Specsavers, the high street optician, is heading for a court showdown with Asda in a row over copycat advertising.

The Guernsey-based retailer has accused the supermarket giant of infringing its trademarks in an advertising campaign for eyeglasses launched online and in more than 80 supermarkets last month.

It claims that the slogan used by Asda — “Be a real spec saver at Asda” — is designed to mislead customers and harm its business. It also objects to the use of a logo with two ellipses similar to Specsavers’ logo.

Specsavers won the first round of the legal battle on Tuesday after a judge agreed to treat the case urgently and scheduled a full trial for April. Mr Justice Kitchin, sitting in the High Court in London, ruled that there was sufficient evidence to believe that Asda’s campaign could threaten Specsavers’ reputation to bring the trial forward.

However, although he agreed to expedite the date, Mr Justice Kitchin said the trial could take place on April 13 at the earliest. Specsavers’ had argued that it should be held as early as January.

In an unusual twist, Asda’s barrister succeeded in pushing back the expedited date on the grounds that the company’s lawyers needed additional time to prepare their defence because they will be stacking supermarket shelves over Christmas.

Lawyers from Pinsent Masons, the City solicitors, have agreed to work for Asda free of charge for three days during the Christmas period in order to understand its business better. Specsavers’ barrister ridiculed the prospect of Asda’s lawyers stacking shelves, to which Hugh Cuddigan, Asda’s counsel, responded: “M’learned friend may pour scorn on the policy of having executives working on the shop floor but that is how it does work.”

Mr Cuddigan said that a later trial date was also necessary because its lawyers planned to conduct a wide-ranging survey of Asda shoppers to determine whether they had been misled by its advertising.

Asda launched a price war last month when it began selling single vision glasses for a flat rate of £50 and designer glasses for £70 regardless of the strength of a customer’s prescription. It accused other retailers of deceiving customers by advertising eyeglasses for as little as £25 when variations in prescriptions could push the price of some pairs as high as £200.

Asda plans to stop using its “Be a better spec saver” slogan after this week, in keeping with its marketing strategy, the court heard, but will continue using the “elliptical lozenges” logo in its stores and on its website despite Specsavers’ complaints.

In a statement to The Times, Asda said: “We're simply putting an end to unfair prices and giving all our customers no-nonsense low prices they can trust, whatever their prescription — no nasty surprises, no hidden extras.”

Richard Holmes, Specsavers’ marketing director, said it was pleased that the judge had agreed to an expedited trial.

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