diff --git a/app/Harvest/Importers/GmuhkItemImporter.php b/app/Harvest/Importers/GmuhkItemImporter.php
index 91909ffcf..a15c56dc7 100644
--- a/app/Harvest/Importers/GmuhkItemImporter.php
+++ b/app/Harvest/Importers/GmuhkItemImporter.php
@@ -45,11 +45,14 @@ public function import(array $row, Progress $result) {
                 return $authorities->count() === 1;
             })
             ->map->first()
-            ->mapWithKeys(
-                fn(Authority $authority, $author) => [
-                    $authority->id => ['role' => AuthorityMatcher::parse($author)['alt_name']],
-                ]
-            );
+            ->mapWithKeys(function(Authority $authority, $author) {
+                $pivotData = [];
+                if ($role = AuthorityMatcher::parse($author)['alt_name']) {
+                    $pivotData['role'] = $role;
+                }
+
+                return [$authority->id => $pivotData];
+            });
 
         $item->syncMatchedAuthorities($matches);
 
diff --git a/app/Item.php b/app/Item.php
index 60361409e..7a847b3c4 100644
--- a/app/Item.php
+++ b/app/Item.php
@@ -790,7 +790,9 @@ public function syncMatchedAuthorities(\Illuminate\Support\Collection|array $ids
 
         // Update existing pivot data
         foreach ($idsWithPivotData as $id => $pivotData) {
-            $this->authorities()->updateExistingPivot($id, $pivotData);
+            if ($pivotData) {
+                $this->authorities()->updateExistingPivot($id, $pivotData);
+            }
         }
 
         // Create new authorities
diff --git a/tests/Models/ItemTest.php b/tests/Models/ItemTest.php
index b129d0569..d18526824 100644
--- a/tests/Models/ItemTest.php
+++ b/tests/Models/ItemTest.php
@@ -258,4 +258,40 @@ public function testSyncMatchedAuthoritiesAddsNew()
             'automatically_matched' => true,
         ]);
     }
+
+    public function testSyncMatchedAuthoritiesCreatesWithoutPivotData()
+    {
+        $item = Item::factory()->create();
+        $authority = Authority::factory()->create();
+
+        $item->syncMatchedAuthorities([
+            $authority->id => [],
+        ]);
+
+        $this->assertDatabaseHas('authority_item', [
+            'authority_id' => $authority->id,
+            'item_id' => $item->id,
+            'role' => null,
+            'automatically_matched' => true,
+        ]);
+    }
+
+    public function testSyncMatchedAuthoritiesUpdatesWithoutPivotData()
+    {
+        $item = Item::factory()->create();
+        $authority = Authority::factory()->create();
+        $item->authorities()->sync([
+            $authority->id => ['role' => 'author'],
+        ]);
+
+        $item->syncMatchedAuthorities([
+            $authority->id => [],
+        ]);
+
+        $this->assertDatabaseHas('authority_item', [
+            'authority_id' => $authority->id,
+            'item_id' => $item->id,
+            'role' => 'author',
+        ]);
+    }
 }