diff --git a/ome_zarr/format.py b/ome_zarr/format.py
index d8c3a77b..2a6ab021 100644
--- a/ome_zarr/format.py
+++ b/ome_zarr/format.py
@@ -106,7 +106,7 @@ def init_store(self, path: str, mode: str = "r") -> FSStore:
 
         kwargs = {
             "dimension_separator": "/",
-            "normalize_keys": True,
+            "normalize_keys": False,
         }
 
         mkdir = True