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Line drawings assist (again) in proving design infringement

Posted on 6 August 2021

In Lutec v Cascade, David Stone, sitting as a Deputy High Court Judge in the Intellectual Property Enterprise Court (IPEC), has found infringement of two registered designs for outdoor light fittings. Crucial to the Court's assessment in this case was its interpretation of the scope of protection of the registered designs and specifically whether they claimed an absence of surface decoration. In coming to its decision, the Court said it would be very unusual for a line drawing in a registered design to claim an absence of surface decoration.

This case further clarifies the scope of protection of registered designs (especially those depicted using line drawings). It is also a helpful reminder of the importance of carefully choosing the correct medium in which to represent a registered design, be it a line drawing, Computer-Aided Design (CAD) rendering, or photograph; as this case shows, this choice can drastically affect the scope of protection of the design, and thereby any infringement prospects vis-à-vis competitors.


The Claimant alleged that its Registered Community Designs (RCD) 0001 (depicted below) was infringed by the Defendants' "Up or Down Light", and that its RCD 0002 was infringed by the Defendants' "Up and Down Light", both shown as follows:

A registered design will be infringed where the allegedly infringing product does not produce a 'different overall impression' from that design. Here, the Defendants had conceded pre-trial that the degree of freedom of the designer of the RCDs (i.e. of outdoor light fittings) was considerable, which meant the designs were afforded a wider scope of protection.


The IPEC decided the Defendants' lights infringed the RCDs. The Defendants had argued that the line drawings used for the RCDs claimed an absence of surface decoration, and that because their lights displayed a ridged surface (specifically, between the two lines on the curved surface), there was a different overall impression, and therefore no infringement.

The Court considered a number of important recent design cases, including the Supreme Court decision in Trunki (which established that a proper analysis of the scope of protection must turn on, in particular, the images of the registration) and Rothys (which held that this assessment is a question of fact, the most important of which is what the drawings look like – see our commentary here).

In particular, the Deputy Judge referred to Lord Neuberger's obiter comments in Trunki, where he said that an absence of surface decoration can, as a matter of principle, be an aspect of a design, and this includes where the design is depicted by line drawings (see, for example Apple v Samsung in which Apple successfully argued in its infringement claim against Samsung that its RCD for the iPad claimed an absence of surface decoration on the screen as a positive design feature). However, the Deputy Judge agreed with Lord Neuberger that line drawings are the least appropriate way of showing surface decoration, colour or decoration, compared to CAD renderings or photographs. It would therefore be a "very unusual case indeed" in which a line drawing in a registered design claims an absence of surface decoration, and this case was not one of them. The scope of protection claimed by the RCDs was to the overall shape of the lights. Given the wide design freedom and that the differences between the RCDs and the Defendants' products were minor, this finding was decisive.

Line drawing, CAD rendering or photograph

This case reinforces the notion that the chosen format for depicting a design may affect its scope of protection: it is generally agreed that the broadest claims in registered designs can be achieved by line drawings showing only the contours of the design. In Trunki, the Supreme Court (reluctantly) rejected the infringement claim because the RCD was interpreted to claim an absence of surface decoration (the RCD in that case was depicted by a CAD drawing). In Rothys, the use of line drawings to depict the design was also decisive but for a different reason: the court said the cross hatching depicted in the line drawing depicted the texture on the shoe design in question. This was an important point, as it was the application of that material (specifically, knitted yarn made of plastic) as applied to ballerina shoes that made that design valid over the prior art.

Designers may have good reasons for wanting to claim surface decoration, or an absence of surface decoration, as a positive design feature. However, the method of representation chosen can be an important one, and should be done with care. Another approach may be to depict the design using a variety of methods, to cover all bases.

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