diff --git a/src/main/kotlin/dev/pcvolkmer/onco/grzmetadataprocessor/data/File.kt b/src/main/kotlin/dev/pcvolkmer/onco/grzmetadataprocessor/data/File.kt
index b361678..66e5317 100644
--- a/src/main/kotlin/dev/pcvolkmer/onco/grzmetadataprocessor/data/File.kt
+++ b/src/main/kotlin/dev/pcvolkmer/onco/grzmetadataprocessor/data/File.kt
@@ -14,7 +14,7 @@ import kotlin.io.path.inputStream
 @Table("tbl_file")
 data class File(
     @Id val id: Long? = null,
-    val labDataId: Long?,
+    var labDataId: Long?,
     val filePath: String? = null,
     val fileType: FileType? = null,
     var fileChecksum: String = "",
diff --git a/src/main/kotlin/dev/pcvolkmer/onco/grzmetadataprocessor/web/FileController.kt b/src/main/kotlin/dev/pcvolkmer/onco/grzmetadataprocessor/web/FileController.kt
index 971f688..497c185 100644
--- a/src/main/kotlin/dev/pcvolkmer/onco/grzmetadataprocessor/web/FileController.kt
+++ b/src/main/kotlin/dev/pcvolkmer/onco/grzmetadataprocessor/web/FileController.kt
@@ -54,7 +54,11 @@ class FileController(
 
     @DeleteMapping(path = ["/labdatas/{labDataId}/files/{fileId}"])
     fun deleteFile(@PathVariable fileId: Long, @PathVariable labDataId: Long, model: Model): String {
-        fileRepository.deleteById(fileId)
+        val file = fileRepository.findById(fileId)
+        file.ifPresent {
+            it.apply { this.labDataId = null }
+            fileRepository.save(it)
+        }
         model.addAttribute("fileId", fileId)
         model.addAttribute("files", fileRepository.findByLabDataId(labDataId))
         return "files"