diff --git a/scripts/masker/dma-collection-masker b/scripts/masker/dma-collection-masker
index ee25a420..809ce59a 100755
--- a/scripts/masker/dma-collection-masker
+++ b/scripts/masker/dma-collection-masker
@@ -433,7 +433,7 @@ def _metadata_from_filename(collection_file: Path) -> FileMetadata:
     """
     try:
         meta_values = collection_file.stem.split("__", maxsplit=2)[-1].split("_")[1:6]
-        meta_values[0] = parse_version(meta_values[0])  # type: ignore[call-overload]
+        meta_values[0] = str(parse_version(meta_values[0]))  # type: ignore[call-overload]
         meta_values.append("_".join(meta_values[1:3] + [meta_values[4]]))  # pkey
         meta_values.append("_".join(meta_values[1:5]))  # collection_key
         metadata = FileMetadata(*meta_values)