diff --git a/src/rspro_util.c b/src/rspro_util.c
index 95e8cfc..0452728 100644
--- a/src/rspro_util.c
+++ b/src/rspro_util.c
@@ -118,7 +118,8 @@
 		return NULL;
 	pdu->msg.present = RsproPDUchoice_PR_connectClientReq;
 	fill_comp_id(&pdu->msg.choice.connectClientReq.identity, a_cid);
-	ASN_ALLOC_COPY(pdu->msg.choice.connectClientReq.clientSlot, client);
+	if (client)
+		ASN_ALLOC_COPY(pdu->msg.choice.connectClientReq.clientSlot, client);
 
 	return pdu;
 }