I am in receipt of KYC updating reminder for my father. He has passed away in 2013 and these the two letter where only FOLIO number is written and number of shares. How to know more details and get the same transferred on mothers demat account who is the legal heir too.
Write to Link or visit their Branch if in your city. They should be able to guide you with the procedure.
Search through your dad's old documents to see if there is any physical share certificate.
If the share certificate is lost; there will be some process [that link or the company who's shares you hold] will be able to guide you. Generally involves creating notarized document on stamp paper in prescribed format. This along with death certificate, etc should enable you to get the shares transferred to your mothers demat account