At pounds 40bn of funds under management, this previously British company is less than half MAM's size, but no small player either. Yet the reason for the sale was given as the globalisation of the fund management industry. It seems in the view of the owners, LGT was too small to survive by itself.
In a comparatively short space of time a large number of seemingly impregnable British financial institutions have fallen to foreign predators - all in the cause of globalisation.
Warburgs is now part of Swiss Bank Corporation, Kleinworts of Dresdner Bank. Morgan Grenfell fell to Deutsche Bank some years back, but perhaps that just shows the prescience of Germany's leading bank.
The deals have come thick and fast recently. The acquisition of BA Financial Services, which includes such household names as Allied Dunbar and Eagle Star in the UK, by Swiss insurance giant Zurich, has also created a major multinational fund management force.
It seems these days that big really is beautiful.
Naturally enough, speculation is now rife on who will be the next to fall. The trouble is that most of the players in the UK are simply not big enough to interest the likes of the major US houses. The MAM deal puts Merrill firmly in the No 2 position in the world, behind Fidelity of America.
Consolidation in the US has been taking place already and some domestic companies, such as Invesco, the fund management group that has its origins in the old Slater Walker investment banking business, have turned their attentions to the other side of the Atlantic as the only way of achieving the size that many perceive now to be necessary to win the major institutional mandates that are so highly sought after.
The investment clout that these institutional funds provide can allow the development of retail products, which both adds to and benefits from the public perception of the fund management operation. And it does no harm to have your most senior fired manager dubbed the most powerful woman in Britain either.
In practice it is very difficult to spot the next takeover victim. Few would have expected MAM to be a willing target - but this is an agreed bid from America's most powerful brokerage house.
Fund management is, after all, a people business. The assets Merrill Lynch are buying are principally individuals, people well skilled in winning and retaining investment portfolios.
Make a mess of managing a business like that and your expensively acquired assets walk out the door. There are always many willing to recruit, not least being Nicola Horlick, who was herself once at Mercury.
If investment attention is firmly focused on domestic players in investment management, it can only be because the Far East is being studiously ignored by managers in London at present.
If it had not been for the US brokers' largesse in London, I would have been writing about Japan.
The market there has been plunging up and down in a fashion that should be a comedy writer's delight. First economic measures are badly received, then a bank goes bust - and shares rise.
Then worries filter through that the authorities might just bail out the beleaguered financial sector - leading to a sharp downward correction. And, of course, in the end buyers start bargain hunting - up we go again.
Except, of course, it is not really the end. What the final act will usher in for the market that was once bigger even than Wall Street is hard to gauge.
Most foreign investors are sitting on the sidelines, either having withdrawn from an investment area where damage has been meted out on both the currency and share front, or wishing fervently that they had the foresightedness to have withdrawn, as Templeton did back in the late 1980s.
Deregulation looks more of a reality now, but the financial sector, and the economy for that matter, is in a mess.
Just over the sea, another major local economy is also suffering from the aftershocks that have travelled around the region.
Korea is fortunately trying to tough it out. Quite whether the IMF would be able to bail out an economy that is comprehensively bigger than most of the other so-called Tigers in the region put together is a moot point.
In the meantime it looks a "won-way" ticket to nowhere.
Brian Tora is chairman of the Investment Strategy Committee of stockbrokers Greig Middleton.