Norton Rose and DLA Piper continue to boast the broadest base of clients listed on London's Alternative Investment Market (AIM), with the duo topping new quarterly client rankings released this week.

Norton Rose maintained its position of advising more AIM-listed clients than its UK rivals, with the top 10 City firm holding a client base of 65 businesses, according to Hemscott statistics.

The figures – which are taken from deals during the period from the beginning of October to the beginning of January – rank DLA Piper in second place, closing the gap on Norton Rose by gaining four clients over the quarter to bring the firm to 59 in total.

Pinsent Masons is ranked third with 53 clients on London's junior market, the only other law firm to advise more than 50 listed clients. Berwin Leighton Paisner comes in fourth with 49.

Norton Rose corporate partner Mark Lloyd Williams (pictured left) commented: "We concentrate on acting for growth markets, so these tables reflect what we do. However, the market in the last quarter has been less interesting in terms of deals – 80% of the listings we have done in the last year took place in the first six months."

In the last quarter, Norton Rose acted for Arden Partners on the AIM initial public offering (IPO) of renewable energy company Greenko Group, as well as advising AIM-listed mining company Aricom on its introduction to London's main exchange.

Favourable tax conditions place Isle of Man-based Cains in a leading position by FTSE AIM 100 clients, tying with Norton Rose with eight clients apiece, while LG takes third place with five clients.

Travers Smith enters the tables for the first time, acting as adviser to four of the top 100 AIM clients. Having not previously held any clients in the top 100, the firm now takes equal fourth place alongside Ashurst, Carey Olsen, DLA Piper, Macfarlanes, Pinsent Masons and Taylor Wessing.

Travers head of corporate finance Spencer Summerfield (pictured right) said: "During the past two to three years we have been focusing on building up the number of listed clients we act for. The easiest way to do that is a push towards acting for companies doing IPOs."

At the end of last year Travers acted for new client Juridica Investments, when it became the first third-party litigation fund to list on AIM following its £78.4m IPO.

Ranked by market capitalisation, LG tops the tables with clients worth a total of £7.6bn, with Norton Rose coming in second with a combined client base worth £6.5bn.

The statistics also demonstrate the growing attention being paid to the City's junior market by larger law firms, with Freshfields Bruckhaus Deringer and Linklaters both taking a place in the table of FTSE AIM 100 clients ranked by market cap. Freshfields has climbed to sixth place from 11th, advising businesses worth a combined value of £1.9bn, followed by Linklaters in seventh place as adviser to £1.7bn worth of listed clients.

The rankings come as the impact of the credit crunch has caused much of London's IPO market to dry up, with many listings being delayed and several aborted altogether.

Pinsents head of corporate Gareth Edwards said: "The lead time on floats meant that a number were already underway at the beginning of the quarter when the credit crunch hit, so for the most part they got away, although maybe not as well as they would have done otherwise.

"The real trouble hit in the run-up to Christmas, when things really got tough."

Lloyd Williams added: "The normally busy run-up to Christmas was distinctly quiet. Some deals are boldly going on, but a lot have pulled out – particularly in the last two or three weeks."

The figures come as Olswang this week moved to improve its AIM credentials with the hire of respected AIM expert Max Audley from Faegre & Benson, where he led the London corporate practice. Audley sits on the London Stock Exchange's AIM advisory group.

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