X0508 4 2024-08-07 0001122976 AVIENT CORP AVNT 0001661555 Rathbun Joel R. AVIENT CORPORATION 33587 WALKER ROAD AVON LAKE OH 44012 1 SVP, Mergers & Acquisitions 0 Common Stock 2024-08-07 4 M 0 2500 38.27 A 10840 D Common Stock 2024-08-07 4 D 0 2285 43.58 D 8555 D Common Stock 2024-08-07 4 M 0 10400 24.98 A 18955 D Common Stock 2024-08-07 4 D 0 7257 43.66 D 11698 D Common Stock 2024-08-07 4 S 0 11698 43.3594 D 0 D Common Stock 28416.08 I Supplemental Plan Stock Appreciation Rights 38.27 2024-08-07 4 M 0 2500 0 D 2025-02-04 Common Stock 2500 0 D Stock Appreciation Rights 24.98 2024-08-07 4 M 0 10400 0 D 2026-02-10 Common Stock 10400 0 D The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $43.21 to $43.54, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within this range. The information in this report is based on a plan statement as of August 7, 2024. SARs become exercisable and vest only upon the achievement of both price and time requirements. To vest, each one-third of the grant must attain 10%, 15% and 20% stock appreciation, respectively (which must be maintained for a minimum of thirty consecutive trading days) from the grant date closing price of $38.27 per share and no more than one-third of the grant can vest per year during the first three years. SARs become exercisable and vest only upon the achievement of both price and time requirements. To vest, each one-third of the grant must attain 10%, 15% and 20% stock appreciation, respectively (which must be maintained for a minimum of thirty consecutive trading days) from the grant date closing price of $24.98 per share and no more than one-third of the grant can vest per year during the first three years. /s/ Robert K. James, Power of Attorney For: Joel R. Rathbun 2024-08-09