| Property | Value |
| Name | Houghton Mifflin Harcourt |
| Organization | Houghton Mifflin Harcourt |
| nameserv@hmhco.com | |
| Address | 222 Berkeley St. |
| Zip Code | 02116 |
| City | Boston |
| State | MA |
| Country | US |
| Phone | +1.6173515000 |
| NameServer | NS6.HMCO.COM |
| Created | 2002-10-17 04:00:00 |
| Changed | 2015-06-08 13:31:24 |
| Expires | 2021-10-17 00:00:00 |
| Registrar | NETWORK SOLUTIONS, L |
| Date | IP Address |
| 2023-09-03 | 3.90.96.235 (ClassC) |
| 2025-05-11 | 3.214.241.145 (ClassC) |
| 2025-06-05 | 54.90.225.137 (ClassC) |
| 2025-07-08 | 52.21.243.5 (ClassC) |
| 2025-07-31 | 34.198.171.34 (ClassC) |
| 2025-08-22 | 54.159.176.151 (ClassC) |
| 2025-09-01 | 23.23.2.51 (ClassC) |
| 2025-09-26 | 52.206.139.23 (ClassC) |
| 2026-01-02 | 34.226.49.69 (ClassC) |
| Date | Domain | IP |
| www-k6.thinkcentral.com | 2025-11-09 | 45.60.11.203 |
| help.thinkcentral.com | 2025-05-11 | 3.214.241.145 |
| importhelp.thinkcentral.com | 2024-11-24 | 18.210.132.154 |
| ssms.thinkcentral.com | 2025-09-01 | 45.60.11.203 |
| ssms-cert.thinkcentral.com | 2025-09-01 | 45.60.11.203 |
| www-cert.thinkcentral.com | 2025-09-08 | 45.60.11.203 |
| www.thinkcentral.com | 2025-08-19 | 45.60.11.203 |