Top UK law firms stand poised for a flurry of panel activity as two of Europe's most coveted clients launch reviews of their advisers.

FTSE 100 energy company National Grid is set to overhaul its roster of external advisers for the first time in three years, while US investment banking giant Lehman Brothers is holding a review of its fee arrangements with outside counsel.

Speaking at Sweet & Maxwell's general counsel forum in London last week, National Grid general counsel Helen Mahy said that she was looking to open a review of the company's commercial advisers to both existing panel members and new firms.

Firms currently on the energy giant's commercial panel for its UK electricity, gas and infrastructure business are Hammonds, Eversheds and Pinsent Masons.

National Grid last reviewed the commercial panel in 2004 following Mahy's appointment as general counsel. The review will not affect the company's lead corporate advisers – CMS Cameron McKenna and Linklaters.

Meanwhile, investment bank Lehman has launched a cost review of its panel arrangements, pushing for better value for money from firms in response to rising fee rates.

Firms believed to be affected by the review include Allen & Overy, Ashurst, Lovells and Weil Gotshal & Manges, as well as Freshfields Bruckhaus Deringer, Herbert Smith and Linklaters, which have established links with the bank.

It is understood the review has been driven by Lehman's procurement arm in response to the current market downturn and the bank's drive to control costs. The US bank reported a $700m (£339m) loss at the beginning of September as a result of the recent market turmoil.

One partner at a panel firm said: "They are reviewing how the panel works and refreshing it. This exercise looks at cost savings across the board – abort fees in particular will be looked at."

The move comes just a year after Lehman last reviewed its UK panel, appointing six new firms to its list of core advisers and creating three specialist sub-panels for real estate, fixed income and investment banking work.

The news follows recent research which found a number of clients consolidating their advisers. The report by Legal Week Intelligence found the average number of advisers on panels has fallen from seven to less than five in the last year. The report also found panels are being enforced more rigorously, with three-quarters of clients reviewing their panels every two years.

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