Dematerialisation requirement: securities must be credited and issued in demat form, with separate accounts provided where needed. Listed entities must comply with Rule 19(3) of the Securities Contract (Regulations) Rules, 1957 for allotment/transfer-related advices. Securities arising from investor service requests for subdivision, split, consolidation, renewal, exchanges or issuance of duplicates on account of loss or worn-out certificates must be credited in dematerialised form within thirty days of receipt of request and documents. Securities under a Scheme of Arrangement or any sub-division, split or consolidation are to be issued only in dematerialised form, with a separate demat account opened for investors lacking one. Schedule VI procedures apply to unclaimed or escrowed issue securities.