Ecovyst Inc.

Ecovyst Inc. ( Ecovyst or the Company ), formerly PQ Group Holdings Inc., was incorporated in Delaware on August 7, 2015. We trace our roots to the late 1800s with our first sulfuric acid plant and the beginning of our oldest customer relationship. Our common stock is listed on the New York Stock Exchange under the stock ticker ECVT . Unless the context otherwise indicates, the terms Ecovyst Inc., we, us, our, or the Company mean Ecovyst Inc. and our subsidiaries. Effective on December 31, 2025, we completed the sale of our Advanced Materials & Catalysts segment, which includes our investment in affiliated companies, Zeolyst International and Zeolyst C.V. (collectively, the Zeolyst Joint Venture ) to Technip Energies N.V. for a purchase price of $556.0 million, subject to certain adjustments set forth in the agreement. We used $465.0 million of the net cash proceeds to partially repay the Senior Secured Term Loan Facility due June 2031. The results of operations, financial condition and cash flows for the Advanced Materials & Catalysts business are presented herein as discontinued operations. Refer to Note 4 to our consolidated financial statements for additional information. Our Company We are a leading integrated provider of virgin and regenerated sulfuric acid products and services. We believe that our business contributes to improving the sustainability of the environment. We are a leader in our business, holding what we estimate to be a number one or number two supply share position for products and services that generated more than 95% of our 2025 sales.