Kotak will purchase the stake from bourse operator Financial Technologies (India)(FTIL) and the deal is subject to regulatory approvals, the statement said.
MCX shares were trading up 8.25 per cent to 851.40 at 09:44 a.m.
Financial Technologies had announced on Saturday that it has entered into a Share Purchase Agreement (SPA) to sell its 15 per cent stake in Multi Commodity Exchange of India Ltd to Kotak Mahindra Bank for Rs 459 crore.
FTIL, which has to bring down its stake to 2 per cent in MCX following the order from the regulator Forward Market Commission (FMC), had offloaded 4 per cent stake in the commodity exchange on July 16.
In December, FMC had declared FTIL as unfit to run any exchange after a Rs 5,600 crore payment crisis at group company National Spot Exchange Ltd (NSEL).
The regulator asked FTIL to reduce its stake in MCX to 2 per cent from 26 per cent.