Potential buyers for the business -- which is being sold by U.S. investment bank Goldman Sachs (GS.N: Quote , Profile , Research ) -- include US private-equity giant Kohlberg Kravis Roberts, Candover, CVC Capital Partners, and The Blackstone Group, which is bidding in partnership with a small healthcare specialist.

Alchemy and Goldman Sachs declined to comment on the sale, which is expected to attract bids of at least 750 million pounds ($1.33 billion), according to the sources.

Four Seasons includes over 400 nursing homes, with around 18,000 beds, and is a prime candidate for private equity firms looking for steady revenues.

"First-round bids went in last week," said a source close to one of the bidders.

The source added that Alchemy intends to shortlist second-round bidders within the next few weeks or so.

Another source said the sale would likely be a lengthy process, given the level of interest expressed so far.

"We're talking months rather than weeks," the source said, adding that a sale could be wrapped up by July.

Four Seasons was founded by Alchemy in 1999 when it acquired two separate companies, CrestaCare and Four Seasons Health Care, for about 133 million pounds, which included about 44.5 million pounds in cash.

Since then, Alchemy has grown the business through acquisitions, buying two more health groups in 2002.

According to Alchemy's web site, Four Seasons is expected to have revenues of around 350 million pounds in 2004 and earnings before interest, taxes, depreciation and amortisation of about 80 million pounds.