Referring to Mistry's allegations in his letter to its board members that five major Tata firms may have to take potential write downs of Rs 1.18 lakh crore, Tata Sons questioned whether he had informed the respective boards of these companies and why was it not made public.
Arguing that he could not have 'discovered' such a large potential liability only a day or two after he was replaced, Tata Sons said, "It also suggests that he had no intention of or given up any attempt to revive the value of these companies."
Refuting Mistry's accusation of interference by the Tata Trusts, Tata Sons said it "was not only wrong in reality but has been twisted to mislead people".
It was only to to protect the assets of the Trusts - the most important and valuable being investments in Tata Sons -- that information relating to the operations of the company, which is an unlisted investment holding company need to be kept track of, it said.
Citing that there has been continuous decline in the income of Tata Sons from its large portfolio of investments other than TCS during the last four years of Mistry's regime, the statement said it reflected the corresponding decline in the many operating companies in which Tata Sons holds a significant shareholding.
Dividends received from all the other 40 companies excluding TCS has continuously declined from Rs 1,000 crore in 2012-13 to Rs 780 crore in 2015-16, including additional interim dividend of Rs 100 crore.
"While dividend income was declining, expenses (other than interest on debt) on staff increased from Rs 84 crore to Rs 180 crore and other expenses increased from Rs 220 crore in 2012-13 to Rs 290 crore in 2015 (excluding exceptional expenses)," Tata Sons said in its statement.
It further said impairment provisions increased from Rs 200 crore in 2012-13 to Rs 2,400 crore in 2015-16 "indicating inability to stem falling values and turn around the 'hot spots' referred to by Mr Mistry".
On the group's automobile venture, Tata Motors, Tata Sons said that during Mistry's leadership "there has been a perilous drop in market share in both passenger cars and commercial vehicle areas over the past three years".
"In passenger cars, in the year ended March 2013, the market share was 13 per cent which now stands at 5 per cent! ...However, even more concerning is the market share in commercial vehicles which in March 2013 stood at 60 per cent and now stands at (over) 40 per cent – the lowest in the company's history as the market leader in commercial vehicles," Tata Sons said.
While it did not make any mention of Nano, Tata Sons said the problems of Tata Motors are "masked by the performance and profitability of JlR as most references to Tata Motors are in consolidated form".