Case: D&eacute;cor Corporation Pty Ltd v Dart Industries Inc (1988) 13 IPR 385
Outcome: applied
The ordinary rules of construction that apply to any written instrument are applicable to the construction of the specification of a patent: Nobel's Explosives Co Ltd v Anderson (1894) 11 RPC 519 at 523; D&eacute;cor Corporation Pty Ltd v Dart Industries Inc (1988) 13 IPR 385 (' D&eacute;cor ') at 391, 400; Photocure at [168]. However, there are also a number of special considerations that are relevant to the construction of a patent. The general basis for these rules was explained by Hely J in Beltreco at [70]: 'A patent is a public instrument which grants the right to protection of a defined monopoly, for the consideration of the disclosure of the invention to the general knowledge base of society. It is the need for balance between these symbiotic, yet competing interests which underscores the rules of patent construction.' 16 It is well established that the claims contained in the specification set out the legal limits of the monopoly. Yet, when construing the claims and determining the nature and extent of this monopoly it is necessary to consider the context in which the claims are made. This requires a consideration of the specification as a whole even if there is no apparent ambiguity in the claim; Minnesota Mining &amp; Manufacturing Co v Beiersdorf (Australia) Ltd [1980] HCA 9 ; (1980) 144 CLR 253 (' Minnesota Mining ') at 267-272; D&eacute;cor at 410-411; Beltreco at [75]-[78]. The specification is made up of several parts which have different functions: Welch Perrin &amp; Co Pty Ltd v Worrel [1960] HCA 91 ; (1961) 106 CLR 588 (' Welch Perrin ') at 610; D&eacute;cor at 391, 398; Beltreco at [73]. Nevertheless, reference to it as a whole may explain or elucidate the background to the claims, assist in ascertaining the meaning of a technical term or in resolving ambiguities in the construction of claims: Martin v Scribal Pty Ltd [1954] HCA 48 ; (1954) 92 CLR 17 (' Martin ') per Taylor J at 97; Welch Perrin at 610-611; Electric &amp; Musical Industries Ltd v Lissen Ltd (1939) 56 RPC 23 (' Electric &amp; Musical Industries ') at 41-42, Interlego AG v Toltoys Pty Ltd [1973] HCA 1 ; (1973) 130 CLR 461 (' Interlego ') at 478-479; D&eacute;cor at 400; Sartas No 1 Pty Ltd v Koukourou &amp; Partners Pty Ltd (1994) 30 IPR 479 (' Sartas ') at 486; Beltreco at [75]. 17 It is important, however, that the focus of the inquiry remain on the claims under consideration. If claims are clear and unambiguous, they are not to be varied, qualified or made obscure by statements found in other parts of the patent: Welch Perrin at 610; Interlego at 478-479; Electric &amp; Musical Industries at 41; Rosedale Associated Manufacturers Ltd v Carlton Tyre Saving Co Ltd [1960] RPC 59 at 69; Cooper Industries Inc v Metal Manufactures Ltd (1994) 29 IPR 106 at 113; Lantech Inc v First Green Park Pty Ltd (1995) 31 IPR 327 at 333; Beltreco at [74]. It is not legitimate to narrow or expand the boundaries of the monopoly as fixed by the words of the claims by adding to those words a gloss drawn from other parts of the specification: Welch Perrin at 610; D&eacute;cor at 391, 398; Braas &amp; Co GmbH v Humes Ltd (1993) 26 IPR 273 at 284; Beltreco at [74]. 18 A patent specification should be given a purposive rather than a purely literal construction: Catnic Components Ltd v Hill &amp; Smith Ltd [1982] RPC 183 (' Catnic ') at 242-243; D&eacute;cor at 400; Improver Corporation v Remington Consumer Products Ltd [1990] FSR 181 (' Improver '); Nicaro Holdings Pty Ltd v Martin Engineering Co (1989-1990) 16 IPR 545 at 560-561; Commonwealth Industrial Gases Ltd v M W A Holdings Pty Ltd (1970) 44 ALJR 385 at 388; Beltreco at [81]; Kirin-Amgen Inc v Hoeschst Marion Roussel Ltd (2004) 64 IPR 444 (' Kirin-Amgen '); Sachtler at [43]-[67]. It is inappropriate, however, to approach construction of the specification with a view to being 'fair' to the patentee; Kirin-Amgen at [33]; Sachtler at [60]. The fact that the monopoly is granted in consideration for the disclosure of the invention to the general knowledge base of society must be recognised: Beltreco at [70]. Indeed, the principles governing a definition of a monopoly operating over the public at large require a description of the claims that 'is not reasonably capable of misunderstanding': Martin at 59. The patentee must define the invention with sufficient precision to permit the monopoly to be determined and allow the general public to identify from the words of the claims the conduct prohibited: British United Shoe Machinery Co Ltd v A Fussell &amp; Sons Ltd (1908) 25 RPC 631 at 650-651. The public are entitled to be able to design around the monopoly claimed in a patent and therefore they must be able to determine reliably the scope of the claims: Beloit Technologies Inc v Valmat Paper Machinery Inc [1895] 24 RPC 705 at 720. 20 The hypothetical addressee of the patent specification is the non-inventive person skilled in the art before the priority date: Welch Perrin at 610; Populin v HB Nominees Pty Ltd (1982) 41 ALR 471 (' Populin ') at 476-477; Fisher &amp; Paykel Healthcare Pty Ltd v Avion Engineering Pty Ltd (1991) 103 ALR 239 at 260; D&eacute;cor at 397; Stanway Oyster Cylinders Pty Ltd v Marks (1996) 66 FCR 577 at 582-583; Beltreco at [81]; Kimberly-Clark Australia Pty Limited v Arico Trading International Pty Limited [2001] HCA 8 ; (2001) 207 CLR 1 at [24] ; Gambro Pty Ltd v Fresenius Medical Care South East Asia Pty Ltd (2004) 61 IPR 442 at [113]; Rhone-Poulenc Agrochimie SA v UIM Chemical Services Pty Ltd (1986) 12 FCR 477 at 496; NV Philips Gloeilampenfabrieken v Mirabella International Pty Ltd (1993) 26 IPR 513 (' NV Philips ') at 531; Catnic at 225; Wheatley (Davina) v Drillsafe Ltd [2001] RPC 7 at 141 142. Thus, the words used in a specification are to be given the meaning that the hypothetical addressee would attach to them, both in the light of his or her own general knowledge and what is disclosed in the body of the specification: D&eacute;cor at 391; Photocure at [170]. 25 A feature of a claim is considered essential if the hypothetical reader (that is, a reader skilled in the art before the priority date) would have understood from the language used in the claim, in the context of the specification as a whole, that the patentee intended that strict compliance was an essential requirement of the invention: Catnic at 243; D&eacute;cor at 400; Populin at 476; Beltreco at [81].