New Delhi, Aug. 14 -- Tata family members and a handful of senior executives, including Tata Steel Ltd.'s Thachat Viswanath Narendran, are emerging as contenders to lead the 158-year-old conglomerate, according to people familiar with the matter.

The search began after Natarajan Chandrasekaran said he would step down as chairman of Tata Sons Pvt. when his term ends in February 2027, setting off an unexpected leadership transition at a group that is a household name across India.

Besides Narendran, chief executive officers of group companies such as Tata Power Co.'s Praveer Sinha, Tata Motors Passenger Vehicles Ltd.'s Shailesh Chandra and Tata Chemicals Ltd.'s Ramakrishnan Mukundan are in the early list, said the people, asking not to be...