What changed in this filing

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Item 1. Financial Statements

2026-05-08 compared with 2025-11-07 · 115 added, 199 removed, 590 unchanged (35% of the section changed)

3 unchanged sentences

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions, except share and per share amounts) (Unaudited) (Unaudited) (Unaudited) (Unaudited)

(Dollars in millions, except share and per share amounts) (Unaudited) (Unaudited)

Net sales $ 455.3 $ 456.5

3 unchanged sentences

Impairment and restructuring 7.8 20.0

(Gain) loss on sale of assets ( 0.1 ) 9.7 ( 0.4 ) 9.7

(Gain) on sale of assets ( 4.3 ) ( 0.3 )

Operating profit 22.0 27.0

2 unchanged sentences

Loss on pension settlement 0.0 29.0

Income before income taxes 35.8 29.6 42.5 84.0

Income tax provision 12.0 10.6 16.2 25.2

Net income 23.8 19.0 26.3 58.8

Net loss attributable to noncontrolling interests 0.0 ( 3.8 ) 0.0 ( 3.8 )

Net income attributable to Koppers $ 23.8 $ 22.8 $ 26.3 $ 62.6

Earnings per common share attributable to Koppers common shareholders:

Income (loss) before income taxes 7.9 ( 17.2 )

Income tax provision (benefit) 0.8 ( 3.3 )

Net income (loss) $ 7.1 $ ( 13.9 )

Earnings (loss) per common share:

Basic $ 0.36 $ ( 0.68 )

6 unchanged sentences

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions) (Unaudited) (Unaudited) (Unaudited) (Unaudited)

Net income $ 23.8 $ 19.0 $ 26.3 $ 58.8

(Dollars in millions) (Unaudited) (Unaudited)

Net income (loss) $ 7.1 $ ( 13.9 )

Changes in other comprehensive income (loss):

1 unchanged sentence

Cash flow hedges, net of tax of $ 0.3 and $ 1.3

( 1.1 ) ( 7.5 ) 3.3 2.9

Pension adjustments, net of tax of $ 0.0 and $ 8.3

0.1 0.3 25.3 1.0

Comprehensive income $ 2.4 $ 23.4

Comprehensive loss attributable to noncontrolling interests 0.0 ( 3.8 ) 0.0 ( 3.8 )

Comprehensive income attributable to Koppers $ 21.7 $ 29.4 $ 83.6 $ 66.9

The accompanying notes are an integral part of these condensed consolidated financial statements.

1 unchanged sentence

CONDENSED CONSOLIDATED BALANCE SHEET

September 30, 2025 December 31, 2024

March 31, 2026 December 31, 2025

(Dollars in millions, except share and per share amounts) (Unaudited)

42 unchanged sentences

CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS

Nine Months Ended September 30,

Three Months Ended March 31,

(Dollars in millions) (Unaudited) (Unaudited)

Cash provided by (used in) operating activities:

Net income $ 26.3 $ 58.8

Net income (loss) $ 7.1 $ ( 13.9 )

Adjustments to reconcile net income to net cash provided by operating activities:

4 unchanged sentences

Non-cash interest expense 0.9 0.9

(Gain) loss on sale of assets ( 0.3 ) 9.4

(Gain) on sale of assets ( 4.3 ) ( 0.6 )

Insurance proceeds 0.0 ( 2.2 )

2 unchanged sentences

Change in other liabilities ( 0.3 ) 4.0

Cloud-based software implementation costs, net of amortization 0.1 ( 0.9 )

Other - net 0.1 ( 0.6 )

5 unchanged sentences

Other working capital ( 2.3 ) ( 2.2 )

Net cash provided by operating activities 77.4 44.7

Net cash provided by (used in) operating activities 46.3 ( 22.7 )

Cash (used in) provided by investing activities:

Capital expenditures ( 11.4 ) ( 14.3 )

Acquisitions 0.0 ( 99.4 )

Insurance proceeds 0.0 2.2

6 unchanged sentences

Repayments of credit facility ( 165.5 ) ( 94.1 )

Borrowings of long-term debt 0.0 100.0

Repayments of long-term debt ( 1.2 ) ( 1.2 )

1 unchanged sentence

Repurchases of Common Stock ( 29.0 ) ( 19.1 )

Payment of debt issuance costs ( 2.6 ) ( 0.9 )

Dividends paid ( 4.7 ) ( 4.6 )

Dividends paid and return of capital to noncontrolling interests ( 2.2 ) ( 1.6 )

Net cash (used in) provided by financing activities ( 31.0 ) 28.7

Effect of exchange rate changes on cash 0.0 1.0

Net decrease in cash and cash equivalents ( 6.0 ) ( 22.0 )

Net increase (decrease) in cash and cash equivalents 4.8 ( 10.6 )

Cash and cash equivalents at beginning of period 38.0 43.9

3 unchanged sentences

Accrued capital expenditures 0.4 3.5

Non-cash consideration for sale of assets or acquisition 0.6 2.6

The accompanying notes are an integral part of these condensed consolidated financial statements.

2 unchanged sentences

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions, except per share amounts) (Unaudited) (Unaudited) (Unaudited) (Unaudited)

(Dollars in millions, except per share amounts) (Unaudited) (Unaudited)

Total equity – beginning of period $ 574.3 $ 489.0

8 unchanged sentences

Balance at beginning of period 539.4 490.3

Net income attributable to Koppers 23.8 22.8 26.3 62.6

Common Stock dividends

($ 0.08 , $ 0.07 , $ 0.24 and $ 0.21 per share)

Net income (loss) 7.1 ( 13.9 )

Common Stock dividends ($ 0.09 and $ 0.08 per share)

( 1.9 ) ( 1.9 )

Return of capital to noncontrolling interests ( 0.3 ) 0.0

Balance at end of period 544.3 474.5

3 unchanged sentences

Cash flow hedges, net of tax (1)

( 1.1 ) ( 7.5 ) 3.3 2.9

Pension adjustments, net of tax (2)

0.1 0.3 25.3 1.0

Balance at end of period ( 65.8 ) ( 83.3 )

5 unchanged sentences

Balance at beginning of period 0.3 0.3

Net loss attributable to noncontrolling interests 0.0 ( 3.8 ) 0.0 ( 3.8 )

Currency translation adjustment ( 0.3 ) 0.0

Balance at end of period 0.0 0.3

10 unchanged sentences

Common Stock Outstanding 19,230 20,004

(1) Amounts reclassified from accumulated other comprehensive income to net income related to derivative financial instruments, net of tax, were $ 1.1 million and $ 3.3 million during the three months ended September 30, 2025 and 2024, respectively, and $ 2.6 million and $ 9.6 million during the nine months ended September 30, 2025 and 2024, respectively.

(1) Amounts reclassified from accumulated other comprehensive income to net income related to derivative financial instruments, net of tax, were $ 0.4 million and $ 0.6 million during the three months ended March 31, 2026 and 2025, respectively.

(2) Amounts reclassified from accumulated other comprehensive income to net income consist of amounts shown for pension adjustments.

12 unchanged sentences

The financial information included herein should be read in conjunction with our audited consolidated financial statements and related notes included in our Annual Report on Form 10-K as of and for the year ended December 31, 2025.

New Accounting Pronouncements – In December 2023, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No.

2023-09, Income Taxes (Topic 740):

Improvements to Income Tax Disclosures.

This ASU updates income tax disclosures by requiring annual disclosures of consistent categories and greater disaggregation of information in the rate reconciliation and income taxes paid disaggregated by jurisdiction.

2023-09 is effective for fiscal years beginning after December 15, 2024.

The amendments should be applied either prospectively to financial statements issued for reporting periods after the effective date of this ASU or retrospectively to any and all prior periods presented in the financial statements.

We are currently evaluating this ASU to determine its impact on our disclosures.

In November 2024, the FASB issued ASU No.

New Accounting Pronouncements – In November 2024, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No.

2024-03, Income Statement - Reporting Comprehensive Income (Topic 220):

6 unchanged sentences

We are currently evaluating this ASU to determine its impact on our disclosures.

Acquisitions and Restructuring

Acquisition – On April 1, 2024, we completed our acquisition of substantially all of the assets of Brown Wood Preserving Company, Inc.

and certain of its affiliates (Brown Wood) for approximately $ 100 million in cash, after post-closing working capital adjustments.

We financed the acquisition with cash and available borrowings under our Credit Facility (as defined in Note 11 – Debt).

Brown Wood is a utility pole treating business with principal operating locations in Alabama and Mississippi.

The business we acquired, as well as the sales function, has been operationally integrated into our existing network of utility pole plants and distribution yards.

We believe the acquisition, which is included in our RUPS segment (as defined in Note 7 – Segment Information), increased our presence in existing markets and offers an attractive entry point to new geographic markets for our utility pole business.

Transaction costs, revenue and profit related to the acquisition were not material for the year ended December 31, 2024.

We accounted for the transaction as a business combination.

The following table summarizes the purchase price and estimated fair value of assets acquired and liabilities assumed as of April 1, 2024.

(Dollars in millions)

Cash consideration (1)

Accounts receivable 5.2

Inventories 14.4

Property, plant and equipment 28.0

Customer relationship intangible assets 32.2

Operating lease right-of-use assets 2.4

Fair value of assets acquired 82.2

Accounts payable and accrued liabilities 3.1

Current operating lease liabilities 1.1

Operating lease liabilities 1.3

Fair value of liabilities assumed 5.5

Goodwill $ 25.3

(1) The difference between total cash consideration and cash paid in the prior year condensed consolidated statement of cash flows relates to the settlement of pre-existing relationships with our PC segment (as defined in Note 7 - Segment Information) and Brown Wood, as the settlement was deemed additional consideration.

The customer relationship intangible assets have a useful life of 15 years and are amortized on a straight-line basis.

Goodwill has been allocated to the Company’s RUPS segment.

The Company expects the goodwill recognized to be deductible for tax purposes.

Recognized goodwill is attributable to the expected synergies and other intangible assets that do not qualify for separate recognition.

Restructuring

Plant Closures and Restructuring – The following table summarizes restructuring activities:

Three Months Ended September 30, 2025 Nine Months Ended September 30, 2025 Cumulative Total

Three Months Ended March 31, 2026 Three Months Ended March 31, 2025 Cumulative Total

(Dollars in millions)

5 unchanged sentences

Consulting services 2.4 2.9 18.3

Other restructuring costs 4.9 0.0 4.9

Total impairment and restructuring $ 7.8 $ 20.0 $ 73.0

7 unchanged sentences

locations, which is intended to streamline operations and reduce costs.

This workforce reduction program will result in the reallocation of people and resources, which include voluntary and involuntary reductions in employees and is expected to extend through the end of 2025.

We have incurred and will continue to incur pre-tax restructuring charges including but not limited to employee severance and related benefit costs.

At this time, we have not fully defined all of the specific cost reduction actions to be implemented and therefore are unable to provide a cost estimate or range of cost estimates associated with this action.

Consulting Services – We have incurred and will continue to incur consulting and other professional service fees starting with a comprehensive assessment of each of our businesses and functions which was completed during the third quarter of 2025.

This workforce reduction program resulted in the reallocation of people and resources, included voluntary and involuntary reductions in employees and ended in the fourth quarter of 2025.

We then started the multi-year company-wide transformative project to design and implement changes that we believe will enable us to reach our full potential and improve profitability, modernize business processes and pursue portfolio realignment, if necessary.

The following table includes details of plant closures and restructuring liabilities:

Other Restructuring Costs – In the first quarter of 2026, we announced plans to idle two of our facilities.

Consolidating production of these facilities will help us optimize our network, better align capacity with demand, reduce operating costs and strengthen the long-term competitiveness of our operations.

We made the decision to idle production activities at our Utility and Industrial Products facility in Vance, Alabama, effective in February 2026.

Substantially all production handled at this location was transitioned to our Kennedy, Alabama plant.

These facilities were located within 60 miles of each other and served the same market which resulted in plant underutilization, redundancy and higher operating costs.

We also announced our plan to idle production activities at our Railroad Products and Services facility in Florence, South Carolina due to lower overall future forecasted demand from the facility's largest customer.

We expect to ramp down production at Florence over the next several months with plant idling activities to be completed by November 2026.

During this time period, we will transition incremental production to our facility in Guthrie, Kentucky.

The following table includes details of our phthalic anhydride shutdown and workforce reduction program liabilities:

Phthalic Anhydride Shutdown Workforce Reduction Program

3 unchanged sentences

Cash paid ( 8.1 ) ( 5.0 )

Liability at September 30, 2025 $ 4.5 $ 1.9

Liability at December 31, 2025 $ 5.4 $ 0.6

Accrual 0.5 0.0

Cash paid ( 0.7 ) ( 0.4 )

Liability at March 31, 2026 $ 5.2 $ 0.2

KCCC Liquidation – In July 2024, Koppers and Tangshan Iron & Steel Group Co.

(TISCO) signed an agreement to effectuate the ultimate liquidation of Koppers (China) Carbon & Chemical Company Limited (KCCC), which ceased operations in 2015.

During the first quarter of 2025, TISCO assumed the remaining assets, including land, and liabilities of KCCC, which resulted in cash paid of approximately $ 7.6 million.

KCCC is owned 60 percent by a wholly owned subsidiary of Koppers and 40 percent by TISCO.

KRS Sale – On August 29, 2025, we sold our railroad bridge services business, Koppers Railroad Structures Inc., which was previously included in our RUPS segment.

The liquidation of KCCC was completed in February 2026 which resulted in a non-cash gain of approximately $ 4 million during the first quarter of 2026.

Fair Value Measurements

The following table presents the estimated fair values and the related carrying amounts of our financial instruments:

September 30, 2025 December 31, 2024

March 31, 2026 December 31, 2025

Fair Value Carrying Value Fair Value Carrying Value

9 unchanged sentences

We utilize derivative instruments to manage exposures to risks that have been identified, measured and are capable of being mitigated.

The primary risks that we manage by using derivative instruments are commodity price risk associated with copper, fuel oil, foreign currency exchange risk, principally the U.S.

dollar and British pound sterling, and interest rate risk associated with variable rate borrowings.

The primary risks that we manage by using derivative instruments are commodity price risk associated with copper, fuel oil, foreign currency exchange risk and interest rate risk associated with variable rate borrowings.

Generally, we enter into master netting arrangements with the counterparties and offset net derivative positions with the same counterparties.

8 unchanged sentences

Generally, we will not hedge cash flow exposures for durations longer than 36 months and we have hedged certain volumes of copper through the end of 2026.

We designate certain of our commodity swaps as cash flow hedges of forecasted purchases of commodities.

Prior to July 2025, we designated certain of our commodity swaps as cash flow hedges of forecasted purchases of commodities.

For those commodity swaps where hedge accounting is not elected, the unrealized gain or loss on the derivative is reported as cost of sales in the condensed consolidated statement of operations.

During the third quarter of 2025, our quarterly effectiveness assessment identified that our hedging contracts had fallen outside the required effectiveness thresholds to continue cash flow hedge accounting.

This was caused by the increased and cumulative volatility in the market prices for copper during the first half of 2025.

Accordingly, we prospectively discontinued cash flow hedge accounting in the third quarter of 2025.

As of March 31, 2026, $ 2.0 million remained in accumulated other comprehensive income and will be released to income as the underlying hedge contracts mature through December 2026.

Subsequent changes in the fair value of these copper swap contracts will continue to be recognized immediately in earnings until such swap contracts settle or mature.

We enter into heating oil swap contracts to manage price risk associated with fuel oil purchases for our plant operations and certain raw material requirements.

1 unchanged sentence

These swap contracts are not designated as hedges so the unrealized gain or loss on the derivative is reported as cost of sales in the condensed consolidated statement of operations.

As of September 30, 2025 and December 31, 2024, we had contracts totaling 3.4 million and 3.5 million gallons, respectively.

As of March 31, 2026 and December 31, 2025, we had contracts totaling 3.6 million and 3.8 million gallons, respectively.

We enter into foreign currency forward contracts to manage foreign currency risk associated with our receivable and payable balances in addition to foreign-denominated sales.

6 unchanged sentences

The fair value of the outstanding derivative contracts recorded in the balance sheet are as follows:

September 30, 2025

March 31, 2026

Copper Swap Contracts Heating Oil Contracts Foreign Currency Forward

12 unchanged sentences

Derivative contracts $ 31.4 $ 0.0 $ 0.0 $ 0.1 $ 31.5

Other assets 0.0 0.0 0.0 1.0 1.0

Accrued liabilities 0.0 ( 0.4 ) 0.0 ( 2.2 ) ( 2.6 )

Other long-term liabilities 0.0 0.0 0.0 ( 1.1 ) ( 1.1 )

Net (liability) asset on balance sheet $ ( 8.9 ) $ ( 0.5 ) $ ( 0.9 ) $ 0.4 $ ( 9.9 )

Accumulated other comprehensive loss, net of tax $ ( 2.0 ) $ 0.0 $ 0.0 $ ( 0.3 ) $ ( 2.3 )

Net asset (liability) on balance sheet $ 31.4 $ ( 0.4 ) $ 0.0 $ ( 3.2 ) $ 27.8

Accumulated other comprehensive gain (loss), net of tax $ 2.5 $ 0.0 $ 0.0 $ ( 2.4 ) $ 0.1

We estimate that unrealized gains, net of tax, for commodity price hedging of $ 2.0 million and unrealized losses, net of tax, for interest rate swaps of $ 0.9 million, respectively, will be reclassified from other comprehensive income into earnings over the next twelve months .

This was caused by the increased and cumulative volatility in the market prices for copper during the first half of 2025.

Accordingly, we prospectively discontinued cash flow hedge accounting in the third quarter of 2025.

At the time we discontinued cash flow hedge accounting, accumulated other comprehensive income contained a pre-tax gain of $ 5.8 million ($ 4.4 million net of taxes).

This amount will be released to income as the underlying hedge contracts mature through December 2026.

As a result of discontinuing cash flow hedge accounting, a net cumulative pre-tax unrealized gain of $ 3.2 million was recorded in earnings during the three months ended September 30, 2025.

Subsequent changes in the fair value of these copper swap contracts will continue to be recognized immediately in earnings until such swap contract settles or matures.

The unrealized gain (loss) from our hedging contracts where hedge accounting was not elected is as follows:

The unrealized gain (loss) from our hedging contracts is as follows:

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions)

3 unchanged sentences

Copper Swap Contracts – We had outstanding copper swap contracts of the following amounts:

Units Outstanding (in Pounds) Net Fair Value – Asset (Liability)

September 30, 2025 December 31, 2024 September 30, 2025 December 31, 2024

Units Outstanding (in Pounds) Net Fair Value – Asset

March 31, 2026 December 31, 2025 March 31, 2026 December 31, 2025

(Amounts in millions)

Cash flow hedges 0.0 20.7 $ 0.0 $ ( 2.7 )

Not designated as hedges 23.7 25.6 $ 23.4 $ 31.4

Total 29.4 47.4 $ 12.4 $ ( 8.9 )

Foreign Currency Forward Contracts – The net currency units outstanding for contracts were:

September 30, 2025 December 31, 2024

March 31, 2026 December 31, 2025

(In millions)

4 unchanged sentences

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions, except share and per share amounts)

Net income attributable to Koppers $ 23.8 $ 22.8 $ 26.3 $ 62.6

Net income (loss) $ 7.1 $ ( 13.9 )

Weighted average common shares outstanding (in thousands):

7 unchanged sentences

earnings per common share 135 1,110

On November 6, 2025, we declared a quarterly dividend of $ 0.08 per common share, payable on December 16, 2025 to shareholders of record as of November 28, 2025.

On May 7, 2026, we declared a quarterly dividend of $ 0.09 per common share, payable on June 15, 2026 to shareholders of record as of May 29, 2026.

Stock-based Compensation

The board of directors granted restricted stock units and performance stock units (collectively, the stock units) to certain employee participants in January 2026.

No stock options have been granted since 2022.

Most grants of restricted stock units vest in three or four years .

Performance stock units vest based upon either a performance condition or a market condition.

Performance stock units granted with a performance condition have a cumulative three-year performance objective based on adjusted EBITDA (see Note 7 – Segment Information).

For units granted in 2025 and prior, performance stock units granted with a performance condition have a cumulative three-year performance objective based on adjusted EBITDA (see Note 7 – Segment Information).

For units granted in 2026, performance stock units granted with a performance condition have a cumulative adjusted earnings per share objective and a cumulative free cash flow objective, each weighted at 50 percent, with adjusted EBITDA margin used as a performance modifier (i.e.

plus or minus 25 percent of actual earned performance).

For performance stock units granted with a market condition, the applicable objective is based on our total shareholder return relative to the Standard & Poor’s SmallCap 600 Materials Index and has multi-year performance objectives.

Both types of performance stock units have a three-year period for vesting, if the applicable performance objectives are achieved.

The number of performance stock units granted represents the target award and participants have the ability to earn between zero and 200 percent of the target award based upon actual performance.

The number of performance stock units granted represents the target award and participants have the ability to earn between zero and 200 percent of the target award based upon actual performance for units granted in 2025 and prior, and between zero and 250 percent of the target award based upon actual performance for units granted in 2026.

If minimum performance criteria are not achieved, no performance stock units will vest.

For the awards granted in January 2026, target shares for units with a market condition totaled 124,878 and target shares for units with a performance condition totaled 137,844 .

The above awards include 135,795 target shares for performance stock units with a market condition and 30,873 restricted stock units that were issued in lieu of a portion of the cash incentive award that could be earned during 2025 for certain participants.

These stock units vest over a three-year period.

Combined with other changes to the cash incentive award program, including the change in which certain participants had a portion of their annual award converted into a three-year stock unit award to promote retention, we expect to save approximately $ 5 million in expenses for 2025 with such amount being recognized over the subsequent two years .

We calculated the fair value of the performance stock unit awards with a market condition on the date of the grant using assumptions listed below.

5 unchanged sentences

Look-back period in years 3.00

Fair value cap per share $ 65.00

Grant date fair value per share $ 27.97

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Credited from dividends 371 643 1,014 $ 28.20

Performance share adjustment 0 28,505 28,505 $ 28.93

Vested ( 209,958 ) ( 329,924 ) ( 539,882 ) $ 33.53

Forfeited ( 20,167 ) ( 16,761 ) ( 36,928 ) $ 36.95

Non-vested at September 30, 2025 517,019 788,112 1,305,131 $ 35.65

Non-vested at March 31, 2026 520,011 679,416 1,199,427 $ 32.60

The following table shows a summary of the status and activity of stock options:

7 unchanged sentences

Exercised ( 70,178 ) $ 19.26

Outstanding at September 30, 2025 514,933 $ 28.83 3.73 $ 1.6

Exercisable at September 30, 2025 491,894 $ 28.68 3.61 $ 1.6

Outstanding at March 31, 2026 436,952 $ 30.12 3.59 $ 4.1

Exercisable at March 31, 2026 436,952 $ 30.12 3.59 $ 4.1

The following table presents total stock-based compensation expense recognized in the condensed consolidated statement of operations:

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions)

1 unchanged sentence

Less related income tax benefit 1.1 2.0

Decrease in net income attributable to Koppers $ 1.5 $ 3.7 $ 7.2 $ 11.6

Decrease in net income $ 2.8 $ 4.6

Segment Information

8 unchanged sentences

We also operate a business related to the recovery of used crossties, serving the same customer base as our North American railroad business.

We sold our railroad bridge services business during the third quarter of 2025.

See Note 2 - Acquisitions and Restructuring.

Our PC segment develops, manufactures, and markets wood preservation chemicals and wood treatment technologies and services to a diverse range of end-markets including residential, industrial, commercial construction and agricultural applications.

3 unchanged sentences

Naphthalene is used as a surfactant in the production of concrete.

Our CMC segment ceased production of phthalic anhydride in the second quarter of 2025.

See Note 2 – Acquisitions and Restructuring.

Our measure of segment profitability is adjusted income before interest expense, income taxes, depreciation, amortization and certain non-cash and/or non-recurring items that do not contribute directly to management’s evaluation of our operating results (as defined by us, adjusted EBITDA).

These non-cash and/or non-recurring items typically include last-in, first-out (LIFO) inventory effects, impairment, restructuring and plant closure costs, significant gains or losses on sale of assets, mark-to-market commodity hedging, acquisition-related charges, amortization of cloud-based software implementation costs and other unusual items.

These non-cash and/or non-recurring items typically include last-in, first-out (LIFO) inventory effects, impairment, restructuring and plant closure costs, significant gains or losses on sale

of assets, mark-to-market commodity hedging, acquisition-related charges, amortization of cloud-based software implementation costs and other unusual items.

This presentation is consistent with how our chief operating decision maker evaluates the results of operations and makes strategic decisions about the business.

In addition, adjusted EBITDA is the primary measure used to determine the level of achievement of management’s short-term incentive goals and related payout, as well as one of the measures used to determine performance and related payouts for certain performance share units granted to management.

For these reasons, we believe that adjusted EBITDA represents the most relevant measure of segment profit and loss.

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Contract Balances – The timing of revenue recognition results in both billed accounts receivable and unbilled receivables, both classified as accounts receivable, net of allowance within the condensed consolidated balance sheet.

Contract assets of $ 3.4 million and $ 7.6 million are recorded within accounts receivable, net of allowance within the condensed consolidated balance sheet as of September 30, 2025 and December 31, 2024, respectively.

Contract assets of $ 1.7 million and $ 1.8 million are recorded within accounts receivable, net of allowance within the condensed consolidated balance sheet as of March 31, 2026 and December 31, 2025, respectively.

Segment Revenues for Significant Product Lines

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions)

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Pitch and related products $ 70.2 $ 65.2

Phthalic anhydride, naphthalene and other chemicals 7.9 29.2 43.9 98.2

Carbon black feedstock and distillates 13.8 14.2

Naphthalene, phthalic anhydride, and other chemicals 9.2 21.2

Total Carbon Materials and Chemicals $ 93.2 $ 100.6

2 unchanged sentences

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions)

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Total $ 49.3 $ 55.5

(1) Other (income) expense amounts primarily relate to miscellaneous (income) expense and the adjustments to reconcile to adjusted EBITDA such as acquisition-related charges, mark-to-market commodity hedging and LIFO inventory effects.

(1) Other (income) expense amounts primarily relate to miscellaneous (income) expense and the adjustments to reconcile to adjusted EBITDA such as acquisition-related charges, LIFO inventory effects and mark-to-market commodity hedging.

Segment Adjusted EBITDA

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions)

4 unchanged sentences

Items excluded from the determination of segment profit:

LIFO benefit (expense) (1)

4.8 1.2 7.3 ( 2.9 )

Impairment, restructuring and plant closure costs (2)

( 10.2 ) ( 0.4 ) ( 47.8 ) ( 0.4 )

Gain (loss) on sale of assets 0.1 ( 9.7 ) 0.4 ( 9.7 )

Mark-to-market commodity hedging gains 4.9 0.0 14.7 3.0

Acquisition inventory step-up amortization ( 0.3 ) 0.0

1 unchanged sentence

( 0.5 ) ( 0.3 )

Gain on sale of assets 4.3 0.3

Impairment, restructuring and plant closure costs (1)

( 7.8 ) ( 20.0 )

LIFO benefit (2)

Mark-to-market commodity hedging (losses) gains ( 3.9 ) 9.1

Pension settlement and expense 0.0 ( 29.0 )

Interest expense ( 16.7 ) ( 20.2 ) ( 50.6 ) ( 57.9 )

Depreciation and amortization ( 19.4 ) ( 18.0 )

Interest expense ( 15.0 ) ( 16.6 )

Income tax provision ( 0.8 ) 3.3

Net income $ 23.8 $ 19.0 $ 26.3 $ 58.8

Net income (loss) $ 7.1 $ ( 13.9 )

(1) See Note 2 - Restructuring.

(2) The LIFO expense adjustment removes the entire impact of LIFO and effectively reflects the results as if we were on a first-in, first-out (FIFO) inventory basis.

(2) See Note 2 - Acquisitions and Restructuring.

Other Segment Disclosures

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions)

15 unchanged sentences

Segment Assets

September 30, 2025 December 31, 2024

March 31, 2026 December 31, 2025

(Dollars in millions)

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Railroad and Utility Products and Services $ 156.5 $ 156.4

$ 144.6 $ 145.6

Performance Chemicals 172.9 173.0

Total $ 329.4 $ 329.4

(1) The decrease in RUPS goodwill was due primarily to the sale of KRS as described in Note 2 - Acquisitions and Restructuring.

Effective Tax Rate – The income tax provision for interim periods is comprised of an estimated annual effective income tax rate applied to current year ordinary income and tax associated with discrete items.

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federal statutory tax rate due to:

September 30,

Federal income tax rate 21.0 % 21.0 %

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Nondeductible expenses 1.1 2.2

GILTI inclusion, net of foreign tax credits 1.4 ( 0.2 )

Change in tax contingency reserves 0.2 0.3

tax on international operations, net of credits ( 0.2 ) 0.2

Estimated annual effective income tax rate 27.7 % 30.7 %

Income taxes as a percentage of pretax income were 33.5 percent and 38.1 percent for the three and nine months ended September 30, 2025, respectively, and 35.8 percent and 30.0 percent for the three and nine months ended September 30, 2024, respectively.

The effective income tax rate for the three months ended September 30, 2025 was slightly higher than the estimated annual effective income tax rate due to additional tax expense recognized in the quarter as a result of increases in the estimated annual effective income tax rate from the prior period.

The effective income tax rate for the nine months ended September 30, 2025 was significantly higher than the respective estimated annual effective income tax rate due to the loss on pension settlement, which has been treated as a discrete item.

The effective income tax rates for the three months and nine months ended September 30, 2024 were higher than the respective estimated annual effective income tax rate due to the loss on the sale of KCCC's assets.

This loss has no corresponding tax benefit since KCCC will not have future income to offset this loss.

Income taxes as a percentage of pretax income were 10.1 percent and 19.2 percent for the three months ended March 31, 2026 and 2025, respectively.

The effective income tax rate for the three months ended March 31, 2026 was lower than the 2026 estimated annual effective income tax rate due to the liquidation of our former coal tar distillation facility located in China.

This one-time non-cash gain did not have any associated income tax expense.

The effective income tax rate for the three months ended March 31, 2025 was lower than the 2025 estimated annual effective income tax rate due to the loss on pension settlement which was treated as a discrete item in the first quarter tax provision.

During the year, management regularly updates estimates of pre-tax income and income tax expense based on changes in pre-tax income projections by taxable jurisdiction, repatriation of foreign earnings, unrecognized tax benefits and other tax matters.

To the extent that actual results vary from these estimates, the actual annual effective income tax rate at the end of the year could be materially different from the estimated annual effective income tax rate as of the nine months ended September 30, 2025.

On July 4, 2025, H.R.

budget reconciliation bill, was signed into law.

We have analyzed the various components of the bill and incorporated the effects into our estimated annual effective income tax rate.

We have determined that the financial statement impact of the budget reconciliation bill is not material and the effect on our estimated annual effective income tax rate is not material.

The primary impact of the budget reconciliation bill will be an increase of our current year interest expense deduction under Section 163(j) and an increase in our current year tax depreciation due to the extension of the bonus depreciation rules.

Effective January 1, 2024, certain jurisdictions in which we operate have enacted legislation that is consistent with one or more Organization for Economic Co-operation and Development Global Anti-Base Erosion Model Rules (commonly referred to as "Pillar Two").

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income tax examinations by tax authorities for years prior to 2020.

As of September 30, 2025 and December 31, 2024, unrecognized tax benefits of $ 1.0 million for both periods would affect the effective tax rate if recognized.

As of March 31, 2026 and December 31, 2025, unrecognized tax benefits of $ 1.1 million for both periods would affect the effective tax rate if recognized.

We do not anticipate material changes to the amount of unrecognized tax benefits within the next twelve months.

September 30, 2025 December 31, 2024

March 31, 2026 December 31, 2025

(Dollars in millions)

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During 2024, we initiated a plan to terminate our largest United States qualified pension plan.

In February 2025, we completed the irrevocable transfer of $ 86.4 million of pension liabilities and an equal amount of pension assets to an insurance company.

In 2025, we completed the irrevocable transfer of $ 84.5 million of pension liabilities and an equal amount of pension assets to an insurance company.

In order to achieve this transfer, additional cash funding of approximately $ 12 million was required in 2025.

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The timing of the conversion to a buy-out policy and related recognition of the estimated pension settlement loss has been impacted by a ruling from the High Court of Justice in the United Kingdom in the case of Virgin Media Limited v NTL Pension Trustees II Limited and Others (the "Virgin Media Case") related to certain amendments to UK pension plans.

The UK government has introduced legislation to address industry wide issued resulting from the Virgin Media Case.

Such legislation, if adopted, will enable us to proceed with the conversion to a buy-out policy.

In April 2026, the UK government approved legislation to address industry wide issues resulting from the Virgin Media Case.

This legislation will enable us to proceed with the conversion to a buy-out policy.

The following table provides the components of net periodic benefit cost for the pension plans:

Three Months Ended

September 30, Nine Months Ended

September 30,

2025 2024 2025 2024

(Dollars in millions)

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Defined contribution plan expense $ 2.9 $ 3.3

Weighted Average Interest Rate Maturity September 30, 2025 December 31, 2024

Weighted Average Interest Rate Maturity March 31, 2026 December 31, 2025

(Dollars in millions)

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The interest rate on the Credit Facility is variable and may be based on the SOFR, which is the applicable benchmark for current borrowings, or an alternative benchmark depending on the borrowing type.

In June 2025, we amended the Credit Facility to, among other things, (a) extend the maturity date of the Credit Facility to January 9, 2030 at the earliest;

(b) modify the total net leverage ratio financial covenant by making the test 4.75 :1 throughout the life of the Credit Facility;

and (c) modify the interest rate margins applicable to the Credit Facility by removing the 10 basis point credit spread adjustment and increasing the total net leverage ratio test used to determine the applicable interest rate margin.

Borrowings under the Credit Facility are secured by a first priority lien on substantially all of the assets (excluding real property and other customary assets) of Koppers Inc., Koppers Holdings Inc.

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and its restricted subsidiaries to meet certain financial ratios.

As of September 30, 2025, we had $ 341.1 million of unused revolving credit availability after restrictions from certain letter of credit commitments and other covenants.

As of September 30, 2025, $ 7.2 million of commitments were utilized by outstanding letters of credit.

As of March 31, 2026, we had $ 343.5 million of unused revolving credit availability after restrictions from certain letter of credit commitments and other covenants.

As of March 31, 2026, $ 7.2 million of commitments were utilized by outstanding letters of credit.

Term Loan B – In April 2023, we issued a class of senior secured term loans under the Credit Facility (the Term Loan B) which was upsized in April 2024, resulting in $ 488.0 million of aggregate net proceeds, before debt financing costs.

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These costs will likely increase given the remedy has not and will not be implemented for several years.

Responsibility for implementing and funding that work will be decided in the separate private allocation process which is ongoing.

Responsibility for implementing and funding that work will be decided in the separate private allocation process which is ongoing and is expected to provide further clarification with respect to liability allocation in 2026.

In November 2024, Koppers Inc.

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has agreed to resolve its natural resource damage liabilities for the assessment area pursuant to a consent decree lodged with the United States District Court for the District of Oregon in November 2023.

The consent decree has not yet been approved by the court.

The consent decree was approved by the District Court in October 2025, and one party has appealed that decision to the United States Court of Appeals for the Ninth Circuit.

A second matter involves a lawsuit filed in January 2017 by the Yakama Nation in the United States District Court for the District of Oregon.

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is a de minimis party at this site.

We have accrued the estimated costs of participating in the PRP groups at the Portland Harbor and Newark Bay CERCLA sites and estimated de minimis contributor settlement amounts at the sites totaling $ 3.6 million as of September 30, 2025.

The actual cost could be materially higher as there has not been a determination of how those costs will be allocated among the PRPs at the sites.

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There are two plant sites related to the PC business and one plant site related to the Utility and Industrial Products business in our RUPS segment in the United States where we have recorded environmental remediation liabilities for soil and groundwater contamination which occurred prior to our acquisition of the businesses.

As of September 30, 2025, our estimated environmental remediation liability for these acquired sites totals $ 3.6 million.

As of March 31, 2026, our estimated environmental remediation liability for these acquired sites totals $ 3.6 million.

In June 2024, Koppers Inc.

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There is one plant site related to the PC business located in Australia where we have recorded an environmental remediation liability for soil and groundwater contamination which occurred prior to the acquisition of the business.

As of September 30, 2025, our estimated environmental remediation liability for the acquired site totals $ 1.2 million.

As of March 31, 2026, our estimated environmental remediation liability for the acquired site totals $ 1.2 million.

Environmental Reserves Rollforward.

The following table reflects changes in the accrual for environmental remediation.

As of September 30, 2025 and December 31, 2024, $ 1.7 million and $ 2.3 million, respectively, were classified as current liabilities .

September 30, 2025 December 31, 2024

As of March 31, 2026 and December 31, 2025, $ 1.6 million and $ 1.8 million, respectively, were classified as current liabilities .

March 31, 2026 December 31, 2025

(Dollars in millions)

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Cash expenditures ( 0.1 ) ( 0.4 )

Revision of reserves ( 0.1 ) ( 0.3 )

Currency translation 0.0 0.1

Balance at end of period $ 10.0 $ 10.2

Subsequent Events

On May 8, 2026, we announced that we have made a conditional decision to discontinue distillation and chemical manufacturing operations at our facility in Stickney, Illinois, subject to the satisfaction of any bargaining obligations that might exist with the union that represents certain employees at that facility.

The conditional decision, which is pending negotiations and consultation with the union, was driven by challenging market conditions over the past decade, including unit operating costs outpacing our ability to capture higher pricing, reduced raw material supply from North American steel manufacturers and increased capital requirements.

We anticipate winding down the remaining distillation and chemical production activities by December 31, 2026, pending discussions with the union.

We are tentatively targeting fourth quarter 2026 for shifting production to our coal tar distillation facility located in Nyborg, Denmark.

As part of this conditional decision, we continue to evaluate potentially appropriate uses for the Stickney facility following the end of production activities.

We expect this action to result in pre-tax charges to earnings of $ 227 million to $ 262 million through the end of 2029, $ 170 million to $ 195 million of which constitutes non-cash charges and approximately $ 57 million to $ 67 million of which constitutes cash expenditures.

Estimates of the total pre-tax amount for each major type of cost associated with the discontinuation plan are:

(i) retention and severance costs of approximately $ 5 million (including both for salaried and union employees, and pending negotiations and consultation with the union), (ii) accelerated depreciation and asset write-down costs of approximately $ 170 million to $ 195 million, and (iii) plant cleaning, waste disposal and demolition costs of approximately $ 52 million to $ 62 million.

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-Q

Item 1. Financial Statements