diff --git a/htdocs/product/inventory/class/inventory.class.php b/htdocs/product/inventory/class/inventory.class.php
index be6ca6aa930..cefdfc37972 100644
--- a/htdocs/product/inventory/class/inventory.class.php
+++ b/htdocs/product/inventory/class/inventory.class.php
@@ -130,9 +130,18 @@ class Inventory extends CommonObject
 	 * @var int Status
 	 */
 	public $status;
-
+    
+	/**
+	 * @var integer|string date_creation
+	 */
 	public $date_creation;
+	
+	/**
+	 * @var integer|string date_validation
+	 */
 	public $date_validation;
+	
+	
 	public $tms;
 
 	/**