In the Nifty 50, the most tracked index by passive funds, the group's combined weight declined to 7.6 per cent in August 2026 from 8.3 per cent in August 2025.

The group’s weight is currently at levels last seen in 2020 despite more Tata group companies entering the index. Tata Consumer Products and Trent were added to the Nifty 50 in 2021 and 2024, respectively, while TCS, Titan, Tata Steel and Tata Motors have been constituents for several years.

The recent decline has been driven largely by TCS, whose shares, along with those of other information technology (IT) services companies, have fallen sharply in calendar year 2026. A slowdown in earnings growth, weak guidance and uncertainty around the impact of artificial intelligence (AI) have weighed on investor sentiment. Foreign institutional investor (FII) selling in Indian large-cap companies has also pressured the stock.

If the Tata Sons listing takes place, it would add another large-cap group company to the listed space. According to reports, the listing could take place at a valuation of up to ₹12 trillion, based on an estimated value of ₹15-16 trillion for its underlying portfolio. More conservative estimates, which factor in a holding company discount, put the potential listed valuation below ₹10 trillion.

At a valuation of around ₹10 trillion, Tata Sons would rank among India’s 10 largest listed companies and could qualify for inclusion in key indices such as the Nifty 50, Sensex and the Nifty 100.

Tata group's collective market capitalisation (m-cap) stood at ₹25.80 trillion in September 2026, or 9.73 per cent of the Nifty 100’s ₹265.06 trillion, its lowest share in at least five years, hinting that a listing boost could up its market value.

The group’s value is down from 9.93 per cent (₹26.99 trillion of ₹271.86 trillion) in 2025, and well off the 12.60 per cent (₹22.06 trillion of ₹175.03 trillion) peak in 2021. Over the past five years, the group’s Nifty 100 weight has ranged between 9.73 per cent and 12.60 per cent. A potential Tata Sons listing could unlock holding company value and add fresh equity to market float.