Stonehouse v. Batco Manufacturing Ltd.

Stonehouse v. Batco Manufacturing Ltd.
Court (s) Database
Federal Court Decisions
Date
2004-12-22
Neutral citation
2004 FC 1767
File numbers
T-153-01
Decision Content
Date: 20041222
Docket: T-153-01
Citation: 2004 FC 1767
Ottawa, Ontario, the 22nd day of December 2004.
Present: THE HONOURABLE MR. JUSTICE SHORE
BETWEEN:
ROSS STONEHOUSE
Plaintiff and
Defendant by Counterclaim
and
BATCO MANUFACTURING LTD. and
AG GROWTH INDUSTRIES INC.
Defendants and
Plaintiffs by Counterclaim
I N D E X
Page Para. Topic
3 2 Judicial Procedures
5 9 INTRODUCTION (structure of the decision)
6 10 Historical Note
7 13 (a) Background
8 16 (b) Development of the Stonehouse Conveyor
10 27 (c) Ownership
13 37 (d) The Specification
15 45 (e) The Claims
17 52 The Defendants' Pit Stop Conveyor
19 57 Non-Infringement
23 73 Defence
33 98 Evidence
35 104 Subject Matter
38 114 ISSUES
39 115 Remedies
40 119 LEGISLATION
41 120 ANALYSIS
43 124 Teaching of the Patent
44 127 Ordinarily Skilled in the Art
44 129 Principles of Construction
46 135 Infringement
50 150 Validy of Patent
51 152 Anticipation
53 155 Anticipation by prior publication
54 157 Anticipation by prior use
55 161 Obviousness
59 168 Ambiguity, Insufficiency of the Claim's Lack
of Essential Elements
59 170 Sufficiency of Claim
60 172 Ambiguity
60 173 Allegations that the invention claims are broader
than the inventor made and disclosed
61 176 Utility
63 182 CONCLUSION
63 182 JUDGMENT
REASONS FOR JUDGMENT AND JUDGMENT
[1] After expert evidence, it's the judgment's call, is there infringement or none at all?
And, the patent does it fall, or is it valid after all?
JUDICIAL PROCEDURES
[2] Mr. Ross Stonehouse (plaintiff) sought a declaration of infringement, an injunction and damages or accounting for profits for the alleged infringement of Canadian Patent No. 2,123,257 ('257 Patent).
[3] The '257 Patent relates to an invention entitled "Conveyor for Particulate Materials"; it was filed May 10, 1994. It was open for public inspection on December 16, 1994; and was granted to the plaintiff inventor on February 2, 1999. The patent expires May 10, 2014. A patent on the same invention was filed in the United States in respect of the drive-over conveyor invention, establishing a priority date "claim date" of June 15, 1993.
[4] The statement of claim provided the following summary of the invention:
The said patent relates to an invention respecting an apparatus being a conveyor for particulate material comprising a conveyor duct, a hopper section and a feed end of the duct, a continuous belt movable longitudinally of the duct and the hopper so as to transport the particulate material deposed in the hopper section into and along the duct, all as more particularly described in the specification of the said patent and claimed in each of the claims thereof.
[5] The abstract and claims of the patent can be found in Schedule "A" (of the Further Amended Statement of Claim attached as Appendix "1" to these Reasons).
[6] The plaintiff alleged that the defendant, Batco Manufacturing Ltd. (Batco) has, without the consent of the plaintiff, since in or about 1996, continuously been in Canada, making, constructing, using, vending and selling to others a drive-over conveyor system, not being that of the plaintiff, which the defendant, Batco Manufacturing Ltd. calls a "Pit-Stop Drive-Over Conveyor". (Particulars which are set out in Schedule "B" (of the Further Amended Statement of Claim attached as Appendix "2" to these Reasons).)
[7] In addition, or in the alternative, the defendant, Ag Growth Industries Inc. has without the consent of the plaintiff, since in or before 1996, continuously been, in Canada, making, constructing, using, vending and selling to others a drive-over conveyor system, not being that of the plaintiff, which the defendant, Ag Growth Industries Inc. calls a "Pit-Stop Drive-Over Conveyor". (Particulars which are set out in Schedule "B" (of the Further Amended Statement of Claim attached as Appendix "2" to these Reasons).)
[8] The defendants, plaintiffs by counterclaim, claim:
(a) a declaration that the claims of Canadian Letters Patent 2,123,257 are, and always have been, invalid;
(b) their costs of, and incidental to, this action;
(c) such further and other relief as this Court finds just.
INTRODUCTION (structure of the decision)
[9] Other than relating the history, specifications and ownership of the respective conveyors in question, what is different or unique about the Stonehouse invention, how does it compare to the Batco product and vice versa; how do both compare to other conveyors, used for the same purposes?
What, in fact, is constant and what are the variables that differentiate one conveyor and its gathering device, from another, all of which, essentially, moves and holds (in an aggregate manner) produce of an agricultural or mining nature?
Due to the intricacies, (at times, appearing minimal, nevertheless, considered significant by certain parties versed in the area), in differentiating the variables, a detailed background is provided prior to a presentation of ISSUES in the first half of the reasons of this decision. This extensive background is provided to ensure that the terms and references of the differing perceptions, as formulated by the opposing parties are, at first, clearly examined, in and of themselves; and only after this detailed backdrop, is an analysis undertaken to reach conclusions.
HISTORICAL NOTE
[10] The plaintiff, Mr. Stonehouse, is an individual residing in Erickson, British Columbia. He was a farmer for 24 years from 1968 - 1992. Since then he has managed a trailer park in Erickson. While he has taken farm management courses over the years, he has no technical engineering training.[1]
[11] Batco is a company incorporated pursuant to the laws of Saskatchewan, with a head office in Swift Current, Saskatchewan. Batco was incorporated in 1992 and has been in the business of making farm machinery since incorporation. Batco had made the Pit Stop conveyors subject to this action since 1997.[2]
[12] AG Growth was incorporated pursuant to the laws of Saskatchewan with a head office in Swift Current. Ag Growth was formed in 1996 and Batco is a wholly owned subsidiary of AG Growth. AG Growth employs the sales team, controls the marketing including advertisements and the attendance at farm trade shows for the Pit Stop Conveyor.[3]
(a) Background
[13] The invention is said to relate to conveyors for particulate material, particularly, where a belt carries material from a hopper to a duct.[4]
[14] The patent discloses that belt conveyors, in which an initial section of the belt is flat in the hopper section following which the belt is formed into a channel in the duct (conveyor tube) were well known.[5] Various means of making the transition from the flat to the inclined section were known at the time, and Mr. Stonehouse in his actual machine, adopted a set of rollers at the upper edge of the belt, as suggested to him by a maker of belt conveyors.[6]
[15] Many of these conveyors for farm use, require the vehicle carrying the material, be accurately backed up to the conveyor.[7]
(b) Development of the Stonehouse Conveyor
[16] Mr. Stonehouse conceived the idea for his invention of the drive-over conveyor in the Fall of 1992.[8]
[17] Mr. Stonehouse contacted Richard Epp at D & R Manufacturing (D & R), a small agricultural machine manufacturing business located in Fiske, Saskatchewan, about his concept in the winter of 1993, and with the assistance of D & R employees, Mr. Stonehouse began designing and building the prototype in the Spring of 1993.[9]
[18] As a condition of receiving information about the invention, D & R signed a non-disclosure agreement with Mr. Stonehouse on March 16, 1993.[10]
[19] Mr. Stonehouse assisted in the manufacture of the prototype, which was done in April and May 1993. Mr. Stonehouse provided the concept and description of the machine and D & R did the engineering and manufacturing.[11]
[20] An embodiment of the invention was first publicly displayed in prototype form at the Farm Progress Show in late June 1993.[12]
[21] In July 1993, D & R signed a manufacturing agreement by which it obtained an exclusive licence to manufacture and sell the invention, granting Mr. Stonehouse a 5% royalty on sales of the drive-over conveyors.[13]
[22] At all times, material to this action, D & R was a small company of no more than 3-10 employees.[14]
[23] The first contact with Batco, in which it became aware of the invention was June 1993, at the Farm Progress Show, when Mr. Stonehouse met Mr. Art Stenson.[15]
[24] Mr. Stonehouse filed his application for Canadian '257 Patent for his invention on May 10, 1994, claiming priority from the June 15th, 1993 United States application.
[25] On June 9, 1997, solicitors for Mr. Stonehouse wrote Batco to advise it of the issued United States and Australian patents, and the pending Canadian application. Infringement was asserted. United States lawyers for Batco wrote, asserting non-infringement of the United States patent. [16]
[26] On October 19, 1997, Furman & Kallio on the instructions of Batco, filed a protest against the '257 Patent, citing the Compton patent, US 4,813,839, also cited in this case.[17]
(c) Ownership
[27] As related above, D & R was the first licensee of the invention. It held a licence from about July 1993, in which it would manufacture and sell conveyors embodying Mr. Stonehouse's invention and pay him a 5% royalty on sales. This agreement was updated and replaced June 19, 1995.[18]
[28] In 1996, a dispute over royalties under the agreement led to the termination of the D & R agreement.[19]
[29] Mr. Stonehouse continued to market his invention and in 1997 made a deal with Meissner Tractors, Inc. which is signed July 31, 1997.[20]
[30] The Meissner deal lasted until June 1, 1998, when REM Manufacturing Ltd. assumed the position of licensee.[21]
[31] In January 2001, the REM arrangement was terminated.[22]
[32] Mr. Stonehouse negotiated a deal with Brandt Agricultural Products Ltd. without the advice of counsel intending to grant an exclusive licence. He signed a document dated December 18, 2002 in the form of an assignment of the '257 Patent to Brandt, but in which Mr. Stonehouse was paid with a royalty stream.[23]
[33] Under the terms of that document (Article 3.5), Mr. Stonehouse was obligated to carry on the patent action against Batco as the plaintiff and report to Brandt.
[34] Brandt was entitled to withhold royalties in the event that a resolution had not been reached by July 1, 2004 and could continue to do so until judgment. Royalties would only then be payable upon a finding that the '257 Patent was valid and infringed and an injunction granted. Only substantial success would entitle Mr. Stonehouse to payment of withheld royalties. Discontinuance or success by the defendant meant that no royalties would be payable after July 1, 2004.
[35] When Brandt learned that as assignee of the '257 Patent, it had to become a party to this action, it reassigned the '257 Patent back to Mr. Stonehouse and took an exclusive licence in an effort to rectify the earlier mistake by means of an agreement signed on or about May 14, 2003, but made effective as of December 19, 2002. Since there is no provision in the Patent Act,[24] for removing a mistaken document from the register, the best that could be done was to register a nunc pro tunc reassignment.[25]
[36] The defendant had Mr. Don Henry of Brandt under subpoena, and 2 _ hours of trial time had been set aside for his testimony. The defendant elected not to call him, and an inference can properly be drawn that he would not have given evidence inconsistent with that of Mr. Stonehouse.
(d) The Specification
[37] The invention is an improved version of such conveyors where the vehicle can drive-over forwardly.[26]
[38] The first aspect describes the conveyor of the invention. It is a conveyor for particulate material made up of the following parts:
(a) a conveyor tube;
(b) a hopper section at the feed (input) end of the duct (tube);
(c) a continuous belt which moves along the tube and hopper to transport the particulate material deposited in the hopper into and along the tube;
(d) the hopper has sidewalls, each sidewall having a bottom edge spaced inwardly from a respective side edge of the belt;
(e) the sidewalls are mounted for pivotal movement about a longitudinal axis at the bottom edge of a respective sidewall such that each sidewall can fold flat downwardly to allow a vehicle wheel to pass over the sidewall and hopper;
(f) the sidewalls being arranged such that each can be moved to a raised position in which the sidewall is inclined upwardly and outwardly from the bottom edge;
(g) the belt being mounted on an inner surface of the sidewalls so as to be formed into a cupped shape to thereby confine material on the belt for entry into the tube.[27]
[39] The '257 Patent discloses preferred means of operating the pivotally mounted sidewalls including:
(a) spring raising means for the sidewalls such that the sidewalls could be moved downwardly against the spring to prevent damage if impacted in a raised position;
(b) a manually operated element to flatten the sidewalls to allow them to be driven over.[28]
[40] An embodiment is described in reference to the drawings. In addition to the essential elements, it includes a description of specific means for carrying out functions of the conveyor system that would be understood to be included within the invention such as the means of providing power to the conveyor to drive the belt and means to raise the sidewalls using a spring and lever arrangement.[29]
[41] The detailed description also includes reference to a rubber flap that extends down the inside surface of the sidewalls and extends over the outside edge of the cupped belt to help seal the hopper and prevent leakage from the edge of the belt.[30]
[42] In an alternative arrangement, the belt is flat in the hopper and the bottom edges of sidewalls are inward and just above the edge of the belt so as to allow it to run freely.[31]
[43] Folding of the sidewalls in operational position upon vehicle wheel impact to prevent damage to the sidewall is described at page 7 of Schedule "A" (of the Further Amended Statement of Claim attached as Appendix "1" to these Reasons).
[44] Normal operation is described in pp. 8-9 of Schedule "A" (of the Further Amended Statement of Claim attached as Appendix "1" to these Reasons) .
(e) The Claims
[45] There are eleven claims. Two claims, Claims 1 and 2 are independent claims. The rest are dependent on one or the other of Claims 1 or 2.
[46] Claim 1 is not asserted to be infringed by Batco.
[47] Claim 2 is very similar to Claim 1 except that the belt and sidewall are arranged in such a way that the belt is mounted (slides) on an inner surface of the sidewalls, so as to be formed into a cupped shape, thereby so as to confine material on the belt for entry of the material onto the cupped section of the belt for transport along the tube.
[48] Claim 3 is a conveyor of Claim 2 where the belt is cupped so that a portion extends up an inside surface of each sidewall, but terminates below the top of the sidewall.
[49] Claim 4 is the conveyor of Claim 3 where each sidewall has a flexible sheet which extends down and over the edge of the belt to cover part of the belt. This feature would act to further seal the hopper to prevent leaks.
[50] Claim 6 is for the conveyor of any of Claims 1-5 where the raising means has a manually operable element to permit the sidewalls to stay in the folded flat position. This also means folded down to allow a truck to drive over.
[51] Claim 9 is for the conveyor of any of Claims 1-8 where the hopper includes a base member extending along the length of the belt, the sidewalls extending along the length of the base member, with the base member long enough to receive the width of a road vehicle. This means that the base has to be at least as wide as the wheel span of the truck. It must be wider than the width of the truck wheels to give some leeway for the driver to drive over it without hitting the ends. When the base is this minimum length, the sidewalls would be the full length of the base member, so that they would contain the width of the discharge element from the truck to prevent spillage during loading. The base length can be longer than this minimum, but the sidewalls do not have to extend the full length of the base in such a case. They need only extend along the base enough, where the truck is expected to drive over, to still contain the width of the discharge element of the truck to prevent spillage during loading.
The Defendants' Pit Stop Conveyor
[52] Following the creation of the portable elevated tube conveyor, Batco then built a low profile transfer conveyor. This conveyor was assigned model number 18/14 LP. With respect to the 18/14 LP, it employed a horizontal section having a low profile hopper and an incline tube.[32]
[53] In October of 1996, Batco began its development of the Pit Stop machine. Following several development stages and the creation of different prototypes, the Pit Stop took its final form in March of 1997.[33]
[54] The motivation behind the creation of the Pit Stop machine originated with the needs of farmers, who were using existing transfer conveyors, but were interested in acquiring a conveyor that they could drive over. Specifically, the farmers were interested in using a conveyor that they did not have to pull in and out from underneath trucks.[34]
[55] The defendants looked to their low profile transfer conveyor during the design of the Pit Stop machine. The defendants' first drive-over conveyors were called the 18/14 LP-DO.[35]
[56] The defendants' Pit Stop machine uses a gusset that is welded to both the hopper floor and an adjacent hinge. The purpose of the gusset is not to confine material on the belt. In regards to the Pit Stop, the gusset has several purposes. One of its functions is to keep the edge of the belt off of the hinge, as it would be damaging to the belt were it to rub on the hinge. Another function of the gusset is to make an easier transition for vehicle wheels driving over the hopper, as it protects the hinge that would otherwise be exposed to the wheel of a vehicle. Further, the flashing, which juts out over top of the belt and covers most of the belt surface above the gusset, is protected from being damaged because when a vehicle wheel drives over the hopper the gusset supports the flashing from being pressed against, and damaged by, the hinge.[36]
Non-Infringement
[57] The plaintiff advised it would not pursue infringement of Claim 1 of the Patent. This was after the plaintiff's expert, Mr. Barry Rogers, had provided two affidavits stating that Claim 1 was valid and infringed.
[58] Mr. Rogers disagreed with the plaintiff's allegation of infringement in his Statement of Claim. In particular, the plaintiff's pleading includes a claims chart that indicates that the plaintiff alleges the defendants' sidewall bottom edge is the axis of rotation.
[59] Mr. Rogers confirmed that the '257 Patent does not make any claim to a conveyor having sidewalls adjacent to the belt.[37]
[60] Mr. Rogers, admitted that the defendants' conveyor does not infringe the claims of the plaintiff's patent as those claims are written.[38]
[61] In particular, Mr. Rogers admitted that in the defendants' Pit Stop machine, the axis of rotation of the pivotal portion of the sidewall is located beside the belt. In relation to Claim 2 of the '257 Patent, which defines the bottom edge of the sidewall by its axis of rotation, the defendants' Pit Stop machine is different in that it has an axis that is beside the belt. Thus, based on the words of Claim 2, the Pit Stop machine, which has a bottom edge adjacent to the belt, is not infringing the '257 Patent.[39]
[62] Mr. Rogers agreed that if the defendants did not infringe Claim 2, they could not infringe any claim since Claim 1 was not pursued.[40]
[63] Mr. Rogers testified that the position of the bottom edge of the sidewalls in the '257 Patent is an essential element of all claims of the patent.[41]
[64] In Free World Trust v. Electro Santé Inc.,[42] Justice Binnie held that "...the ingenuity of the patent lies not in the identification of a desirable result but in teaching one particular means to achieve it. The claims cannot be stretched to allow the patentee to monopolize anything that achieves the desirable result."
[65] Determining whether a variant is non-essential and thus substitutable has also been reduced to three questions:
(i) Does the variant have a material effect upon the way the invention works? If yes, the variant is outside the claim. If no: -
(ii) Would this (i.e.: that the variant had no material effect) have been obvious at the date of publication of the patent to a reader skilled in the art? If no, the variant is outside the claim. If yes: -
(iii) Would the reader skilled in the art nevertheless have understood from the language of the claim that the patentee intended that strict compliance with the primary meaning was an essential requirement of the invention? If yes, the variant is outside the claim.[43]
[66] When the facts of the present case are applied to the above test, it is clear that the defendants' pivotal sidewall plus gusset cannot be construed to be the sidewall of the '257 Patent. First, the sidewall and gusset do have a material effect on the way the invention works. As noted above, the gusset does not pivot, does not fold flat, and the combination of the two do not seal the gap and confine material on the belt since the belt does not extend to the pivotal sidewall. Second, there is no evidence, other than a statement by Mr. Rogers which is contradicted by the defendants' expert, Mr. Craig Hanson, that it would have been obvious to the skilled person at the publication date that these two structures could be substituted. Third, the evidence is that the language of the claims make it clear that the patentee did intend that strict compliance with the position and structure of the sidewall - the primary meaning - was an essential element of the invention. The patentee is stuck with the narrow words of his own choosing.
[67] It is those words in the claim that give the ambit of the monopoly certainty and the claims must be taken to mean what they say.
[68] Mr. Rogers' opinion that the wording of the '257 Patent would not make a skilled person believe that strict compliance with "bottom edge" of the sidewall was essential, appears to be untenable, since such a construction would contradict the words of the claims. Specifically, the configuration of the sidewalls and the respective bottom edges is essential, as it is this configuration that confines material on the belt. A sidewall that is not pivotal at its bottom edge, but instead anywhere along its surface, not only does not accomplish the function and result of the '257 Patent, but also contradicts the claim language. Furthermore, there is nothing in the '257 Patent that suggests a fixed portion as well as a pivotal portion of a sidewall. A sidewall pivoting somewhere other than its bottom edge could not fold flat. The existence of a fixed portion means that part of the sidewall would not be pivotal.[44]
[69] Regarding the specific words chosen by the patentee, the court in Free World Trust held that "...if the inventor has misspoken or otherwise created an unnecessary or troublesome limitation in the claims, it is a self-inflicted wound. The public is entitled to rely on the words used provided the words used are interpreted fairly and knowledgeably".[45]
[70] As stated in Free World Trust at paragraph 57:
...the onus is on the patentee to establish known and obvious substitutability at the date of publication of the patent. If the patentee fails to discharge that onus, the descriptive word or expression in the claim is to be considered essential unless the context of the claims language otherwise dictates.
[71] The House of Lords, in a very recent decision, has commented on the issue of claim construction:
"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 document 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...
I agree with the Court of Appeal that the invention should normally be taken as having been claimed at the same level of generality as that at which it is defined in the claims. It would be unusual for the person skilled in the art to understand a specification to be claiming an invention at a higher level of generality than that chosen by the patentee...[46]
[72] After created knowledge, as was said in Free World Trust at paragraph 57:
The ambit of the monopoly would grow over the life of the patent as new substitutes are developed and absorbed into the common knowledge of the skilled worker. The inventor cannot be thought to have the necessary "intent" in relation to after-created knowledge except in the irrelevant sense of intending to reap the benefit of the maximum coverage available...
Defence
[73] This case asks the Court to define the limits of a monopoly. Batco denies that their product, the Batco Pit Stop machine, infringes the '257 Patent.
[74] Similarities abound between the case at bar and Free World Trust at paragraph 1, here Justice Binnie began his decision noting,
The principal question that arises on this appeal is the extent to which a patent monopoly protects "the substance" or "the spirit" of an invention, as distinguished from what is literally described in the written claims...
More specifically, the appellant concedes that the respondents' machine...is not precisely as described in the written claims of its patents. It says, however, that the respondents have stolen the substance of its invention...
[75] As in Free World Trust, the plaintiff, through its expert witness, Mr. Rogers, admitted that the defendants' conveyor does not infringe the claims of the plaintiff's Patent as those claims are written. In particular, Mr. Rogers agreed that if one reads the claims as written, the defendants' conveyor does not include sidewalls spaced inwardly from a side edge of the belt. The claims define the bottom edge of the sidewall as its axis of rotation, and in the defendants' conveyor, that axis of rotation is adjacent to or beside the belt, not spaced inwardly from it. Accordingly, the defendants' conveyor varies or omits an essential element of all claims of the patent. We know the location of the sidewalls is an essential element because Mr. Rogers admitted that if they were adjacent to the belt and not spaced inwardly, then there could be no infringement.
[76] Free World Trust, makes clear that there is no infringement if there is variation or omission of an essential element. As such, the defendants' conveyor is outside the ambit of the monopoly as claimed. Mr. Rogers says, however, that the defendants have infringed the "essence" of the plaintiff's invention. He admitted that there is no support anywhere in the patent for his idea of what constitutes his understanding of its "essence".
[77] It is important to note that the plaintiff's expert admitted that he did not construe the patent claims prior to rendering his opinion on infringement. In fact, he admitted that one skilled in the art would not read the patent and understand that the patentee was describing or claiming a two-piece sidewall. Yet, Mr. Rogers' infringement opinion relies on his argument that the defendants' conveyor has a two piece sidewall. He says that, while a two-piece sidewall is not claimed or described in the Patent, it nevertheless falls into the "essence" of the invention.
[78] Justice Binnie put to rest any suggestion of infringement of the "essence". Speaking for a unanimous Supreme Court of Canada bench in Free World Trust, he held:
(a) The Patent Act promotes adherence to the language of the claims.
(b) Adherence to the language of the claims in turn promotes both fairness and predictability.
(c) The claim language must, however, be read in an informed and purposive way.
(d) The language of the claims thus construed defines the monopoly. There is no recourse to such vague notions as the "spirit of the invention" to expand it further...
[79] Accordingly, a finding of infringement must be based on infringement of a patent's claims, purposively construed. The law in Canada is clear: infringement cannot be based on vague notions such as the "spirit of the invention". The claims define the monopoly.
[80] Mr. Rogers also admitted that his interpretation of sidewalls in the Patent was based on his review of the defendants' conveyor. The Supreme Court of Canada in Whirlpool Corp. v. Camco Inc.,[47] held that patent construction cannot be done with an eye on the infringing machine. Nevertheless, referring to the defendants' conveyor, Mr. Rogers gave an opinion that a skilled person would know that the defendants' welded gusset (which the defendants' expert, Mr. Hanson, considered to be part of the hopper floor) could be substituted for the pivotal sidewall in the claims. It is the plaintiff's burden to establish known and obvious substitutability at the date of publication of the patent (Free World Trust). However, substitutability cannot be established for at least the following reasons:
(a) First, Mr. Rogers admitted that the gusset works in a different way from the sidewall in the Patent. The gusset does not pivot, and does not fold flat. Further, Mr. Rogers' interpretation requires a two-piece sidewall which is not disclosed or claimed. Even if one were to agree with him that the gusset confines material on the belt, it does so in a different way.
(b) Second, the gusset does not achieve the same result as the sidewall in the Patent. In Claim 2 of the Patent, the belt is mounted on the sidewalls to be formed into a cupped shape "so as to confine material on the belt". The defendants' expert, Mr. Hanson, confirmed that the belt and the gusset do not act to confine material on the belt; the rubber flashing performs this function. If one removes the gusset, the flashing continues to confine material on the belt. This was not shaken on cross examination. Indeed, photos of the defendants' conveyor show that the belt does not seal the gap between the sidewall and the floor and material gets lodged into the gap. Even on Mr. Rogers' interpretation, the gusset achieves a different result.
(c) Third, even if the above two hurdles were overcome, the plaintiff has the burden to show that, "...on a purposive construction of the words of the claim it was clearly not intended to be essential...", that is, the patentee did not intend strict compliance (Free World Trust). In fact, the evidence is just the opposite. Both experts agreed that the great amount of detail the patentee put into the specific construction and position of the sidewalls indicates that the patentee intended the sidewall position and construction to be essential. The "bottom edge" of the sidewall is specifically defined in the claims as the axis of rotation. The patentee intended strict compliance with his chosen words.
[81] In contrast to Mr. Rogers, the defendants' expert, Mr. Hanson, first construed the Patent prior to considering infringement or validity. Mr. Hanson found the patent claims to be unambiguous. He referred to the patent description as well and he found that it supported the meaning he gave to the claims by reading the claims themselves. Mr. Hanson gave a purposive construction to the claims and found that none of the patent claims were infringed.
[82] Mr. Rogers admitted that the defendants' conveyor does not infringe the claims of the plaintiff's Patent as those claims are written.[48]
[83] In particular, Mr. Rogers admitted that in the defendants' Pit Stop machine, the axis of rotation of the pivotal portion of the sidewall is located beside the belt. In relation to Claim 2 of the '257 Patent, which defines the bottom edge of the sidewall by its axis of rotation, the defendants' Pit Stop machine is different in that it has an axis that is beside the belt. Thus, based on the words of Claim 2, the Pit Stop machine, which has a bottom edge adjacent to the belt, is not infringing the '257 Patent.[49]
[84] Mr. Rogers agreed that if the defendants did not infringe Claim 2, they could not infringe any claim since Claim 1 was not pursued.[50]
[85] Mr. Rogers testified that the position of the bottom edge of the sidewalls in the Patent is an essential element of all claims of the Patent.[51]
[86] With respect to the gusset in the Pit Stop machine, it cannot be considered to be a sidewall. The '257 Patent requires that for something to be a sidewall it must pivot. As well, the gusset in the Pit Stop does not perform the same function as a sidewall in the '257 Patent. The rubber flashing in the Pit Stop covers the angled portion of the belt such that no material actually rides on the angled portion.[52]
[87] Mr. Rogers agreed that even when the Pit Stop sidewall is fully raised, there is still a gap between the belt and the pivotal section of the sidewall. In other words, the belt in the Pit Stop is not positioned over the gap between the pivotal sidewall and the gusset.[53]
[88] Defendants showed a photo of the Pit Stop with the sidewalls raised showing that materials such as corn or grain gets lodged inside this gap between the pivotal sidewall and the gusset. Rubber flashing covers this gap to confine material on the belt and prevent leakage; the belt does not cover the gap at the pivot point.[54]
[89] If it were not for the rubber flashing in the defendants' conveyor, material would fall off the side of the belt and into the gap between the gusset of the hopper floor and the Pit Stop sidewall.[55]
[90] Mr. Rogers, for the first time in his reply affidavit, said that a portion of the defendants' hinge lay under the gusset which lay under the belt and thus infringed the Patent claims. Mr. Rogers admitted that this was not part of his infringement opinion in chief, and further admitted that, even if one considered this, the axis of the sidewall is still adjacent to the belt. Furthermore, the 1/8" of the hinge that is under the gusset cannot be raised up so as to confine material.[56]
[91] With respect to the 1/8" of the Pit Stop hinge, Mr. Hanson said that a person skilled in the art would not agree that this was the bottom edge of the sidewall. The '257 Patent removes any doubt by explicitly stating that the bottom edge of the sidewall is its axis of rotation. The 1/8" section of the hinge under the gusset does not in any way fulfill the purpose of the sidewall which is to cup the belt and prevent leakage. In fact, a gap remains and is not sealed by the belt.[57]
[92] The hinge tube does not confine material on the belt. Indeed, the hinge tube actually provides a gap to permit leakage between the belt and the sidewall, thus having a different function and result than the invention in the '257 Patent. In other words, the Pit Stop omits the crucial sealing aspect of the '257 Patent. Further, because of this gap, it was necessary for the Pit Stop to employ a flexible sheet to cover the hinge, which effectively eliminates any argument that the belt is cupped by the 1/8 of an inch of the hinge. Also, the hinge assembly is constructed with alternating hinge tubes that are welded to the hopper frame, it is not logical for a particular point on the belt to be travelling over the sidewall only at some times and not at others. Furthermore, it would not be logical to consider that the hinge assembly, which includes tubes that are welded to the hopper frame, is a part of the sidewall.[58]
[93] A skilled person would understand that the hinge and the sidewall are distinct elements, even if the hinge is welded to the sidewall. With respect to the door and hinge analogy, the door component is certainly not part of the hinge component - the two are distinct elements. Even where the hinge has been screwed or welded to the door, they remain distinct elements. If one were to construe the hinge and the door as being one element, then one would have to also consider an endless number of elements, such as the frame of the door, as being part of that one distinct element. It would be a never-ending element. Indeed, when a door is opened, half of the hinge does not move with the door and remains stationary.[59]
[94] Mr. Rogers confirmed on cross examination that the Patent disclosed and claimed an invention that cupped the belt by operation of placing the two pivoting sidewalls inward from the side edges of the belt. When the sidewalls are pivoted in an upward position, the belt is thereby cupped.[60]
[95] However, Mr. Rogers then argued on cross examination that a conveyor that included any means for cupping the belt infringed the Patent. For example, a conveyor with a cupped hopper bottom infringed the claims of the Patent even if the belt was nowhere near the sidewall axis. This was illustrated by the drawings at Exhibits D-11, D-12 and D-13, one which showed, for example, a conveyor having a hopper bottom having a slight concave arc shape. The belt was positioned in the middle of the hopper and well inward from the axis of the pivotal sidewalls. Mr. Rogers felt that the entire cupped hopper floor was in fact the "fixed portion" of the sidewall and, since the belt travelled along the centre of the hopper floor, the structure would infringe the Patent claims because the belt was over the "stationary" portion of the sidewall. Mr. Rogers' interpretation was based on his understanding of the "essence" of the invention.[61]
[96] Mr. Rogers admitted that the exposed portion of the travelling belt in the defendants' conveyor is "essentially flat". The rubber flashing covers the cupped portion of the belt on the gusset.[62]
[97] Mr. Rogers agreed there was no support anywhere in the Patent for a cupped hopper floor; indeed, the Patent discloses and teaches a flat hopper floor and requires sidewalls that can "fold flat".[63]
Evidence
[98] Although the views of the experts differed considerably, the Court found the expert testimony most helpful. The knowledge and integrity manifested by Mr. Rogers for the plaintiff and Mr. Hanson for the defendants were very much appreciated. These experts assisted the Court in reaching its own construction of the claims of the Patent and its findings with respect to infringement and to validity.
[99] Ultimately, it is the Court, and the Court alone, which is tasked with construing the patent. This principle has been stated many times in Canadian law, but it bears repeating. The Court is not bound by this evidence to make its findings. This is said in respect of the construction of the claims and to the finding of infringement or that of validity. Several cases have made this point. In Nekoosa Packaging Corp. v. AMCA International Ltd.,[64] the Federal Court of Appeal wrote as follows:
While the question of admissibility of expert evidence on ultimate issues is not before us, it is of paramount significance to appreciat