X0508 4 2025-12-23 0001936258 NewAmsterdam Pharma Co N.V. NAMS 0002004379 Kooij Louise Frederika C/O NEWAMSTERDAM PHARMA COMPANY N.V. GOOIMEER 2-35 NAARDEN P7 1411 DC NETHERLANDS false true false false Chief Accounting Officer true Ordinary Shares 2025-12-23 4 M false 75117 10.00 A 90117 D Ordinary Shares 2025-12-23 4 S false 75117 36.21 D 15000 D Ordinary Shares 2025-12-24 4 M false 26011 10.00 A 41011 D Ordinary Shares 2025-12-24 4 S false 26011 35.68 D 15000 D Ordinary Shares 2025-12-26 4 M false 38872 10.00 A 53872 D Ordinary Shares 2025-12-26 4 M false 5000 10.90 A 58872 D Ordinary Shares 2025-12-26 4 S false 43872 35.30 D 15000 D Option (right to buy) 10.00 2025-12-23 4 M false 75117 0.00 D 2032-11-22 Ordinary Shares 75117 204898 D Option (right to buy) 10.00 2025-12-24 4 M false 26011 0.00 D 2032-11-22 Ordinary Shares 26011 178887 D Option (right to buy) 10.00 2025-12-26 4 M false 38872 0.00 D 2032-11-22 Ordinary Shares 38872 140015 D Option (right to buy) 10.90 2025-12-26 4 M false 5000 0 D 2033-01-01 Ordinary Shares 5000 218134 D The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $35.88 to $36.75 per share. 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 in each transaction. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $35.24 to $36.09 per share. 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 in each transaction. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $34.85 to $35.56 per share. 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 in each transaction. The option was granted on November 22, 2022. The shares underlying the option vest in equal monthly installments over four years, with the first 1/48th of such shares vesting on December 1, 2022 and the remaining installments vesting on each one-month anniversary of the grant date, subject to the Reporting Person's continued service through each such date. The option was granted on January 1, 2023. 25% of the shares underlying the option vest on the one-year anniversary of vesting start date, with the remaining shares vesting in equal monthly installments thereafter for three years, subject to the Reporting Person's continued service through each such date. /s/ Louise Kooij 2025-12-29