# Certificate Transparency + X.509v3 Extension

**URL:** <https://community.letsencrypt.org/t/certificate-transparency-x-509v3-extension/7186>\
**Category:** Feature Requests\
**Created:** [December 16, 2015, 2:42pm UTC](https://community.letsencrypt.org/t/certificate-transparency-x-509v3-extension/7186 "2015-12-16T14:42:24Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![tlussnig](https://sea3.discourse-cdn.com/letsencrypt/user_avatar/community.letsencrypt.org/tlussnig/32/2053_2.png) [@tlussnig](https://community.letsencrypt.org/u/tlussnig)\
**Post date:** [December 16, 2015, 2:42pm UTC](https://community.letsencrypt.org/t/certificate-transparency-x-509v3-extension/7186/1 "2015-12-16T14:42:24Z")

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Hi is there an plan to support CT via X509.3 extensions in the certificate?  
So that there is no need to modify the server, i think this will make it easyer  
for the users.

> **[How CT Works : Certificate Transparency](https://certificate.transparency.dev/howctworks/)**
>
> Certificate Transparency

> X.509v3 ExtensionCertificate  
> authorities can attach an SCT to a certificate using an X.509v3  
> extension. Figure 1 shows how this works. The certificate authority (CA)  
> submits a precertificate to the log, and the log returns an SCT. The CA  
> then attaches the SCT to the precertificate as an X.509v3 extension,  
> signs the certificate, and delivers the certificate to the server  
> operator.

> This  
> method does not require any server modification, and it lets server  
> operators continue to manage their SSL certificates the same way they  
> always have

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**Author:** ![selecadm](https://sea3.discourse-cdn.com/letsencrypt/user_avatar/community.letsencrypt.org/selecadm/32/5114_2.png) [@selecadm](https://community.letsencrypt.org/u/selecadm)\
**Post date:** [December 16, 2015, 2:44pm UTC](https://community.letsencrypt.org/t/certificate-transparency-x-509v3-extension/7186/2 "2015-12-16T14:44:46Z")

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By @jsha

> If we provide SCTs, it would be via OCSP, definitely not by X.509v3 extension.

> [@Will you support Certificate Transparency?](https://community.letsencrypt.org/t/will-you-support-certificate-transparency/222):
>
> W…

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**Author:** ![tlussnig](https://sea3.discourse-cdn.com/letsencrypt/user_avatar/community.letsencrypt.org/tlussnig/32/2053_2.png) [@tlussnig](https://community.letsencrypt.org/u/tlussnig)\
**Post date:** [December 16, 2015, 2:49pm UTC](https://community.letsencrypt.org/t/certificate-transparency-x-509v3-extension/7186/3 "2015-12-16T14:49:11Z")

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Sorry my fault ☹ Did not look properly.