Decision expected this week
Deutsche Boerse is mulling cutting the vote threshold needed for getting its £20bn merger with the London Stock Exchange approved.
The German exchange needs the support of 75 per cent of shareholders to win approval.
Last week, LSE Group said 99.89 per cent of its voting shareholders had supported the deal.
Currently, index funds hold up to 15 per cent of Deutsche Boerse shares but are only capable of tendering these shares after the threshold has been reached.
A statement from Deutsche Boerse said: “The parties involved are currently evaluating a potential lowering of such minimum acceptance threshold with a view to enable index funds to participate in the offer.”
If the merger goes through, the tie-up will create the world’s biggest exchange by revenue, forecast to be €4.7bn ($5.19bn) this year.