Diageo reportedly believes that its intellectual property has been infringed by "Pitcher", Sainsbury's own brand alcoholic beverage which, like Pimm's, can be mixed with lemonade and fruit and, according to Diageo, has a similar bottle, label and logo to Pimm's.

This case comes hot on the heels of the landmark trade mark ruling by the European Court of Justice on copycat products, L'Oreal v Bellure. That case related to imitation perfumes, which were clearly not copies of trade marked goods but which were marketed in such a way as to "wink at" L'Oreal's famous perfumes.

Whilst the reasons for the L'Oreal ruling are not at all clear to the legal community, the effect of the L'Oreal case was to hold that unlawful "unfair advantage" could be taken of a famous brand, even where no confusion or detriment to an existing trade mark occurred. The judgement states that a famous registered trade mark could still be infringed if use of a similar sign seeks to "ride on the coat-tails" of the "power of attraction, the reputation and the prestige of" the more established brand, exploiting the marketing efforts made to maintain the famous brand image.

Not only did the court hold that trade mark infringement can occur without any requirement to establish these types of harm, but that the protection of the Comparative Advertising Directive (which allows comparative reference to be made to other people's trade marks in advertisements) is not available where such unfair advantage is established.

The finding was a significant blow to own brand products, which could, as in this case, be open to far easier attack from trade mark owners. Sainsbury's issued a statement to the effect that its customers "are savvy enough to know exactly what they're buying, the clue is in the name, and we see no basis for such claim" and that it intends to "vigorously" defend the claims.

It will be of great interest to trade mark owners and own brand retailers alike if this matter comes before the courts in the UK as the legal position of own brand products has, if anything, been less certain, rather than more certain, since the L'Oreal ruling.