Tata Sons Chairman Natarajan Chandrasekaran on Wednesday announced his resignation from the post. In February 2017, he became the seventh Chairman of Tata Sons. Before him, Cyrus Mistry, Ratan Tata, Jehangir Ratanji Dadabhoy Tata (JRD Tata), Nowroji Saklatvala, Dorabji Tata and Jamsetji Tata had held the post over the Tata Group's 158-year history.