Shares of Ecovyst Inc (NYSE: ECVT) plummeted 9.18% in pre-market trading on Tuesday following the release of its third-quarter 2025 earnings report, which revealed mixed results and a lowered sales outlook for the full year.

The specialty chemicals company reported Q3 sales of $204.9 million, falling short of analyst expectations of $219.2 million despite showing a 33% year-over-year increase. While Ecovyst's adjusted earnings per share of $0.19 met consensus estimates, investors appeared to focus on the revenue miss and the company's revised guidance.

Ecovyst lowered its full-year 2025 sales guidance for continuing operations to a range of $700 million to $740 million, down from its previous forecast of $795 million to $835 million. This reduction in outlook likely contributed to the sharp decline in the stock price as investors reassessed their expectations for the company's near-term performance.

Adding to the market's concerns, Ecovyst announced the divestiture of its Advanced Materials & Catalysts segment for $556 million. While the company plans to use a significant portion of the proceeds to reduce its long-term debt, the sale introduces uncertainty about Ecovyst's future growth prospects and business strategy, potentially factoring into the negative investor sentiment reflected in the stock's pre-market drop.