Under the Hindu Succession Act, 1956, even if the deceased was not entitled to claim partition:

The Explanation to s. 7(1) of the Hindu Succession Act, 1956 deems a per capita partition immediately before death among all members then living, "whether he or she was entitled to claim such partition or not" under that law. So inability to claim partition does not stop a notional share from being worked out and passing by succession.