If you do not wish to avail CAS facility do write to us as per comm no:4816 , 4900. Prevent Unauthorised transactions in your account --> Update your mobile numbers/email IDs with your Stock Brokers. Receive information of your transactions directly from the exchange on your mobile/email id at the end of the day. Issued in the interest of investors.Prevent Unauthorized Transactions in your demat account --> Update your Mobile Number with your Depository Participant. Receive alerts on your Registered Mobile for all debit and other important transactions in your demat account directly from NSDL/CDSL on the same day......................issued in the interest of investors.With effect from 01-01-2016 no need to issue cheque by investors while subscribing to IPO. Just write the bank account no. and sign in the application form to authorise your bank to make payment in case of allottment. No worries for refund as the money remains in the investor's account.No need to issue cheques by investors while subscribing to IPO. Just write the bank account number and sign in the application form to authorise your bank to make payment in case of allotment. No worries for refund as the money remains in investor's account.