Misys shares leapt 7 per cent yesterday, after a third bidder threw its hat into the ring in the £1.2bn battle to buy the banking software firm.
Private-equity house CVC Capital Partners and ValueAct Capital, Misys' largest shareholder, are looking at a joint bid for the company.
The new twist comes just weeks after Misys started merger talks with Swiss rival Temenos. An announcement that the British firm's chief executive, Mike Lawrie, pictured, was quitting for another job seemed to confirm it would go ahead.
However, Misys then received a second approach, said to be worth £1.2bn, from US buyout group Vista Equity Partners.
Jeffrey Ubben, founder and chief executive of ValueAct, which originally backed the Temenos tie-up, said: "The proposed Misys and Temenos all-share merger has strategic logic, but we have decided to evaluate whether we can make an alternative proposal that provides the certainty of cash upon completion."
Last year Misys walked away from bid talks with Fidelity National Information Services, a US financial data company, over a deal thought to be worth £1.4bn.