The news overshadowed a warning from Mouchel that trading conditions remained challenging and it may need fresh funds if it fails to reach a refinancing deal with its banks.
Analysts said a price of around 100 pence per share, versus Friday's close of 56.5 pence, would make a good starting point for any offer.
Shares in Mouchel were up 33 per cent at one stage.
"I have got a target price of 105 pence, somewhere near a pound would be a sensible start point," Panmure Gordon analyst Andy Brown, who has a 'buy' rating on the stock said.
Brewin Dolphin analysts suggested a "potential exit price of over 110 pence."
Mouchel, whose operations range from highway maintenance to consulting for local authorities, has been hit hard by government cutbacks and last week confirmed it had ordered a review of the business.
Even after Monday's leap its shares are still 70 percent lower than at the start of this year when they were trading at around 260 pence.
The company said the approaches did not reflect its value, adding it was preparing the possible sale of non-core businesses and was "already aware of interests" in them.
"The announcement this morning from Mouchel takes shareholders in conflicting directions in our view, but the most eye-catching news is the fact that the company has received approaches," Arbuthnot analyst Nick Spoliar said in a research note.
Negotiations about refinancing banking facilities are going as planned, the company said, repeating that it expected to agree new facilities by March.
"We are not however complacent about this and are therefore simultaneously exploring alternative funding strategies," the company said, adding that it had started preparatory work on the possible sale of non-core businesses and an equity fundraising."