D. D. Thacker (1884–1961) better known was Diwan Bahadur D. D. Thacker, FRSA was a noted coal miner and philanthropist from Jharia, Dhanbad.
He was born in a Gujarati family in Bhuj in Princely State of Cutch and did his preliminary education there. He was attracted to coal mining business due to his connection with Mistris of Kutch, who had taken leadership in Jharia coal mining belt. He started his career in coal mining in 1905 and in partnership with Seth Khora Ramji & Brothers purchased Pure Jharia Colliery located in Jharia. After death of Seth Khora Ramji in 1923, however, he became sole proprietor of Pure Jharia Colliery, purchasing the stake from heirs of Khora Ramji. Later on he vigorously expanded his coal mining as well coal trading business and purchased several mines in Bengal & Bihar.
He was among the dignitaries, who shared dais in historic All India Trade Union Congress meeting held at Jharia in 1928 along with Ramjush Agarwalla, Karamshi Khora, Chhaganlal Karamshi Parekh and others.
He was first made Rao Bahadur by British in 1939 and later elevated to the title of Diwan Bahadur in 1942. He was noted for his research and development of coal mining technology and was a regular face in debate over various government policies in coal mines forums in early 20th century.
During his lifetime he held several posts like, Chairman and Secretary of the Indian Mining Federation, the President of The Geological, Mining and Metallurgical Society of India, Further, he also held post of Honorary First Class Magistrate of Jhaira He also served as President of the Bihar Chamber of Commerce, the Indian Colliery Owners' Association in his lifetime. He was among the patron and trustees of Jharia Anglo-Gujarati School.