diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index 90bd03513fe..f0fe7bf437c 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -4997,7 +4997,10 @@ abstract class CommonObject
 			{
     			foreach($extrafields->attributes[$this->table_element]['mandatoryfieldsofotherentities'] as  $tmpkey => $tmpval)
     			{
-    			    $sql.=",".$tmpkey;
+    			    if (! isset($extrafields->attributes[$this->table_element]['type'][$tmpkey]))    // If field not already added previously
+    			    {
+    			        $sql.=",".$tmpkey;
+    			    }
     			}
 			}
 			$sql .= ") VALUES (".$this->id;
@@ -5023,8 +5026,11 @@ abstract class CommonObject
 			{
 			    foreach($extrafields->attributes[$this->table_element]['mandatoryfieldsofotherentities'] as  $tmpkey => $tmpval)
     			{
-    			    if (in_array($tmpval, array('int', 'double'))) $sql.=", 0";
-    			    else $sql.=", ''";
+    			    if (! isset($extrafields->attributes[$this->table_element]['type'][$tmpkey]))    // If field not already added previously
+    			    {
+                        if (in_array($tmpval, array('int', 'double'))) $sql.=", 0";
+                        else $sql.=", ''";
+    			    }
     			}
 			}
 
diff --git a/htdocs/core/class/extrafields.class.php b/htdocs/core/class/extrafields.class.php
index 6e92509756f..6babf6709d8 100644
--- a/htdocs/core/class/extrafields.class.php
+++ b/htdocs/core/class/extrafields.class.php
@@ -796,7 +796,7 @@ class ExtraFields
 				{
 				    if ($tab->entity != 0 && $tab->entity != $conf->entity)
 				    {
-				        // This field is not in current entity. We discard but before we save it into the array of mandatory fields if it is a mandatory field
+				        // This field is not in current entity. We discard but before we save it into the array of mandatory fields if it is a mandatory field without default value
 				        if ($tab->fieldrequired && is_null($tab->fielddefault))
 				        {
 				            $this->attributes[$tab->elementtype]['mandatoryfieldsofotherentities'][$tab->name]=$tab->type;