Client code modification reporting: exchanges must submit monthly statements detailing modified client identifiers and transaction particulars. Stock exchanges must furnish a monthly Form No.3BB reporting transactions where client codes were modified after registration, identifying the exchange and PAN and attaching a soft copy annexure that itemises derivative and cash market entries with transaction ID, broker, original and modified client codes, names and PANs, scrip, quantity, rate, total value, buy/sell indicator and transaction date, and must include verification by the principal officer certifying correctness and completeness.