Peterson Portable Sawing Systems Ltd v Lucas
Anderson P, McGrath and Glazebrook JJ
Court of Appeal CA 64/03; CA 97/03, 4 March 2005
One of the live topics in patent law in New Zealand has been the scope and extent of the test of obviousness. The most recent elucidation of this test was provided by the Court of Appeal in Ancare New Zealand Limited v Cyanamid of New Zealand Limited [2003] 3 NZLR 299 at [43]:
That aside, the test is well established. It postulates a person (or, where appropriate, a team) skilled in the field but not inventive, invested with the common general knowledge available in the field at the priority date, presented with the prior knowledge or prior use relied upon. Prior documents may be looked at together if that is what the skilled person or team would do. It asks whether to that person or team the alleged inventive step would be obvious and would be recognised, without bringing to bear any inventiveness, as something that could be done or is at least worth trying. That is a question of fact. If any embodiment within the scope of the claim is obvious the claim is invalid. (emphasis added)
The decision of the High Court of Australia in AB Hassle v Alphapharm Pty Limited (2002) 212 CLR 411 has led to considerable discussion in New Zealand as to:
(a) The scope of what is encompassed within “at least worth trying” (the ‘worth a try’ test). For Australia, the ‘worth a try’ or ‘obvious to try’ test has been rejected. The consideration is now whether the relevant addressee or team “would … directly be led as a matter of course to try an particular thing in the expectation that it might well produce a useful result” (para [53]);
(b) The extent to which it must be shown that a skilled addressee for New Zealand had an awareness of the prior art documents alleged to form part of the common general knowledge - as opposed to the Court simply accepting the results of a later document search as amounting to admissible prior art.
The first of these issues, has been the subject of comment by the New Zealand Court of Appeal in the course of the Peterson case. There the appellant strongly attacked the trial judge for not having mentioned the ‘worth a try’ test in his decision. One of the appellant’s expert witnesses had given evidence at trial that a key part of the inventive step of the patent (covering a portable sawmill) was ‘worth a try’.
In rejecting this attack, the Court of Appeal made the following observations (para [85]):
Fisher J identified all the relevant principles, albeit that he did not specifically invoke the ‘worth a try’ test, the utility of which may well be moot. It seems to add little to the technique of ascertaining obviousness. Anything may be worth a try, depending on acceptable cost for potential benefit, but inventiveness may lie in deciding what to try. The crucial test is the statutory expression examined in terms of the orthodoxy of Windsurfing. Fisher J examined and marshalled the facts before him, taking into account indications of reliability or otherwise in the testimony and demeanour of the witnesses, applied the appropriate tests for the nature of the dispute and came to factual conclusions.
The Court of Appeal’s comments helpfully mark a real retreat from the worthwhile to try test - in line with the approach of the High Court of Australia. Worthwhile to try is a deceptively simple test that can mask a substantial amount of hindsight. Also it can effectively result in a lowering of the obviousness threshold. The Court of Appeal’s comment that inventiveness may lie in deciding what to try carries with it an echo of Barker’s J comments in Beecham v Bristol Myers (No. 2) [1980] 1 NZLR 192, 248:
I think the question must lie in the relationship of concept of obviousness to something; obvious to try for what? Worthwhile to try for what? Useful for what? It is not possible to speak of a claim being obvious in vacuo. It must be obvious to a particular end.
A further aspect of obviousness dealt with by the Court was the identity of the notional skilled addressee. The appellant had attacked the trial judge’s actual identification of the notional skilled addressee with one of the patentee’s expert witnesses (who had expressed the view that he wished he had thought of the inventive concept embodied in the patent). The Court held (para [82]):
There will be cases where the subject art is complex and diverse, with the skilled addressee possessing extensive arcane knowledge which must be evaluated by a trial judge. Yet other cases will concern an art less specialised and complex. In those cases, the scope for novelty and inventiveness may be relatively compressed and the notional skilled but imaginative addressee may be more readily identifiable.
The present case was held to be one of the latter type and the trial judge was “plainly entitled to have regard to reality in seeking to identify the notional” skilled addressee.