Data as of Nov 12, 2026

51.53.0.0/16

No anonymizer space · no proxy exits in 30 days

Microsoft Corporation · space held by Microsoft Limited

Announcement
this exact prefix
RPKI valid
Announced by
Type
Hosting
Risk
50 / 100 · Medium

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.

RangeAddressesNetnameHolderTypeCreatedAbuse contact
51.53.0.0/1665,536MICROSOFTMicrosoft Limited (ORG-MA42-RIPE) · GBLEGACYMay 21, 2015abuse@microsoft.com
└ 51.53.0.0/1732,768cloudunknownLEGACYSep 5, 2025abuse@microsoft.com
via MICROSOFT
└ 51.53.128.0/1732,768cloudunknownLEGACYSep 5, 2025abuse@microsoft.com
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

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