diff --git a/src/Form/AssignmentFilterType.php b/src/Form/AssignmentFilterType.php
index 945711f..d24370a 100644
--- a/src/Form/AssignmentFilterType.php
+++ b/src/Form/AssignmentFilterType.php
@@ -63,8 +63,8 @@ class AssignmentFilterType extends AbstractType
                 'label' => 'vergangene Einsätze anzeigen',
                 'required' => false,
             ])
-            ->add('syncedWithBusProNet', CheckboxType::class, [
-                'label' => 'in BusProNet hinterlegt',
+            ->add('notSyncedWithBusProNet', CheckboxType::class, [
+                'label' => 'nicht in BusProNet hinterlegt',
                 'required' => false,
             ])
             ->add('country', ChoiceType::class, [
diff --git a/src/Model/AssignmentFilterDto.php b/src/Model/AssignmentFilterDto.php
index 113e681..44d19fd 100644
--- a/src/Model/AssignmentFilterDto.php
+++ b/src/Model/AssignmentFilterDto.php
@@ -18,7 +18,7 @@ class AssignmentFilterDto extends AbstractFilterDto
     protected array $status = [];
     protected bool $includePast = false;
     protected ?string $country = null;
-    protected bool $syncedWithBusProNet = false;
+    protected bool $notSyncedWithBusProNet = false;
 
     public function getId(): ?int
     {
@@ -128,14 +128,14 @@ class AssignmentFilterDto extends AbstractFilterDto
         return $this;
     }
 
-    public function isSyncedWithBusProNet(): bool
+    public function isNotSyncedWithBusProNet(): bool
     {
-        return $this->syncedWithBusProNet;
+        return $this->notSyncedWithBusProNet;
     }
 
-    public function setSyncedWithBusProNet(bool $syncedWithBusProNet): static
+    public function setNotSyncedWithBusProNet(bool $notSyncedWithBusProNet): static
     {
-        $this->syncedWithBusProNet = $syncedWithBusProNet;
+        $this->notSyncedWithBusProNet = $notSyncedWithBusProNet;
 
         return $this;
     }
diff --git a/src/Repository/AssignmentRepository.php b/src/Repository/AssignmentRepository.php
index 339a4b1..105f851 100644
--- a/src/Repository/AssignmentRepository.php
+++ b/src/Repository/AssignmentRepository.php
@@ -186,10 +186,10 @@ class AssignmentRepository extends ServiceEntityRepository
             ;
         }
 
-        if (true === $filterDto->isSyncedWithBusProNet()) {
+        if (true === $filterDto->isNotSyncedWithBusProNet()) {
             $qb
                 ->andWhere($qb->expr()->eq('disposition.syncedWithBusProNet', ':syncedWithBusProNet'))
-                ->setParameter('syncedWithBusProNet', true)
+                ->setParameter('syncedWithBusProNet', false)
             ;
         }
     }
diff --git a/src/Service/Common/AssignmentFilterHandler.php b/src/Service/Common/AssignmentFilterHandler.php
index 5ae61f7..add9b7f 100644
--- a/src/Service/Common/AssignmentFilterHandler.php
+++ b/src/Service/Common/AssignmentFilterHandler.php
@@ -51,8 +51,8 @@ class AssignmentFilterHandler extends AbstractFilterHandler
         if (isset($data['country'])) {
             $filterDto->setCountry($data['country']);
         }
-        if (isset($data['synced_with_bus_pro_net'])) {
-            $filterDto->setSyncedWithBusProNet((bool) $data['synced_with_bus_pro_net']);
+        if (isset($data['not_synced_with_bus_pro_net'])) {
+            $filterDto->setNotSyncedWithBusProNet((bool) $data['not_synced_with_bus_pro_net']);
         }
 
         return $filterDto;
@@ -73,7 +73,7 @@ class AssignmentFilterHandler extends AbstractFilterHandler
             'status' => $filterDto->getStatus(),
             'include_past' => $filterDto->isIncludePast(),
             'country' => $filterDto->getCountry(),
-            'synced_with_bus_pro_net' => $filterDto->isSyncedWithBusProNet(),
+            'not_synced_with_bus_pro_net' => $filterDto->isNotSyncedWithBusProNet(),
         ]);
     }
 }
diff --git a/templates/common/modal_assignment_filter.html.twig b/templates/common/modal_assignment_filter.html.twig
index d1ba380..abf6b70 100644
--- a/templates/common/modal_assignment_filter.html.twig
+++ b/templates/common/modal_assignment_filter.html.twig
@@ -21,7 +21,7 @@
         {{ form_row(filterForm.country) }}
         <div class="grid grid-cols-2 gap-x-4 gap-y-2">
             {{ form_row(filterForm.includePast) }}
-            {{ form_row(filterForm.syncedWithBusProNet) }}
+            {{ form_row(filterForm.notSyncedWithBusProNet) }}
         </div>
     </div>
     <div class="flex items-center space-x-2">