diff --git a/htdocs/core/lib/pdf.lib.php b/htdocs/core/lib/pdf.lib.php
index 3ac72e0d2c2..a1f7516bba9 100644
--- a/htdocs/core/lib/pdf.lib.php
+++ b/htdocs/core/lib/pdf.lib.php
@@ -1351,7 +1351,7 @@ function pdf_writelinedesc(&$pdf, $object, $i, $outputlangs, $w, $h, $posx, $pos
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = empty($object->lines[$i]->special_code) ? '' : $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('pdf'=>$pdf, 'i'=>$i, 'outputlangs'=>$outputlangs, 'w'=>$w, 'h'=>$h, 'posx'=>$posx, 'posy'=>$posy, 'hideref'=>$hideref, 'hidedesc'=>$hidedesc, 'issupplierline'=>$issupplierline, 'special_code'=>$special_code);
@@ -1693,7 +1693,7 @@ function pdf_getlinenum($object, $i, $outputlangs, $hidedetails = 0)
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -1726,7 +1726,7 @@ function pdf_getlineref($object, $i, $outputlangs, $hidedetails = 0)
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -1758,7 +1758,7 @@ function pdf_getlineref_supplier($object, $i, $outputlangs, $hidedetails = 0)
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -1789,8 +1789,8 @@ function pdf_getlinevatrate($object, $i, $outputlangs, $hidedetails = 0)
 	$reshook = 0;
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduce this test in the pdf_xxx function if you don't want your hook to run
-		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		$special_code = empty($object->lines[$i]) ? '' : $object->lines[$i]->special_code;
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -1856,8 +1856,8 @@ function pdf_getlineupexcltax($object, $i, $outputlangs, $hidedetails = 0)
 	$reshook = 0;
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
-		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		$special_code = empty($object->lines[$i]) ? '' : $object->lines[$i]->special_code;
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -1900,7 +1900,7 @@ function pdf_getlineupwithtax($object, $i, $outputlangs, $hidedetails = 0)
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -1936,8 +1936,8 @@ function pdf_getlineqty($object, $i, $outputlangs, $hidedetails = 0)
 	$reshook = 0;
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
-		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		$special_code = empty($object->lines[$i]) ? '' : $object->lines[$i]->special_code;
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -1977,7 +1977,7 @@ function pdf_getlineqty_asked($object, $i, $outputlangs, $hidedetails = 0)
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -2017,7 +2017,7 @@ function pdf_getlineqty_shipped($object, $i, $outputlangs, $hidedetails = 0)
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -2057,7 +2057,7 @@ function pdf_getlineqty_keeptoship($object, $i, $outputlangs, $hidedetails = 0)
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -2098,7 +2098,7 @@ function pdf_getlineunit($object, $i, $outputlangs, $hidedetails = 0, $hookmanag
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array(
@@ -2143,7 +2143,7 @@ function pdf_getlineremisepercent($object, $i, $outputlangs, $hidedetails = 0)
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
@@ -2187,7 +2187,7 @@ function pdf_getlineprogress($object, $i, $outputlangs, $hidedetails = 0, $hookm
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i' => $i, 'outputlangs' => $outputlangs, 'hidedetails' => $hidedetails, 'special_code' => $special_code);
@@ -2239,8 +2239,8 @@ function pdf_getlinetotalexcltax($object, $i, $outputlangs, $hidedetails = 0)
 	$result = '';
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
-		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		$special_code = empty($object->lines[$i]) ? '' : $object->lines[$i]->special_code;
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code, 'sign'=>$sign);
@@ -2252,7 +2252,7 @@ function pdf_getlinetotalexcltax($object, $i, $outputlangs, $hidedetails = 0)
 		}
 	}
 	if (empty($reshook)) {
-		if ($object->lines[$i]->special_code == 3) {
+		if (!empty($object->lines[$i]) && $object->lines[$i]->special_code == 3) {
 			$result .= $outputlangs->transnoentities("Option");
 		} elseif (empty($hidedetails) || $hidedetails > 1) {
 			$total_ht = (!empty($conf->multicurrency->enabled) && $object->multicurrency_tx != 1 ? $object->lines[$i]->multicurrency_total_ht : $object->lines[$i]->total_ht);
@@ -2296,7 +2296,7 @@ function pdf_getlinetotalwithtax($object, $i, $outputlangs, $hidedetails = 0)
 	//if (is_object($hookmanager) && ( (isset($object->lines[$i]->product_type) && $object->lines[$i]->product_type == 9 && ! empty($object->lines[$i]->special_code)) || ! empty($object->lines[$i]->fk_parent_line) ) )
 	if (is_object($hookmanager)) {   // Old code is commented on preceding line. Reproduct this test in the pdf_xxx function if you don't want your hook to run
 		$special_code = $object->lines[$i]->special_code;
-		if (!empty($object->lines[$i]->fk_parent_line)) {
+		if (!empty($object->lines[$i]->fk_parent_line) && $object->lines[$i]->fk_parent_line > 0) {
 			$special_code = $object->getSpecialCode($object->lines[$i]->fk_parent_line);
 		}
 		$parameters = array('i'=>$i, 'outputlangs'=>$outputlangs, 'hidedetails'=>$hidedetails, 'special_code'=>$special_code);
diff --git a/htdocs/fourn/class/fournisseur.commande.class.php b/htdocs/fourn/class/fournisseur.commande.class.php
index 8b69f763a83..30b0643a512 100644
--- a/htdocs/fourn/class/fournisseur.commande.class.php
+++ b/htdocs/fourn/class/fournisseur.commande.class.php
@@ -2854,7 +2854,7 @@ class CommandeFournisseur extends CommonOrder
 			$this->line->localtax2_type = empty($localtaxes_type[2]) ? '' : $localtaxes_type[2];
 			$this->line->remise_percent = $remise_percent;
 			$this->line->subprice       = $pu_ht;
-			$this->line->rang           = $this->rang;
+			$this->line->rang           = $oldline->rang;
 			$this->line->info_bits      = $info_bits;
 			$this->line->total_ht       = $total_ht;
 			$this->line->total_tva      = $total_tva;
@@ -2862,7 +2862,7 @@ class CommandeFournisseur extends CommonOrder
 			$this->line->total_localtax2 = $total_localtax2;
 			$this->line->total_ttc      = $total_ttc;
 			$this->line->product_type   = $type;
-			$this->line->special_code   = $this->special_code;
+			$this->line->special_code   = $oldline->special_code;
 			$this->line->origin         = $this->origin;
 			$this->line->fk_unit        = $fk_unit;