---
title: x500UniqueIdentifier
description: Binary string used to distinguish between objects that reuse the same distinguished name.
component: pingds
version: 8.1
page_id: pingds:schemaref:at-x500UniqueIdentifier
canonical_url: https://docs.pingidentity.com/pingds/8.1/schemaref/at-x500UniqueIdentifier.html
---

# x500UniqueIdentifier

Binary string used to distinguish between objects that reuse the same distinguished name.

|                             |                                                           |
| --------------------------- | --------------------------------------------------------- |
| *OID*                       | 2.5.4.45                                                  |
| *Names*                     | x500UniqueIdentifier                                      |
| *Syntax*                    | [BitString](s-BitString.html)                             |
| *Equality matching rule*    | [bitStringMatch](mr-bitStringMatch.html)                  |
| *Single value*              | false: multiple values allowed                            |
| *User modification allowed* | true                                                      |
| *Usage*                     | userApplications                                          |
| *Origin*                    | [RFC 4519](https://datatracker.ietf.org/doc/html/rfc4519) |
| *Schema file*               | 00-core.ldif                                              |
| *Used by*                   | [inetOrgPerson](oc-inetOrgPerson.html)                    |