Here are the 10 facts of the story:
Cyrus Mistry, 48, has denied reports that he too has initiated legal action."Tatas have filed caveats seeking notice from Cyrus Mistry fearing legal action. Cyrus has not filed any caveats. He has already made a statement that such concerns are misplaced at this stage," his office said.
Cyrus Mistry's removal was announced by Tata Sons, the holding company of India's biggest conglomerate, after a board meeting on Monday. Shares of most Tata group companies ended lower on Tuesday.
At the board meeting, sources said, Mr Mistry called his removal illegal, arguing that he should be given a 15-day notice to make a case for himself according to the Tata rule book.
He reportedly said he would challenge the move when the board told him that it had "legal opinion" in favour of its decision to remove him.
"The Tata board was well within its rights to remove Cyrus Mistry," Mohan Parasaran, one of three top lawyers consulted by the Tatas, told NDTV today, adding, "Tata board needed to be in majority to remove Cyrus which it was."
The lawyer said Mr Mistry was informed about his ouster just before the board meeting, when directors Ratan Tata and Nitin Nohria, who is Dean of the Harvard business school, held a private meeting with him to persuade Mr Mistry to step down.
Ratan Tata met top CEOs of the Tata Group at its famous Bombay House office in Mumbai today. He will be interim chairman and a committee that includes him has been given four months to find Mr Mistry's replacement.
At their 25-minute meeting Mr Tata told the CEOs that they should not worry about the changes in leadership, and must focus instead on business and making their companies market leaders.
He had assumed the role of interim chairman, Mr Tata said, for stability and continuity. "This will be for a short time. A new permanent leadership will be in place," said the 78-year-old, who was chairman for 21 years till 2012, when Cyrus Mistry took over.
The Shapoorji Pallonji group, which runs a construction business, owns nearly 18 per cent stake in Tata Sons and Mr Mistry continues to be a member on the board of directors of the company.
Ratan Tata Makes An Urgent Appeal, Seeks Blood Donor For Ailing Stray Dog In Mumbai Woman Posts About Taj Mahal Hotel's Canine Companion, Ratan Tata's Animal Love Story Sachin Tendulkar Meets Ratan Tata: "Conversations Like These Are Invaluable" Karnataka's 100% Quota Bill For Kannadigas In Private Firms For These Posts 13 Indians Among 16 Crew Members Missing After Oil Tanker Capsizes Off Oman Is Earth Orbiting Sun Or A Point In Space? Read This Fascinating Analysis 4 Top Leaders Quit Ajit Pawar's Party In Major Setback After Poll Drubbing Trump Shooting Conspiracy Theories Viewed 215 Million Times On X: Report Days After Rally Scare, Man With AK-47 Arrested Near Trump's Party Event Track Latest News Live on NDTV.com and get news updates from India and around the world.