Hugh Osmond and Luke Johnson are both said to be mulling bids for Six Continents' retail pubs division, which will be demerged from the group's hotels in April.
The pubs division, which includes retail brands All Bar One, Ember Inns and Harvester, is set to be floated on the stock market under a new name for about £3bn.
Mr Osmond (pictured) and Mr Johnson, former university friends and business partners who fell out last year in the race for Whitbread's pub estate, are not acting in union.
But both entrepreneurs, who together built the Pizza Express chain, said they were "monitoring the situation" regarding the demerger and could launch bids if Six Continents investors signal their displeasure at the plans.
Press reports have suggested some large investors would welcome such a move. But the board of the group is thought to want £4bn against net operating assets of £3.4bn.
Neither are expected to make a decision on whether to proceed until Six Continents sends demerger listing details to shareholders in February.
A number of other groups are also said to be running the slide-rule across the estate. Venture capital groups CVC and Candover have both made approaches.
Spirit Group, the 1,000-strong managed business backed by Texas Pacific, was also said to be interested.
Six Continents recently unveiled full-year results. Operating profits in the "ongoing estate" were 5.1 per cent ahead at £288m on sales up 5.7 per cent to £1.475bn.
Average weekly pub sales are around £14,200, up three per cent.
The company made a point of saying it would focus 75 per cent of its capital investment on suburbia because the trouble high street market is over-supplied.
In the last year the most significant growth brands were Sizzling Pub Company, up from 23 sites to 96 and Ember Inns, which added 27 to take the estate to 137 outlets.