BlackRock and Invesco have retained their positions as the leading institutional investors in AIM in terms of value, according to a report compiled by Growth Company Investor in association with Teathers. 

Institutional Investors in AIM 2008 found that BlackRock had £1.46 billion in 162 AIM companies, such as biometrics technology specialist RCG and investment bank Numis. Invesco was £488 million behind with £969.8 billion in 80 ventures on the market. 

But due to the tightening credit market BlackRock’s slice of AIM dropped from £1.66 billion during the same period last year with Invesco’s investments falling from £1.34 billion in 102 companies. 

The fortunes of BlackRock and Invesco are linked to the decline in AIM’s value during the past 12 months. Last year the market’s 1,688 companies were worth a total of some £119 billion, but by the end of August 2008 its 1,624 businesses had a combined market cap of £78.1 billion. 

In all, institutions own £39 billion worth of AIM shares, some 50 per cent of the market. That is an improvement on last year’s study that showed £55.2 billion, representing 46 per cent.