The approach of the parties
20 The proceeding before the primary judge raised three main questions: whether the accused apparatus infringed the patent; whether the patent was valid; and whether the respondents, if liable for infringement, were joint tortfeasors.
21 The question of patent infringement raised four issues relating to the construction of the claims. All but one of those issues was determined in favour of the appellants. The issue determined adversely to the appellants, which was fatal to their case on infringement, was identified by the primary judge as "the device issue".
22 As apparently argued by the parties, and as determined by the primary judge, this issue concerned the meaning of the term "device" as used in the claims of the patent. The primary judge described the controversy as whether that term, as used in the claims, would encompass a core orientation tool (to use a neutral expression) in two or more separate and separated parts (as argued by the appellants) or whether it was limited to a unitary tool in a single assemblage (as argued by the respondents).
23 At trial the parties were in agreement that the term "device", as used in the claims, did not have a special or technical meaning, only its ordinary English meaning.
24 They accepted, however, that the words in a claim should be read through the eyes of the notional person skilled in the relevant art, in the context in which they appear, having regard to that person's own general knowledge and to what is disclosed in the body of the specification.
25 They accepted, also, that the construction of a specification, including the claims, is ultimately a question of law for the Court.
26 Nevertheless, the question of the meaning of "device" provoked a significant debate largely carried out through the evidence of expert witnesses called by the appellants (Professor Trevelyan and Dr Kepic) and the respondents (Dr Myers). There was no issue on appeal that each of these witnesses had expertise relevant to the attributes of the notional person skilled in the art. It seems doubtful, however, that all of their evidence was appropriately directed to the question of construction that fell for determination by the Court. This may be because, at trial, the debate focussed on the meaning of the term "device" used in engineering parlance rather than what the claims defined as the invention.
27 Thus Professor Trevelyan gave evidence about engineering objects comprising multiple, separate components, commonly referred to by engineers as a "device", such as an electric drill and its chuck, and the common car jack with detachable handle.
28 Dr Kepic gave evidence that those in the field of geophysics will refer to a number of physically separate components, which nevertheless work together to produce a result, as a "device". This evidence was exemplified by reference to data harvesting tools comprising a series of remote sensors and a separate hand held display unit, and differential GPS survey devices which comprised both a base station and a roving station.
29 The respondents criticised this evidence. They submitted that a broad understanding of the word "device" is not relevant to the words or text of the patent and cannot aid the task of construing the claims.
30 The primary judge rejected that submission, holding that, specifically in relation to the evidence given by Dr Kepic, such evidence was relevant to understanding "the point of view" from which the notional person skilled in the art would approach a reading of the patent. His Honour also reasoned that this evidence showed that Dr Kepic had a broad understanding of the term "device" outside his involvement in the present litigation which militated against an assertion that his evidence was contrived.
31 Dr Myers' evidence was similarly directed. The effect of his evidence was that, from a computer engineering perspective, a "device" refers to something that is physically interconnected, such as a semi-conductor device. Hence, according to Dr Myers' understanding, the word "device", as used in the claims, referred to "a physically integrated set of components capable of working together to produce some useful effect, such as an instrument".
32 The appellants criticised this evidence. They argued that this approach to the construction of the claims involved the erroneous adoption of a preconceived notion of the meaning of "device" that paid little regard to the text of the patent.
33 The primary judge accepted the force of this submission, to a point. His Honour accepted that Dr Myers approached the claims with an assumption as to how the word "device" was to be read, but checked this understanding against the text of the claims to see whether there was anything to challenge his view. It was not correct to say that Dr Myers had paid no regard to the text of the patent.
34 It can be seen, therefore, that the parties, although calling expert evidence on the question of claim construction, criticised the evidence of the other as being misdirected and, at least in certain aspects, foreign to the correct approach to claim construction.