Murray & Roberts increased its offer to buy out Concor minority shareholders substantially on Wednesday in the latest twist to the bid that appeared to be in the bag a few months ago.
SA's second-largest construction group said it had upped its R22,30 a share offer for the smaller rival to R28 a share after considering "changed circumstances in the investment market".
Concors share was trading at R26,04 on the JSE on Wednesday.
Voting on the deal was delayed earlier this month after it emerged that Rand Merchant Bank's (RMB) asset management division bought a 9% stake in Concor and said it would vote against the deal.
The move had raised Murray & Roberts' ire, as another division of the bank had been its lead sponsor on the deal.
RMB corporate finance division resigned as lead sponsor shortly afterwards.
The deal appeared to be close to conclusion in September.
This was after entities holding about 60% of the Concor's shares pledged support for Murray & Roberts' initial offer.
The deal forms part of Murray & Roberts' efforts to grow revenue.