diff --git a/src/Bundle/ChillDocStoreBundle/Service/Signature/Driver/BaseSigner/PdfSignedMessageHandler.php b/src/Bundle/ChillDocStoreBundle/Service/Signature/Driver/BaseSigner/PdfSignedMessageHandler.php
index 4002b107b..81fb97dbf 100644
--- a/src/Bundle/ChillDocStoreBundle/Service/Signature/Driver/BaseSigner/PdfSignedMessageHandler.php
+++ b/src/Bundle/ChillDocStoreBundle/Service/Signature/Driver/BaseSigner/PdfSignedMessageHandler.php
@@ -11,6 +11,9 @@ declare(strict_types=1);
 
 namespace Chill\DocStoreBundle\Service\Signature\Driver\BaseSigner;
 
+use Chill\DocStoreBundle\Service\StoredObjectManagerInterface;
+use Chill\MainBundle\Repository\Workflow\EntityWorkflowStepSignatureRepository;
+use Chill\MainBundle\Workflow\EntityWorkflowManager;
 use Psr\Log\LoggerInterface;
 use Symfony\Component\Messenger\Handler\MessageHandlerInterface;
 
@@ -23,10 +26,27 @@ final readonly class PdfSignedMessageHandler implements MessageHandlerInterface
 
     public function __construct(
         private LoggerInterface $logger,
+        private EntityWorkflowManager $entityWorkflowManager,
+        private StoredObjectManagerInterface $storedObjectManager,
+        private EntityWorkflowStepSignatureRepository $entityWorkflowStepSignatureRepository,
     ) {}
 
     public function __invoke(PdfSignedMessage $message): void
     {
         $this->logger->info(self::P.'a message is received', ['signaturedId' => $message->signatureId]);
+
+        $signature = $this->entityWorkflowStepSignatureRepository->find($message->signatureId);
+
+        if (null === $signature) {
+            throw new \RuntimeException('no signature found');
+        }
+
+        $storedObject = $this->entityWorkflowManager->getAssociatedStoredObject($signature->getStep()->getEntityWorkflow());
+
+        if (null === $storedObject) {
+            throw new \RuntimeException('no stored object found');
+        }
+
+        $this->storedObjectManager->write($storedObject, $message->content);
     }
 }
diff --git a/src/Bundle/ChillDocStoreBundle/Tests/Service/Signature/Driver/BaseSigner/PdfSignedMessageHandlerTest.php b/src/Bundle/ChillDocStoreBundle/Tests/Service/Signature/Driver/BaseSigner/PdfSignedMessageHandlerTest.php
new file mode 100644
index 000000000..62d50c03f
--- /dev/null
+++ b/src/Bundle/ChillDocStoreBundle/Tests/Service/Signature/Driver/BaseSigner/PdfSignedMessageHandlerTest.php
@@ -0,0 +1,84 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\DocStoreBundle\Tests\Service\Signature\Driver\BaseSigner;
+
+use Chill\DocStoreBundle\Entity\StoredObject;
+use Chill\DocStoreBundle\Service\Signature\Driver\BaseSigner\PdfSignedMessage;
+use Chill\DocStoreBundle\Service\Signature\Driver\BaseSigner\PdfSignedMessageHandler;
+use Chill\DocStoreBundle\Service\StoredObjectManagerInterface;
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\Workflow\EntityWorkflow;
+use Chill\MainBundle\Entity\Workflow\EntityWorkflowStepSignature;
+use Chill\MainBundle\Repository\Workflow\EntityWorkflowStepSignatureRepository;
+use Chill\MainBundle\Workflow\EntityWorkflowManager;
+use Chill\MainBundle\Workflow\WorkflowTransitionContextDTO;
+use Chill\PersonBundle\Entity\Person;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\NullLogger;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+class PdfSignedMessageHandlerTest extends TestCase
+{
+    public function testThatObjectIsWrittenInStoredObjectManagerHappyScenario(): void
+    {
+        // a dummy stored object
+        $storedObject = new StoredObject();
+        // build the associated EntityWorkflow, with one step with a person signature
+        $entityWorkflow = new EntityWorkflow();
+        $dto = new WorkflowTransitionContextDTO($entityWorkflow);
+        $dto->futurePersonSignatures[] = new Person();
+        $entityWorkflow->setStep('new_step', $dto, 'new_transition', new \DateTimeImmutable(), new User());
+        $step = $entityWorkflow->getCurrentStep();
+        $signature = $step->getSignatures()->first();
+
+        $handler = new PdfSignedMessageHandler(
+            new NullLogger(),
+            $this->buildEntityWorkflowManager($storedObject),
+            $this->buildStoredObjectManager($storedObject, $expectedContent = '1234'),
+            $this->buildSignatureRepository($signature)
+        );
+
+        // we simply call the handler. The mocked StoredObjectManager will check that the "write" method is invoked once
+        // with the content "1234"
+        $handler(new PdfSignedMessage(10, $expectedContent));
+    }
+
+    private function buildSignatureRepository(EntityWorkflowStepSignature $signature): EntityWorkflowStepSignatureRepository
+    {
+        $entityWorkflowStepSignatureRepository = $this->createMock(EntityWorkflowStepSignatureRepository::class);
+        $entityWorkflowStepSignatureRepository->method('find')->with($this->isType('int'))->willReturn($signature);
+
+        return $entityWorkflowStepSignatureRepository;
+    }
+
+    private function buildEntityWorkflowManager(?StoredObject $associatedStoredObject): EntityWorkflowManager
+    {
+        $entityWorkflowManager = $this->createMock(EntityWorkflowManager::class);
+        $entityWorkflowManager->method('getAssociatedStoredObject')->willReturn($associatedStoredObject);
+
+        return $entityWorkflowManager;
+    }
+
+    private function buildStoredObjectManager(StoredObject $expectedStoredObject, string $expectedContent): StoredObjectManagerInterface
+    {
+        $storedObjectManager = $this->createMock(StoredObjectManagerInterface::class);
+        $storedObjectManager->expects($this->once())
+            ->method('write')
+            ->with($this->identicalTo($expectedStoredObject), $expectedContent);
+
+        return $storedObjectManager;
+    }
+}