Dyson Ltd v Vax Ltd

Registered design infringement depends on whether the accused design produces a different overall impression on the informed user. The comparison is primarily visual and must consider the registered design, the accused article and the existing design corpus.

The informed user is particularly observant and has some awareness of prior designs. A marked departure from the prior art generally attracts broader protection. The court must nevertheless consider the designer’s freedom, including technical constraints affecting particular features. Features cannot be reduced to general verbal descriptions and treated like the claims of a patent.

An appellate court should reverse the trial judge’s evaluative conclusion only for an error of principle.

Dyson Ltd owned a valid UK registered design for the shape and configuration of its DC02 cylinder vacuum cleaner. Arnold J held in [2010] EWHC 1923 (Pat) that Vax Ltd’s Mach Zen C-91 MZ vacuum cleaner did not infringe because it produced a different overall impression on the informed user.

Dyson appealed with the judge’s permission. It argued that the registered design was a striking departure from the existing design corpus and therefore deserved broad protection. It contended that the judge had attributed excessive significance to technical considerations and had understated the visual effect of nine asserted similarities.

The central issue was whether the judge had erred in principle when applying article 9 of the Designs Directive 98/71 and deciding that the two designs produced different overall impressions.

1. Appeal dismissed. The judge had made no material error of principle. The Mach Zen produced a different overall impression on the informed user and therefore did not infringe the registered design.

2. The infringement inquiry was primarily visual. What mattered most was the appearance of the registered design, the accused object and the prior art. The informed user was reasonably discriminatory, used the relevant product and possessed some awareness of previous designs. Such a user paid a relatively high degree of attention.

3. Article 9(2) of the Designs Directive 98/71 referred to the freedom of the designer of the registered design, rather than the designer of the alleged infringement. The judge had technically referred to the wrong designer in places, but that caused no material error because there was no evidence that design freedom had changed between the two designs.

4. Design freedom could vary with the product’s technical specification. The judge was entitled to examine whether the claimed similarities had technical significance, including the inclined transparent bin, large rear wheels, wheel spacing and prominent wheel arches. This did not penalise an ingenious design or treat its success as reducing protection.

5. A design markedly different from the existing design corpus was likely to have greater visual impact and correspondingly broader protection. The judge expressly allowed a fairly broad scope of protection. He was nevertheless entitled to find significant differences in the articles’ shapes, proportions, handles, wheel arches, hose connections, rear views and overall styling. General descriptions of common features could not be treated like patent claims.

6. Sir Robin Jacob agreed with the judge’s characterisation of the registered design as smooth, curving and elegant and the Mach Zen as rugged, angular and industrial. Even on an independent comparison, the designs produced different overall impressions.

7. Jackson LJ added that expert evidence in registered design cases had a limited role. In this case it was required or admissible only concerning technical constraints on design freedom. Courts should define and focus the issues addressed by experts to control costs. Black LJ agreed with both judgments.

1. Court of Appeal (Civil Division): The appeal was dismissed. The court upheld the conclusion that the accused vacuum cleaner did not infringe the registered design: [2011] EWCA Civ 1206.

2. High Court of Justice, Chancery Division: Arnold J held that the valid UK registered design was not infringed because the accused cleaner produced a different overall impression on the informed user: [2010] EWHC 1923 (Pat).