X0206 3 2022-02-28 0 0000310158 Merck & Co., Inc. MRK 0001916360 Garay Arpa MERCK & CO., INC. 2000 GALLOPING HILL ROAD KENILWORTH NJ 07033 1 SVP Human Health Global Mktg. Common Stock 290 D Restricted Stock Unit 2020-05-03 2022-05-03 Common Stock 773 D Restricted Stock Unit 2021-05-01 2023-05-01 Common Stock 1732 D Restricted Stock Unit 2021-10-30 2023-10-30 Common Stock 1828 D Restricted Stock Unit 2022-05-04 2024-05-04 Common Stock 2726 D Restricted Stock Unit 2022-08-03 2024-08-03 Common Stock 13087 D Stock Option (Right to Buy) 77.62 2020-05-03 2029-05-02 Common Stock 5821 D Stock Option (Right to Buy) 75.36 2021-05-01 2030-04-30 Common Stock 13543 D Stock Option (Right to Buy) 73.73 2022-05-04 2031-05-03 Common Stock 21139 D The restricted stock units vest and are distributed as shares of Merck & Co., Inc. common stock in three equal installment on 5/3/2020, 5/3/2021 and 5/3/2022. Each restricted stock unit represents a contingent right to receive one share of Merck & Co., Inc. common stock. These restricted stock units vest and are distributed as shares of Merck & Co., Inc. common stock in three equal installments on 5/1/2021, 5/1/2022 and 5/1/2023. These restricted stock units vest and are distributed as shares of Merck & Co., Inc. common stock in three equal installments on 10/30/2021, 10/30/2022 and 10/30/2023. These restricted stock units vest and are distributed as shares of Merck & Co., Inc. common stock in three equal installments on 5/4/2022, 5/4/2023 and 5/4/2024. These restricted stock units vest and are distributed as shares of Merck & Co., Inc. common stock in three equal installments on 8/3/2022, 8/3/2023 and 8/3/2024. The options become exercisable in three equal installments on 5/3/2020, 5/3/2021 and 5/3/2022. The options become exercisable in three equal installments on 5/1/2021, 5/1/2022 and 5/1/2023. The options become exercisable in three equal installments on 5/4/2022, 5/4/2023 and 5/4/2024. See Exhibit 24 - Power of Attorney /s/ Kelly E. W. Grez, as attorney-in-fact for Arpa Garay 2022-03-10