diff --git a/src/HAB/Solr/Command/Invoker.php b/src/HAB/Solr/Command/Invoker.php
index 2ee57757a2113f7633e4ddd89037cdfadf270441..bff3c97cff2c5186309eaeaac716285513fb1023 100644
--- a/src/HAB/Solr/Command/Invoker.php
+++ b/src/HAB/Solr/Command/Invoker.php
@@ -72,7 +72,7 @@ class Invoker
      */
     public function invoke (CommandInterface $command, ParamBag $parameters = null)
     {
-        $params = $this->getParameters();
+        $params = clone($this->getParameters());
         if ($parameters) {
             $params->mergeWith($parameters);
         }