| Property | Value |
| NameServer | NS4.HMCO.COM |
| Created | 1999-02-17 00:00:00 |
| Changed | 2015-04-23 00:00:00 |
| Expires | 2021-01-05 00:00:00 |
| Registrar | NETWORK SOLUTIONS, L |
| Date | IP Address |
| 2023-09-03 | 3.90.96.235 (ClassC) |
| 2025-04-30 | 34.198.37.118 (ClassC) |
| 2025-06-22 | 54.166.126.155 (ClassC) |
| 2025-07-22 | 34.202.106.108 (ClassC) |
| 2025-08-11 | 34.237.168.187 (ClassC) |
| 2025-09-19 | 3.230.229.192 (ClassC) |
| Date | Domain | IP |
| customerservice.harcourt.com | 2024-11-24 | 18.210.132.154 |
| research.harcourt.com | 2025-04-30 | 34.198.37.118 |
| customerservice-t.harcourt.com | 2025-05-14 | 44.207.34.36 |
| support.harcourt.com | 2025-02-19 | 100.27.74.206 |
| www.harcourt.com | 2025-09-06 | 209.235.125.223 |