Ecovyst Inc. 10-Q

ITEM 1. FINANCIAL STATEMENTS (UNAUDITED) ECOVYST INC. AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF INCOME (in thousands, except share and per share amounts) (unaudited) Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Sales $ 200,128 $ 182,820 $ 362,326 $ 343,357 Cost of goods sold 150,406 129,157 286,988 250,471 Gross profit 49,722 53,663 75,338 92,886 Selling, general and administrative expenses 22,661 22,707 44,006 44,310 Other operating expense, net 9,252 3,108 14,433 6,774 Operating income 17,809 27,848 16,899 41,802 Equity in net (income) from affiliated companies ( 1,928 ) ( 1,392 ) ( 10,844 ) ( 3,464 ) Interest expense, net 11,117 12,895 22,127 26,304 Debt modification and extinguishment costs — 4,560 960 4,560 Other expense, net 570 410 755 627 Income before income taxes 8,050 11,375 3,901 13,775 Provision for income taxes 2,064 3,080 1,512 4,259 Net income $ 5,986 $ 8,295 $ 2,389 $ 9,516 Net income per share: Basic income per share $ 0.05 $ 0.07 $ 0.02 $ 0.08 Diluted income per share $ 0.05 $ 0.07 $ 0.02 $ 0.08 Weighted average shares outstanding: Basic 116,232,528 116,912,332 116,745,476 116,935,708 Diluted 116,535,060 117,635,289 117,044,461 117,545,240 See accompanying notes to condensed consolidated financial statements. 4 Table of Contents ECOVYST INC. AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (in thousands) (unaudited) Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Net income $ 5,986 $ 8,295 $ 2,389 $ 9,516 Other comprehensive income (loss), net of tax: Pension and postretirement benefits 171 530 170 524 Net (loss) gain from hedging activities ( 2,410 ) ( 1,075 ) ( 6,714 ) 2,789 Foreign currency translation 8,582 ( 679 ) 13,113 ( 2,363 ) Total other comprehensive income (loss) 6,343 ( 1,224 ) 6,569 950 Comprehensive income $ 12,329 $ 7,071 $ 8,958 $ 10,466 See accompanying notes to condensed consolidated financial statements. 5 Table of Contents ECOVYST INC. AND SUBSIDIARIES CONDENSED CONSOLIDATED BALANCE SHEETS (in thousands, except share and per share amounts) (unaudited) June 30, 2025 December 31, 2024 ASSETS Cash and cash equivalents $ 69,597 $ 146,013 Accounts receivable, net 103,472 77,937 Inventories, net 66,900 57,126 Derivative assets 4,007 6,532 Prepaid and other current assets 25,437 16,106 Total current assets 269,413 303,714 Investments in affiliated companies 346,495 349,308 Property, plant and equipment, net 602,894 569,275 Goodwill 406,749 404,102 Other intangible assets, net 94,777 98,413 Right-of-use lease assets 37,129 33,558 Other long-term assets 38,941 43,951 Total assets $ 1,796,398 $ 1,802,321 LIABILITIES Current maturities of long-term debt $ 8,730 $ 8,730 Accounts payable 47,936 43,928 Operating lease liabilities—current 8,979 9,267 Accrued liabilities 54,042 53,201 Total current liabilities 119,687 115,126 Long-term debt, excluding current portion 847,884 852,099 Deferred income taxes 104,584 105,395 Operating lease liabilities—noncurrent 28,156 24,189 Other long-term liabilities 3,700 5,052 Total liabilities 1,104,011 1,101,861 Commitments and contingencies (Note 15) EQUITY Common stock ($ 0.01 par); authorized shares 450,000,000 ; issued shares 140,872,846 and 140,872,846 on June 30, 2025 and December 31, 2024, respectively; outstanding shares 114,487,661 and 116,534,803 on June 30, 2025 and December 31, 2024, respectively 1,409 1,409 Preferred stock ($ 0.01 par); authorized shares 50,000,000 ; no shares issued or outstanding on June 30, 2025 and December 31, 2024 — — Additional paid-in capital 1,103,528 1,106,792 Accumulated deficit ( 175,119 ) ( 177,508 ) Treasury stock, at cost; shares 26,385,185 and 24,338,043 on June 30, 2025 and December 31, 2024, respectively ( 236,593 ) ( 222,826 ) Accumulated other comprehensive loss ( 838 ) ( 7,407 ) Total equity 692,387 700,460 Total liabilities and equity $ 1,796,398 $ 1,802,321 See accompanying notes to condensed consolidated financial statements. 6 Table of Contents ECOVYST INC. AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (in thousands) (unaudited) Common stock Additional paid-in capital Accumulated deficit Treasury stock, at cost Accumulated other comprehensive loss Total Balance, December 31, 2024 $ 1,409 $ 1,106,792 $ ( 177,508 ) $ ( 222,826 ) $ ( 7,407 ) $ 700,460 Net loss — — ( 3,597 ) — — ( 3,597 ) Other comprehensive income — — — — 226 226 Tax withholdings on equity award vesting — — — ( 1,477 ) — ( 1,477 ) Stock compensation expense — 3,072 — — — 3,072 Shares issued under equity incentive plan, net of forfeitures — ( 9,519 ) — 9,519 — — Balance, March 31, 2025 $ 1,409 $ 1,100,345 $ ( 181,105 ) $ ( 214,784 ) $ ( 7,181 ) $ 698,684 Net income — — 5,986 — — 5,986 Other comprehensive income — — — — 6,343 6,343 Repurchases of common shares — — — ( 21,917 ) — ( 21,917 ) Excise tax on repurchases of common shares — — — ( 151 ) — ( 151 ) Stock compensation expense — 3,395 — — — 3,395 Shares issued under equity incentive plan, net of forfeitures — ( 212 ) — 259 — 47 Balance, June 30, 2025 $ 1,409 $ 1,103,528 $ ( 175,119 ) $ ( 236,593 ) $ ( 838 ) $ 692,387 Common stock Additional paid-in capital Accumulated deficit Treasury stock, at cost Accumulated other comprehensive (loss) income Total Balance, December 31, 2023 $ 1,407 $ 1,102,581 $ ( 170,856 ) $ ( 226,710 ) $ ( 958 ) $ 705,464 Net income — — 1,221 — — 1,221 Other comprehensive income — — — — 2,174 2,174 Tax withholdings on equity award vesting — — — ( 1,218 ) — ( 1,218 ) Stock compensation expense — 3,674 — — — 3,674 Shares issued under equity incentive plan, net of forfeitures 2 ( 9,290 ) — 9,329 — 41 Balance, March 31, 2024 $ 1,409 $ 1,096,965 $ ( 169,635 ) $ ( 218,599 ) $ 1,216 $ 711,356 Net income — — 8,295 — — 8,295 Other comprehensive income — — — — ( 1,224 ) ( 1,224 ) Repurchases of common shares — — — ( 5,010 ) — ( 5,010 ) Stock compensation expense — 3,827 — — — 3,827 Shares issued under equity incentive plan, net of forfeitures — ( 43 ) — 82 — 39 Balance, June 30, 2024 $ 1,409 $ 1,100,749 $ ( 161,340 ) $ ( 223,527 ) $ ( 8 ) $ 717,283 See accompanying notes to condensed consolidated financial statements. 7 Table of Contents ECOVYST INC. AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (in thousands) (unaudited) Six months ended June 30, 2025 2024 Cash flows from operating activities: Net income $ 2,389 $ 9,516 Adjustments to reconcile net income to net cash provided by operating activities: Depreciation 40,017 36,523 Amortization 7,049 7,034 Amortization of deferred financing costs and original issue discount 701 1,052 Debt extinguishment costs — 90 Foreign currency exchange loss 395 155 Deferred income tax provision (benefit) 1,370 ( 1,690 ) Net loss on asset disposals 417 614 Stock compensation 6,467 7,507 Equity in net (income) from affiliated companies ( 10,844 ) ( 3,464 ) Dividends received from affiliated companies 20,000 33,000 Other, net ( 71 ) 2,216 Working capital changes that provided (used) cash: Receivables ( 14,960 ) ( 4,076 ) Inventories ( 6,029 ) ( 6,693 ) Prepaids and other current assets ( 2,520 ) ( 4,457 ) Accounts payable 6,477 ( 3,289 ) Accrued liabilities ( 7,565 ) ( 27,578 ) Net cash provided by operating activities 43,293 46,460 Cash flows from investing activities: Purchases of property, plant and equipment ( 49,525 ) ( 36,649 ) Business combinations ( 41,315 ) — Other, net — ( 200 ) Net cash used in investing activities ( 90,840 ) ( 36,849 ) Cash flows from financing activities: Issuance of long-term debt, net of original issue discount and financing fees 870,817 870,817 Repayments of long-term debt ( 875,183 ) ( 877,500 ) Repurchases of common shares ( 21,917 ) ( 5,010 ) Tax withholdings on equity award vesting ( 1,477 ) ( 1,218 ) Repayment of financing obligation ( 1,651 ) ( 1,478 ) Other, net 26 41 Net cash used in financing activities ( 29,385 ) ( 14,348 ) Effect of exchange rate changes on cash and cash equivalents 516 ( 310 ) Net change in cash and cash equivalents ( 76,416 ) ( 5,047 ) Cash and cash equivalents at beginning of period 146,013 88,365 Cash and cash equivalents at end of period $ 69,597 $ 83,318 For supplemental cash flow disclosures, see Note 20. See accompanying notes to condensed consolidated financial statements. 8 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) 1. Background and Basis of Presentation: Description of Business Ecovyst Inc. and subsidiaries (the “Company” or “Ecovyst”) is a leading integrated and innovative global provider of advanced materials, specialty catalysts, virgin sulfuric acid and sulfuric acid regeneration services. The Company supports customers globally through its strategically located network of manufacturing facilities. The Company believes that its products and services contribute to improving the sustainability of the environment. The Company has two uniquely positioned specialty businesses: Ecoservices provides sulfuric acid recycling to the North American refining industry for the production of alkylate and provides high quality and high strength virgin sulfuric acid for industrial and mining applications. Ecoservices also provides chemical waste handling and treatment services, as well as ex-situ catalyst activation services for the refining and petrochemical industry. Advanced Materials & Catalysts, through its Advanced Silicas business, provides finished silica catalysts, catalyst supports and functionalized silicas necessary to produce high performing plastics and to enable sustainable chemistry, and through the Zeolyst Joint Venture, innovates and supplies specialty zeolites used in catalysts that support the production of sustainable fuels, remove nitrogen oxides from diesel engine emissions and that are broadly applied in refining and petrochemical processes. The Company’s regeneration services product group, which is a part of the Company’s Ecoservices segment, typically experiences seasonal fluctuations as a result of higher demand for gasoline products in the summer months and lower demand in the winter months. These demand fluctuations result in higher sales and working capital requirements in the second and third quarters. Basis of Presentation The condensed consolidated financial statements included herein are unaudited. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) have been condensed or omitted pursuant to such rules and regulations for interim reporting. In the opinion of management, all adjustments of a normal and recurring nature necessary to state fairly the financial position and results of operations have been included. The results of operations are not necessarily indicative of the expected results for the full year. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024. 2. New Accounting Standards: Accounting Standards Recently Adopted In August 2023, the Financial Accounting Standards Board (“FASB”) issued guidance for entities that meet the definition of a joint venture or a corporate joint venture, to adopt a new basis of accounting upon the formation of the joint venture. The new guidance requires the initial measurement of contributed net assets and liabilities at fair value on the formation date, recognition of goodwill for the difference between the fair value of the joint venture’s equity and net assets, and disclosures about the nature and financial impact of the transaction. The new guidance requires prospective application and is effective for all joint ventures that are formed on or after January 1, 2025, with early adoption permitted. Joint ventures that formed before January 1, 2025 may elect to retrospectively apply the new guidance. The Company has adopted the new guidance as required on January 1, 2025 and will apply the guidance to any new joint ventures formed after the effective date. In November 2023, FASB issued guidance to improve the disclosures related to public business entities (“PBEs”) reportable segments. This new guidance requires entities to provide information regarding significant segment expenses, especially those segment expenses that are regularly reported to the Company’s chief operating decision maker (“CODM,” or the Company’s Chief Executive Officer). The guidance also requires public entities to disclose the nature, type and amounts of other segment items by reportable segment. PBEs will also have to report all annual disclosures about segments profits or losses that are required by ASC 280 on an interim basis, including the significant segment expenses and other segment items. The new guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The Company adopted the new guidance effective December 31, 2024. 9 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) Accounting Standards Not Yet Adopted In November 2024, FASB issued guidance requiring PBEs to disclose additional information on the nature of certain expenses presented in the income statement. The new guidance requires tabular disclosure of significant expense categories and qualitative descriptions for amounts not disaggregated from relevant expense categories. PBEs are required to define selling expenses and disaggregate the components. The new guidance is effective for fiscal years beginning after December 15, 2026 and interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. The requirements must be applied prospectively however PBEs have the option to apply the guidance retrospectively. The disclosure will be implemented as required for the fiscal year ended December 31, 2027. The Company is currently evaluating the impact of this guidance. In December 2023, FASB issued guidance to improve disclosures related to incomes taxes. This new guidance requires PBEs to disaggregate information on the effective tax rate reconciliation and income taxes paid to provide greater transparency. PBEs will be required to provide additional information in specified categories related to effective tax rate reconciliation in tabular form and provide income taxes paid by jurisdictions, with further disaggregation needed if amounts exceed 5% of the total. The new guidance is effective for fiscal years beginning after December 15, 2024. The disclosure will be implemented as required for the fiscal year ended December 31, 2025. The Company is currently evaluating the impact of this guidance. In October 2023, FASB issued guidance to amend either presentation or disclosure requirements related to fourteen subtopics in the FASB Accounting Standards Codification that are currently in the SEC Regulation S-X or Regulation S-K. The new guidance was issued in response to the SEC’s ruling on disclosure simplification. For entities subject to existing SEC disclosure requirements, the effective date of each amendment of the topics will be the date that the SEC removes the related disclosure from Regulation S-X or Regulation S-K. The guidance must be applied prospectively, with no early adoption permitted for entities subject to those existing SEC disclosures. The Company is currently evaluating the impact of the new guidance as it pertains to the fourteen subtopics that would impact the business and will apply prospectively once in effect. 3. Revenue from Contracts with Customers: Disaggregated Revenue The Company’s primary means of disaggregating revenue is by reportable segments, which can be found in Note 17 to these condensed consolidated financial statements. The Company’s portfolio of products is integrated into a variety of end uses, which are described in the table below. Key End Uses Key Products Clean fuels, emission control & other • Refining hydrocracking catalysts • Emission control catalysts • Catalyst supports used in production of sustainable fuels such as renewable diesel • Catalysts used in production of sustainable aviation fuels • Catalyst activation • Aluminum sulfate solution • Ammonium bisulfite solution Polyethylene, polymers & engineered plastics • Catalysts and catalyst supports for high-density polyethylene and chemicals synthesis • Antiblock for film packaging • Catalysts for advanced recycling Regeneration and treatment services • Sulfuric acid regeneration services • Hazardous waste treatment services Industrial, mining & automotive • Virgin sulfuric acid for mining • Virgin sulfuric acid derivatives for industrial production • Virgin sulfuric acid derivatives for nylon production 10 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) The following tables disaggregate the Company’s sales, by segment and end uses, for the three and six months ended June 30, 2025 and 2024, respectively: Three months ended June 30, 2025 Ecoservices Advanced Materials & Catalysts (2) Total Clean fuels, emission control & other $ 8,946 $ — $ 8,946 Polyethylene, polymers & engineered plastics — 24,063 24,063 Regeneration and treatment services (1) 92,788 — 92,788 Industrial, mining & automotive 74,331 — 74,331 Total segment sales $ 176,065 $ 24,063 $ 200,128 Three months ended June 30, 2024 Ecoservices Advanced Materials & Catalysts (2) Total Clean fuels, emission control & other $ 8,614 $ — $ 8,614 Polyethylene, polymers & engineered plastics — 28,862 28,862 Regeneration and treatment services (1) 95,365 — 95,365 Industrial, mining & automotive 49,979 — 49,979 Total segment sales $ 153,958 $ 28,862 $ 182,820 Six months ended June 30, 2025 Ecoservices Advanced Materials & Catalysts (2) Total Clean fuels, emission control & other $ 16,929 $ — $ 16,929 Polyethylene, polymers & engineered plastics — 43,151 43,151 Regeneration and treatment services (1) 172,035 — 172,035 Industrial, mining & automotive 130,211 — 130,211 Total segment sales $ 319,175 $ 43,151 $ 362,326 Six months ended June 30, 2024 Ecoservices Advanced Materials & Catalysts (2) Total Clean fuels, emission control & other $ 16,003 $ — $ 16,003 Polyethylene, polymers & engineered plastics — 47,797 47,797 Regeneration and treatment services (1) 178,684 — 178,684 Industrial, mining & automotive 100,873 — 100,873 Total segment sales $ 295,560 $ 47,797 $ 343,357 (1) As described in Note 1 to these condensed consolidated financial statements, the Company experiences seasonal s ales fluctuations to customers in the regeneration services product group. (2) The Company does not record its proportionate share of sales from the Zeolyst International and Zeolyst C.V. joint ventures (collectively, the “Zeolyst Joint Venture”) accounted for using the equity method as revenue and such sales are not consolidated within its results of operations. See Note 10 to these condensed consolidated financial statements for further information. 11 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) 4. Fair Value Measurements: Fair values are based on quoted market prices when available. When market prices are not available, fair values are generally estimated using discounted cash flow analyses, incorporating current market inputs for similar financial instruments with comparable terms and credit quality. In instances where there is little or no market activity for the same or similar instruments, the Company estimates fair values using methods, models and assumptions that management believes a hypothetical market participant would use to determine a current transaction price. These valuation techniques involve some level of management estimation and judgment that becomes significant with increasingly complex instruments or pricing models. Where appropriate, adjustments are included to reflect the risk inherent in a particular methodology, model or input used. The Company’s financial assets and liabilities carried at fair value have been classified based upon a fair value hierarchy. The hierarchy gives the highest ranking to fair values determined using unadjusted quoted prices in active markets for identical assets and liabilities (Level 1) and the lowest ranking to fair values determined using methodologies and models with unobservable inputs (Level 3). The classification of an asset or a liability is based on the lowest level input that is significant to its measurement. For example, a Level 3 fair value measurement may include inputs that are both observable (Levels 1 and 2) and unobservable (Level 3). The levels of the fair value hierarchy are as follows: • Level 1—Values are unadjusted quoted prices for identical assets and liabilities in active markets accessible at the measurement date. Active markets provide pricing data for trades occurring at least weekly and include exchanges and dealer markets. • Level 2—Inputs include quoted prices for similar assets or liabilities in active markets, quoted prices from those willing to trade in markets that are not active, or other inputs that are observable or can be corroborated by market data for the term of the instrument. Such inputs include market interest rates and volatilities, spreads and yield curves. • Level 3—Certain inputs are unobservable (supported by little or no market activity) and significant to the fair value measurement. Unobservable inputs reflect the Company’s best estimate of what hypothetical market participants would use to determine a transaction price for the asset or liability at the reporting date. Fair value on a recurring basis The following tables present information about the Company’s assets and liabilities that were measured at fair value on a recurring basis as of June 30, 2025 and December 31, 2024, and indicates the fair value hierarchy of the valuation techniques the Company utilized to determine such fair value. June 30, 2025 Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Derivative assets: Interest rate caps (Note 12) $ 4,296 $ — $ 4,296 $ — Derivative liabilities: Interest rate caps (Note 12) $ 1,628 $ — $ 1,628 $ — December 31, 2024 Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Derivative assets: Interest rate caps (Note 12) $ 12,500 $ — $ 12,500 $ — Derivative liabilities: Interest rate caps (Note 12) $ 710 $ — $ 710 $ — 12 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) Derivative contracts Derivative assets and liabilities can be exchange-traded or traded over-the-counter (“OTC”). The Company generally values exchange-traded derivatives using models that calibrate to market transactions and eliminate timing differences between the closing price of the exchange-traded derivatives and their underlying instruments. OTC derivatives are valued using market transactions and other market evidence whenever possible, including market-based inputs to models, model calibration to market transactions, broker or dealer quotations or alternative pricing sources with reasonable levels of price transparency. When models are used, the selection of a particular model to value an OTC derivative depends on the contractual terms of, and specific risks inherent in, the instrument as well as the availability of pricing information in the market. The Company generally uses similar models to value similar instruments. Valuation models require a variety of inputs, including contractual terms, market prices and rates, forward curves, measures of volatility, and correlations of such inputs. For OTC derivatives that trade in liquid markets, such as forward contracts, swaps and options, model inputs can generally be corroborated by observable market data by correlation or other means, and model selection does not involve significant management judgment. As of June 30, 2025, th e Company had interest rate c aps th at were fair valued using Level 2 inputs. In addition, the Company applies a credit valuation adjustment to reflect credit risk which is calculated based on credit default swaps. To the extent that the Company’s net exposure under a specific master agreement is an asset, the Company utilizes the counterparty’s default swap rate. If the net exposure under a specific master agreement is a liability, the Company utilizes a default swap rate comparable to Ecovyst. The credit valuation adjustment is added to the discounted fair value to reflect the exit price that a market participant would be willing to receive to assume the Company’s liabilities or that a market participant would be willing to pay for the Company’s assets. Fair value on a non-recurring basis Non-marketable equity securities The Company’s non-marketable equity securities consist of an investment in a privately-held company without readily determinable market values. Non-marketable equity securities are accounted for using the measurement alternative, defined as cost less impairment, if any, plus or minus adjustments from observable price changes for identical or similar securities of the same issuer. Adjustments to fair value or impairments, if any, are recorded in the condensed consolidated statements of income. In July 2024, the Company paid $ 4,500 for a minority equity investment in Pajarito Powder LLC (“Pajarito”), an innovative materials science company that focuses on supports and catalysts required for the manufacture and operation of electrolyzers and fuel cells. The investment is recorded in other long-term assets in the condensed consolidated balance sheet. As of June 30, 2025, the carrying value in Pajarito was $ 4,500 . There were no remeasurement events or recognized gains or losses for the three and six months ended June 30, 2025. 13 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) 5. Stockholders' Equity: Accumulated Other Comprehensive Loss The following tables present the tax effects of each component of other comprehensive income (loss) for the three and six months ended June 30, 2025 and 2024, respectively: Three months ended June 30, 2025 2024 Pre-tax amount Tax benefit/(expense) After-tax amount Pre-tax amount Tax benefit/(expense) After-tax amount Defined benefit and other postretirement plans: Net gain $ 226 $ ( 55 ) $ 171 $ 714 $ ( 178 ) $ 536 Net prior service cost — — — ( 7 ) 1 ( 6 ) Benefit plans, net 226 ( 55 ) 171 707 ( 177 ) 530 Net loss from hedging activities ( 3,214 ) 804 ( 2,410 ) ( 1,433 ) 358 ( 1,075 ) Foreign currency translation 8,582 — 8,582 ( 679 ) — ( 679 ) Other comprehensive income (loss) $ 5,594 $ 749 $ 6,343 $ ( 1,405 ) $ 181 $ ( 1,224 ) Six months ended June 30, 2025 2024 Pre-tax amount Tax benefit/ (expense) After-tax amount Pre-tax amount Tax benefit/ (expense) After-tax amount Defined benefit and other postretirement plans: Net gain $ 225 $ ( 55 ) $ 170 $ 713 $ ( 178 ) $ 535 Net prior service cost — — — ( 15 ) 4 ( 11 ) Benefit plans, net 225 ( 55 ) 170 698 ( 174 ) 524 Net (loss) gain from hedging activities ( 8,952 ) 2,238 ( 6,714 ) 3,719 ( 930 ) 2,789 Foreign currency translation 13,113 — 13,113 ( 2,363 ) — ( 2,363 ) Other comprehensive income $ 4,386 $ 2,183 $ 6,569 $ 2,054 $ ( 1,104 ) $ 950 The following tables present the changes in accumulated other comprehensive income (loss) (“AOCI”), net of tax, by component for the six months ended June 30, 2025 and 2024, respectively: Defined benefit and other postretirement plans Net gain (loss) from hedging activities Foreign currency translation Total December 31, 2024 $ 1,467 $ 9,902 $ ( 18,776 ) $ ( 7,407 ) Other comprehensive income (loss) before reclassifications 172 ( 3,545 ) 13,113 9,740 Amounts reclassified from AOCI (1) ( 2 ) ( 3,169 ) — ( 3,171 ) Net current period other comprehensive income (loss) 170 ( 6,714 ) 13,113 6,569 June 30, 2025 $ 1,637 $ 3,188 $ ( 5,663 ) $ ( 838 ) December 31, 2023 $ 612 $ 12,546 $ ( 14,116 ) $ ( 958 ) Other comprehensive income (loss) before reclassifications 540 9,778 ( 2,363 ) 7,955 Amounts reclassified from AOCI (1) ( 16 ) ( 6,989 ) — ( 7,005 ) Net current period other comprehensive income (loss) 524 2,789 ( 2,363 ) 950 June 30, 2024 $ 1,136 $ 15,335 $ ( 16,479 ) $ ( 8 ) (1) See the following table for details about these reclassifications. Amounts in parentheses indicate debits. 14 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) The following table presents the reclassifications out of AOCI for the three and six months ended June 30, 2025 and 2024, respectively: Details about AOCI Components Amounts reclassified from AOCI (1) Affected line item where income is presented Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Amortization of defined benefit and other postretirement items: Net loss $ 2 $ 6 $ 3 $ 7 Other expense (2) Net prior service cost — 7 — 15 Other expense (2) 2 13 3 22 Total before tax ( 1 ) ( 3 ) ( 1 ) ( 6 ) Tax benefit $ 1 $ 10 $ 2 $ 16 Net of tax Gains and losses on cash flow hedges: Interest rate caps $ 2,085 $ 4,662 $ 4,225 $ 9,318 Interest expense ( 521 ) ( 1,166 ) ( 1,056 ) ( 2,329 ) Tax benefit $ 1,564 $ 3,496 $ 3,169 $ 6,989 Net of tax Total reclassifications for the period $ 1,565 $ 3,506 $ 3,171 $ 7,005 Net of tax (1) Amounts in parentheses indicate debits to profit/loss. (2) These AOCI components are components of net periodic pension and other postretirement cost (see Note 14 to these condensed consolidated financial statements for additional details). Treasury Stock Repurchases 2022 Stock Repurchase Program On April 27, 2022, the Board approved a stock repurchase program that authorized the Company to purchase up to $ 450,000 of the Company’s common stock over the four-year period from the date of approval. Under the plan, the Company is permitted to repurchase shares from time to time for cash in open market transactions or in privately negotiated transactions in accordance with applicable federal securities laws, with the Company determining the timing and the amount of any repurchases based on its evaluation of market conditions, share price and other factors. During the six months ended June 30, 2025, the Company repurchased 2,926,152 shares on the open market at an average price of $ 7.47 per share, for a total of $ 21,859 , excluding brokerage commissions and accrued excise tax. During the six months ended June 30, 2025, the Company accrued $ 151 of excise tax related to these repurchases, net of shares issued under the Company’s equity incentive program (see Note 18 to these condensed consolidated financial statements). As of June 30, 2025, $ 207,735 was available for share repurchases under the program. During the six months ended June 30, 2024, the Company repurchased 552,081 shares on the open market at an average price of $ 9.05 per share, for a total of $ 4,998 , excluding brokerage commissions and accrued excise tax. During the six months ended June 30, 2024, the Company did not need to accrue excise tax related to these repurchases, net of shares issued under the Company’s equity incentive program (see Note 18 to these condensed consolidated financial statements). 15 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) Tax Withholdings on Equity Award Vesting In connection with the vesting of restricted stock awards (“RSA” or “RSAs”), restricted stock units (“RSU” or “RSUs”) and performance stock units (“PSU” or “PSUs”), shares of common stock may be delivered to the Company by employees to satisfy withholding tax obligations at the instruction of the employee award holders. These transactions, when they occur, are accounted for as stock repurchases by the Company, with the shares returned to treasury stock at a cost representing the payment by the Company of the tax obligations on behalf of the employees in lieu of shares for the vesting event. There were 189,446 and 128,801 shares delivered to the Company to cover tax payments for the six months ended June 30, 2025 and 2024, respectively, and the fair value of those shares withheld were $ 1,477 and $ 1,218 for the six months ended June 30, 2025 and 2024, respectively. 6. Goodwill: The change in the carrying amount of goodwill for the six months ended June 30, 2025 is summarized as follows: Ecoservices Advanced Materials & Catalysts Total Balance as of December 31, 2024 $ 326,589 $ 77,513 $ 404,102 Goodwill recognized (Note 7) 363 — 363 Foreign exchange impact — 2,284 2,284 Balance as of June 30, 2025 $ 326,952 $ 79,797 $ 406,749 The Company completes its annual goodwill and indefinite-lived intangible assets impairment test during the fourth quarter of each year, or more frequently if triggering events indicate a possible impairment. The Company determined the fair value of its reporting units using both a market approach and an income, or discounted cash flow, approach. As of October 1, 2024, the date of the Company’s most recent quantitative assessments, the fair values of each of the Company’s reporting units and the fair values of the Company’s indefinite-lived trade names and trademarks exceeded their respective carrying values. During the six months ended June 30, 2025, the Company did not identify any events or circumstances that would more likely than not reduce the fair value of the Company's reporting units below their respective carrying values. The estimated fair value of the Advanced Materials & Catalysts reporting unit exceeded its carrying value on October 1, 2024 by over 15 %. Prolonged unfavorable effects or results of the current strategic review could adversely impact the estimated fair value of the Advanced Materials & Catalysts reporting unit in future periods and may result in impairment charges. 16 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) 7. Acquisition: On May 6, 2025 (the “Closing Date”), the Company completed its acquisition of the sulfuric acid production assets of Cornerstone Chemical Company LLC (“Cornerstone”) located in Waggaman, Louisiana. As part of an asset purchase agreement (the “Acquisition”), the Company paid $ 41,315 in cash, consisting of the $ 35,000 purchase price plus $ 6,315 of adjustments for working capital, pursuant to the agreement. The sulfuric acid production assets will be used to increase capacity of virgin sulfuric acid and sulfuric acid regeneration services to current and future customers. The Acquisition is a business combination, therefore the acquisition method was applied. Under the acquisition method, the purchase price was allocated to the identifiable assets acquired based on the fair values of the identifiable assets acquired as of the Closing Date. The excess of the purchase price over fair values of the identifiable assets acquired was recorded to goodwill. The table below presents the provisional fair values allocated to the assets acquired. The purchase accounting and purchase price allocation for Cornerstone are preliminary and the Company continues to refine the preliminary valuation of certain acquired assets which could impact the amount of residual goodwill recorded. The Company intends to finalize the amounts recognized as it obtains the information necessary to complete the analysis, but no later than one year from the date of the acquisition. Final determination of the fair values may result in further adjustments to the values presented in the following table: Preliminary Purchase Price Allocation Cash paid $ 41,315 Recognized amounts of identifiable assets acquired: Accounts receivable $ 9,812 Inventories 3,055 Property, plant and equipment 25,000 Other intangible assets 2,390 Other long-term assets 695 Fair value of identifiable assets acquired 40,952 Goodwill 363 Total assets acquired $ 41,315 Adjustments to the preliminary amounts during the measurement period that result in changes to depreciation, amortization or other income effects will be recognized in the reporting period(s) in which the adjustments are determined. In accordance with the requirements of the purchase method of accounting for acquisitions, accounts receivable and inventories were recorded at fair market value. As of the Closing Date, the fair value of accounts receivable approximated historical cost. The gross contractual amount of accounts receivable at the Closing Date was $ 9,812 , of which there was no amount deemed uncollectible. Fair value of inventory is defined as estimated selling prices less the sum of (a) costs of disposal and (b) a reasonable profit allowance for the selling effort of the acquiring entity. Prior to the acquisition, the Company had a preexisting relationship with Cornerstone. The Company had a net payable of $ 619 for a sulfuric acid exchange balance. As part of the acquisition terms, the payable was settled at cost, which was recorded separate from the business combination. 17 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) The valuation of intangibles assets acquired and the related weighted-average amortization period are as follows: Amount Weighted-Average Expected Useful Life (in years) Intangible assets subject to amortization: Customer relationships $ 2,390 15 Net sales and net income attributable to Cornerstone during the period from the Closing Date through June 30, 2025 were immaterial. Pro forma financial information has not been presented as it is immaterial for the three and six months ended June 30, 2025. Acquisition and integration costs were $ 806 and $ 2,755 for the three and six months ended June 30, 2025, respectively, and are included in other operating expense, net in the Company’s condensed consolidated statements of income. The Company entered into an agreement with Cornerstone to lease the land where the acquired assets are located for a 7 year term plus renewal options. Additionally, Cornerstone will charge the Company for site services and utilities for the location. 8. Other Operating Expense, Net: A summary of other operating expense, net is as follows: Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Amortization expense $ 2,655 $ 2,644 $ 5,298 $ 5,289 Transaction and other related costs 2,661 140 4,528 198 Restructuring, integration and business optimization costs 1,030 159 1,167 385 Net loss (gain) on asset disposals 250 ( 34 ) 417 614 Other, net 2,656 199 3,023 288 Total other operating expense, net $ 9,252 $ 3,108 $ 14,433 $ 6,774 9. Inventories, Net: Inventories, net are classified and valued as follows: June 30, 2025 December 31, 2024 Finished products and work in process $ 60,466 $ 54,124 Raw materials 6,434 3,002 Total inventories, net $ 66,900 $ 57,126 Valued at lower of cost or market: LIFO basis $ 38,702 $ 31,650 Valued at lower of cost and net realizable value: FIFO or average cost basis 28,198 25,476 Total inventories, net $ 66,900 $ 57,126 18 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) 10. Investments in Affiliated Companies: The Company accounts for investments in affiliated companies under the equity method. Affiliated companies accounted for on the equity basis as of June 30, 2025 are as follows: Company Country Percent ownership Zeolyst International USA 50 % Zeolyst C.V. Netherlands 50 % Following is summarized information of the combined investments (1) : Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Sales $ 68,579 $ 70,644 $ 158,109 $ 127,505 Gross profit 13,522 16,751 41,952 33,929 Operating income 4,044 5,739 22,250 12,583 Net income 5,076 4,665 23,727 12,010 (1) Summarized information of the combined investments is presented at 100%; the Company’s share of the net assets and net income of affiliates is calculated based on the percent ownership specified in the table above. The Company’s investments in affiliated companies balance as of June 30, 2025 and December 31, 2024 includes net purchase accounting fair value adjustments of $ 153,918 and $ 155,138 , respectively, related to a prior business combination consisting primarily of goodwill and intangible assets such as technical know-how and trade names. Consolidated equity in net income from affiliates is net of $ 610 and $ 1,220 of amortization expense related to purchase accounting fair value adjustments for the three and six months ended June 30, 2025, respectively. Consolidated equity in net income from affiliates is net of $ 940 and $ 2,541 of amortization expense related to purchase accounting fair value adjustments for the three and six months ended June 30, 2024, respectively. The Company had receivables due from affiliates of $ 2,770 and $ 2,794 as of June 30, 2025 and December 31, 2024, respectively, which were included in prepaid and other current assets in the condensed consolidated balance sheets. The Company had payables to affiliates of $ 2,281 and $ 929 as of June 30, 2025 and December 31, 2024, respectively, which were included in accrued liabilities in the condensed consolidated balance sheets. Receivables and payables due from/to affiliates are generally non-trade. The Company had $ 1,579 and $ 2,461 of sales to affiliates for the three and six months ended June 30, 2025, respectively and $ 2,110 of sales to affiliates for the three and six months ended June 30, 2024. There were no purchases from affiliates for the three and six months ended June 30, 2025 and 2024. 19 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) 11. Long-term Debt: The summary of long-term debt is as follows: June 30, 2025 December 31, 2024 2025 Term Loan Facility $ 866,453 $ 870,817 ABL Facility — — Total debt 866,453 870,817 Original issue discount ( 6,725 ) ( 7,201 ) Deferred financing costs ( 3,114 ) ( 2,787 ) Total debt, net of original issue discount and deferred financing costs 856,614 860,829 Less: current portion ( 8,730 ) ( 8,730 ) Total long-term debt, excluding current portion $ 847,884 $ 852,099 Term Loan Facility In June 2024, the Company amended its Term Loan Credit Agreement dated as of June 9, 2021 to, among other things, (a) reduce the interest rate applicable to all outstanding Secured Overnight Financing Rate (“SOFR”) term loans to a rate equal to the forward-looking term rate based on SOFR as administered by the Federal Reserve Bank of New York (“Term SOFR”) plus 2.25 % per annum from a maximum of adjusted Term SOFR plus 2.75 % per annum, (b) reduce the interest rate applicable to all outstanding base rate term loans to the alternate base rate plus 1.25 % per annum from a maximum of the alternate base rate plus 1.75 % per annum and (c) extend the maturity date of all outstanding term loans to June 12, 2031. As a result of the amendment, there is no longer a credit spread adjustment of 10 basis points. In January 2025, the Company amended its Term Loan Credit Agreement dated as of June 12, 2024 to, among other things, (a) reduce the interest rate applicable to all outstanding SOFR term loans to Term SOFR plus 2.00 % per annum from a maximum of Term SOFR plus 2.25 % per annum and (b) reduce the interest rate applicable to all outstanding base rate term loans to the alternate base rate plus 1.00 % per annum from a maximum of the alternate base rate plus 1.25 % per annum (the amended term loans, the “2025 Term Loan Facility”). The Company evaluated the terms of the amendments in accordance with ASC 470-50 Debt - Modification and Extinguishment and determined that both amendments were a modification of debt. As a result of the January 2025 amendment, the Company recorded $ 960 of third-party financing costs within debt modification and extinguishment costs in the condensed consolidated statements of income for the six months ended June 30, 2025. No third-party financing costs were recorded for the three months ended June 30, 2025, and no original issue discount was paid for the three and six months ended June 30, 2025. As a result of the June 2024 amendment, the Company recorded $ 4,471 of third-party financing costs within debt modification and extinguishment costs in the condensed consolidated statements of income for the three and six months ended June 30, 2024 and capitalized $ 2,183 of original issued discount within long-term debt, excluding current portion in the condensed consolidated balance sheets during the quarter ended June 30, 2024. In addition, $ 89 of previous unamortized deferred financing costs and original issue discount associated with the previously outstanding debt were written off as debt modification and extinguishment costs for the three and six months ended June 30, 2024. The interest rate on the 2025 Term Loan Facility was 6.29 % as of June 30, 2025. ABL Facility The borrowings under the senior secured asset-based lending revolving credit facility (“ABL Facility”) bear interest at a rate equal to an adjusted Term SOFR or the base rate plus a margin of between 1.25 % to 1.75 % or 0.25 % to 0.75 %, respectively. The interest rate on the ABL Facility was 7.75 % as of June 30, 2025. In April 2025, the Company amended its ABL credit agreement (“ABL Credit Agreement”) to, among other things, (a) reallocate all European revolving loan commitments thereunder as United States revolving loan commitments, (b) extend the maturity date with respect to borrowings under the ABL Credit Agreement by over three years to April 10, 2030 (subject to acceleration under certain circumstances), (c) reduce the interest rate applicable to outstanding revolving loans that bear interest at a rate equal to Term SOFR by removing the credit spread adjustment that was applied to Term SOFR in the ABL Credit Agreement in calculating adjusted Term SOFR, and (d) reduce the frequency of borrowing base reporting, field examinations and appraisals (subject to higher frequency under certain circumstances). As a result of the amendment, the Company capitalized $ 551 of deferred financing costs within long-term debt, excluding current portion in the condensed consolidated balance sheets during the quarter ended June 30, 2025. 20 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) Fair Value of Debt The fair value of a financial instrument is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants. As of June 30, 2025 and December 31, 2024, the fair value of the Company’s term loan facility was $ 859,954 and $ 874,083 , respectively. The fair value is classified as Level 2 based upon the fair value hierarchy (see Note 4 to these condensed consolidated financial statements for further information on fair value measurements). 12. Financial Instruments: The Company uses interest rate related derivative instruments to manage its exposure to changes in interest rates on its variable-rate debt instruments. The Company does not speculate using derivative instruments. By using derivative financial instruments to hedge exposures to changes in interest rates, the Company exposes itself to credit risk and market risk. Credit risk is the failure of the counterparty to perform under the terms of the derivative contract. When the fair value of a derivative contract is an asset, the counterparty owes the Company, which creates credit risk for the Company. When the fair value of a derivative contract is a liability, the Company owes the counterparty and therefore, the Company is not exposed to the counterparty’s credit risk in those circumstances. The Company minimizes counterparty credit risk in derivative instruments by entering into transactions with high quality counterparties. The derivative instruments entered into by the Company do not contain credit-risk-related contingent features. Market risk is the adverse effect on the value of a derivative instrument that results from a change in interest rates. The market risk associated with the Company’s derivative instruments is managed by establishing and monitoring parameters that limit the types and degree of market risk that may be undertaken. Use of Derivative Financial Instruments to Manage Interest Rate Risk The Company is exposed to fluctuations in interest rates on its senior secured credit facilities. Changes in interest rates will not affect the market value of such debt but will affect the Company’s interest payments over the term of the loans. Likewise, an increase in interest rates could have a material impact on the Company’s condensed consolidated statements of cash flows. The Company hedges the interest rate fluctuations on debt obligations through interest rate cap agreements. The Company records these agreements at fair value as assets or liabilities in the condensed consolidated balance sheets. As the derivatives are designated and qualify as cash flow hedges, the gains or losses on the interest rate cap agreements are recorded in stockholders’ equity as a component of other comprehensive income, net of tax. Reclassifications of the gains and losses on the interest rate cap agreements into earnings are recorded as part of interest expense in the condensed consolidated statements of income as the Company makes its interest payments on the hedged portion of its senior secured credit facilities. Fair value is determined based on estimated amounts that would be received or paid to terminate the contracts at the reporting date based on quoted market prices. The following table provides a summary of the Company’s interest rate cap agreements: Financial instrument Number of instruments In effect as of June 30, 2025 Current notional amount of instruments in effect Annuitized premium of instruments in effect Cap rate in effect for all agreements at June 30, 2025 Interest rate caps 4 3 $ 625,000 $ 35,285 1.00 % The current notional amounts of the three interest rate cap agreements in effect at June 30, 2025 are $ 250,000 , $ 175,000 and $ 200,000 . The Company entered into a $ 250,000 interest rate cap to mitigate interest rate volatility from September 2023 to October 2025, a $ 175,000 interest rate cap agreement to mitigate interest rate volatility from August 2024 to July 2026 and a $ 200,000 interest rate cap agreement to mitigate interest rate volatility from November 2024 to October 2025. The $ 200,000 interest rate cap agreement will increase to $ 450,000 to mitigate interest rate volatility from November 2025 to October 2026. The Company also entered into a $ 200,000 forward starting interest rate cap agreement to mitigate interest volatility from August 2026 to July 2028. 21 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) The fair values of derivative instruments held as of June 30, 2025 and December 31, 2024, respectively, are shown below: Balance sheet location June 30, 2025 December 31, 2024 Derivative assets Derivatives designated as cash flow hedges: Interest rate caps Prepaid and other current assets $ 4,007 $ 6,532 Interest rate caps Other long-term assets 289 5,968 Total derivative assets $ 4,296 $ 12,500 Derivative liabilities Derivatives designated as cash flow hedges: Interest rate caps Accrued liabilities $ 619 $ 235 Interest rate caps Other long-term liabilities 1,009 475 Total derivative liabilities $ 1,628 $ 710 The following tables show the effect of the Company’s derivative instruments designated as cash flow hedges on AOCI and the condensed consolidated statements of income for the three and six months ended June 30, 2025 and 2024, respectively: Amount of (loss) gain recognized in OCI Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Interest rate caps $ ( 1,129 ) $ 3,229 $ ( 4,727 ) $ 13,037 Amount of (loss) gain reclassified from AOCI Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Interest rate caps $ ( 2,085 ) $ ( 4,662 ) $ ( 4,225 ) $ ( 9,318 ) Amount of loss reclassified into income Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Interest rate caps $ 2,085 $ 4,662 $ 4,225 $ 9,318 22 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) The following table shows the amounts in the line items presented in the condensed consolidated statements of income in which the effects of derivatives designated as cash flow hedges are recorded for the three and six months ended June 30, 2025 and 2024, respectively: Three months ended June 30, Location and amount of gain (loss) recognized in income on cash flow hedging relationships 2025 2024 Interest rate caps Interest expense $ ( 11,117 ) $ ( 12,895 ) Six months ended June 30, 2025 2024 Interest rate caps Interest expense $ ( 22,127 ) $ ( 26,304 ) The amount of net unrealized gains in AOCI related to the Company’s cash flow hedges that is expected to be reclassified to the condensed consolidated statements of income over the next twelve months is $ 4,137 as of June 30, 2025. 13. Income Taxes: The effective income tax rate for the three months ended June 30, 2025 was 25.6 %, compared to 27.1 % for the three months ended June 30, 2024. The effective income tax rate for the six months ended June 30, 2025 was 38.8 %, compared to 30.9 % for the six months ended June 30, 2024. The Company’s effective income tax rates for the three and six months ended June 30, 2025 and 2024, respectively, fluctuated primarily due to the increased discrete tax impact relative to pre-tax book income related to a stock compensation shortfall, state tax law changes, state tax refunds associated with prior tax years and expense related to accrued penalties and interest on historical uncertain tax positions. The difference between the U.S. federal statutory income tax rate and the Company’s effective income tax rate for the six months ended June 30, 2025 was mainly due to state and local taxes, a shortfall tax expense related to stock compensation, state and local tax law changes and a tax benefit related to state tax refunds associated with prior tax years. The difference between the U.S. federal statutory income tax rate and the Company’s effective income tax rate for the six months ended June 30, 2024 was mainly due to state and local taxes, a discrete shortfall tax expense related to stock compensation and a discrete tax expense associated with the recording of accrued penalties and interest on historical uncertain tax positions. On July 4, 2025, H.R.1, the One Big Beautiful Bill Act (“OBBBA”), was enacted in the U.S. The OBBBA includes significant provisions, such as the permanent extension of certain expiring provisions of the Tax Cuts and Jobs Act, modifications to the international tax framework and the restoration of favorable tax treatment for certain business provisions. The legislation has multiple effective dates, with certain provisions effective in 2025 and others implemented through 2027. We are currently assessing its impact on our condensed consolidated financial statements. 14. Benefit Plans: The following tables present the components of net periodic expense (benefit) for the Company-sponsored defined benefit pension and postretirement plans, which cover certain employees and retirees located in the U.S.: Defined Benefit Pension Plans Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Interest cost $ 820 $ 808 $ 1,642 $ 1,616 Expected return on plan assets ( 808 ) ( 827 ) ( 1,617 ) ( 1,654 ) Settlement gain ( 1 ) ( 6 ) ( 1 ) ( 6 ) Net periodic expense (benefit) $ 11 $ ( 25 ) $ 24 $ ( 44 ) 23 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) Other Postretirement Benefit Plan Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Interest cost $ 7 $ 6 $ 13 $ 12 Amortization of prior service credit — ( 7 ) — ( 15 ) Amortization of net gain ( 1 ) — ( 2 ) ( 1 ) Net periodic expense (benefit) $ 6 $ ( 1 ) $ 11 $ ( 4 ) All components of net periodic expense (benefit) are presented within other expense, net in the Company’s condensed consolidated statements of income. 15. Commitments and Contingent Liabilities: There is a risk of environmental impact in the Company’s manufacturing operations. The Company’s environmental policies and practices are designed to comply with existing laws and regulations and to minimize the possibility of significant environmental impact. The Company is also subject to various other lawsuits and claims with respect to matters such as governmental regulations, labor and other actions arising out of the normal course of business. All claims that are probable and reasonably estimable have been accrued for in the Company’s condensed consolidated financial statements. When these matters are ultimately concluded and determined, the Company believes that there will be no material adverse effect on its condensed consolidated financial position, results of operations or liquidity. 16. Related Party Transactions: The Company maintains certain policies and procedures for the review, approval and ratification of related party transactions to ensure that all transactions with selected parties are fair, reasonable and in the Company’s best interests. All significant relationships and transactions are separately identified by management if they meet the definition of a related party or a related party transaction. Related party transactions include transactions that occurred during the year, or are currently proposed, in which the Company was or will be a participant, and for which any related person had or will have a direct or indirect material interest. All related party transactions are reviewed, approved and documented by the appropriate level of the Company’s management in accordance with these policies and procedures. Joint Venture Agreement The Company entered into a joint venture agreement (the “ZI Partnership Agreement”) in 1988 with Shell Catalysts & Technologies, an affiliate of Royal Dutch Shell plc, to form Zeolyst International, a 50/50 joint venture partnership (the “Partnership”). Under the terms of the ZI Partnership Agreement, the Partnership leases certain land used in its Kansas City production facilities from Ecovyst. This lease, which has been recorded as an operating lease and with evergreen terms as long as the ZI Partnership Agreement is in place, provided for rental payments to the Company of $ 78 and $ 155 for the three and six months ended June 30, 2025 and 2024, respectively. These rental payments were included in cost of goods sold in the condensed consolidated statements of income. The Partnership had no sales to the Company for the three and six months ended June 30, 2025 and 2024. The Partnership purchases certain raw materials from the Company and was charged for various manufacturing costs incurred at the Company’s Kansas City production facility. The amount of these costs charged to the Partnership were $ 5,142 and $ 9,758 for the three and six months ended June 30, 2025, respectively and $ 6,050 and $ 10,084 for the three and six months ended June 30, 2024, respectively, which were included in cost of goods sold in the condensed consolidated statements of income. In addition, the Partnership was charged certain product demonstration costs of $ 259 and $ 485 for the three and six months ended June 30, 2025, respectively and $ 238 and $ 595 for the three and six months ended June 30, 2024, respectively, which were also included in cost of goods sold in the condensed consolidated statements of income. Certain administrative, marketing, engineering, management-related and research and development services are provided to the Partnership by the Company. The Partnership was charged $ 4,121 and $ 8,243 for the three and six months ended June 30, 2025 and $ 4,600 and $ 8,900 for the three and six months ended June 30, 2024, respectively, which were included in selling, general and administrative expenses in the condensed consolidated statements of income. 24 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) The Company had an accounts receivable from the Partnership of $ 2,770 and $ 2,794 as of June 30, 2025 and December 31, 2024, respectively, which were included in prepaid and other current assets in the condensed consolidated balance sheet. Accounts payable to the Partnership was immaterial as of June 30, 2025. There were no accounts payable with the Partnership as of December 31, 2024. 17. Reportable Segments: Summarized financial information for the Company’s reportable segments is shown in the following table: Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Sales: Ecoservices $ 176,065 $ 153,958 $ 319,175 $ 295,560 Advanced Materials & Catalysts (1) 24,063 28,862 43,151 47,797 Total $ 200,128 $ 182,820 $ 362,326 $ 343,357 Adjusted EBITDA: (2) Ecoservices $ 49,772 $ 49,709 $ 78,296 $ 91,203 Advanced Materials & Catalysts (3) 13,717 14,717 31,221 25,846 Adjusted EBITDA from reportable segments $ 63,489 $ 64,426 $ 109,517 $ 117,049 (1) The Company does not record its proportionate share of sales from the Zeolyst Joint Venture accounted for using the equity method as revenue and such sales are not consolidated within its results of operations. See Note 10 to these condensed consolidated financial statements for further information. The Company’s proportionate share of sales from the Zeolyst Joint Venture was $ 28,444 and $ 66,186 for the three and six months ended June 30, 2025, respectively. The Company’s proportionate share of sales from the Zeolyst Joint Venture was $ 29,024 and $ 52,505 for the three and six months ended June 30, 2024, respectively. (2) The Company defines Adjusted EBITDA as EBITDA adjusted for certain items as noted in the reconciliation below. Management evaluates the performance of its segments and allocates resources based on several factors, of which the primary measure is Adjusted EBITDA. Adjusted EBITDA should not be considered as an alternative to net income as an indicator of the Company’s operating performance. Adjusted EBITDA as defined by the Company may not be comparable with EBITDA or Adjusted EBITDA as defined by other companies. (3) The Adjusted EBITDA for the Company’s Advanced Materials & Catalysts segment reflects the Company’s 50 % portion of the earnings from the Zeolyst Joint Venture that have been recorded as equity in net income in its condensed consolidated statements of income and includes Zeolyst Joint Venture adjustments on a proportionate basis based on the Company’s 50 % ownership interest. For the three months ended June 30, 2025, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $ 5,722 , which includes $ 1,928 of equity in net income plus $ 610 of amortization of investment in affiliate step-up and $ 3,184 of joint venture depreciation, amortization and interest. For the six months ended June 30, 2025, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $ 18,403 , which includes $ 10,844 of equity in net income plus $ 1,220 of amortization of investment in affiliate step-up and $ 6,339 of joint venture depreciation, amortization and interest. For the three months ended June 30, 2024, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $ 5,559 , which includes $ 1,392 of equity in net income plus $ 940 of amortization of investment in affiliate step-up and $ 3,227 of joint venture depreciation, amortization and interest. For the six months ended June 30, 2024, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $ 12,486 , which includes $ 3,464 of equity in net income plus $ 2,541 of amortization of investment in affiliate step-up and $ 6,481 of joint venture depreciation, amortization and interest. 25 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) The following tables reconcile sales to Adjusted EBITDA from reportable segments: Three months ended June 30, 2025 Ecoservices Advanced Materials & Catalysts Total Sales (1) $ 176,065 $ 24,063 $ 200,128 Less: (2) Cost of goods sold 119,313 11,822 Selling, general and administrative expenses 6,776 3,934 Other segment items (3) 204 312 Add: Adjusted EBITDA from the Zeolyst Joint Venture — 5,722 Adjusted EBITDA from reportable segments $ 49,772 $ 13,717 $ 63,489 Three months ended June 30, 2024 Ecoservices Advanced Materials & Catalysts Total Sales (1) $ 153,958 $ 28,862 $ 182,820 Less: (2) Cost of goods sold 97,404 15,843 Selling, general and administrative expenses 6,861 3,764 Other segment items (3) ( 16 ) 97 Add: Adjusted EBITDA from the Zeolyst Joint Venture — 5,559 Adjusted EBITDA from reportable segments $ 49,709 $ 14,717 $ 64,426 Six months ended June 30, 2025 Ecoservices Advanced Materials & Catalysts Total Sales (1) $ 319,175 $ 43,151 $ 362,326 Less: (2) Cost of goods sold 227,455 22,223 Selling, general and administrative expenses 13,212 7,834 Other segment items (3) 212 276 Add: Adjusted EBITDA from the Zeolyst Joint Venture — 18,403 Adjusted EBITDA from reportable segments $ 78,296 $ 31,221 $ 109,517 26 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) Six months ended June 30, 2024 Ecoservices Advanced Materials & Catalysts Total Sales (1) $ 295,560 $ 47,797 $ 343,357 Less: (2) Cost of goods sold 190,970 26,984 Selling, general and administrative expenses 13,387 7,345 Other segment items (3) — 108 Add: Adjusted EBITDA from the Zeolyst Joint Venture — 12,486 Adjusted EBITDA from reportable segments $ 91,203 $ 25,846 $ 117,049 (1) The Company does not record its proportionate share of sales from the Zeolyst Joint Venture accounted for using the equity method as revenue and such sales are not consolidated within its results of operations. See Note 10 to these condensed consolidated financial statements for further information. The Company’s proportionate share of sales from the Zeolyst Joint Venture was $ 28,444 and $ 66,186 for the three and six months ended June 30, 2025, respectively. The Company’s proportionate share of sales from the Zeolyst Joint Venture was $ 29,024 and $ 52,505 for the three and six months ended June 30, 2024, respectively. (2) The significant expense categories and amounts align with the segment-level information that is regularly provided to the CODM. All lines exclude depreciation, amortization and other items as noted in the reconciliation below. (3) Other segment items include other operating (income) expense, foreign currency exchange (gains) losses and other (income) expense. The following table reconciles Adjusted EBITDA from reportable segments to income from continuing operations before income taxes: Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Adjusted EBITDA from reportable segments $ 63,489 $ 64,426 $ 109,517 $ 117,049 Less: Interest expense, net 11,117 12,895 22,127 26,304 Depreciation and amortization 23,944 21,624 47,066 43,557 Unallocated corporate expenses 7,754 7,532 14,876 14,613 Joint venture depreciation, amortization and interest 3,184 3,227 6,339 6,481 Amortization of investment in affiliate step-up 610 940 1,220 2,541 Debt modification and extinguishment costs — 4,560 960 4,560 Net loss (gain) on asset disposals 250 ( 34 ) 417 614 Foreign exchange (gain) loss ( 24 ) ( 99 ) 122 79 LIFO benefit ( 356 ) ( 1,547 ) ( 1,176 ) ( 2,671 ) Transaction and other related costs 2,661 140 4,528 198 Equity-based compensation 3,395 3,827 6,467 7,507 Restructuring, integration and business optimization expenses 1,030 159 1,167 385 Other 1,874 ( 173 ) 1,503 ( 894 ) Income before income taxes $ 8,050 $ 11,375 $ 3,901 $ 13,775 27 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) Capital expenditures for the Company’s reportable segments are shown in the following table: Six months ended June 30, 2025 2024 Capital expenditures: Ecoservices $ 37,182 $ 29,327 Advanced Materials & Catalysts (1) 7,679 4,200 Other (2) 4,664 3,122 Capital expenditures per the condensed consolidated statements of cash flows $ 49,525 $ 36,649 (1) Excludes the Company’s proportionate share of capital expenditures from the Zeolyst Joint Venture. (2) Includes corporate capital expenditures, the cash impact from changes in capital expenditures in accounts payable and capitalized interest. 18. Stock-Based Compensation: The Company has an equity incentive plan under which it grants common stock awards to employees, directors and affiliates of the Company. At June 30, 2025, 6,878,222 shares of common stock were available for issuance under the plan. The Company settles these awards through the issuance of treasury shares under its equity incentive plan. The Company has granted RSAs, RSUs and PSUs as part of its equity incentive compensation program. RSU During the six months ended June 30, 2025, the Company granted 985,551 RSUs under its equity incentive plan. Each RSU provides the recipient with the right to receive a share of common stock subject to graded vesting terms based on service, which for the awards granted during the six months ended June 30, 2025, generally requires approximately one year of service for members of the Company’s board of directors and approximately three years of service for employees. The value of the RSUs granted during the six months ended June 30, 2025 was based on the average of the high and low trading prices of the Company’s common stock on the NYSE on the preceding trading day, in accordance with the Company’s policy for valuing such awards. Compensation expense related to the RSUs is recognized on a straight-line basis over the respective vesting period. PSU 2025 Grants During the six months ended June 30, 2025, the Company granted 508,109 PSUs (at target) under its equity incentive plan. The PSUs granted during the six months ended June 30, 2025 provide the recipients with the right to receive shares of common stock dependent on 50 % of a Company-specific financial performance target and 50 % on the relative increase in the total shareholder return (“TSR”) goal (“the Performance measures”). The Performance measures are measured independently of each other, but achievement of both metrics is measured on the same three-year performance period from January 1, 2025 through December 31, 2027 (“Performance period”). Depending on the Company’s performance relative to the Performance measures, each PSU award recipient is eligible to receive a percentage of the target number of shares granted to the recipient, ranging from zero to 200 %. The PSUs, to the extent earned, will vest on the date the Compensation Committee of the Company’s Board of Directors (“Compensation Committee”) certifies the achievement of the Performance measures for the Performance period, which will occur subsequent to the end of the Performance period and after the Company files its annual consolidated financial statements for the year ending December 31, 2027. Achievement of the Company-specific financial performance target is measured based on the actual three-year cumulative results across the Performance period. The TSR goal is based on the Company’s actual TSR performance against companies in the S&P 1500 Specialty Chemicals Index over the Performance period. The TSR goal, which determines how much of the 50 % of the PSUs granted during 2025 may be earned, is considered a market condition as opposed to a vesting condition. Because a market condition is not considered a vesting condition, it is reflected in the grant date fair value of the award and the associated compensation cost based on the fair value of the award is recognized over the Performance period, regardless of whether the Company actually achieves the market condition or the level of achievement, as long as service is provided by the recipient. 28 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) The Company used a Monte Carlo simulation to estimate the $ 10.80 weighted average fair value of the awards granted, subject to the TSR goal during the six months ended June 30, 2025, with the following weighted average assumptions: Expected dividend yield — % Risk-free interest rate 4.19 % Expected volatility 40.39 % Expected term (in years) 2.90 2022 Grants In February 2025, the Compensation Committee certified the achievement of the performance metrics for the three-year period ended December 31, 2024, related to the PSUs granted during the year ended December 31, 2022. The PSUs granted during the year ended December 31, 2022 provide the recipients with the right to receive shares of common stock dependent on the achievement of a TSR goal and are generally subject to the provision of service through the vesting date of the award. The TSR goal was based on the Company’s actual TSR percentage increase over the performance period. The awards vested during the six months ended June 30, 2025 with no percentage of the TSR goal earned. Award Activity The following table summarizes the activity for the Company’s RSUs and PSUs for the six months ended June 30, 2025: Restricted Stock Units Performance Stock Units Number of units Weighted average grant date fair value (per share) Number of units Weighted average grant date fair value (per share) Nonvested as of December 31, 2024 1,977,373 $ 9.37 1,353,409 (1) $ 11.10 Granted 985,551 $ 7.76 508,109 $ 9.28 Vested ( 1,053,456 ) $ 9.53 — $ — Forfeited ( 100,814 ) $ 9.07 ( 187,495 ) $ 9.30 Nonvested as of June 30, 2025 1,808,654 $ 8.42 1,674,023 (1) $ 10.75 (1) Based on target. During the six months ended June 30, 2025, the Company did not grant any RSAs. Cash proceeds received by the Company from the exercise of stock options were not material for the six months ended June 30, 2025. Stock-Based Compensation Expense For the three months ended June 30, 2025 and 2024, stock-based compensation expense for the Company was $ 3,395 and $ 3,827 , respectively. The associated income tax benefit based on the applicable statutory rate recognized in the condensed consolidated statements of income for the three months ended June 30, 2025 and 2024 was $ 809 and $ 939 , respectively. For the six months ended June 30, 2025 and 2024, stock-based compensation expense for the Company was $ 6,467 and $ 7,507 , respectively. The associated income tax benefit based on the applicable statutory rate recognized in the condensed consolidated statements of income for the six months ended June 30, 2025 and 2024 was $ 1,579 and $ 1,841 , respectively. As of June 30, 2025, unrecognized compensation cost of $ 11,333 for RSUs and $ 7,264 for PSUs are considered probable of vesting and the weighted-average period over which these costs are expected to be recognized at June 30, 2025 was 1.81 years for the RSUs and 1.99 years for the PSUs. 29 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) 19. Earnings per Share: Basic earnings per share is calculated as income available to common stockholders, divided by the weighted average number of common shares outstanding during the period. The weighted average number of common shares outstanding during the period for the computation of basic earnings per share excludes RSAs that have legally been issued but are nonvested during the period, as the sale of these shares is prohibited pending satisfaction of certain vesting conditions by the award recipients in order to earn the rights to the shares. Diluted earnings per share is calculated as income available to common stockholders, divided by the weighted average number of common and potential common shares outstanding during the period, if dilutive. Potential common shares reflect (1) unvested RSAs and RSUs with service vesting conditions, (2) PSUs with vesting conditions considered probable of achievement and (3) options to purchase common stock, all of which have been included in the diluted earnings per share calculation using the treasury stock method. The reconciliation from basic to diluted weighted average shares outstanding is as follows: Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Weighted average shares outstanding – Basic 116,232,528 116,912,332 116,745,476 116,935,708 Dilutive effect of unvested common shares and RSUs with service conditions, PSUs considered probable of vesting and assumed stock option exercises and conversions 302,532 722,957 298,985 609,532 Weighted average shares outstanding – Diluted 116,535,060 117,635,289 117,044,461 117,545,240 Basic and diluted income per share are calculated as follows: Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Numerator: Net income $ 5,986 $ 8,295 $ 2,389 $ 9,516 Denominator: Weighted average shares outstanding – Basic 116,232,528 116,912,332 116,745,476 116,935,708 Weighted average shares outstanding – Diluted 116,535,060 117,635,289 117,044,461 117,545,240 Net income per share: Basic income per share $ 0.05 $ 0.07 $ 0.02 $ 0.08 Diluted income per share $ 0.05 $ 0.07 $ 0.02 $ 0.08 The table below presents the details of the Company’s weighted average equity-based awards outstanding during each respective period that were excluded from the calculation of diluted earnings per share: Three months ended June 30, Six months ended June 30, 2025 2024 2025 2024 Anti-dilutive RSUs and PSUs 1,535,776 431,837 1,158,741 481,281 Anti-dilutive stock options 367,100 367,100 367,100 367,100 Certain stock options to purchase shares of common stock were excluded from the computation of diluted earnings per share for the respective periods because the options’ exercise price was greater than the average market price of the common shares. These stock options and anti-dilutive awards are not included in the dilution calculation, as their inclusion would have the effect of increasing diluted income per share. 30 Table of Contents ECOVYST INC. AND SUBSIDIARIES NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts) (unaudited) 20. Supplemental Cash Flow Information: The following table presents supplemental cash flow information for the Company: Six months ended June 30, 2025 2024 Cash paid during the period for: Income taxes, net of refunds $ 8,837 $ 16,439 Interest (1) 23,370 33,155 Non-cash investing activity: Capital expenditures acquired on account but unpaid as of the period end 2,135 784 Non-cash financing activity: Accrued excise tax on share repurchases (Note 5) 151 — Right-of-use assets obtained in exchange for new lease liabilities (non-cash): Operating leases 8,863 2,957 (1) Cash paid for interest is shown net of capitalized interest and includes the cash received or paid on the Company’s interest rate cap agreements designated as cash flow hedges for the periods presented (see Note 12 to these condensed consolidated financial statements for details). 21. Subsequent Events: T he Company has evaluated subsequent events since the balance sheet date and determined that there are no additional items to disclose. 31 Table of Contents