The mandate, which will take effect from February 1, is for some of the Tata group firms including Tata Consultancy Services, Tata Steel, Tata Chemicals, Indian Hotels, Tata Power, Tata Global Beverages and Titan, as well as Tata Sons and Tata Trusts, Adfactors said in a statement.
However, the new assignment to Adfactors does not include the account for Tata Motors.
The financial details of the mandate were not disclosed.
Prior to that, the mandate was with the Vaishnavi group of Niira Radia, who shut down her PR business after landing in a controversy triggered by the leak of her alleged taped conversations with various prominent people at the height of '2G scam'.
The Tata group has over 100 independent operating companies with presence in more than 100 countries. In 2016- 17, the revenue of Tata companies, taken together, was USD 100.39 billion with employee strength of over 6.95 lakh.
Founded in 1997, Adfactors is among the leading PR agencies in the country. It services over 300 clients, including large Indian and multinational corporations.