diff --git a/lib/Productsup/Platform/Process.php b/lib/Productsup/Platform/Process.php
index 5ed797e..ba920a2 100644
--- a/lib/Productsup/Platform/Process.php
+++ b/lib/Productsup/Platform/Process.php
@@ -14,6 +14,7 @@ class Process extends DataModel {
      * adds a reference to a site that can later be used as an identifier
      * note: this is only possible when creating a site or project
      * @param Reference $reference
+     * @throws ClientException When adding non site reference
      */
     public function addReference(Reference $reference) {
         if ($reference->getKey() != Reference::REFERENCE_SITE) {
@@ -26,13 +27,19 @@ public function addReference(Reference $reference) {
 
     /**
      * cast data to an array
+     * @param boolean $full
      * @return array
      */
-    public function toArray() {
-        return array(
+    public function toArray($full = true) {
+        $data = array(
             'id' => $this->action_id,
             'action' => $this->action,
-            'site_id' => $this->site_id,
         );
+
+        if ($full) {
+            $data['site_id'] = $this->site_id;
+        }
+
+        return $data;
     }
 }
diff --git a/lib/Productsup/Service/Process.php b/lib/Productsup/Service/Process.php
index 297b8a7..438c4e2 100644
--- a/lib/Productsup/Service/Process.php
+++ b/lib/Productsup/Service/Process.php
@@ -45,7 +45,7 @@ public function post(ProcessModel $model) {
 
         $request = $this->getRequest();
         $request->method = Request::METHOD_POST;
-        $request->postBody = $model->toArray();
+        $request->postBody = $model->toArray(false);
         $request->url .= '/'.$model->site_id;
         $data = $this->executeRequest($request);