The Government has changed the rules to allow investors to hold shares listed on the Alternative Investment Market (AIM) in their ISAs. Stockbrokers saw a lot of transfers of shares by investors, mainly in popular but speculative companies, from their taxable dealing accounts into their tax-exempt ISA accounts when the change took effect on August 5th. But experts warned that many AIM shares were very risky and the best way to invest in smaller companies of this type was through a managed fund.