| Date | IP Address |
| 2021-05-31 | 104.78.245.244 (ClassC) |
| 2023-08-25 | 104.86.253.113 (ClassC) |
| 2024-03-12 | 23.223.223.111 (ClassC) |
| 2024-04-04 | 23.56.191.63 (ClassC) |
| 2024-07-07 | 104.92.255.59 (ClassC) |
| 2024-07-16 | 23.37.208.106 (ClassC) |
| 2025-01-23 | 23.59.88.196 (ClassC) |
| 2025-04-11 | 23.38.191.163 (ClassC) |
| 2025-08-13 | 23.41.4.81 (ClassC) |
| 2025-09-06 | 23.41.4.87 (ClassC) |
| 2025-09-20 | 23.46.17.183 (ClassC) |
| 2025-09-29 | 23.46.17.171 (ClassC) |
| 2025-10-16 | 23.44.229.163 (ClassC) |
| Date | Domain | IP |
| la1.www4.irs.gov | 2023-08-25 | 104.86.253.111 |
| sa1.www4.irs.gov | 2023-08-25 | 104.86.253.151 |
| la2.www4.irs.gov | 2023-08-25 | 104.86.253.111 |
| sa2.www4.irs.gov | 2023-08-25 | 104.86.253.151 |
| la3.www4.irs.gov | 2023-08-25 | 104.86.245.147 |
| sa3.www4.irs.gov | 2023-08-25 | 104.86.245.147 |
| la4.www4.irs.gov | 2023-08-25 | 104.86.245.147 |
| sa4.www4.irs.gov | 2023-08-25 | 104.86.245.147 |
| la.www4.irs.gov | 2023-08-25 | 104.86.253.111 |