diff --git a/docs/x509.rst b/docs/x509.rst
index 932801b..ade8076 100644
--- a/docs/x509.rst
+++ b/docs/x509.rst
@@ -663,14 +663,21 @@
 
         :type: bytes
 
+        A value derived from the public key used to verify the certificate's
+        signature.
+
     .. attribute:: authority_cert_issuer
 
         :type: :class:`Name` or None
 
+        The :class:`Name` of the issuer's issuer.
+
     .. attribute:: authority_cert_serial_number
 
         :type: int or None
 
+        The serial number of the issuer's issuer.
+
 .. class:: SubjectKeyIdentifier
 
     .. versionadded:: 0.9