Koppers Holdings Inc

ITEM 1A. RISK FACTORS

There have been no material changes to the Risk Factors previously disclosed in Item 1A of oPart I of our Annual Report on Form 10-K for the year ended December 31, 2024, except for the addition of the following risk factors.

Changes to United States tariffs, import and export regulations and potential countermeasures could increase our costs and disrupt our global supply chain, which could negatively impact our business, results of operations and cash flows.

On an annual basis, we import approximately $100 million to $120 million of products into the United States, including sales from affiliates which are eliminated in consolidation. These imports are principally raw materials for our PC and CMC businesses. The majority of our imports are from countries other than China. We export approximately $90 million to $110 million of products from the United States to other countries, including sales to affiliates which are eliminated in consolidation.

Significant uncertainty exists around the future relationship between the United States and other countries with respect to tariffs and other trade matters. The United States has recently instituted or proposed changes in trade policies that include the renegotiation or termination of trade agreements, the imposition of higher tariffs on imports into the United States, economic sanctions on individuals, corporations or countries, and other government regulations affecting trade between the United States and other countries. In response to these actions, other countries have announced retaliatory tariffs and other trade measures against the United States. We have estimated the effect of the increased tariffs, as they currently stand, could have a $54 million to $98 million impact on our pre-tax profit during 2025 if we are unable to mitigate them, which we intend to do. Mitigation efforts include changing the origin of sourcing materials, sharing of incremental tariff costs with vendors and customer price increases where contractually possible.

These developments, or the perception that any of them could occur, may have a material adverse effect on global economic conditions and the stability of global financial markets, and may significantly reduce global trade between the impacted countries and the United States. This could impact the way we do business and could increase the cost of our products in certain contracts that do not allow for price increases related to these types of costs. In addition, the potential for the imposition of new or additional tariffs on imports and exports as well as potential retaliatory tariffs or other measures certain other countries may impose on the United States could further increase our cost of goods sold and negatively impact our business, results of operations, liquidity and cash flows. Supply chain disruptions, increased volatility in the markets in which we operate, and delays as a result of any new tariff policies or trade restrictions could have a material adverse effect on our financial condition, results of operations, liquidity and cash flows.

Our hedging activities to address commodity price fluctuations may not be successful in offsetting future increases in those costs.

In order to mitigate variations in operating results due to the commodity price fluctuations, we hedge the majority of our exposure to scrap copper and copper-containing raw materials used in our production processes. The results of this hedging practice could be positive, neutral or negative in any period depending on price changes in the hedged

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exposures and the correlation of the price changes in the financial instruments we use to hedge. Our hedging instruments primarily utilize the London Metal Exchange (LME) index while the majority of our purchases are priced off of the Commodity Exchange, Inc. (COMEX) index. Historically, price changes in the LME and the COMEX have been highly correlated and our hedges have been effective in mitigating our financial exposure to changes in the price of copper.

In July 2025, the U.S Depart. government of Commimposed 50 perce initiated a Sectint tariffs on 232 investigation to determine the effeimports of semi-finished copper products on national security of imports of copper in all formsand copper-intensive derivative products, effective August 1, 2025. As a result of potential and anctual or anticipated U.S., tariffs being levied on the importation of copper at the conclusion ofhave caused and can continue to cause significant premiums to the investigation, COMEX prices are trading at a five to 20 percent premium cs compared to LME prices as of Mar. Such 31, 2025. As apremiums can result,  in our hedging instruments arebeing less effective in offsetting increases in raw material prices when such a premium exists. Sustained and prolonged premiums of COMEX pricing over LME pricing could have a material adverse effect on our financial condition, results of operations, liquidity and cash flows.

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