Undeterred by India's slowing economy, Kumar Birla's $40 billion (sales) commodities conglomerate Aditya Birla Group is continuing to expand at home. In September, its cement arm UltraTech inked a $600 million deal to buy a rival unit; the combined group is now country's largest cement producer. In October he was named by the Central Bureau of Investigation in a CASE linked to the IMPROPER allocation of coal mines to his aluminum maker Hindalco in 2005. He denied the allegation, calling the charge "preposterous." Prime Minister Manmohan Singh backed Birla, saying he had approved the allocation.