HSBC in India is preparing for an expected boom in the SME sector by targeting smaller businesses that have growth potential. Kala Rao reports from Mumbai.No customer is too small for HSBC, says Subir Mehra, who heads the bank’s small and medium-sized enterprise (SME) business in India. That is what prompted it to mine its retail banking customers in India, looking for small businesses that are poised to grow dramatically in a fast-expanding economy.