diff --git a/lib/setopt.c b/lib/setopt.c
index 57e1090ce..5f88ad3af 100644
--- a/lib/setopt.c
+++ b/lib/setopt.c
@@ -2142,6 +2142,7 @@ CURLcode Curl_vsetopt(struct Curl_easy *data, CURLoption option, va_list param)
     data->set.proxy_ssl.enable_beast =
       (bool)((arg&CURLSSLOPT_ALLOW_BEAST) ? TRUE : FALSE);
     data->set.proxy_ssl.no_revoke = !!(arg & CURLSSLOPT_NO_REVOKE);
+    data->set.proxy_ssl.no_partialchain = !!(arg & CURLSSLOPT_NO_PARTIALCHAIN);
     break;
 #endif
 
diff --git a/packages/OS400/curl.inc.in b/packages/OS400/curl.inc.in
index 9a44eae49..3f32b358d 100644
--- a/packages/OS400/curl.inc.in
+++ b/packages/OS400/curl.inc.in
@@ -760,6 +760,8 @@
      d                 c                   X'0001'
      d CURLSSLOPT_NO_REVOKE...
      d                 c                   X'0002'
+     d CURLSSLOPT_NO_PARTIALCHAIN...
+     d                 c                   X'0004'
       *
      d CURL_HET_DEFAULT...
      d                 c                   200
diff --git a/src/tool_setopt.c b/src/tool_setopt.c
index e56af1317..9b308bf4a 100644
--- a/src/tool_setopt.c
+++ b/src/tool_setopt.c
@@ -124,6 +124,7 @@ const NameValue setopt_nv_CURLUSESSL[] = {
 const NameValueUnsigned setopt_nv_CURLSSLOPT[] = {
   NV(CURLSSLOPT_ALLOW_BEAST),
   NV(CURLSSLOPT_NO_REVOKE),
+  NV(CURLSSLOPT_NO_PARTIALCHAIN),
   NVEND,
 };