diff --git a/webviz_subsurface/_providers/ensemble_surface_provider/surface_array_server.py b/webviz_subsurface/_providers/ensemble_surface_provider/surface_array_server.py
index 5e42dcc4f..aa5d2dbbb 100644
--- a/webviz_subsurface/_providers/ensemble_surface_provider/surface_array_server.py
+++ b/webviz_subsurface/_providers/ensemble_surface_provider/surface_array_server.py
@@ -61,7 +61,6 @@ def __init__(self, app: Dash) -> None:
                 "CACHE_TYPE": "FileSystemCache",
                 "CACHE_DIR": cache_dir,
                 "CACHE_DEFAULT_TIMEOUT": 0,
-                "CACHE_OPTIONS": {"mode": 0o660},
             }
         )
         self._array_cache.init_app(app.server)
diff --git a/webviz_subsurface/_providers/ensemble_surface_provider/surface_image_server.py b/webviz_subsurface/_providers/ensemble_surface_provider/surface_image_server.py
index db823e177..94fd53963 100644
--- a/webviz_subsurface/_providers/ensemble_surface_provider/surface_image_server.py
+++ b/webviz_subsurface/_providers/ensemble_surface_provider/surface_image_server.py
@@ -56,7 +56,6 @@ def __init__(self, app: Dash) -> None:
                 "CACHE_TYPE": "FileSystemCache",
                 "CACHE_DIR": cache_dir,
                 "CACHE_DEFAULT_TIMEOUT": 0,
-                "CACHE_OPTIONS": {"mode": 0o660},
             }
         )
         self._image_cache.init_app(app.server)