Healius Limited (ASX:HLS) have soared 8.3% after Australian Clinical Labs Limited (ASX:ACL) put forward a nil premium merger proposal for the business, but most in the market believe it will have to put more money on the table to get the $2.4 billion-plus tie-up over the line. Most see the offer as opportunistic, arguing that the target needs some sort of compensation for the $95 million of cost synergies that the Goldman Sachs-advised ACL claims it will achieve, and Healius told shareholders to take no action. But shareholders like the idea of a deal, as shown by the share price movements, and there has been pressure from investors on the Healius board to embark on a sale, as they grow frustrated about its lacklustre performance.

ACL has been managed well, and some believe its performance is as good as it gets, whereas Healius has a lot more upside under the right leadership. This could be more of a reason why ACL should pay more, although people say it makes sense to bring the two companies together.