X0306 4/A 2022-02-16 2022-02-17 0 0001333274 MERCER INTERNATIONAL INC. MERC 0001378338 Ure David Kent SUITE 1120 700 WEST PENDER STREET VANCOUVER A1 V6C 1G8 BRITISH COLUMBIA, CANADA 0 1 0 0 Senior Vice President, Finance Common Stock 2022-02-16 4 M 0 5371 0 A 68921 D Common Stock 2022-02-16 4 F 0 2686 12.875 D 66235 D Performance Share Units 0 2022-02-16 4 A 0 5371 0 A Common Stock 5371 5371 D Performance Share Units 0 2022-02-16 4 M 0 5371 0 A Common Stock 5371 0 D Represents the conversion of vested performance share units ("PSUs"). Represents the average of the intraday high and low trading price on February 16, 2022. Represents the vesting on February 16, 2022 of PSUs awarded to the reporting person based on the achievement of certain specified performance criteria, including company performance and share price performance during the 2019 to 2021 performance period. REMARKS This amendment to the Form 4 originally filed on February 17, 2022 is being filed solely to correct a transposition of digits/typographical error in the number of Securities disposed of and is not the result of a new transaction. No other information is being amended. /s/David Ure 2022-03-10