Haysmacintyre is preparing to fight a High Court damages claim for more than £200,000 after being accused of professional negligence over the valuation of a client in the corporate catering industry.

The legal battle centres on advice that the top 40 firm gave in 2002 to Jayne Billam, a former joint managing director at Artizian Catering Services, when valuing the shares of the caterer, whose clients include Hitachi Data Systems UK and HFC Bank.

Billam, who left the company in 2002, claims London-based Haysmacintyre negligently valued the company at £375,000 when it was actually worth £1,125,000 ­ well beyond any reasonable margin of error.

Billam, says that she sold her shares for £75,000 when their true value was £245,000 and lost the chance of selling to the remaining shareholders or an external buyer.

Haysmacintyre also failed to reflect its own valuation of Artizian shares of £1.19m less than a year before, the writ adds.

Haysmacintyre, which earnt revenues of £15.8m in 2007, said: ‘A former client has issued a claim against us in respect of a business valuation carried out in 2003. On advice from our solicitors and counsel we are defending our position vigorously and will continue to do so.’