diff --git a/dev/build/phpstan/phpstan-baseline.neon b/dev/build/phpstan/phpstan-baseline.neon
index a719087735f..32aec6d0659 100644
--- a/dev/build/phpstan/phpstan-baseline.neon
+++ b/dev/build/phpstan/phpstan-baseline.neon
@@ -1182,12 +1182,6 @@ parameters:
 			count: 1
 			path: ../../../htdocs/ai/admin/setup.php
 
-		-
-			message: '#^Call to function is_object\(\) with ActionComm\|Adherent\|Commande\|CommandeFournisseur\|Contact\|Contrat\|Expedition\|ExpenseReport\|Facture\|FactureFournisseur\|Fichinter\|Mo\|Product\|Project\|Propal\|Task will always evaluate to true\.$#'
-			identifier: function.alreadyNarrowedType
-			count: 2
-			path: ../../../htdocs/api/class/api_documents.class.php
-
 		-
 			message: '#^Variable \$modulepart in empty\(\) always exists and is not falsy\.$#'
 			identifier: empty.variable
diff --git a/htdocs/api/class/api_documents.class.php b/htdocs/api/class/api_documents.class.php
index b96ca75da94..a1a66cfb469 100644
--- a/htdocs/api/class/api_documents.class.php
+++ b/htdocs/api/class/api_documents.class.php
@@ -907,19 +907,18 @@ class Documents extends DolibarrApi
 				throw new RestException(500, 'Modulepart '.$modulepart.' not implemented yet.');
 			}
 
-			if (is_object($object)) {
-				if ($fetchbyid) {
-					// @phan-suppress-next-line PhanPluginSuspiciousParamPosition
-					$result = $object->fetch((int) $ref);
-				} else {
-					$result = $object->fetch(0, $ref);
-				}
+			// at this step $object is always an object
+			if ($fetchbyid) {
+				// @phan-suppress-next-line PhanPluginSuspiciousParamPosition
+				$result = $object->fetch((int) $ref);
+			} else {
+				$result = $object->fetch(0, $ref);
+			}
 
-				if ($result == 0) {
-					throw new RestException(404, "Object with ref '".$ref."' was not found.");
-				} elseif ($result < 0) {
-					throw new RestException(500, 'Error while fetching object: '.$object->error);
-				}
+			if ($result == 0) {
+				throw new RestException(404, "Object with ref '".$ref."' was not found.");
+			} elseif ($result < 0) {
+				throw new RestException(500, 'Error while fetching object: '.$object->error);
 			}
 
 			if (!($object->id > 0)) {
@@ -1056,7 +1055,8 @@ class Documents extends DolibarrApi
 		}
 
 		$moreinfo = array('note_private' => 'File uploaded using API /documents from IP '.getUserRemoteIP());
-		if (!empty($object) && is_object($object) && $object->id > 0) {
+		// $object may be null
+		if (is_object($object) && $object->id > 0) {
 			$moreinfo['src_object_type'] = $object->table_element;
 			$moreinfo['src_object_id'] = $object->id;
 		}