A landmark case brought by the Office of Fair Trading (OFT) regarding the fees charged by banks for unauthorised overdrafts is set to hit the High Court later this week (16 January), with a host of top City firms lining up to oppose the competition authority.

The case will see the OFT take on seven banks and one building society in a bid to prove that the charges, which have affected thousands of customers, are illegal.

The case is one of the largest to hit the commercial court in recent years and will be heard by Mr Justice Andrew Smith in the International Dispute Resolution Centre on Fleet Street.

The hearing, which is expected to last for three weeks, will initially deal with preliminary issues of law as the OFT will try to prove that the Unfair Terms in Consumer Contracts Regulations introduced in 1999 apply to the overdraft charges.

A clutch of major UK law firms have bagged advisory roles on the case. Simmons & Simmons is advising Barclays, with Iain Milligan QC of 20 Essex Street instructed as counsel. Slaughter and May is advising Nationwide, alongside 3 Stone Buildings' Geoffrey Vos QC.

Addleshaw Goddard has been instructed by Clydesdale, with Richard Salter QC of 3 Verulam Buildings (3VB) instructed as counsel.

Ashurst is advising Abbey National alongside 3VB's Ali Malek QC, while Linklaters and One Essex Court's Laurence Rabinowitz QC advising the Royal Bank of Scotland.

Freshfields Bruckhaus Deringer and Erskine Chambers' Richard Snowden QC are advising HSBC, with Lloyds TSB turning to Lovells and Fountain Court's Bankim Thanki QC.

The banks are thought to have each spent approximately £1m in pre-trial costs.

The OFT has instructed Fountain Court Chambers' Brian Doctor QC.

Lovells litigation partner Andrea Monks, who is advising Lloyds TSB, commented: "This is a great case to be working on. It will potentially be one of the most significant banking litigation cases of the year so it is good to be involved."

There has been substantial speculation over the outcome of the case, with some lawyers claiming that a victory for the OFT would have a dramatic effect on the banking industry. Many predict the closely-watched case will be appealed due to its significance and will most likely go all the way to the House of Lords.

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