X0508 4 2025-11-03 0 0001084991 NATURAL GAS SERVICES GROUP INC NGS 0001629779 Tucker Brian L 1250 NE LOOP 410 #1000 SAN ANTONIO TX 78209 0 1 0 0 President & COO 0 Common Stock 2025-11-03 4 A 0 128 A 5327 D Common Stock 2025-11-03 4 A 0 2486 A 7813 D Common Stock 2025-11-03 4 A 0 1909 A 9722 D Common Stock 2025-11-03 4 A 0 6250 A 15972 D Common Stock 2025-11-03 4 A 0 1910 A 17882 D Common Stock 2025-11-03 4 F 0 3849 27.84 D 14033 D Restricted Stock Units 2025-11-03 4 M 0 128 0 A Common Stock 128 0 D Restricted Stock Units 2025-11-03 4 M 0 2486 0 A Common Stock 2486 0 D Restricted Stock Units 2025-11-03 4 M 0 1909 0 A Common Stock 1909 0 D Not applicable. Represents shares acquired in connection with the vesting of a Restricted Stock Unit ("RSU") award. Not applicable. Represents shares acquired in connection with the vesting of A Performance Share Award ("PSU"). Not applicable. Each RSU and/or PSU represents the right to receive one share of the Company's common stock upon vesting without payment. A total of 1,992 RSUs from the 2023 RSU Grant were forfeited in connection with the reporting person's retirement. A total of 5,043 RSUs from the 2024 RSU Grant were forfeited in connection with the reporting person's retirement. A total of 7,105 RSUs from the 2025 RSU Grant were forfeited in connection with the reporting person's retirement. Brian L. Tucker 2025-11-03