Sainsbury's shares surged 15.4% today after a report that private equity firms could launch bids worth more than £7 billion for Britain's second biggest supermarket chain.
Buyout groups including New York-based Apollo Global Management were circling Sainsbury's, the Sunday Times reported.
Sainsbury's, whose market value was about £6.9 billion at Friday's close, declined to comment.
The reported interest in Sainsbury's is the latest example of corporate America's voracious appetite for British companies across industries including retail, defence and healthcare.
Morrisons, Britain's fourth largest supermarket chain, is currently the target of a takeover battle involving at least two US groups.
The Sunday Times said Apollo's interest in Sainsbury's was exploratory and that the US firm remained in talks to join a consortium led by Fortress Investment Group in bidding for Morrisons.
"Sainsbury's is undeniably a good target for private equity with a considerable store estate, with the company having more than $10bn in property assets," Markets.com analyst Neil Wilson said.
"The supermarkets are generating the kind of yield that is hard to get elsewhere," he added.
Sainsbury's traces its roots back to 1869 when John James Sainsbury and his wife Mary Ann opened a shop in London's Drury Lane.
The company now has a 15% share of the UK grocery market, a distant second behind leader Tesco on 27%.
Qatar's sovereign wealth fund is the largest shareholder in Sainsbury's with almost 15% of the voting rights while Czech billionaire Daniel Kretinsky has a roughly 10% stake.
A bond investor who declined to be named told Reuters they had steered clear of buying Sainsbury's bonds last month because they believed it was likely to be a takeover target.
Private equity buyouts typically pay for acquisitions with debt that is then put on the target company's balance sheet - known as a leveraged buyout - which can hit the target's credit ratings and bond prices.
The bond investor said there had long been rumours of a Sainsbury's buyout but a deal could have more chance this year because the company is in a relatively defensive sector, offers reliable cash flow and owns many of its assets.
Shore Capital analysts said that if Apollo did not end up participating in any Morrisons deal, it and other bidders could go after Sainsbury's.
Apollo lost out last year on buying Asda, the third biggest British supermarket chain, to brothers Zuber and Mohsin Issa and TDR Capital. That deal valued Asda at £6.8 billion.