# EDGAR Filing Document

**Accession Number:** 0001708035
**File Stem:** 0001140361-26-014839
**Filing Date:** 2026-4
**Character Count:** 1249
**Document Hash:** f6fef5d2625acbf2421b3dfce2f9e769
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001140361-26-014839.hdr.sgml**: 20260415

**ACCESSION NUMBER**: 0001140361-26-014839

**CONFORMED SUBMISSION TYPE**: ARS

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251231

**FILED AS OF DATE**: 20260415

**DATE AS OF CHANGE**: 20260415

**EFFECTIVENESS DATE**: 20260415

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Ecovyst Inc.
- **CENTRAL INDEX KEY:** 0001708035
- **STANDARD INDUSTRIAL CLASSIFICATION:** CHEMICALS & ALLIED PRODUCTS [2800]
- **ORGANIZATION NAME:** 08 Industrial Applications and Services
- **EIN:** 813406833
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** ARS
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38221
- **FILM NUMBER:** 26864937

**BUSINESS ADDRESS:**
- **STREET 1:** 600 LEE ROAD, SUITE 200
- **CITY:** WAYNE
- **STATE:** PA
- **ZIP:** 19087
- **BUSINESS PHONE:** 484-617-1200

**MAIL ADDRESS:**
- **STREET 1:** 600 LEE ROAD, SUITE 200
- **CITY:** WAYNE
- **STATE:** PA
- **ZIP:** 19087

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** PQ Group Holdings Inc.
- **DATE OF NAME CHANGE:** 20170531

### Attached PDF Documents

**Attachment 1:** `ny20066677x2_ars.pdf`

_No text found in this document._