diff --git a/pandas/core/groupby/ops.py b/pandas/core/groupby/ops.py
index d16ffbca16a3d..1c18ef891b8c5 100644
--- a/pandas/core/groupby/ops.py
+++ b/pandas/core/groupby/ops.py
@@ -7,7 +7,7 @@
 """
 
 import collections
-from typing import Dict, Hashable, List, Optional, Sequence, Tuple, Type
+from typing import Dict, Generic, Hashable, List, Optional, Sequence, Tuple, Type
 
 import numpy as np
 
@@ -866,7 +866,7 @@ def _is_indexed_like(obj, axes, axis: int) -> bool:
 # Splitting / application
 
 
-class DataSplitter:
+class DataSplitter(Generic[FrameOrSeries]):
     def __init__(self, data: FrameOrSeries, labels, ngroups: int, axis: int = 0):
         self.data = data
         self.labels = ensure_int64(labels)
diff --git a/setup.cfg b/setup.cfg
index 8ec10e7db5a5c..ee28646d722f2 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -172,9 +172,6 @@ check_untyped_defs=False
 [mypy-pandas.core.groupby.grouper]
 check_untyped_defs=False
 
-[mypy-pandas.core.groupby.ops]
-check_untyped_defs=False
-
 [mypy-pandas.core.indexes.base]
 check_untyped_defs=False