Inventive Step

Avoiding hindsight: the test for inventive step

4.15 A significant issue in examination is the use hindsight or ex post facto analysis. The Examiner should attempt to place themselves in the shoes of the person skilled in the art faced with the problem. This is difficult in practice since the Examiner approaches the consideration having both the problem and the solution in hand. Various approaches have been developed by the Courts to minimise the danger of hindsight in their considerations, and in Singapore the Courts have adopted the so called “Windsurfing approach”. Wherever possible the principles of this test should be followed in examination.

4.16 Nevertheless, as noted Jacob LJ in Angiotech Pharmaceuticals v Conor Medsystems Inc [2007] EWCA Civ 5, the threshold question is a relatively simple one:

“… one can over-elaborate a discussion of the concept of ― obviousness so that it becomes metaphysical or endowed with unwritten and unwarranted doctrines, sub-doctrines or even sub-sub-doctrines. … In the end the question is simply ― was the invention obvious?”

4.17 Similarly, in First Currency Choice Pte Ltd v Main-Line Corporate Holdings Ltd [2008] 1 SLR(R) 335, the Court recognised that it may be appropriate in some cases to apply a simpler approach:

“Be that as it may, simplicity is certainly to be appreciated, and, in assessing the obviousness of an alleged invention, it may sometimes suffice in straightforward cases to refer to the test formulated by Lord Herschell in Vickers, Sons And Co, Limited v Siddell (1890) 7 RPC 292, where he stated (at 304) that an invention lacked an inventive step if what was claimed was ‘so obvious that it would at once occur to anyone acquainted with the subject, and desirous of accomplishing the end’. Quite often, it is difficult, in practice, to break down the Windsurfing test … into its component parts. Thus, while the Windsurfing test remains a useful guide, it is no more than that. Above all, it should be borne in mind that the Windsurfing test is merely a manifestation of judicial inventiveness on how best to pragmatically interpret and elucidate the requirements of s 15 of the Act.”