The Gazette revealed this week that law firms are already getting well into discussions with external investors in readiness for when the rules change in October 2011, and indeed some are even going as far as to enter into ‘gentlemen’s agreements’ with funders to exchange loans for an equity stake once the rules permit it.

But while it seems quite a few firms are actually engaging in these discussions, none of them are exactly broadcasting that they are doing so, for obvious reasons. If you were gearing up to get yourself a nice little million pound war chest with which to go out and grab some of the top teams from your rival firms, you wouldn’t exactly want anyone to know about it in advance.

But it creates a funny kind of atmosphere. No firm is exactly sure what their competitors are going to do come October 2011. Are they going to take the external buck, and if so, how much, and how are they going to use that cash?

Firms that are being active in their arrangements – or as active as the rules permit – probably have a fair idea that others are doing the same.

But some of those that are not seeking outside capital themselves are – I am told – simply assuming that no one else in their market is either. They won’t think the changes affect them until they realise someone has just waved a big wad of cash under the noses of some of their highest fee-earning lawyers, and the whole team has just walked out of the door, Pied Piper-style.

It is not just the commoditised fields of personal injury and conveyancing that will be affected by the ownership and investment new rules, though of course they will. These sectors of the profession are only too aware of the prospect of big brands entering their markets.

But City firms are also likely to be taking advantage of the opportunities. A large firm with a £60-100m turnover could easily raise enough to buy another practice by selling a minority stake – though if it is not giving away a controlling interest it will have to persuade venture capitalists that it is running a very tight ship.

But even at the smaller end, a £10m turnover firm might convince a business angel or private investor to part with half a million to scoop up some talent from competitors in return for a minority equity share.

Even at the very top of the tree, the magic circle could be tempted by the huge cash injection that could be gained from, say, a flotation on the stock exchange. What for, you may wonder – they are already too big to need any serious expansion.

But when you look at law firms globally, there is probably no single firm that has a global market share of much more than 1%. Compare that to the Big Four accountants, where the likes of PricewaterhouseCoopers have – I would guess – around a 25% share, and you begin to see the potential.

True, law firms have more obstacles to global expansion than accountants because of local bar rules, but still. It doesn’t matter what sector of private practice you’re in, the chances are the new rules on external investment are going to affect you somehow, good or bad.