New Delhi, Sept. 18 -- Shares of Tata Group companies came under heavy selling pressure in Friday's trade, September 18, with the combined market capitalisation of several listed group firms eroding by Rs.46,600 crore.

The sell-off came as an unprecedented boardroom revolt at Tata Sons pushed the 158-year-old conglomerate into a high-stakes governance crisis, while uncertainty over the holding company's potential listing added to investor concerns.

The sharp losses followed a dramatic turn of events at Tata Sons, the group's holding company. The board, on Thursday, asked Chairman Natarajan Chandrasekaran to continue for another five years and approved a potential public listing of the company by a majority vote, according to a Tata Sons...