A few days ago, Jignesh Shah of the Financial Technologies group personally congratulated Ashish Chauhan on his appointment as CEO and managing director of the Bombay Stock Exchange (BSE) when they met at a conference at Trident hotel in Mumbai. The significance of this gesture lies in the unstated tension between BSE and Shah’s Multi Commodity Exchange (MCX). In a recent interview to a financial daily, Shah accused an exchange of misrepresenting facts about the securities transaction tax (STT). He was probably hinting at BSE because Chauhan had at a public function in October said the lack of STT on commodity trading was shifting trading volumes to that segment. The large volumes on the MCX platform are through arbitrageurs who benefit from lack of transaction tax. On the other hand, STT has been a key catalyst for driving down equity cash market volumes, which affected BSE the most. Shah probably wants to cultivate Chauhan in his long-drawn battle with the National Stock Exchange, but Chauhan’s reasons are not that easy to read.