205.138.0.0/15

Currently announced by AS3561 Lumen AS3561, in the routed prefix 205.138.0.0/15.

Current ASN: AS3561; Lumen AS3561
Routed prefix: 205.138.0.0/15; Most specific route covering this prefix
ASNs over time: 1; 1 announcement record
RIR allocation: ARIN; United States · 205.138.0.0/15

Routing data · Nov 8, 2026, 10:26 UTC

ASN historyEvery routed prefix covering 205.138.0.0/15

Prefix	ASN	Name	Registered country	First seen (UTC)	Last seen (UTC)	Status
205.138.0.0/15	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing

More specific routes38 total

Prefix	ASN	Name	Registered country	First seen (UTC)	Last seen (UTC)	Status
205.138.24.0/21	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.32.0/21	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.40.0/21	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.112.0/22	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.116.0/22	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.120.0/21	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.144.0/20	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.168.0/22	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.172.0/22	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.224.0/20	AS209	Lumen AS209	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.240.0/20	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.242.0/24	AS13458	DAVIDSON KEMPNER CAPITAL MANAGEMENT LP	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.243.0/24	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.247.0/24	AS396167	Blackhawk Network, Inc.	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.249.0/24	AS10753	Level 3 Parent, LLC	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.16.0/20	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.21.0/24	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.32.0/19	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.64.0/20	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.68.0/24	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.88.0/23	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.96.0/20	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.102.0/24	AS203	Level 3 Parent, LLC	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.103.0/24	AS203	Level 3 Parent, LLC	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.104.0/22	AS203	Level 3 Parent, LLC	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.108.0/24	AS203	Level 3 Parent, LLC	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.110.0/24	AS30031	Mimecast North America Inc	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.111.0/24	AS30031	Mimecast North America Inc	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.112.0/20	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.128.0/19	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.132.0/24	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.142.0/24	AS22013	Guardian Analytics, Inc.	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.144.0/22	AS19701	Yodlee Inc.	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.154.0/24	AS22013	Guardian Analytics, Inc.	United States	Before monitoring	2026-11-08 10:26	Announcing
205.139.160.0/20	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-08 10:26	Announcing
205.138.192.0/22	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-06 08:25	Stopped
205.138.196.0/24	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-06 08:25	Stopped
205.138.197.0/24	AS3561	Lumen AS3561	United States	Before monitoring	2026-11-06 08:25	Stopped

Change logAll changes

The routes covering this address have had no origin changes since ASNBase started monitoring.

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RIR allocation record

Registry: ARIN
Allocated block: 205.138.0.0/15
Country: United States
Allocation date: 1995-02-15
Status: allocated

From the RIRs’ delegated statistics files. Shows where the addresses are registered, not where they are used.

How monitoring works

Every 2 hours ASNBase takes the bgp.tools global routing table (prefix → origin ASN) and compares it with the previous one. The detected time is the time of that comparison; the actual change can be up to about 2 hours earlier.
Only routes seen by more than 100 bgp.tools peers are listed as changes; routes with less visibility are only kept in the history.
A new announcement counts only if it is still in the next routing table, and a withdrawal only if the prefix is missing from two tables in a row, so short flaps are ignored.
ASNBase has been monitoring since 2026-10-19. “Before monitoring” under “First seen” means the route was already announced when monitoring started; the earlier date is unknown.
Prefixes first seen during the first day of monitoring do not count as new announcements: most of them were simply missing from the table at the moment monitoring started.
Countries and regions follow the ASN’s registration, not the actual location of the IP addresses.