350. As of December 31, 2021, our $710.1 million in total goodwill is allocated to our reportable segments as follows: $667.3 million to Engineered Materials, $15.9 million to Latex Binders, $22.4 million to Base Plastics, and $4.5 million to Polystyrene, with no amounts allocated to the Feedstocks or Americas Styrenics segments. Of the $667.3 million of goodwill allocated to Engineered Materials, $652.6 million was recorded at fair value on the date of acquisition related to the PMMA business and Aristech Surfaces business acquired in 2021.

Factors which could result in future impairment charges, among others, include changes in worldwide economic conditions, changes in technology, changes in competitive conditions and customer preferences, and fluctuations in foreign currency exchange rates. These factors are discussed in Item 7A—Quantitative and Qualitative Disclosures about MarketRisk and Item 1A— Risk Factors included in this Annual Report.

Income Taxes

We account for income taxes using the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences of temporary differences between the carrying amounts and tax bases of assets and liabilities using enacted rates. The effect of a change in tax rates on deferred taxes is recognized in income in the period that includes the enactment date.

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Deferred taxes are provided on the outside basis differences and unremitted earnings of subsidiaries outside of Ireland. All undistributed earnings of foreign subsidiaries and affiliates are expected to be repatriated as of December 31, 2021. Based on the evaluation of available evidence, both positive and negative, we recognize future tax benefits, such as net operating loss carryforwards and tax credit carryforwards, to the extent that realizing these benefits is considered to be more likely than not.

As of December 31, 2021, we had deferred tax assets of $122.6 million, after valuation allowances of $127.7 million. In evaluating the ability to realize the deferred tax assets, we rely on, in order of increasing subjectivity, taxable income in prior carryback years, the future reversals of existing taxable temporary differences, tax planning strategies and forecasted taxable income using historical and projected future operating results.

Swiss federal and cantonal tax reform was enacted on August 6, 2019 and October 25, 2019, respectively, and includes measures such as, the elimination of certain preferential tax regimes and implementation of new tax rates at both the federal and cantonal levels. It also includes transitional relief measures which may provide for future tax deductions. As a result of both the federal and cantonal law changes, the Company recorded a $65.0 million one-time deferred tax benefit for the year ended December 31, 2019, of which $61.6 million was related to cantonal tax law changes. The Company believes it is more likely than not that a portion of this deferred tax benefit recorded as a result of these cantonal tax law changes will not be realized during the utilization period provided by the legislation, spanning 2025 through 2029. This is based on the Company’s estimate of future taxable income in Switzerland, which was determined using management’s judgment and assumptions about various factors, such as: historical experience and results, cyclicality of the business, implications of COVID-19, recent acquisitions and divestitures, and future industry and macroeconomic conditions and trends possible during the aforementioned utilization period. As a result, the Company recorded a $25.3 million valuation allowance as of December 31, 2019. As of December 31, 2021, due to foreign exchange translation, the total valuation allowance recorded was $25.8 million.

As of December 31, 2021, we had deferred tax assets for tax loss carryforward of approximately $389.4 million, $17.4 million of which is subject to expiration in the years between 2022 and 2027. We continue to evaluate our historical and projected operating results for several legal entities for which we maintain valuation allowances on net deferred tax assets.

We are subject to income taxes in Ireland, the United States and numerous foreign jurisdictions, and are subject to audit within these jurisdictions. Therefore, in the ordinary course of business there is inherent uncertainty in quantifying our income tax positions. The tax provision includes amounts considered sufficient to pay assessments that may result from examinations of prior year tax returns; however, the amount ultimately paid upon resolution of issues raised may differ from the amounts accrued. Since significant judgment is required to assess the future tax consequences of events that have been recognized in our financial statements or tax returns, the ultimate resolution of these events could result in adjustments to our financial statements and such adjustments could be material. Therefore, we consider such estimates to be critical in preparation of our financial statements.

The financial statement effect of an uncertain income tax position is recognized when it is more likely than not, based on the technical merits, that the position will be sustained upon examination. Accruals are recorded for other tax contingencies when it is probable that a liability to a taxing authority has been incurred and the amount of the contingency can be reasonably estimated. Uncertain income tax positions have been recorded in “Other noncurrent obligations” in the consolidated balance sheets for the periods presented.