Investors in Perth-based mining group MACA are becoming more outspoken about their opposition to a takeover bid from Thiess, citing lack of clarity on dividends and the rising value of listed contractors as reasons for not accepting a $367 million offer.

Ellis Zilka, who owns tens of thousands of MACA shares through a trust and started buying stock eight years ago, said he wants the board of the mining services group to confirm whether they will pay investors a dividend if Thiess’ offer does not succeed.