diff --git a/backend/src/main/java/org/raddatz/familienarchiv/dto/DocumentBatchMetadataDTO.java b/backend/src/main/java/org/raddatz/familienarchiv/dto/DocumentBatchMetadataDTO.java
index 93e17fbf..399105d9 100644
--- a/backend/src/main/java/org/raddatz/familienarchiv/dto/DocumentBatchMetadataDTO.java
+++ b/backend/src/main/java/org/raddatz/familienarchiv/dto/DocumentBatchMetadataDTO.java
@@ -13,6 +13,6 @@ public class DocumentBatchMetadataDTO {
     private List<UUID> receiverIds;
     private LocalDate documentDate;
     private String location;
-    private String tags;
+    private List<String> tagNames;
     private Boolean metadataComplete;
 }
diff --git a/backend/src/main/java/org/raddatz/familienarchiv/service/DocumentService.java b/backend/src/main/java/org/raddatz/familienarchiv/service/DocumentService.java
index 01ea544d..dac82517 100644
--- a/backend/src/main/java/org/raddatz/familienarchiv/service/DocumentService.java
+++ b/backend/src/main/java/org/raddatz/familienarchiv/service/DocumentService.java
@@ -166,11 +166,9 @@ public class DocumentService {
         if (metadata.getMetadataComplete() != null) {
             doc.setMetadataComplete(metadata.getMetadataComplete());
         }
-        if (metadata.getTags() != null && !metadata.getTags().isBlank()) {
-            List<String> tagNames = Arrays.stream(metadata.getTags().split(","))
-                    .map(String::trim).filter(s -> !s.isEmpty()).toList();
+        if (metadata.getTagNames() != null && !metadata.getTagNames().isEmpty()) {
             UUID docId = doc.getId();
-            updateDocumentTags(docId, tagNames);
+            updateDocumentTags(docId, metadata.getTagNames());
             doc = documentRepository.findById(docId)
                     .orElseThrow(() -> DomainException.notFound(ErrorCode.DOCUMENT_NOT_FOUND, "Not found after batch metadata: " + docId));
         }
diff --git a/backend/src/test/java/org/raddatz/familienarchiv/controller/DocumentControllerTest.java b/backend/src/test/java/org/raddatz/familienarchiv/controller/DocumentControllerTest.java
index 828e8402..b80ed173 100644
--- a/backend/src/test/java/org/raddatz/familienarchiv/controller/DocumentControllerTest.java
+++ b/backend/src/test/java/org/raddatz/familienarchiv/controller/DocumentControllerTest.java
@@ -886,6 +886,30 @@ class DocumentControllerTest {
                 .andExpect(status().isBadRequest());
     }
 
+    @Test
+    @WithMockUser(authorities = "WRITE_ALL")
+    void quickUpload_withMetadata_tagNamesJsonArray_parsedCorrectly() throws Exception {
+        Document doc = Document.builder().id(UUID.randomUUID()).title("brief").originalFilename("brief.pdf").build();
+        when(userService.findByEmail(any())).thenReturn(AppUser.builder().id(UUID.randomUUID()).build());
+
+        org.mockito.ArgumentCaptor<DocumentBatchMetadataDTO> captor =
+                org.mockito.ArgumentCaptor.forClass(DocumentBatchMetadataDTO.class);
+        when(documentService.storeDocumentWithBatchMetadata(any(), captor.capture(), anyInt(), any()))
+                .thenReturn(new DocumentService.StoreResult(doc, true));
+
+        org.springframework.mock.web.MockMultipartFile file =
+                new org.springframework.mock.web.MockMultipartFile("files", "brief.pdf", "application/pdf", new byte[]{1});
+        org.springframework.mock.web.MockMultipartFile metadata =
+                new org.springframework.mock.web.MockMultipartFile("metadata", "metadata", "application/json",
+                        "{\"tagNames\":[\"Briefwechsel\",\"Krieg\"]}".getBytes());
+
+        mockMvc.perform(multipart("/api/documents/quick-upload").file(file).file(metadata))
+                .andExpect(status().isOk());
+
+        org.assertj.core.api.Assertions.assertThat(captor.getValue().getTagNames())
+                .containsExactly("Briefwechsel", "Krieg");
+    }
+
     @Test
     @WithMockUser(authorities = "WRITE_ALL")
     void quickUpload_returns400_whenBatchExceedsCap() throws Exception {