ONGC

OIL India Limited

Indian Oil Corporation

Gail

NTPC

Cairn Energy Indian Pvt Ltd

Naftogaz India Pvt.Ltd

Reliance Industries Limited

Reliance Natural Resources Ltd.

Adani Welspun Exploration Ltd.

Essar Oil

Instruments Research & Development Establishment

Laboratory of Electro –Optic System

Opto Electronics Factory

National Physical Laboratory

Hoya Lens Chennai