The next point follows as a logical corollary. Handle your Delivery Instruction Slips (DIS) Book issued by the DP very carefully. Insist that the DIS numbers are pre-printed and your account number (client id) is also pre-stamped on each DIS page. Don’t use and don’t accept loose leafs from your DP. Don’t leave signed DIS slips with your broker, DP, sub broker and above all, make it a point to keep it in a secure and safe place.
Some dos you need to remember when you fill up the DIS. Always mention the details like ISIN, number of securities accurately. If in doubt, contact DP or your broker immediately. The broker may ask you for a power of attorney to simplify the Demat process. While that is convenient, there is no onus on you to accept that arrangement.