citation(s): 2000 SCC 67; online; (2001) 9 C.P.R. (4th) 129 (S.C.C. per Binnie J.)
Case Comment © 1997-2004 Donald M. Cameron, Ogilvy Renault
[14, p. 137] The claims of the '803 patent specify "vanes" but do not further specify whether the vanes are to be flexible or rigid. Whirlpool's position is that flex vanes were not included. The appellants argue the contrary.
[20, p. 139] The appellants were also accused of infringing the '734 patent which explicitly stated that the vanes of the lower oscillator of the dual action agitator were flexible rather than rigid. The '734 patent disclosed the new "continuous drive" claims. Claim 1 set out the broad monopoly claim as follows:
1. An agitator assembly for a clothes washing machine comprising:
a first agitator element,
a second agitator element,
drive means for driving said first agitator element in an oscillatory motion and for concurrently driving said second agitator element in an unidirectional rotary motion, said first and second agitator elements cooperating to circulate the contents of the machine in a toroidal rollover pattern within the washing machine, and means associated with said second agitator element for forcing articles adjacent thereto into the oscillatory path of said first agitator element and into said rollover pattern, said first agitator element having formed thereon flexible vanes which are free to flex in response to oscillatory motions of the agitator element, thereby to yieldingly engage fabrics deflected downwardly and lessening high impact loading of the first agitator element. [Emphasis added.]
[39, p. 144-145] The source of the error in the courts below, according to the appellants, is the approach to claims construction which the Federal Court has developed based initially on a misunderstanding and misapplication of the "purposive construction" approach formulated by the House of Lords in Catnic Components Ltd. v. Hill & Smith Ltd.,  R.P.C. 183. The appellants say the Catnic decision "has had a detrimental impact throughout the Commonwealth jurisdictions, and in particular to a proper understanding of the common law of claim construction in Canada". The appellants invite the Court to reject the Catnic approach, and to overrule the Federal Court cases that follow it, particularly O'Hara Manufacturing Ltd. v. Eli Lilly & Co. (1989), 26 C.P.R. (3d) 1 (F.C.A.). In this respect, however, I agree with the observation of William L. Hayhurst, Q.C., that "[p]urposive construction is nothing new, though Lord Diplock is credited with first using the expression in patent cases" (see Hayhurst, "The Art of Claiming and Reading a Claim" in Patent Law of Canada (1994), edited by G. F. Henderson, Q.C., at p. 193).
[43, p. 146] The first step in a patent suit is therefore to construe the claims. Claims construction is antecedent to consideration of both validity and infringement issues. The appellants' argument is that these two inquiries -- validity and infringement -- are distinct, and that if the principles of "purposive construction" derived from Catnic are to be adopted at all, they should properly be confined to infringement issues only. The principle of "purposive construction", they say, has no role to play in the determination of validity, and its misapplication is fatal to the judgment under appeal.
[45, p. 147] The key to purposive construction is therefore the identification by the court, with the assistance of the skilled reader, of the particular words or phrases in the claims that describe what the inventor considered to be the "essential" elements of his invention. This is no different, I think, than the approach adopted roughly 40 years earlier by Duff C.J. in J. K. Smit & Sons, Inc. v. McClintock,  S.C.R. 279. The patent in that case related to a method of setting diamonds in devices such as rotary drill bits for earth boring. Duff C.J., citing the earlier jurisprudence, put the focus on the inventor's own identification of the "essential" parts of his invention, at p. 285:
Obviously, the invention, as described by the inventor himself, involves the use of air suction to hold the diamonds in place while the molten metal is being introduced into the mold. There can be no doubt, in my mind, that as the inventor puts it, that is an essential part of his process. That part of his process is clearly not taken by the appellants. Adapting the language of Lord Romer, it is not the province of the court to guess what is and is not of the essence of the invention of the respondent. The patentee has clearly indicated that the use of air suction at that stage of the process is an essential, if not the essential, part of the invention described in the specification. [Emphasis added.]
[49, p. 148-151] As stated, the Federal Court of Appeal applied the "purposive construction" approach to claims construction in O'Hara, supra, and, with respect, I think it was correct to do so. The appellants' argument that the principle of purposive construction is wrong or applies only to infringement issues must be rejected for a number of reasons:
(a) While Catnic, supra, dealt with infringement, the court had first to determine the scope and content of the plaintiff's invention. Lord Diplock was careful to relate his discussion of the "essential" features to the wording of the claims. It was these essential features considered without reference to specific issues of validity or infringement that constituted the "pith and marrow of the claim". He canvassed the possible existence of "any variant" of a "particular descriptive word or phrase appearing in a claim" but was careful not to link his discussion of claims construction to the particular variant in the defendant's allegedly infringing lintel. Indeed, for emphasis, he italicized the word "any" in "any variant". A patent must not of course be construed with an eye on the allegedly infringing device in respect of infringement or with an eye to the prior art in respect of validity to avoid its effect: Dableh v. Ontario Hydro,  3 F.C. 751 (C.A.), at pp. 773-74. Claims construction cannot be allowed to become a results-oriented interpretation, but there is nothing in Lord Diplock's speech that would support such an erroneous approach.
(b) Acceptance of the appellants' argument could result in a different claims construction for the purpose of validity than for the purpose of infringement (assuming purposeful construction is retained for infringement issues). However, it has always been a fundamental rule of claims construction that the claims receive one and the same interpretation for all purposes.
(c) The orthodox rule is that a patent "must be read by a mind willing to understand, not by a mind desirous of misunderstanding", per Chitty J. in Lister v. Norton Brothers and Co. (1886), 3 R.P.C. 199 (Ch. D.), at p. 203. A "mind willing to understand" necessarily pays close attention to the purpose and intent of the author.
(f) While the appellants express concern that "purposive construction" may open the door to extrinsic evidence of intent, as is the case with certain types of extrinsic evidence in the United States, neither Catnic, supra, nor O'Hara, supra, goes outside the four corners of the specification, and both properly limit themselves to the words of the claims interpreted in the context of the specification as a whole.
(h) The appellants suggest that "purposive construction" undermines the public notice function of the claims, and unfairly handicaps legitimate competition. The trial judge, they say, was able to salvage the '734 patent by narrowing the scope of the word "vane" in the earlier '803 patent by a restrictive "purposive" construction. However, purposive construction is usually criticized by accused infringers for tending to expand the written claims. In fact, purposive construction can cut either way. Here it enabled the appellants to escape infringement of the '803 patent. No doubt if the '734 patent had never been granted, the appellants would now be strongly advocating a narrow "purposive construction" of the '803 patent, and of course the respondents would just as surely be advocating the contrary position. Purposive construction is capable of expanding or limiting a literal text, as Hayhurst, supra, points out at p. 194 in words that anticipate the trial judgment in this case:
Purposive construction may show that something that might literally be within the scope of the claim was not intended to be covered, so that there can be no infringement. . .
Similarly, two other experienced practitioners, Carol V. E. Hitchman and Donald H. MacOdrum have concluded that "[a] purposive construction is not necessarily a broader construction than a purely literal one, although it may be" (Hitchman and MacOdrum, "Don't Fence Me In: Infringement in Substance in Patent Actions" (1990), 7 C.I.P.R. 167, at p. 202).
[51, p. 152] In the present case, the appellants seek a broad interpretation of the word "vane" in the '803 patent claims. It is unusual, of course, to have accused infringers arguing for a broad interpretation of the patent claims under which they have been charged. It is equally unusual for a patent owner to be demanding a narrow interpretation. The unusual role reversal is dictated by the appellants' desire to broaden the '803 patent to set up their argument for the invalidity of the later '734 patent. They contend that the plain unvarnished meaning of the word "vane" standing on its own in claims 1 and 2 of the '803 patent must, as a matter of language, include both flexible vanes and rigid vanes and that there is no call or entitlement to supplement the verbal analysis by reference to "purpose" or anything else. They plead in aid the "nose of wax" metaphor offered in the last century by the U.S. Supreme Court:
Some persons seem to suppose that a claim in a patent is like a nose of wax which may be turned and twisted in any direction, by merely referring to the specification, so as to make it include something more than, or something different from, what its words express. . . . The claim is a statutory requirement, prescribed for the very purpose of making the patentee define precisely what his invention is; and it is unjust to the public, as well as an evasion of the law, to construe it in a manner different from the plain import of its terms. [White v. Dunbar, 119 U.S. 47 (1886), at pp. 51-52, per Bradley J.]
[52, p. 152-153] I have already given my reasons for concluding that to the extent the appellants are arguing for a simple "dictionary" approach to construction of the '803 claims, it must be rejected. In Western Electric Co. v. Baldwin International Radio of Canada,  S.C.R. 570, the Court cited earlier authority dealing with the word "conduit" as used in a patent claim. Duff C.J. at p. 572 accepted the proposition that "[y]ou are not to look into the dictionary to see what 'conduit' means, but you are to look at the specification in order to see the sense in which the patentees have used it". In Consolboard, supra, as mentioned, Dickson J. considered that the whole of the specification (including the disclosure and the claims) should be looked at "to ascertain the nature of the invention" (p. 520). To the same effect is the statement of Taschereau J. in Metalliflex Ltd. v. Rodi & Wienenberger Aktiengesellschaft,  S.C.R. 117, at p. 122:
The claims, of course, must be construed with reference to the entire specifications, and the latter may therefore be considered in order to assist in apprehending and construing a claim, but the patentee may not be allowed to expand his monopoly specifically expressed in the claims "by borrowing this or that gloss from other parts of the specifications".
More recently, Hayhurst, supra, at p. 190, cautioned that "[t]erms must be read in context, and it is therefore unsafe in many instances to conclude that a term is plain and unambiguous without a careful review of the specification". In my view, it was perfectly permissible for the trial judge to look at the rest of the specification, including the drawing, to understand what was meant by the word "vane" in the claims, but not to enlarge or contract the scope of the claim as written and thus understood.
[53, p. 153-154] A second difficulty with the appellants' dictionary approach is that it urges the Court to look at the words through the eyes of a grammarian or etymologist rather than through the eyes and with the common knowledge of a worker of ordinary skill in the field to which the patent relates. An etymologist or grammarian might agree with the appellants that a vane of any type is still a vane. However, the patent specification is not addressed to grammarians, etymologists or to the public generally, but to skilled individuals sufficiently versed in the art to which the patent relates to enable them on a technical level to appreciate the nature and description of the invention: H. G. Fox, The Canadian Law and Practice Relating to Letters Patent for Inventions (4th ed. 1969), at p. 185. The court, writes Dr. Fox, at p. 203, must place itself in the position of some person acquainted with the surrounding circumstances as to the state of the art and the manufacture at the time, and making itself acquainted with the technical meaning in that art or manufacture that any particular word or words may have.
See also D. Vaver, Intellectual Property Law (1997), at p. 140. Knowledge of purpose is one of the important attributes the skilled worker brings to the exercise, as was made clear in Burton Parsons Chemicals, Inc. v. Hewlett-Packard (Canada) Ltd.,  1 S.C.R. 555, a case that concerned the validity of a chemical patent. The invention was a type of conductive cream to be smeared on bits of the human body for the purpose of making electro-cardiograms and the like. The mixture was of no fixed composition. The essential invention was "to combine a highly ionizable salt with an aqueous emulsion" (p. 564). It was put in evidence that hundreds, if not thousands, of substances would fit the description, including some that would be toxic or irritating to the skin. A toxic "conductive cream" would not be a useful therapeutic tool, and it was alleged on that account that the patent lacked utility and was invalid. These objections were swept away by Pigeon J. who held that the notional skilled workman would understand perfectly well the purpose of the combination and could therefore be expected to apply the teaching of the patent by sensibly choosing components suitable for that purpose (p. 563):
While the construction of a patent is for the Court, like that of any other legal document, it is however to be done on the basis that the addressee is a man skilled in the art and the knowledge such a man is expected to possess is to be taken into consideration. To such a man it must be obvious that a cream for use with skin contact electrodes is not to be made up with ingredients that are toxic or irritating, or are apt to stain or discolour the skin.
Burton Parsons is a pre-Catnic instance of purposive construction where, as in Catnic itself, the skilled addressee made sense and purpose of the words used in the claim by deploying the common knowledge of someone in that position. It is through the eyes of such a person, not an etymologist or academic grammarian, that the terms of the specification, including the claims, must be read.
[54, p. 154-155] The argument in this case turns on the meaning of the expression "outwardly extending substantially vertically oriented vanes" (emphasis added). All parties agree that the '803 specification, including claims, is silent on the type of vane (rigid or flexible) to be used in the lower oscillating portion of the agitator, except that the drawing of the preferred embodiment of the invention appended to the patent specification appears to show rigid vanes. "Reference to the patent drawings will sometimes clarify what is meant by a claim": Hayhurst, supra, at p. 190; see also Fox, supra, at p. 220. The drawing is of limited help but hardly conclusive because the '803 disclosure makes it clear that the drawing represents a preferred embodiment but does not necessarily exhaust the invention. The issue for the trial judge, accordingly, was whether, at the date of issuance of the '803 patent, a person skilled in the art of clothes washing machines would have understood from a reading of the claims, together with any definitional assistance from the rest of the specification, that "vanes" must be of a particular type, and if so which type, rigid or flexible.
[55, p. 155] I say "at the date of issuance of the '803 patent" because some cases suggest that the claims ought to be construed in light of the relevant knowledge at the earlier date of the invention: Ernest Scragg & Sons Ltd. v. Leesona Corp. (1964), 26 Fox Pat. C. 1 (Ex. Ct.), per Thorson P., at p. 43, or on the date the patent application was filed: AT&T Technologies, Inc. v. Mitel Corp. (1989), 26 C.P.R. (3d) 238 (F.C.T.D.), at p. 260. The possible choices of the priority date (where a Canadian application is based on a foreign filing), the Canadian filing date, the publication date or the issuance (or "grant") date, have created some uncertainty: Abbott Laboratories, Ltd. v. Nu-Pharm Inc. (1998), 78 C.P.R. (3d) 38 (F.C.T.D.), at p. 50. In the case of pre-October 1989 patent filings in Canada, one at least had the comfort of knowing that the date of publication and the date of issue were the same. For the reasons given in the accompanying decision in Free World Trust v. Électro Santé Inc.,  2 S.C.R. 000, 2000 SCC 66, at para. 54, my view is that the language of a patent should be construed as of the date of publication, which in the case of this pre-1989 patent was, to repeat, the date of issue: Western Electric, supra, at p. 582, per Duff C.J.; Burton Parsons, supra, per Pigeon J., at p. 560 ("la date de la délivrance du brevet" in the more specific French language text); Consolboard, supra, at p. 523; Fox, supra, at pp. 206-7. The critical date is important here because the appellants' double patenting argument presupposes that when the '734 patent was issued on February 17, 1981 it was obvious and uninventive to substitute flex vanes for rigid vanes on a dual action agitator. The obviousness argument would have been more tenuous as of the date of the invention almost 7 years earlier ("at least as early as June 5, 1974"), or even the date of the filing of the '734 patent application in Canada (May 27, 1977).
[56, p. 155-156] Under the new Patent Act (S.C. 1993, c. 15, s. 28), the critical date would be the date of publication which, pursuant to s. 10, would be no earlier than 18 months after the effective date of the application unless abridged with the approval of the applicants. The "effective date" in the case of a Canadian patent application based on a foreign patent application would be its priority date or the filing date of the international application. The fact the patents at issue in this case took 4 to 5 years from Canadian filing to Canadian issuance underlines the significance of the new accelerated 18-month "laid open" date.
[57, p. 156] The third and most important obstacle to the appellants' dictionary approach is that it was not in fact consistent with the testimony of their own expert. The parties called three experts. The role of the expert was not to interpret the patent claims but to put the trial judge in the position of being able to do so in a knowledgeable way.
[58, p. 156] The trial judge accepted the view of the expert called by the appellants, a retired Maytag engineer named Mr. John Mellinger, who testified that the word "vane" in claim 1 would be understood by the skilled reader of the '803 patent as a reference to a rigid vane:
And the vanes that were disclosed by Mr. Platt [applicant for the '803 patent] at that time were rigid vanes at the bottom. That was all that he really referred to, it's already pictured, didn't describe anything else.
[60, p. 156] As is discussed later, the trial judge rejected Mr. Mellinger as a person skilled in the art of "dual action" machines, and it may therefore be thought somewhat inconsistent for him to have accepted Mr. Mellinger as a skilled worker for the purpose of claims construction of a "dual action" patent. However, in light of the fact that none of the experts called by any of the parties interpreted the patent as teaching the use of flex vanes, the expert evidence left it open to the trial judge to conclude that the '803 patent specification taught rigid vanes, and that the '803 claims should be so construed.
[66, p. 158] There is, however, a second branch of the prohibition which is sometimes called "obviousness" double patenting. This is a more flexible and less literal test that prohibits the issuance of a second patent with claims that are not "patentably distinct" from those of the earlier patent. In Commissioner of Patents v. Farbwerke Hoechst Aktiengesellschaft Vormals Meister Lucius & Bruning,  S.C.R. 49, the issue was whether Farbwerke Hoechst could obtain a patent for a medicine that was a diluted version of a medicine for which it had already obtained a patent. The claims were neither identical nor conterminous. Judson J. nevertheless held the subsequent patent to be invalid, explaining at p. 53:
A person is entitled to a patent for a new, useful and inventive medicinal substance but to dilute that new substance once its medical uses are established does not result in further invention. The diluted and undiluted substance are but two aspects of exactly the same invention. In this case, the addition of an inert carrier, which is a common expedient to increase bulk, and so facilitate measurement and administration, is nothing more than dilution and does not result in a further invention over and above that of the medicinal itself. [Emphasis added.]
[70, p. 159-160] The trial judge initially accepted the evidence of the appellants' expert, Mr. John Mellinger (whose testimony the trial judge found "enlightening and trustworthy" (p. 158)) that there would be no novelty in the use of flex vanes instead of rigid vanes but in the end rejected it because of Mr. Mellinger's lack of "dual action" experience. The trial judge said (at pp. 178, 184-85 and 196):
The evidence of Mr. Mellinger is that, since Maytag's unitary action agitators with flex vanes were already on the market with commercial success, their use on the lower oscillating portion of a dual action agitator could not be considered a novel use.
. . .
I must concede that, at first, I was convinced, on the basis of Maytag's positive experience with flex vanes, that it would have been obvious to appropriate Maytag's flex vanes for use on a dual action agitator.
. . .
Mr. Mellinger admittedly had no experience with dual action agitators. Mr. Pielemeier had a lot, and was involved in product development at the time of their invention. Whose opinion evidence as to what the notional skilled technician would have thought about flex vanes on dual action agitators is to be preferred? Why, Mr. Pielemeier's is, as he has the knowledge that would better support an opinion about dual action agitation. Mr. Mellinger's opinion, though very interesting, clearly is not supported by knowledge about dual action agitation.
Mr. Pielemeier was an engineer who had been employed by the respondent Whirlpool Corporation for 15 to 20 years at the material time. He had laboured in the respondent's product development department, and had "worked with the inventors of the patents before this Court" (trial judgment, at p. 158). Someone with Mr. Pielemeier's connection to the respondents, burdened as he is with inside information, is not a very satisfactory proxy for the "ordinary worker". He is a skilled addressee but he is not operating on the basis of common knowledge in the trade. The patent claims were not addressed by Whirlpool's research engineers to their colleagues in Whirlpool's product development group. The patent claims were necessarily addressed to the wider world of individuals with ordinary skills in the technology of clothes washing machines. As Aldous L.J. observed in Beloit Technologies Inc. v. Valmet Paper Machinery Inc.,  R.P.C. 489 (Eng. C.A.), at p. 494:
The notional skilled addressee is the ordinary man who may not have the advantages that some employees of large companies may have. The information in a patent specification is addressed to such a man and must contain sufficient details for him to understand and apply the invention. It will only lack an inventive step if it is obvious to such a man. [Emphasis added.]
Dickson J. placed the same emphasis on "ordinariness" in Consolboard, supra, at p. 523:
The persons to whom the specification is addressed are "ordinary workmen", ordinarily skilled in the art to which the invention relates and possessing the ordinary amount of knowledge incidental to that particular trade. The true interpretation of the patent is to be arrived at by a consideration of what a competent workman reading the specification at its date would have understood it to have disclosed and claimed.
[78, p. 163] The trial judge held that the intermittent claims and the continuous claims "are neither inclusive nor exclusive of each other" (pp. 175-76). He said they included (at p. 176):
. . . a "continuously intermittent" motion, where during the operation of the machine, the motion of the upper auger may continuously be driven or rotated in intermittent pauses or spurts. . . . As long as the movement is not sporadic, it may very well have been contemplated to fall within the scope of the claims of the invention".
[79, p. 163] This cannot be correct. The claims clearly differentiate between two modes of operation. Claims 5 and 6 are identical except that the former speaks of intermittent drive and the latter of continuous drive. If the two claims are identical in other respects, one infers on a purposive construction that the claims were intended to describe alternative drive systems. It is well understood that "[w]here one claim differs from another in only a single feature it is difficult to argue that the different feature has not been made essential to the claim": Hayhurst, supra, at p. 198; see also Jamb Sets Ltd. v. Carlton (1963), 42 C.P.R. 65 (Ex. Ct.), at p. 73, aff'd (1965), 46 C.P.R. 192 (S.C.C.); and Submarine Signal Co. v. Henry Hughes & Son, Ld. (1931), 49 R.P.C. 149 (Eng. C.A.), at p. 174. The only difference between claims 5 and 6 is that claim 6 replaces the word "intermittently" with "continuously". Clearly, claims 6, 8 and 14 specify that for an intermittent drive means, there is substituted a drive means that continuously rotates the auger. While it is true, as the trial judge observed, that for the patent as a whole "both intermittent and continuous drive means are envisaged" (p. 176 (emphasis added)), claims 6, 8 and 14 clearly specify a continuous drive and therefore will only be infringed by a machine that continuously drives the auger. The trial judge essentially found infringement of the continuous claims by conflating them to encompass the intermittent claims.
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