Dematerialisation requirement: exchanges may shift securities from trade-for-trade to rolling settlement upon demat and certification conditions. Securities of companies that have established connectivity with both depositories may be shifted from Trade for Trade Settlement to Rolling Settlement if at least fifty percent of other-than-promoter holdings are dematerialised, supported by a certificate from the Registrar and Transfer Agent or, where no separate RTA exists, from a practising company secretary or chartered accountant, and if there are no other grounds for continuing Trade for Trade Settlement; stock exchanges must report actions in their monthly or quarterly development reports.