The reinstatement of Cyrus Mistry at the helm has once again left India’s $100 billion Tata group roiled by uncertainty.

Mistry’s possible return, after over three years, may now put the spotlight on N Chandrasekaran’s stint as chairman of Tata Sons, the group’s holding company. Chandrasekaran came in following Mistry’s October 2016 ouster in a board room coup. Yesterday (Dec. 18), an Indian tribunal for corporate disputes ruled that the move was illegal and “oppressive.”

The Tata group, in a statement, said it “strongly believes in the strength of its case and will seek legal recourse.” It has been given four weeks to appeal this ruling in the supreme court.

Shareholders are, however, concerned the work done by Chandrasekaran will now be undone. He was on the cusp of making key decisions involving the group’s major companies like Tata Motors and Tata Steel.

Here’s how some of them have performed on the bourses under his watch since Feb. 21, 2017.

Tata Consultancy Services

India’s largest software services company, which Chandrasekaran led before he took over at Tata Sons, has nearly doubled in market value to Rs8 lakh crore ($114 billion) since February 2017.

TCS accounts for over 70% of the Tata group’s overall market capitalisation and the software behemoth’s good fortunes have buoyed the valuation of the group as a whole.

However, it lost the “India’s most valuable company” crown to the Mukesh Ambani-led Reliance Industries (RIL) in September this year.

Titan

Shares of the $15 billion waches-to-jewellery retailer has risen over 150% under Chandrasekaran.

The company has also been diversifying. In February 2017, it launched the Taneira brand, which includes premium sarees and other ethnic wear. In May this year, Titan announced plans to expand its Taneira network, and double revenues from the brand.

Investors are upbeat on the prospects for Titan, which is now valued as much as the next two biggest Tata entities, Tata Motors and Tata Steel.

Tata Motors

The automobile major has seen a 60% erosion in market value, making it one of the worst-performing stocks under the incumbent chairman.

The company faced pressures from its bleeding British luxury unit Jaguar Land Rover (JLR). It posted a loss of Rs26,993 crore, one of the biggest in India’s corporate history, in the October-December 2018 period. This resulted in a sharp plunge by the Tata Motors’ scrip.

In the quarter, JLR was hit by slowing sales from the Chinese market, political uncertainty surrounding Brexit, and the growing demand for electric vehicles (EVs). However, in October, the Tata group chief dismissed plans to sell the unit it famously acquired from Ford in 2008. “Auto is a core business for us. From revenue terms, auto is our largest company,” he had said.

Chandrasekaran is now believed to be scouting for partners for JLR to jointly invest in EVs.

Domestic operations, too, have been hit by India’s economic slowdown. Except for the festival period in October, overal vehicle sales have slid in almost every month this year in India. In November, the figure was down 25% year-on-year for Tata Motors.

Tata Steel

Shares are down 10% since Chandrasekaran took over.

The company has been trimming its European operations following the downturn there. Tata Steel now plans to shut loss-making plants and cut 3,000 jobs as “stagnant EU steel demand and global overcapacity have been compounded by trade conflicts, which have turned the European market into a dumping ground for the world’s excess steel capacity,” it said last month.

Plans for a merger between Tata Steel and Germany’s Thyssenkrupp were blocked by the European Commission in June this year citing competition concerns. This was a blow to its revival plans.

Tata Power

The debt-laden company, and the ninth most valued Tata group firm, has seen shareholder wealth erode by nearly a third during Chandrasekaran’s stint. He has repeatedly stated that paring the power generator’s debt—over Rs48,000 crore as on March 31—is a priority.

A major overhang has been its loss-making Mundra coal-fired project in coastal Gujarat. The company has faced the vagaries of the price fluctuations of imported coal. Attempts to get state utilities to pay higher prices have been delayed, too, becoming a major drag on investor sentiment.