Waste collection company, Biffa, has agreed to a £1.2bn ($2.3bn) takeover offer from a group of investors.
Biffa was spun off from water company Severn Trent in 2006
A consortium including the private equity firm Montagu Funds is offering 350 pence per share.
Biffa said another group is considering making an offer, and that this potential approach might be worth more.
Biffa, which was spun off from water company Severn Trent in 2006, collects waste for more than one million households in the UK.
Montagu has past experience in the waste business, as it once owned Cory Environmental which has landfill sites and local government contracts.
Montagu director, Jason Gatenby, said Biffa was "a market leading business with a great workforce in a sector we understand well and where we have a demonstrable track record of success".
But analysts say another bidder could emerge.
Seymour Pierce analyst, Kevin Lapwood said: "There are still several infrastructure investors that would pay more and we still believe that a price closer to 400p is more realistic."
Biffa has 33 landfill sites and 42 treatment and recycling centres.
Last year it had operating profits of £90.7m on sales of £742.7m.