Luckily for those compiling these lists, when the information is not forthcoming, they don't need to be based on too much fact or even reason. Rather, they are usually a result of a bit of imaginative thinking.
Throwing in a major company like Amec never hurts, nor does suggesting an acquisitive European giant such as Vinci or Skanska. Inevitably most of these tips are wildly off the mark and sink without a trace.
But sometimes the lists, which are usually accompanied by the phrases "ready to pounce", "waiting in the wings" and "white knight", are on the button. Think JA Jones and Balfour Beatty or Wimpey and Laing Homes.
Amey and Atkins, construction's two major basket cases this year, have both been widely tipped to be taken over as a result of their well-documented problems.
The latest rumours doing the rounds are that Bouygues and Skanska are looking at both firms and Vinci is also said to be interested in Amey.
Now try this one: Atkins to merge with Jarvis. Watch this space.