Those who have been involved in an IP dispute in a UK court may be aware of the hypothetical person test. In order to determine whether IP has been infringed, the court reimagines itself as a hypothetical person of certain qualities and knowledge to judge whether one party’s IP right has been infringed by another’s. The confusing part is that there are different hypothetical people depending on whether you have a trade mark dispute, a registered design dispute or a patent dispute (copyright and unregistered design disputes wisely avoid the hypothetical person route and instead focus on substantive similarity between the two works/designs using a qualitative approach).
Trade Marks: Average Consumer
First up we have the average consumer test for trade marks. This is used by the court when considering whether two trade marks are similar. It can also be used to determine whether two marks are identical, in a situation where the differences between the marks are so minor it would not be noticeable to the average consumer.
The average consumer possesses the following qualities:
- They are reasonably well-informed, observant and circumspect.
- They rarely have the chance to make a direct comparison between the marks and are likely to have an imperfect recollection of the registered mark.
- Their attention varies according to the category of goods and services in question.
- They normally perceive a mark as a whole and do not proceed to analyse its various details.
Registered Designs: Informed User
The test for registered designs features the informed user. This is used by the court when considering whether the design made by the alleged infringer is the same or does not produce a different overall impression on the informed user when compared to the registered design. The informed user lies somewhere between the average consumer and the skilled person.
The informed user has the following characteristics:
- They are a user of the product in which the design is intended to be incorporated, not a designer, technical expert, manufacturer or seller.
- They have knowledge of the design corpus and of the design features normally included in the designs existing in the sector concerned.
- They are interested in the products concerned and show a relatively high degree of attention when using them.
- They conduct a direct comparison of the designs in issue, unless there are specific circumstances, or the devices have certain characteristics, which make it impractical or uncommon to do so.
- They take into account the designs’ notable features, similarities, differences and the prior art when conducting a comparison of the designs. They neither merely perceive the designs as a whole and do not analyse details, nor observe in detail minimal differences which may exist.
- They may discriminate between elements of a design when comparing it with the corresponding element of an accused design. Greater or lesser significance may be attached to similarities or differences, depending on the practical significance of the relevant part of the product or other reasons affecting the degree to which their appearance would matter to the informed user.
- They should not be taken to be aware that the arrangement shown in the registered design was optimal as compared to other possible arrangements.
- They are not an expert engineer and are not to be taken to be aware of all the engineering considerations which went into the finalisation of a particular design.
Patents: Skilled Person
Finally, we have the skilled person (or skilled addressee, or person skilled in the art – there are a lot of names for this one). The skilled person is used in a few different contexts:
- To determine whether the invention is taken to involve an inventive step, which must not be obvious to the skilled person, having regard to any matter which forms part of the state of the art;
- To determine whether the patent specification discloses the invention sufficiently to enable the skilled person to perform the invention;
- To determine whether information has been made available to the public, which must be sufficient to enable the skilled person to put what the disclosure teaches into effect;
- To determine whether a variant product infringes a patent because it varies from the invention in a way which is immaterial, in which the court considers whether the variant would be obvious to the skilled person reading the patent at the priority date, but knowing that the variant achieves substantially the same result as the invention in substantially the same way; and
- In patent claim construction, where the court considers what the skilled person is taken to have understood the patent owner to mean.
The skilled person exhibits the following attributes:
- They are uninventive but skilled in the area of technology to which the patent is directed.
- They are taken to have an ordinary level of skill, rather than being super-skilled.
- They are the person to whom the claims in the patent were addressed and have a practical interest in the subject matter of the claims and with practical knowledge and experience of the kind of work in which the invention was intended to be used.
- They possess the common general knowledge (“CGK”) in the technical field to which the invention relates, which guides how they read the specification of the patent and the prior art and affects how a technical problem might be solved. CGK includes not just information directly in the mind of the skilled person, but such information as they would be able to locate by reference to well-known textbooks. The skilled person does not need to have committed all this knowledge to memory, but they would be aware of standard places to look for the information needed.
- They are taken to have read all of the prior art.
- They share the common prejudices or conservatism which prevails in the art concerned, and they are incapable of a scintilla of invention.
- They have been characterised as a ‘nerd’.
