Mr Mazumdar is the Chairman of TIL Ltd, Calcutta, and also its Myanmar subsidiary, Myanmar Tractors & Trading Co. Ltd. He is on the boards of several leading Indian multinational companies, the Export Import Bank and leading management institutes. He was past President of two Apex Chambers of Commerce in India, past Chairman ICC India, has been a member of ICC's Executive Board and was Chairman of ICC's World Chambers Federation from 1997-2005.

TIL Ltd is engaged in the manufacture, sale and servicing of earthmoving, construction, mining, material handling, power generation, oil field, and chemical process equipment. TIL has four manufacturing plants in Calcutta, Delhi, Mumbai and Pondichery, and over 40 sales and service outlets throughout India. It has a close association with Caterpillar, USA (55 years) and Grove Worldwide (52 years).