Sectigo SSL Certificate Authority

Sectigo (formerly Comodo CA) is one of the highest-volume Certificate Authorities in the world, issuing millions of DV, OV, and EV certificates annually. The Comodo CA business was rebranded to Sectigo in 2018. Certificates issued under the Comodo CA brand before the rebrand are still valid and will show O: COMODO CA Limited in the issuer.

Sectigo's Position in the Market

Sectigo is known for aggressive pricing, making it popular with resellers and hosting providers. Many shared hosting providers and domain registrars resell Sectigo certificates under their own brands, so you may see Sectigo's infrastructure (OCSP URLs, CRL endpoints) behind certificates sold by other companies.

Identifying Sectigo Certificates

Current Sectigo certificates show O: Sectigo Limited in the issuer. Older Comodo certificates show O: COMODO CA Limited or O: COMODO RSA Certificate Authority. The OCSP responder URL in the Authority Info Access extension points to http://ocsp.sectigo.com or http://ocsp.comodoca.com.

Common Sectigo Intermediate CAs

Sectigo uses several intermediate CAs depending on the product and key type:

• Sectigo RSA Domain Validation Secure Server CA — DV certificates
• Sectigo RSA Organization Validation Secure Server CA — OV certificates
• Sectigo ECC Domain Validation Secure Server CA — DV certificates with ECDSA keys

When decoding a certificate chain, you'll see one of these as the intermediate issuer between the leaf cert and the Sectigo root.