Accepted SSL certificates

Google Checkout currently accepts an SSL certificate whose root certificate is from any of the following Certificate Authorities (CA):

AAA Certificate Services - Comodo CA Limited ABA.ECOM Root CA AddTrust Class 1 CA Root AddTrust External CA Root
AddTrust Public Services Root AddTrust Qualified CA America Online Root CA 1 America Online Root CA 2
AOL Time Warner Root CA 1 AOL Time Warner Root CA 2 Autoridad Certificadora de la Asociacion Nacional del Notariado Mexicano, A.C. Autoridad Certificadora del Colegio Nacional de Correduria Publica Mexicana, A.C.
Baltimore CyberTrust Code Signing Root Baltimore CyberTrust Root Belgacom E-Trust Primary CA beTRUSTed Root CA
beTRUSTed Root CA - Baltimore Implementation beTRUSTed Root CA - Entrust Implementation beTRUSTed Root CA - RSA Implementation C&W HKT SecureNet CA Class A
C&W HKT SecureNet CA Class B C&W HKT SecureNet CA Root C&W HKT SecureNet CA SGC Root Certiposte Classe A Personne
Certiposte Serveur Certisign Autoridade Certificadora AC1S Certisign Autoridade Certificadora AC2 Certisign Autoridade Certificadora AC3S
Certisign Autoridade Certificadora AC4 Certplus Class 1 Primary CA Certplus Class 2 Primary CA Certplus Class 3 Primary CA
Certplus Class 3P Primary CA Certplus Class 3TS Primary CA Certum Root CA Comodo AAA Services root
Comodo Secure Services root Comodo Trusted Services root Deutsche Telekom Root CA 1 Deutsche Telekom Root CA 2
DigiCert Assured ID Root CA DigiCert Global Root CA DigiCert High Assurance EV Root CA DigiNotar Root CA
Digital Signature Trust Co. Baltimore EZ by DST Digital Signature Trust Co. DST (ANX Network) CA Digital Signature Trust Co. DST (UPS) Root CA Digital Signature Trust Co. DSTCA E1
Digital Signature Trust Co. DSTCA E2 Digital Signature Trust Co. DST-Entrust GTI CA Digital Signature Trust Co. Global CA 1 Digital Signature Trust Co. Global CA 2
Digital Signature Trust Co. Global CA 3 Digital Signature Trust Co. Global CA 4 Digital Signature Trust Co. National Retail Federation DST (NRF) Root CA Entrust Root Certification Authority
Entrust.net CA (2048) Entrust.net Client CA Entrust.net Secure Server CA Equifax Secure CA
Equifax Secure eBusiness CA-1 Equifax Secure eBusiness CA-2 Equifax Secure Global eBusiness CA-1 EUnet International Root CA
FESTE, Public Notary Certs FESTE, Verified Certs First Data Digital Certificates Inc. CA FNMT Clase 2 CA
GeoTrust Global CA GeoTrust Primary Certification Authority GlobalSign Root CA GlobalSign Root CA - R2
Go Daddy Class 2 CA GTE CyberTrust Global Root GTE CyberTrust Root GTE CyberTrust Root 5
IPS Chained CAs root IPS CLASE1 root IPS CLASE3 root IPS CLASEA1 root
IPS CLASEA3 root IPS Seguridad CA IPS Servidores root IPS Timestamping root
NetLock Expressz Class C Tanusitvanykiado NetLock Kozjegyzoi Class A Tanusitvanykiado NetLock Uzleti Class B Tanusitvanykiado Network Solutions Certificate Authority
PTT Post Root CA QuoVadis Root CA RSA Data Security Secure Server CA RSA Root Certificate 1
RSA Security 1024 v3 RSA Security 2048 v3 Saunalahden Serveri CA Secure Certificate Services - Comodo CA Limited
Secure Global CA Secure Server CA - RSA Data Security, Inc. SecureNet CA Class A SecureNet CA Class B
SecureNet CA Root SecureNet CA SGC Root SecureSign Root CA1 SecureSign Root CA2
SecureSign Root CA3 SecureTrust CA Security Communication Root CA Servicios de Certificacion - A.N.C.
SIA Secure Client CA SIA Secure Server CA Sonera Class 1 Root CA Sonera Class 2 Root CA
Staat der Nederlanden Root CA Starfield Class 2 CA StartCom Certification Authority Swisskey Root CA
Symantec Root CA TC TrustCenter Germany Class 2 CA TC TrustCenter Germany Class 3 CA TC TrustCenter Class 1 CA
TC TrustCenter Class 2 CA TC TrustCenter Class 3 CA TC TrustCenter Class 4 CA TC TrustCenter Time Stamping CA
TDC Internet Root CA TDC OCES Root CA Thawte Personal Basic CA Thawte Personal Freemail CA
Thawte Personal Premium CA Thawte Premium Server CA Thawte Primary Root CA Thawte Server CA
Thawte Time Stamping CA Trusted Certificate Services - Comodo CA Limited TURKTRUST Certificate Services Provider Root 1 TURKTRUST Certificate Services Provider Root 2
UTN - DATACorp SGC UTN-USER First-Network Applications UTN-USERFirst-Client Authentication and Email UTN-USERFirst-Hardware
UTN-USERFirst-Object ValiCert Class 1 VA ValiCert Class 2 Policy VA ValiCert Class 3 Policy VA
Verisign Class 1 Public Primary CA Verisign Class 1 Public Primary CA - G2 VeriSign Class 1 Public Primary CA - G3 Verisign Class 1 Public Primary OCSP Responder
Verisign Class 2 Public Primary CA VeriSign Class 2 Public Primary CA - G2 VeriSign Class 2 Public Primary CA - G3 Verisign Class 2 Public Primary OCSP Responder
Verisign Class 3 Public Primary CA VeriSign Class 3 Public Primary CA - G2 VeriSign Class 3 Public Primary CA - G2 VeriSign Class 3 Public Primary CA - G3
VeriSign Class 3 Public Primary CA - G5 Verisign Class 3 Public Primary OCSP Responder VeriSign Class 4 Public Primary CA - G2 Verisign Class 4 Public Primary CA - G3
Verisign Secure Server OCSP Responder Verisign Time Stamping Authority CA ViaCode CA Data Visa eCommerce Root
Visa International Global Root 2 Xcert EZ by DST XRamp Global Certification Authority

If you're currently developing in the sandbox environment but aren't seeing callbacks to your HTTPS callback URL, you can use HTTP in the callback URL until you begin integrating into production.