diff --git a/htdocs/core/class/conf.class.php b/htdocs/core/class/conf.class.php
index 60ee78bbff5..023546494b6 100644
--- a/htdocs/core/class/conf.class.php
+++ b/htdocs/core/class/conf.class.php
@@ -532,15 +532,15 @@ class Conf
 			if (!empty($this->productbatch->enabled)) {
 				$this->global->STOCK_CALCULATE_ON_BILL = 0;
 				$this->global->STOCK_CALCULATE_ON_VALIDATE_ORDER = 0;
-				$this->global->STOCK_CALCULATE_ON_SHIPMENT = 1;
-				$this->global->STOCK_CALCULATE_ON_SHIPMENT_CLOSE = 0;
+				if (empty($this->global->STOCK_CALCULATE_ON_SHIPMENT_CLOSE)) $this->global->STOCK_CALCULATE_ON_SHIPMENT = 1;
+				if (empty($this->global->STOCK_CALCULATE_ON_SHIPMENT)) $this->global->STOCK_CALCULATE_ON_SHIPMENT_CLOSE = 1;
 				$this->global->STOCK_CALCULATE_ON_SUPPLIER_BILL = 0;
 				$this->global->STOCK_CALCULATE_ON_SUPPLIER_VALIDATE_ORDER = 0;
 				if (empty($this->reception->enabled)) {
 					$this->global->STOCK_CALCULATE_ON_SUPPLIER_DISPATCH_ORDER = 1;
 				} else {
-					$this->global->STOCK_CALCULATE_ON_RECEPTION = 1;
-					$this->global->STOCK_CALCULATE_ON_RECEPTION_CLOSE = 0;
+					if (empty($this->global->STOCK_CALCULATE_ON_RECEPTION_CLOSE)) $this->global->STOCK_CALCULATE_ON_RECEPTION = 1;
+					if (empty($this->global->STOCK_CALCULATE_ON_RECEPTION)) $this->global->STOCK_CALCULATE_ON_RECEPTION_CLOSE = 1;
 				}
 			}