The head of Eurex US has made at least $5m (€4.1m) from his holding in its arch-rival Chicago Mercantile Exchange, but he could have made treble that amount if he had not liquidated his stake over the past year.

Satish Nandapurkar joined Eurex US as chief executive in January last year to spearhead the Deutsche Börse-owned exchange's push into the US derivatives market. When he left, he held shares and options in the Chicago exchange that had a combined paper profit of $5m.