Case: Kirin-Amgen Inc v Hoechst Marion Roussel Ltd (2004) 64 IPR 444
Outcome: cited
More recently, Bennett J made the following observations in Sachtler GMBH &amp; Co KG v RE Miller Pty Ltd (2005) 221 ALR 373 at [42] (referred to by the Full Court in Synthetic Turf Development Pty Limited v Sports Technology International Pty Limited (2005) 67 IPR 475): &#8226; When determining the nature and extent of the monopoly claimed, the specification must be read as a whole. As a whole it is made up of several parts and those parts have different functions. The claim, cast in precise language, marks out the legal limits of the monopoly granted by the patent. What is not claimed is disclaimed. The specification describes how to carry out the process claimed and the best method known to the patentee of doing that: Beltreco at [73]. &#8226; Although the claims are construed in the context of the specification as a whole, it is not legitimate to narrow or expand the boundaries of monopoly, as fixed by the words of a claim, by adding to those words glosses drawn from other parts of the specification. If a claim is clear and unambiguous, it is not to be varied, qualified or made obscure by statements found in other parts of the document: Beltreco at [74]. &#8226; Terms in the claim which are unclear may be defined or clarified by reference to the body of the specification: Welch Perrin at 610; Interlego at 479, both approved in Kimberly-Clark at [15]. &#8226; Reference may be made to the body of the specification to understand the context in which words have been used: Beltreco at [77] following Minnesota Mining &amp; Manufacturing Co v Beiersdorf (Aust) Ltd [1980] HCA 9 ; (1980) 144 CLR 253 at 272. &#8226; It is legitimate to refer to the rest of the specification to explain the background to the claims, to ascertain the meaning of technical terms and to resolve ambiguities in the construction of the claims. Where the language of the claim is obscure or doubtful the doubt is sometimes resolved by referring to words in the body of the document to explain it: Beltreco at [75]. &#8226; It is not necessary first to construe the claims without reference to the specification and then to determine whether or not ambiguity exists: D&eacute;cor at 410; Beltreco at [76]; PhotoCure at [174]. &#8226; There is a fine line between, on the one hand, reading down the words of a patent claim to reflect how a person skilled in the art would understand it in a practical and commonsense way and, on the other hand, impermissibly limiting the clear words of a claim because a reader skilled in the art would be likely to apply those wide words only in a limited range of all the situations they describe: Stanway Oyster Cylinders Pty Ltd v Marks (1996) 66 FCR 577 at 585 per Drummond J. &#8226; The construction of the claim determines infringement, on both textual and substantive bases: Catnic Components Limited v Hill &amp; Smith Ltd [1982] RPC 183 at 242 at 242; PhotoCure at [158]. It is a question of whether the alleged infringement is covered by the language of the claim: Improver Corporation v Remington Consumer Products Ltd [1990] FSR 181 at 189-190 cited in Photocure at [158]. &#8226; A patent should be given a purposive construction: Catnic at 242-3. However, that does not involve extending or going beyond the definition of the technical matter for which the patentee seeks protection in the claims. The question is always what the person skilled in the art would have understood the patentee to be using the language of the claim to mean. For this purpose, the language chosen is usually of critical importance: Kirin-Amgen Inc v Hoeschst Marion Roussel Ltd [2004] UKHL 46 ; (2004) 64 IPR 444; [2005] 1 All ER 667 at [34] . &#8226; Purposive construction, permitting consideration of whether the person skilled in the art would understand a variant that does not strictly comply with the particular descriptive word used in the claim may still fall within the monopoly, does not arise where the variant would in fact have a material effect upon the way the invention worked: Catnic at 243; Kirin-Amgen at [50]. 57 It is clear that in construction of patents, one is not concerned with what the author meant to say. It is rather, what the notional addressee would have understood the author to mean by using those words: see Kirin-Amgen Inc v Hoechst Marion Roussel Ltd (2004) 64 IPR 444 per Lord Hoffman at [32]. His Lordship went on to consider at [34] what is meant by 'purposive construction', as follows: "Purposive construction" does not mean that one is extending or going beyond the definition of the technical matter for which the patentee seeks protection in the claims. The question is always what the person skilled in the art would have understood the patentee to be using the language of the claim to mean. And for this purpose, the language he has chosen is usually of critical importance. The conventions of word meaning and syntax enable us to express our meanings with great accuracy and subtlety and the skilled man will ordinarily assume that the patentee has chosen his language accordingly. As a number of judges have pointed out, the specification is a unilateral documents in words of the patentee's own choosing. Furthermore, the words will usually have been chosen upon skilled advice. The specification is not a document inter rusticos for which broad allowances must be made. On the other hand, it must be recognised that the patentee is trying to describe something which, at any rate in his opinion, is new; which has not existed before and of which there may be no generally accepted definition. There will be occasions upon which it will be obvious to the skilled man that the patentee must in some respect have departed from conventional use of language or included in his description of the invention some element which he did not mean to be essential. But one would not expect that to happen very often. 58 It is well settled that the plain and unambiguous meaning of a claim cannot be varied or qualified by reference to the body of the specification. In particular, it is not legitimate, in the absence of an express reference in the claim itself to import into a claim, features of the preferred embodiment. The preferred embodiment cannot be used to introduce into the definite words of a claim an additional definition or qualification of the patentee's invention. 59 The dispute between the parties stems from ambiguities which exist as a result of certain wording used in the patent. Fundamentally, those ambiguities reflect a difference of opinions within the relevant audience, namely the skilled addressee, as to the proper meaning of the words 'emulsion' and 'phase'. I set out below a relatively brief summary of the competing views as to the correct definition of these words, along with some other chemical principles and concepts which are relevant to the current dispute and to the evidence which was given during the course of the trial.