Case: Lockwood Security Products Pty Limited v Doric Products Pty Limited (No. 2) [2007] HCA 21 ; (2007) 235 ALR 202
Outcome: considered
The issue of obviousness which arises in this case is whether a hypothetical person skilled in the relevant art in light of the common general knowledge as at 6 November 1995 would have regarded it as obvious, in the production of an improved wear assembly, to utilise a screw as a means of eliminating looseness in the wear assembly and thereby arrive at the claimed invention in Jones III: see s 7(2) of the Act ; Lockwood Security Products Pty Limited v Doric Products Pty Limited (No. 2) [2007] HCA 21 ; (2007) 235 ALR 202 at 231. When addressing this question, the Court must be careful not to substitute its own deduction or perception for that of the hypothetical person. Furthermore, as the High Court has stated on several occasions, "[a] scintilla of invention remains sufficient in Australian law to support the validity of a patent": see Lockwood 235 ALR at 217 and cases cited therein. 69 The applicants contend that the person skilled in the relevant art in this case is someone who works in the earthmoving industries who would be involved in the design and manufacture of wear assemblies and therefore would be familiar with factors relevant to their design and development. It is said by the applicants that Professor Wightley is not a person skilled in the relevant art because he had no experience in the design, operation or manufacture of wear assemblies attached specifically to excavators. 70 The respondents' contention is that only Professor Wightley and Messrs Meyers, Ashworth and McClanahan are persons skilled in the relevant art. It is said that Professor Wightley is a mechanical engineer with extensive experience in design and manufacture of replacement wear parts for use in the mining industry generally; Mr Meyers is a mechanical engineer with experience in the design, manufacture, sale and maintenance of replaceable wear parts for excavators; and Messrs Ashworth and McClanahan are relevantly skilled mechanical engineers. On the other hand, say the respondents, Mr Alden, the expert called by the applicants, is a structural engineer, which means he is not skilled in the relevant art. In addition, the respondents argue that the only witness called by the applicants on the issue of obviousness was Mr McClanahan (the co-inventor of the patents), and that the evidence called by the respondents in relation to this point was therefore not directly challenged by any qualified expert. 71 In my opinion, Professor Wightley and the other mechanical engineers whose evidence was adduced by the respondents have sufficient expertise to express the opinions as persons skilled in the art. However, for reasons given below, I do not accept Professor Wightley's evidence and the respondents' submission that the solution provided by the invention in Jones II and Jones III was obvious. 72 The applicants say that the invention in this case is an improved wear assembly which is constituted by the combination of elements set out in claims 1 and 51 of Jones II and claim 1 of Jones III. Each of these claims in suit, it is said, involves a combination of elements in a way that constitutes a new inventive thing, despite the fact that each of the elements (other than the lock adjustment assembly) was contained in the Toplok shroud, which the applicants' properly acknowledged formed part of the common general knowledge. In simpler terms, the new combination achieved by the patents in this case provided a new benefit beyond what had previously been provided, and was therefore inventive. 73 The applicants submit that the invention the subject of Jones II and Jones III was based on perceptions that: &#8226; the Toplok shroud provided a good foundation upon which to develop an improved wear assembly that could serve not only as a shroud but also as an adapter; &#8226; the forces to which an adapter may be exposed could produce looseness in mounting of the wear assembly to a Toplok style of mounting; and &#8226; this looseness could be overcome by an adjustment assembly that moved the relative positions of the bearing surfaces of the Toplok style lock so as to pull the wear assembly over the mount. 74 The applicants' argument is that the use of this type of adapter with a Toplok style of mounting was not part of the common general knowledge at the relevant date. Furthermore, the applicants say that, since there were at the relevant date many wear assemblies available to be used as the starting point to develop an improved assembly which overcame looseness between the wear member and the boss, the use of Toplok as the starting point was not required by any design principle, and was therefore not obvious. Indeed, as Professor Wightley acknowledged in cross-examination, even if an inventor were confined to the Toplok shroud as a starting point, there were several other locking methods known which may have been used instead of the method ultimately used in the invention. One such alternative method was the use of two piece pins, wedges and spools to take up any looseness in the wear assembly.