diff --git a/library/ecp.c b/library/ecp.c
index 351e9e8..b4da3c5 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -3371,15 +3371,15 @@
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
-    if ((ret = mbedtls_ecp_group_copy(grp, &key->grp)) != 0) {
+    if (grp != NULL && (ret = mbedtls_ecp_group_copy(grp, &key->grp)) != 0) {
         return ret;
     }
 
-    if ((ret = mbedtls_mpi_copy(d, &key->d)) != 0) {
+    if (d != NULL && (ret = mbedtls_mpi_copy(d, &key->d)) != 0) {
         return ret;
     }
 
-    if ((ret = mbedtls_ecp_copy(Q, &key->Q)) != 0) {
+    if (Q != NULL && (ret = mbedtls_ecp_copy(Q, &key->Q)) != 0) {
         return ret;
     }