New Delhi, May 2 -- As markets whipsawed from February's depths to March's resurgence, India's mightiest business empires-from Tata to Birla faced a high-stakes showdown. While the Nifty 50 clawed back to flat (by the fiscal year end), aMint analysis of the country's leading business houses-Tata, Reliance, Adani, Rahul Bajaj, and Aditya Birla-with a fifth of India's market capitalization, unveiled a striking divergence: overseas and small investors retreated, while local institutional investors doubled down on select bets, hinting at a fascinating long-term focus.

India's most valuable conglomerate, the Rs.27.5 trillion Tata group, saw a dramatic reshuffle in its investor ownership. Foreign portfolio investors (FPIs) and retail sharehold...