Mumbai: Markets regulator Sebi on Friday proposed to hike the minimum amount for a large chunk of shares to qualify as a block deal, from Rs 10 crore now to Rs 25 crore. Block deals are executed through special 15-minute trading windows on stock exchanges twice a day and at prices that are fixed by a regulator-mandated formula.“The minimum order size for execution of trades in the block deal windows shall be Rs 25 crore. Every trade executed in the block deal windows must result in delivery and shall not be squared off or reversed,” the draft circular said. “The stock exchanges shall disseminate the information on block deals such as the name of the scrip, name of the client, quantity of shares bought/sold, traded price, etc. to the general public on the same day, after market hours.“The morning block deal window will be open from 8.45 am to 9 am, with closing price of the previous day as reference price, while the afternoon window will be open from 2.05 pm to 2.20 pm, with reference price as volume-weighted stock price traded between 1.30 pm and 2 pm the same day.