The views come in the wake of independent directors of Tata group's hospitality arm Indian Hotels endorsing the leadership of Cyrus Mistry while expressing their 'unanimous' full confidence in him.
Mistry was sacked as chairman by the board of Tata Sons - the holding company of group firms - but he continues to chair the boards of various entities.
"I don't want to comment on any particular company or group. But the independent directors have the fiduciary duty to perform and that they have their loyalty and obligation to all their shareholders," Sinha told reporters on the sidelines of a CII event here.
Currently, Mistry is chairman of seven listed group firms -- Tata Steel, Tata Motors, Indian Hotels Company, Tata Power, Tata Chemicals and Tata Global Beverages.