Reports that three private-equity groups (Bridgepoint Development Capital, GCP and NBGI) have joined the running to buy the supplier of seeds and young plants have received no in-depth response from the firm.
Primary Capital, its owner, is reported to have hired Catalyst Corporate Finance to sound out interest. "We have no detailed comment," said Thompson & Morgan. "When a business has been owned by a private-equity investor for nine years, this kind of thing is par for the course."
Analysts estimated that the business, launched in an Ipswich baker's back garden 156 years ago, could be worth £25m.
Thompson & Morgan has a catalogue of more than 8,000 species and a mail-order business that supplies consumers in 144 countries.
Six years ago the firm, which produces own-brands for the RHS, Kew Gardens and the Eden Project, hired KPMG to find potential acquisitions, said to include Suttons.
"Under chief executive John May, Thompson & Morgan profits have risen 56 per cent a year, from £1.6m in 2008 to £3.9m in 2010," said business analyst Fast Track.
It added that Primary Capital holds 52 per cent of shares against 48 per cent held by management.