Registered Design

Registered Design Judgment – Chiaro Technology Limited v Mayborn Limited

In the recent High Court case of Chiaro Technology Limited v Mayborn (UK) Limited, it was held that the defendant’s Tommee Tippee electrical breast pump product did not infringe the claimant’s registered designs for a wearable electric breast pump device.

The facts

The claimant alleged that the defendant had infringed three of its registered designs for a wearable breast pump device. These registered designs related to: (1) the shape of the pump as a whole; (2) the front housing of the design; and (3) the milk collection device (“MCV”). The claimant had incorporated most of the features of these designs in the design of its ‘Elvie’ breast pump.

The defendant’s product was a wearable breast pump device marketed under the Tommee Tippee brand called the Made for Me Wearable Breast Pump (“MFM”).

The law

The claimant alleged infringement under section 7(1) of the Registered Designs Act 1949 (“RDA”), in that the defendant’s MFM product did not produce a different overall impression on the informed user (i.e. a nursing mother or wet nurse).

The defendant relied in particular on section 1C(1) of the RDA, which provides that “a right in a registered design shall not subsist in features of appearance of a product which are solely dictated by the product’s technical function”. The defendant’s case was that many features of the claimant’s registered designs were dictated by the product’s technical function and therefore should be excluded from protection under s.1C(1). For example, the defendant argued that the face of the device had to be broadly oval-shaped in order to fit properly inside the user’s bra, and therefore this aspect of the shape of the device was purely functional.


The judge, Mann J, held that the defendant’s MFM product did not infringe the claimant’s registered designs. In reaching this decision, the judge undertook the normal stepwise infringement analysis:

  1. Identify the sector to which the products in which the designs are intended to be incorporated or to which they are intended to be applied belong;
  2. Identify the informed user and having done so decide (a) the degree of the informed user’s awareness of the prior art and (b) the level of attention paid by the informed user in the comparison, direct if possible, of the designs;
  3. Evaluate the designer’s degree of freedom in developing their designs, ignoring any features of those designs which were dictated solely by technical function
  4. Assess the outcome of the comparison between the registered design and the contested design, taking into account (a) the sector in question, (b) the designer’s degree of freedom, and (c) the overall impressions produced by the designs on the informed user, who will have in mind any earlier design which has been made available to the public.

The relevant sector

It was held that the relevant sector was electrical breast pumps (as opposed to manual breast pumps). The sector was not restricted to wearable in-bra breast pumps.

The informed user

The informed user was held to be a nursing mother or wet nurse, who had a consumer’s view of the product (rather than that of a designer or a manufacturer).

Design freedom, features solely dictated by technical function and assessment of the overall impressions

Citing the CJEU’s decision in DOCERAM, the judge noted that:

  • As to whether a given feature of a design was solely dictated by technical function, this must be assessed objectively, rather than taking into account the subjective views of the creator of the design. This approach was more consistent with principle and with the bulk of the caselaw.
  • The defendant’s approach of seeking to rely on the registered design owner’s patent, which was a patent equivalent of the registered designs, as demonstrating conclusively that the features covered by the patent were functional for the purposes of s.1C(1), was incorrect. At most, a patent could be taken into account as a starting point to show objective evidence of functionality. It could not form conclusive evidence to this effect.

Applying these principles to the registered designs, the judge held that some, but not all, features of the registered designs were solely dictated by technical functional and therefore those features  would be excluded from protection under s.1C(1) of the RDA . Given that certain features were solely dictated by technical function, there was therefore limited design freedom.

In what design freedom still remained, the judge held that the differences between the defendant’s MFM product and the claimant’s registered designs would create a different overall different impression on the informed user. The claimant’s registered designs were therefore not infringed.


Relatively few design cases come to trial in the UK and so this judgment will be of interest to rights holders and designers, as well as legal practitioners. The principle point of interest in this case (in what was otherwise a fairly conventional infringement analysis) was the significance of the claimant’s patent on the assessment of whether certain features of the registered designs would be deemed “solely dictated by technical function”. The Judge held that it was proper to consider an appropriate patent when assessing the issue of technical functionality because the patent could be evidence of “the objective circumstances indicative of the reasons which dictated the choice of features of appearance of the product concerned” as required by DOCERAM. However, the Judge held that it would be wrong to treat the patent as a conclusive statement that the features of the registered design were therefore solely dictated by technical function.

The Judge’s treatment of the role of a patent in the ‘technical function’ assessment for design protection is consistent with the body of case law, both in the UK and EU. Whilst a patent could of course be relevant (in that it might articulate the technical function(s) performed by a given design feature), such a document, being of a necessarily technical nature, cannot rule out the possibility that considerations other than technical considerations, such as visual considerations (i.e. how the product looked) had also played some kind of a role in the design feature.

The interplay between registered designs and patents is an important one. Businesses in many sectors create new products embodying both a technical invention of some sort and a new design. The creator of such a product will frequently seek to protect these different types of intellectual property in such a product by applying for both patent protection in respect of the technical invention and registered design protection in respect of the product’s appearance. Given that it is customary to include illustrative figures in a patent demonstrating embodiments of the claimed invention, a patent will frequently also include images of the product’s design. If the mere presence of the design in the patent document were to lead to a conclusion that the design must therefore have been solely dictated by technical function (and so be invalid), that would unfairly undermine the ability to obtain design protection for a product which also happened to embody a patented invention.