That is one conclusion of the research into the top 728 scientific and lab equipment companies in the UK - 434 of which currently remain in private hands. There are a number of reasons that are causing this number to dwindle though: these include exclusivity, niche products, unique services, and more practically, ageing management.

"The increasing age of owners and principals at some of these companies is causing them to consider their choices," said David Pattison, senior analyst at Plimsoll.

"While many family firms have succession plans in place, an offer for the company at the crucial moment is often listened to sympathetically, as the new generation review their options."

Other public companies might be attracted by the hidden potential of some private companies; current owners typically strip out 80 per cent of profit as fees, according to Plimsoll, and to the value hunter, this is a "huge platform on which to build."

While many may wish to sell the family business, this changing atmosphere in the industry does bring potential pitfalls to the fore. Plimsoll notes that fewer family companies might lead to a loss in the "steady corporate stewardship and entrepreneurial drive that has been a cornerstone of the economy for the last 60 years."

However, the report also acknowledges that new professional owners might also offer greater drive and focus, even if they also bring the burdens of increased debt and risk.

If a company does decide to sell up, the report warns that owners of private companies often haven't sold themselves well enough in the past.

"The problem for private companies wishing to sell is that many of them haven't done themselves any favours in the past in terms of promoting the value of the business," said Pattison.

"With the help of professional advisers, they have become very adept at hiding their worth. When they go to sell, there simply isn't the evidence to support a high asking price. Potential buyers will always make a low offer in this situation because they simply won't believe a company's own unsupported figures."

It is exactly this uncertainty that must be addressed if both potential sellers and buyers are to get their money's worth in prospective takeovers.