London's Alternative Investment Market has finished its busiest quarter on record, admitting 144 companies between April and June. The boom came just ahead of the introduction of new, prescriptive measures set out in the European Union prospectus directive on July 1.

The number of companies listing in the quarter was up 90% from the same period last year, and up from 125 in the three months from January to March, according to financial adviser Grant Thornton.