Numbers in Patent Drawings – can they be used to construe the claims?
In a decision at the end of 2014 (Jarden Consumer Solutions (Europe) Ltd v SEB SA & Another  EWCA Civ 1629), the Court of Appeal has reversed a High Court decision which had found that the Breville Halo Health fryer (the “Halo”) infringed SEB’s European patent (UK) 2085003B. The key issue concerned the extent to which the reference numbers in the patent drawings can be used to interpret the claims.
Under EPC a69, the extent of protection conferred by a European patent shall be determined by the claims, but the description and drawings shall be used to interpret the claims. Although reference signs should be inserted in the claims where the application contains drawings, such signs shall not be used to limit the claims (Rules 43(6) and (7) EPC).
The claim at issue in EP 2085003B requires that the main heater means of the dry fryer is “mounted on the main body”. The specification described the main body 2 as having three parts: a base 2A, a side skirt 2B and a lid 2C (shown in Figures 5 and 8). The defendant argued non-infringement on the basis that as the Halo contained the heater in the lid, it did not satisfy the requirement that the main heater was mounted on the main body.
At first instance, the Patents Court found that certain claims of the SEB patent were invalid as obvious over the prior art but that the Halo, a dry fryer, infringed other claims. In finding infringement, the Court referred to the reference numerals in the drawings in order to determine what the person skilled in the art would have understood the patentee to have been using the language of the claim to mean. Concluding that the skilled reader would consider that the lid was part of the main body, the Court stated that “It is not using the reference numerals in the claim to construe the claim, and certainly not to limit the scope of the claim. Rather, it is taking proper account of the system of numbering used in the specification, and the message which that conveys about the relationship between the respective parts”.
In December 2014, the Court of Appeal considered the claim construction, finding that the High Court judge erred in allowing the numerals themselves to influence the construction of the claim, in particular allowing the lid to be considered to form part of the ”main body”. The Court of Appeal construed the claims without referring to the drawings and concluded that the language of the claims clearly excluded the lid from the scope of the term “main body”. In light of this approach, the Court found that the Halo did not infringe the SEB claims.
We are often asked by clients in other jurisdictions (particularly those where the practice is not customary) whether including reference numerals in claims can have any limiting effect on the scope of protection. This decision provides welcome reassurance that, at least in the UK, that is not the case.