@TomAugspurger You're right    ``` python  In [2]: a = np.array([1, 2], dtype=object)    In [3]: a[:] = [(1, 2), (3, 4)]    In [4]: id(a), id(pd.Index(a, tupleize_cols=False).values.base)  Out[4]: (140686849540864, 140686849540864)  ```  sorry for the noise