Indian billionaire Gautam Adani's property unit has formed a joint venture with Mumbai's slum rehabilitation authority to redevelop the Dharavi, one of Asia's largest slums. The formation of the entity, Dharavi Redevelopment Project Pvt Ltd, is a critical step as Adani faces a legal challenge from a rival bidder, SecLink Technologies Corporation. The next step will be the submission of a master plan by the Adani group, which won the Dharavi rebuilding project in July for $610 million.