+=item B<-receipt_request_all -receipt_request_first>
+
+for B<-sign> option include a signed receipt request. Indicate requests should
+be provided by all receipient or first tier recipients (those mailed directly
+and not from a mailing list). Ignored it B<-receipt_request_from> is included.
+
+=item B<-receipt_request_from emailaddress>
+
+for B<-sign> option include a signed receipt request. Add an explicit email
+address where receipts should be supplied.
+
+=item B<-receipt_request_to emailaddress>
+
+Add an explicit email address where signed receipts should be sent to. This
+option B<must> but supplied if a signed receipt it requested.
+
+=item B<-receipt_request_print>
+
+For the B<-verify> operation print out the contents of any signed receipt
+requests.
+