---
title: cf.tls_client_auth.cert_subject_dn_legacy
description: The Distinguished Name (DN) of the owner (or requester) of the mTLS client certificate in a legacy format.
image: https://developers.cloudflare.com/core-services-preview.png
---

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#  cf.tls\_client\_auth.cert\_subject\_dn\_legacy 

`cf.tls_client_auth.cert_subject_dn_legacy` ` String ` 

The Distinguished Name (DN) of the owner (or requester) of the mTLS client certificate in a legacy format.

This field defaults to `""` if the connection does not use [mTLS authentication](https://developers.cloudflare.com/ssl/client-certificates/enable-mtls/).

Example value:

```
"/C=US/ST=Texas/L=Austin/O=Access/OU=Access Admins/CN=James Royal"
```

Categories: 
* Request
* mTLS

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```