Principles
25 Other than as noted above, the parties articulated the relevant principles in the same terms, albeit with a different emphasis reflecting their competing interests. Accordingly they agreed that: - (i) the hearing under s 60(4) of the Act was a hearing de novo, (ii) Memcor, as the applicant opposing the grant, bore the onus of proof, (iii) Memcor's onus was to satisfy the Court that, if granted, the patent would be invalid, (iv) while it was appropriate for the Court to accord respect to the views expressed by the Commissioner's delegate, particularly where the delegate has relevant technical knowledge or experience, the evidence before the Court in the present case was different from that before the delegate, and (v) specifications are not to be read in the abstract but in light of common general knowledge and "the state of the art and the manufacture at the time" (Kimberly-Clark Australia Pty Ltd v Arico Trading International Pty Ltd (2001] 207 CLR 1; [2001] HCA 8 at [24]).
26 Memcor emphasised the policy of the Act to guard against "claim broadening" (evidenced by, for example, ss 79B and 102 of the Act) and the need to construe claims having regard to that policy. Memcor also stressed: - (i) the status of a patent as a public document marking out the field of a monopoly (Flexible Steel Lacing Company v Beltreco Ltd (2000) 49 IPR 331; [2000] FCA 890 at [70]), (ii) the need for the territory of the monopoly to be marked out with reasonable clarity by the claim construed fairly in the light of the relevant prior art (Rodi & Weinberger AG v Henry Showell Ltd [1969] RPC 367 at 391-392), (iii) the important aphorism in patent law that what is not claimed is disclaimed (Walker v Alemite Corporation (1933) 49 CLR 643 at 656-657 citing Fellows v Thomas William Lench Ltd (1917) 34 RPC 45 at 55), and (iv) the need to recognise that patentees have their own reasons for casting their claims in particular terms about which the Court may not speculate, thus confirming the need for caution in accepting any suggestion that an apparent limitation upon a claim "is merely the product of a slip of the pen" (Fisher & Paykel Healthcare Pty Ltd v Avion Engineering Pty Ltd (1991) 103 ALR 239 at 256).
27 Memcor also referred to the continuing utility and particular aptness of the observations of Lord Russell in Electric and Musical Industries Ltd v Lissen Ltd [1938] 4 All ER 221 at 224 - 227 to the present case, namely:
The Court of Appeal have stated that in their opinion no special rules are applicable to the construction of a specification, that it must be read as a whole and in the light of surrounding circumstances, that it may be gathered from the specification that particular words bear an unusual meaning, and that, if possible, a specification should be construed so as not to lead to a foolish result, or one which the patentee could not have contemplated. They further have pointed out that the claims have a particular function to discharge. With every word of this I agree, but I desire to add something further in regard to the claims in a specification. The function of the claims is to define clearly and with precision the monopoly claimed, so that others may know the exact boundaries of the area within which they will be trespassers. Their primary object is to limit, and not to extend, the monopoly. What is not claimed is disclaimed. The claims must undoubtedly be read as part of the entire document, and not as a separate document. Nevertheless, the forbidden field must be found in the language of the claims, and not elsewhere. It is not permissible, in my opinion, by reference to some language used in the earlier part of the specification to change a claim which by its own language is a claim for one subject-matter into a claim for another and a different subject-matter, which is what you do when you alter the boundaries of the forbidden territory. A patentee who describes an invention in the body of a specification obtains no monopoly unless it is claimed in the claims. As Lord Cairns LC said, there is no such thing as infringement of the equity of a patent: Dudgeon v Thomson.
…
I would point out that there is no question here of words in the first claim bearing any special or unusual meaning by reason either of a dictionary found elsewhere in the specification or of technical knowledge possessed by persons skilled in the art. The prima facie meaning of words used in a claim may not be their true meaning when read in the light of such a dictionary, or of such technical knowledge, and, in those circum-stances, a claim, when so construed, may bear a meaning different from that which it would have borne had no such assisting light been available. That is construing a document in accordance with the recognised canons of construction. However, I know of no canon or principle which will justify one in departing from the unambiguous and grammatical meaning of a claim and narrowing or extending its scope by reading into it words which are not in it, or which will justify one in using stray phrases in the body of the specification for the purpose of narrowing or widening the boundaries of the monopoly fixed by the plain words of a claim.
A claim is a portion of the specification which fulfils a separate and distinct function. It, and it alone, defines the monopoly, and the patentee is under a statutory obligation to state in the claims clearly and distinctly what is the invention which he desires to protect. As Lord Chelmsford said in this House many years ago in Harrison v Anderston Foundry Co, at p 581:
The office of a claim is to define and limit with precision what it is which is claimed to have been invented and therefore patented.
If the patentee has done this in a claim the language of which is plain and unambiguous, it is not open to your Lordships to restrict or expand or qualify its scope by reference to the body of the specification. Lord Loreburn LC, emphasised this when he said in Ingersoll Sergeant Drill Co v Consolidated Pneumatic Tool Co Ltd, at p 83:
The idea of allowing a patentee to use perfectly general language in the claim, and subsequently to restrict, or expand, or qualify what is therein expressed by borrowing this or that gloss from other parts of the specification, is wholly inadmissible.
The same view was expressed by Romer LJ in the following felicitous language in British Hartford-Fairmont Syndicate Ltd v Jackson Bros (Knottingley) Ltd, at p 556:
One may, and one ought to, refer to the body of the specification for the purpose of ascertaining the meaning of words and phrases used in the claims or for the purpose of resolving difficulties of construction occasioned by the claims when read by themselves. But where the construction of a claim when read by itself is plain it is not in my opinion legitimate to diminish the ambit of the monopoly claimed merely because in the body of the specification the patentee has described his invention in more restricted terms than in the claim itself.
28 GE emphasised that the applicant in opposition proceedings bore an onus heavier than in ordinary civil proceedings. The purpose of opposition proceedings is to provide a "swift and economical means of settling disputes that would otherwise need to be dealt with by the courts in more expensive and time-consuming post-grant litigation…by ensuring that bad patents do not proceed to grant" (Genetics Institute Inc v Kirin-Amgen Inc (1999) 92 FCR 106; [1999] FCA 742 at [19]). Consistent with this policy and the availability of subsequent revocation proceedings, GE noted references in various decisions to the effect that the Court must be "practically certain" or "clearly satisfied" that a patent granted on the application would be invalid (Genetics Institute at [17]; E I Du Pont de Nemours & Co v ICI Chemicals & Polymers Ltd (2003) 128 FCR 392; [2003] FCA 291 at [25]; Austal Ships Pty Ltd v Stena Rederi Aktiebolag (2005) 66 IPR 420; [2005] FCA 805 at [6]; and F Hoffman-La Roche AG v New England Biolabs Inc (2000) 99 FCR 56; [2000] FCA 283 at [67]). GE also referred to authority to the effect that a claim should be given a construction which makes the invention workable in preference to one according to which the invention may not do so (Pfizer Overseas Pharmaceuticals v Eli Lilly & Co (2005) 225 ALR 416; [2005] FCAFC 224 at [250]).
29 GE also referred to the useful summary by the Full Court in Kinabulu Investments Pty Ltd v Barron & Rawson Pty Ltd [2008] FCAFC 178 at [44] - [45], subsequently adopted by another Full Court in PAC Mining Pty Ltd v Esco Corporation [2009] FCAFC 18 at [29] as follows:
[44] …When determining the nature and extent of the monopoly claimed, the specification must be read as a whole. But as a whole it is made up of several parts which have different functions. The claims mark out the legal limits of the monopoly granted. The specification describes how to carry out the process claimed and the best method known to the patentee of doing that. 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. It is legitimate, however, to refer to the rest of the specification to explain the background of the claims, to ascertain the meaning of technical terms and resolve ambiguities in the construction of the claims. See Flexible Steel Lacing Co v Beltreco Ltd (2000) 49 IPR 331 at [73]-[75] (Hely J).
[45] Other more specific principles of construction collected in Flexible Steel at [81] are:
· a specification should be given a purposive construction rather than a purely literal one;
· the hypothetical addressee of the specification is the non-inventive person skilled in the art before the priority date;
· the words used in a specification are to be given the meaning the hypothetical addressee would attach to them, both in the light of the addressee's own general knowledge and in the light of what is disclosed in the body of the specification;
· as a general rule, the terms of the specification should be accorded their ordinary English meaning;
· evidence can be given by experts on the meaning those skilled in the art would give to technical or scientific terms and phrases, and on unusual or special meanings given by such persons to words which might otherwise bear their ordinary meaning;
· however, the construction of the specification is for the Court, not for the expert. In so far as a view expressed by an expert depends upon a reading of the patent, it cannot carry the day unless the court reads the patent in the same way.