diff --git a/htdocs/compta/facture/class/api_invoices.class.php b/htdocs/compta/facture/class/api_invoices.class.php
index d8dd5dbeb1a..0640f1fdf4f 100644
--- a/htdocs/compta/facture/class/api_invoices.class.php
+++ b/htdocs/compta/facture/class/api_invoices.class.php
@@ -652,6 +652,49 @@ class Invoices extends DolibarrApi
     }
 
 
+     /**
+     * Insert a discount in a specific invoice
+     *
+     * @param int   $id             Id of invoice
+     * @param int   $discountId     Id of discount
+     *
+     * @url     POST {id}/adddiscount/{discountId}
+     *
+     * @return int
+     * @throws 400
+     * @throws 401
+     * @throws 404
+     * @throws 405
+     */
+    function addDiscount($id, $discountId) {
+
+        if(! DolibarrApiAccess::$user->rights->facture->creer) {
+                throw new RestException(401);
+        }
+        if(empty($id)) {
+                throw new RestException(400, 'Invoice ID is mandatory');
+        }
+        if(empty($discountId)) {
+                throw new RestException(400, 'Discount ID is mandatory');
+        }
+
+        if( ! DolibarrApi::_checkAccessToResource('facture',$id)) {
+                throw new RestException(401, 'Access not allowed for login '.DolibarrApiAccess::$user->login);
+        }
+
+        $result = $this->invoice->fetch($id);
+        if( ! $result ) {
+                throw new RestException(404, 'Invoice not found');
+        }
+
+        $result = $this->invoice->insert_discount($discountId);
+        if( $result < 0) {
+                throw new RestException(405, $this->invoice->error);
+        }
+
+        return $result;
+    }
+
     /**
      * Get a payment list of a given invoice
      *
@@ -691,7 +734,6 @@ class Invoices extends DolibarrApi
         return $result;
     }
 
-
     /**
      * Get a list of available assets (down-payments, avoirs)
      *
@@ -731,30 +773,30 @@ class Invoices extends DolibarrApi
         $return = array();
         foreach ($result as $invoiceID=>$line) {
 
-                if($invoiceID == $id) {         // ignore current invoice
-                        continue;
-                }
+		if($invoiceID == $id) {  	// ignore current invoice
+			continue;
+		}
 
-                $result = $this->invoice->fetch($invoiceID);
-                if( ! $result ) {
-                        throw new RestException(404, 'Invoice '.$invoiceID.' not found');
-                }
+		$result = $this->invoice->fetch($invoiceID);
+        	if( ! $result ) {
+                	throw new RestException(404, 'Invoice '.$invoiceID.' not found');
+        	}
 
                 $result = $this->invoice->getListOfPayments();
                 if( $result < 0) {
-                        throw new RestException(405, $this->invoice->error);
-                }
+                	throw new RestException(405, $this->invoice->error);
+        	}
 
-                if(count($result) == 0) {       // ignore unpaid invoices
-                        continue;
-                }
+		if(count($result) == 0) {	// ignore unpaid invoices
+			continue;
+		}
 
-                // format results
+		// format results
                 $line["id"] = $invoiceID;
-                $line["payments"] = $result;
-                $return[] = $line;
+		$line["payments"] = $result;
+                $return[] = $line; 
         }
-
+            
         return $return;
     }
 
diff --git a/htdocs/societe/class/api_thirdparties.class.php b/htdocs/societe/class/api_thirdparties.class.php
index 6ed404e28cd..ee1fd17d39a 100644
--- a/htdocs/societe/class/api_thirdparties.class.php
+++ b/htdocs/societe/class/api_thirdparties.class.php
@@ -338,6 +338,68 @@ class Thirdparties extends DolibarrApi
       return $this->company;
     }
 
+
+     /**
+     * Get exceptional discount of a thirdparty
+     *
+     * @param 	int 	$id             ID of the thirdparty
+     * @param 	string 	$filter    	Filter exceptional discount. "none" will return every discount, "available" returns unapplied discounts, "used" returns applied discounts   {@choice none,available,used}
+     * @param   string  $sortfield  	Sort field
+     * @param   string  $sortorder  	Sort order
+     * 
+     * @url     GET {id}/exceptionaldiscounts
+     * 
+     * @return array  List of deposit and credit notes
+     * 
+     * @throws 400
+     * @throws 401
+     * @throws 404
+     * @throws 503
+     */
+    function getExceptionalDiscount($id,$filter="none",$sortfield = "f.type", $sortorder = 'ASC')
+    {
+      if(! DolibarrApiAccess::$user->rights->societe->lire) {
+        throw new RestException(401);
+      }
+
+      if(empty($id)) {
+        throw new RestException(400, 'Thirdparty ID is mandatory');
+      }
+
+      if( ! DolibarrApi::_checkAccessToResource('societe',$this->company->id)) {
+        throw new RestException(401, 'Access not allowed for login '.DolibarrApiAccess::$user->login);
+      }
+
+      $result = $this->company->fetch($id);
+      if( ! $result ) {
+          throw new RestException(404, 'Thirdparty not found');
+      }
+
+
+      $sql = "SELECT f.facnumber, f.type as factype, re.fk_facture_source, re.rowid, re.amount_ht, re.amount_tva, re.amount_ttc, re.description, re.fk_facture, re.fk_facture_line";
+      $sql .= " FROM llx_societe_remise_except as re, llx_facture as f";
+      $sql .= " WHERE f.rowid = re.fk_facture_source AND re.fk_soc = ".$id;
+      if ($filter == "available")  $sql .= " AND re.fk_facture IS NULL AND re.fk_facture_line IS NULL";
+      if ($filter == "used")  $sql .= " AND (re.fk_facture IS NOT NULL OR re.fk_facture_line IS NOT NULL)";
+
+      $sql.= $this->db->order($sortfield, $sortorder);
+
+      $result = $this->db->query($sql);
+      if( ! $result ) {
+          throw new RestException(503, $this->db->lasterror());
+      } else {
+          $num = $this->db->num_rows($result);
+          while ( $obj = $this->db->fetch_object($result) ) {
+              $obj_ret[] = $obj;
+          }
+
+      }
+
+      return $obj_ret;
+    }
+
+
+
 	/**
 	 * Clean sensible object datas
 	 *