diff --git a/apis/python/src/tiledbsoma/_tdb_handles.py b/apis/python/src/tiledbsoma/_tdb_handles.py
index 5968391bea..2d6aed8baf 100644
--- a/apis/python/src/tiledbsoma/_tdb_handles.py
+++ b/apis/python/src/tiledbsoma/_tdb_handles.py
@@ -129,7 +129,7 @@ def open(
                     handle._do_initial_reads(auxiliary_reader)
             else:
                 handle._do_initial_reads(tdb)
-        except tiledb.TileDBError as tdbe:
+        except (RuntimeError, tiledb.TileDBError) as tdbe:
             if is_does_not_exist_error(tdbe):
                 raise DoesNotExistError(f"{uri!r} does not exist") from tdbe
             raise
diff --git a/apis/python/src/tiledbsoma/_tiledb_object.py b/apis/python/src/tiledbsoma/_tiledb_object.py
index cc9f863bf5..ad51b62646 100644
--- a/apis/python/src/tiledbsoma/_tiledb_object.py
+++ b/apis/python/src/tiledbsoma/_tiledb_object.py
@@ -270,7 +270,7 @@ def exists(
                 if not isinstance(md_type, str):
                     return False
                 return md_type.lower() == cls.soma_type.lower()
-        except (SOMAError, tiledb.cc.TileDBError):
+        except (RuntimeError, SOMAError, tiledb.cc.TileDBError):
             return False
 
     @classmethod