Data as of Nov 7, 2026
51.51.0.0/16
1 residential-proxy exit · 30 daysMicrosoft Corporation · space held by Microsoft Limited
Residential-proxy exits
Proxy exits
1
<0.01% of its addresses · 30 days
Oct 8, 2026 – Nov 6, 2026
Exits seen per day
2 observations
Registrations in this block
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 |
|---|---|---|---|---|---|---|
| 51.51.0.0/16 | 65,536 | MICROSOFT | Microsoft Limited (ORG-MA42-RIPE) · GB | LEGACY | Dec 8, 2022 | abuse@ |
| └ 51.51.0.0/17 | 32,768 | cloud | unknown | LEGACY | Sep 5, 2025 | abuse@ via MICROSOFT |
| └ 51.51.128.0/17 | 32,768 | cloud | unknown | LEGACY | Sep 5, 2025 | abuse@ via MICROSOFT |
A contact marked “via” is the registry's: the record names none of its own, so the registry hands down its parent's.
Network & registry
Origin network
AS8075
US
- Name
- Microsoft Corporation
- Type
- Hosting
- Registered
- Mar 31, 1997
- Domain
- microsoft.com
- Website
- www.microsoft.com
- Industry
- Software Development
- Spamhaus ASN-DROP
- not listed
Routing timeline
Who has announced this prefix
Summary
Routing history
- Pattern
- Stable
- First seen
- Jul 2015
- Current origin since
- Jul 2015 · 11 yr
- Origin networks
- 1
Whois
Registration for this announcement
- Range
- 51.
51. 0. 0/ 16 - Netname
- MICROSOFT
- Registrant
- Microsoft Limited
- Registrant country
- GB
- Organization
- Microsoft Limited (ORG-MA42-RIPE)
- Org country
- GB
- Type
- LEGACY
- Created
- Dec 8, 2022
- Updated
- Dec 8, 2022
- Maintainer
- RIPE-NCC-LEGACY-MNT
- RIR
- RIPE NCC
- Country
- GB
- Delegated
- Sep 1, 1993
- Status
- assigned
Report abuse
Abuse contact
- abuse@
microsoft. com - Name
- Microsoft Abuse Contact
- Handle
- MAC274-RIPE