An eleventh child born into a family business, Jain broke out on his own in real estate, starting as a broker and then developing land, initially in small towns but shifting focus to Delhi. His current projects now span 122 million square feet in 45 cities across India, including hotels, malls, IT parks and economic zones. He joined the billionaire ranks after his flagship company Parsvnath Developers listed on the stock exchange, of which he owns 80%.