title: Why is it that bouncycastle needs the issuer certificate in order to check the OCSP status of a given certificate?
body: <p>Please excuse my ignorance, but I'm slowly making my way through the depts of using bouncycastle and cryptography at all.</p>
  
  <p>I'm experimenting with OCSP and I'm trying to check the revocation status of a certificate using bouncycastle.
  I dont understand why does bouncycastle need the issuer certificate in order to do that? To build a OCSPReq I have to provide a CertificateID object which needs the issuer cert.
  What is the point? In my understanding all I need for an OCSP check is the certificate I'm checking and the URI of the OCSP responder... Please correct me if I'm wrong.</p>
  
  <p>Thanks!</p>