Data as of Nov 5, 2026

156.40.0.0/16

No anonymizer space · no proxy exits in 30 days

National Institutes of Health

Announcement

this exact prefix

No RPKI

Announced by

Type

Business

Announcements

More specific

Prefix	Origin	Type	Holder
156.40.53.0/24 since Aug 2015	AS30387	Business	National Institutes of Health
156.40.93.0/24 since May 2015	AS19050	Business	U.S. Department of Health & Human Services
156.40.94.0/24 since Jul 2015	AS19050	Business	U.S. Department of Health & Human Services
156.40.95.0/24 since Jun 2017	AS19050	Business	U.S. Department of Health & Human Services
156.40.98.0/23 since May 2015	AS30387	Business	National Institutes of Health
156.40.197.0/24 since May 2015	AS19050	Business	U.S. Department of Health & Human Services
156.40.246.0/24 since Jul 2026	AS19050	Business	National Institutes of Health

The registry's network records over the announcement: those covering it, widest first, then every record inside it, under its parent.

Range	Addresses	Netname	Holder	Type	Created	Abuse contact
156.40.0.0 - 156.40.92.255	23,808	NIHNET-3	National Institutes of Health (NIH-Z) · US	Direct Allocation	Dec 9, 1991	citnsarin@mail.nih.gov
156.40.93.0 - 156.40.95.255	768	UDHHS-4	U.S. Department of Health & Human Services (UDHHS-4) · US	Direct Allocation	Dec 9, 1991	citnsarin@mail.nih.gov
156.40.96.0 - 156.40.196.255	25,856	NIHNET-3	National Institutes of Health (NIH-Z) · US	Direct Allocation	Dec 9, 1991	citnsarin@mail.nih.gov
156.40.197.0/24	256	UDHHS-4	U.S. Department of Health & Human Services (UDHHS-4) · US	Direct Allocation	Dec 9, 1991	citnsarin@mail.nih.gov
156.40.198.0 - 156.40.255.255	14,848	NIHNET-3	National Institutes of Health (NIH-Z) · US	Direct Allocation	Dec 9, 1991	citnsarin@mail.nih.gov
└ 156.40.246.0/24	256	UDHHS-4	U.S. Department of Health & Human Services (C11646617) · US	Reassigned	Jul 10, 2026	citnsarin@mail.nih.gov via NIHNET-3

A contact marked “via” is the registry's: the record names none of its own, so the registry hands down its parent's.

Registry

Origin network

Name: National Institutes of Health
Type: Business
Registered: Apr 7, 1994
Domain: nih.gov
Industry: Government and Regulatory Agencies, Administrations, Departments, and Services
Spamhaus ASN-DROP: not listed

IRR

Origin	Registry	Description	Maintainer	Modified
AS3527	RADB	Proxy-registered route object for NIH	MAINT-AS10886	Nov 13, 2023

IRR inside

Prefix	Origin	Registry	Description	Maintainer	Modified
156.40.0.0/18	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.64.0/20	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.80.0/21	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.88.0/22	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.92.0/24	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.94.0/23	AS19050	ARIN	U.S. Department of Health & Human Services	MNT-UDHHS-4	May 9, 2025
156.40.96.0/19	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.116.0/22	AS3527	RADB	Proxy-registered route object for NIH	MAINT-AS10886	Nov 13, 2023
156.40.120.0/22	AS3527	RADB	Proxy-registered route object for NIH	MAINT-AS10886	Nov 13, 2023
156.40.128.0/18	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.192.0/22	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.196.0/24	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.198.0/23	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.200.0/21	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.208.0/20	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.224.0/19	AS3527	ARIN	9000 Rockville Pike	MNT-NIH-Z	Jun 5, 2025
156.40.254.0/23	AS3527	RADB	Proxy-registered route object for NIH	MAINT-AS10886	Nov 13, 2023
156.40.254.0/24	AS3527	RADB	Proxy-registered route object for NIH	MAINT-AS10886	Nov 13, 2023
156.40.255.0/24	AS3527	RADB	Proxy-registered route object for NIH	MAINT-AS10886	Nov 13, 2023