diff --git a/src/nwbinspector/_dandi_inspection.py b/src/nwbinspector/_dandi_inspection.py
index 56a80ee13..b6afd971c 100644
--- a/src/nwbinspector/_dandi_inspection.py
+++ b/src/nwbinspector/_dandi_inspection.py
@@ -12,9 +12,9 @@ def inspect_dandiset(
     *,
     dandiset_id: str,
     dandiset_version: Union[str, Literal["draft"], None] = None,
-    checks: Optional[list] = None,
-    ignore: Optional[List[str]] = None,
-    select: Optional[List[str]] = None,
+    checks: Union[list, None] = None,
+    ignore: Union[List[str], None] = None,
+    select: Union[List[str], None] = None,
     importance_threshold: Union[str, Importance] = Importance.BEST_PRACTICE_SUGGESTION,
     client: Union["dandi.dandiapi.DandiAPIClient", None] = None,
 ) -> Iterable[InspectorMessage]:
@@ -87,9 +87,9 @@ def inspect_dandi_file_path(
     dandi_file_path: str,
     dandiset_id: str,
     dandiset_version: Union[str, Literal["draft"], None] = None,
-    checks: Optional[list] = None,
-    ignore: Optional[List[str]] = None,
-    select: Optional[List[str]] = None,
+    checks: Union[list, None] = None,
+    ignore: Union[List[str], None] = None,
+    select: Union[List[str], None] = None,
     importance_threshold: Union[str, Importance] = Importance.BEST_PRACTICE_SUGGESTION,
     client: Union["dandi.dandiapi.DandiAPIClient", None] = None,
 ) -> Iterable[InspectorMessage]: