diff --git a/htdocs/core/ajax/onlineSign.php b/htdocs/core/ajax/onlineSign.php
index 56cc79662ae..67c3c989a3a 100644
--- a/htdocs/core/ajax/onlineSign.php
+++ b/htdocs/core/ajax/onlineSign.php
@@ -73,7 +73,7 @@ if ($type == 'proposal') {
 	$securekeyseed = getDolGlobalString('PROPOSAL_ONLINE_SIGNATURE_SECURITY_TOKEN');
 }
 
-if (!dol_verifyHash($securekeyseed.$type.$ref, $SECUREKEY, '0')) {
+if (!dol_verifyHash($securekeyseed.$type.$ref.(empty($conf->multicompany->enabled) ? '' : $entity), $SECUREKEY, '0')) {
 	http_response_code(403);
 	print 'Bad value for securitykey. Value provided '.dol_escape_htmltag($SECUREKEY).' does not match expected value for ref='.dol_escape_htmltag($ref);
 	exit(-1);
diff --git a/htdocs/core/lib/signature.lib.php b/htdocs/core/lib/signature.lib.php
index 33b0a1e8e5e..0351043b110 100644
--- a/htdocs/core/lib/signature.lib.php
+++ b/htdocs/core/lib/signature.lib.php
@@ -91,7 +91,7 @@ function getOnlineSignatureUrl($mode, $type, $ref = '', $localorexternal = 1)
 		if ($mode == 1) {
 			$out .= "hash('".$securekeyseed."' + '".$type."' + proposal_ref)";
 		} else {
-			$out .= '&securekey='.dol_hash($securekeyseed.$type.$ref, '0');
+			$out .= '&securekey='.dol_hash($securekeyseed.$type.$ref.(empty($conf->multicompany->enabled) ? '' : $object->entity), '0');
 		}
 		/*
 		if ($mode == 1) {
diff --git a/htdocs/public/onlinesign/newonlinesign.php b/htdocs/public/onlinesign/newonlinesign.php
index 5dca1604f58..a3ad1eaf645 100644
--- a/htdocs/public/onlinesign/newonlinesign.php
+++ b/htdocs/public/onlinesign/newonlinesign.php
@@ -139,7 +139,7 @@ if ($source == 'proposal') {
 	$securekeyseed = $conf->global->PROPOSAL_ONLINE_SIGNATURE_SECURITY_TOKEN;
 }
 
-if (!dol_verifyHash($securekeyseed.$type.$ref, $SECUREKEY, '0')) {
+if (!dol_verifyHash($securekeyseed.$type.$ref.(empty($conf->multicompany->enabled) ? '' : $entity), $SECUREKEY, '0')) {
 	http_response_code(403);
 	print 'Bad value for securitykey. Value provided '.dol_escape_htmltag($SECUREKEY).' does not match expected value for ref='.dol_escape_htmltag($ref);
 	exit(-1);
@@ -292,7 +292,6 @@ if ($source == 'proposal') {
 	$result = $object->fetch_thirdparty($object->socid);
 
 	// Creditor
-
 	print '<tr class="CTableRow2"><td class="CTableRow2">'.$langs->trans("Creditor");
 	print '</td><td class="CTableRow2">';
 	print img_picto('', 'company', 'class="pictofixedwidth"');
@@ -301,7 +300,6 @@ if ($source == 'proposal') {
 	print '</td></tr>'."\n";
 
 	// Debitor
-
 	print '<tr class="CTableRow2"><td class="CTableRow2">'.$langs->trans("ThirdParty");
 	print '</td><td class="CTableRow2">';
 	print img_picto('', 'company', 'class="pictofixedwidth"');
@@ -309,14 +307,12 @@ if ($source == 'proposal') {
 	print '</td></tr>'."\n";
 
 	// Amount
-
 	print '<tr class="CTableRow2"><td class="CTableRow2">'.$langs->trans("Amount");
 	print '</td><td class="CTableRow2">';
 	print '<b>'.price($object->total_ttc, 0, $langs, 1, -1, -1, $conf->currency).'</b>';
 	print '</td></tr>'."\n";
 
 	// Object
-
 	$text = '<b>'.$langs->trans("SignatureProposalRef", $object->ref).'</b>';
 	print '<tr class="CTableRow2"><td class="CTableRow2">'.$langs->trans("Designation");
 	print '</td><td class="CTableRow2">'.$text;