Docket: A-479-15
Citation: 2017 FCA 225
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CORAM:
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PELLETIER J.A.
RENNIE J.A.
WOODS J.A.
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BETWEEN:
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CIBA SPECIALTY
CHEMICALS WATER TREATMENTS LIMITED
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Appellant
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and
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SNF INC.
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Respondent
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REASONS FOR
JUDGMENT
PELLETIER J.A.
INTRODUCTION
[1]
This is an appeal from a decision of the Federal
Court, reported as 2015 FC 997 (Reasons), in which the Court found that
Ciba Specialty Chemicals Water Treatments Limited’s (Ciba) Canadian Patent CA 2
515 581 (the ‘581 patent) was invalid due to obviousness. The action for a
declaration of invalidity was brought by SNF Inc. (SNF), Ciba’s competitor in the
industrial chemical business.
[2]
SNF’s action for a declaration of invalidity of
the ‘581 patent was brought on the basis of obviousness, anticipation by prior
art and prior use, insufficiency, overbreadth and the presence of false and
misleading statements in the application for the patent. The Federal Court
found that the allegations of anticipation, insufficiency and overbreadth were
not made out. The Court also found that the patent application contained false
and misleading statements but because they were not material, the patent was
not void pursuant to section 53 of the Patent Act, R.S.C. 1985, c.
P-4 (the Act) on that account. As a result, the only successful ground of
invalidity was obviousness.
[3]
I believe that the Federal Court erred in its
articulation and application of the Windsurfing/Pozzoli framework but it
nonetheless came to the right conclusion on the question of obviousness. As
this conclusion is sufficient to dispose of the appeal, I do not propose to
deal with the other grounds raised by the parties.
FACTS
[4]
Like most industries, the mining industry must
deal with the waste created by its operations. One of those waste products is a
water-borne stream of dispersed particulate matter, commonly referred to as
slurry. Mine operators have economic and environmental incentives to recycle
the water and to minimize the land area required to dispose of the particulate
matter. The ‘581 patent addresses these issues.
[5]
Water can be separated from the particulate
matter in a slurry using a device known as a paste thickener, a cone-shaped
vessel into which slurry is pumped and allowed to stand. The particulate matter
settles out leaving a liquid at the surface which can be removed and reused.
The settled particles at the bottom of the vessel together with the remaining
water (the underflow) can then be pumped out to a deposition area where the
water will escape through sedimentation, drainage and evaporation. The
dewatered particulate matter, known as tailings, can then be managed on the
site.
[6]
This process can be improved by the use of a
class of chemicals known as flocculants. The flocculants in issue in the case
are water-soluble polymers. Flocculants cause particles to aggregate into flocs
(essentially, larger particles) which can further aggregate into permeable
structures which allow water to escape. Flocculants added to the slurry in a
paste thickener can accelerate the separation of water from the particulate
matter and improve the quality of the recovered water.
[7]
The ‘581 patent deals with the treatment of the
underflow during its transfer from its initial treatment, in a paste thickener
for example, to a deposition area. The lower the amount of particulate matter
in that water, the more suitable it is for reuse in mining operations and the
less harmful it is if it escapes into the surrounding area. The less water
there is mixed with the particulate matter, the faster it will consolidate and
solidify.
[8]
The objectives of dewatering and solidification
can be achieved if upon discharge in the deposition area, the slurry solidifies
(“rigidifies”) quickly (by the escape of water),
and if fine and coarse particles form a homogeneous mixture. This homogeneous
mixture improves the quality of the released water because fine particles are
retained in the homogenous mixture. It is also better adapted to support the
weight of subsequent deposits. The rapid solidification of the material
minimizes the extent to which it flows so that stacks of material can be
created which reduce the amount of land required to accommodate tailings.
[9]
The patent teaches that attempts have been made
to achieve these objectives through the treatment of the feed to the tailings
dam using a flocculant. However, these attempts were unsuccessful as these
treatments were applied at conventional doses which produced little or no
benefit. The ‘581 patent describes the prior art, in particular patent no.
WO-A-0192167 (the Gallagher patent) which teaches the introduction of particles
of water-soluble polymer into the tailings feed. This allows the treated slurry
to retain its fluidity while being pumped to a deposition area but to “rigidify” i.e. solidify upon standing. The ‘581
patent states that the Gallagher patent emphasizes the use of water-soluble
polymer particles and alleges that the use of aqueous solutions of dissolved
polymer is ineffective. The latter statement, which the Federal Court found to
be untrue, was the basis of the claim that the ‘581 patent was void because of
false and misleading statements in the application for the patent.
[10] The ‘581 patent describes a process which is said to be an
improvement on the prior art. The invention is described under various aspects,
one of which is sufficient to illustrate the nature of the invention:
[…] there is provided a process of
rigidifying a material whilst retaining the fluidity of the material during
transfer, in which the material comprises an aqueous fluid with dispersed
particulate solids that is transferred as a fluid to a deposition area, then
allowed to stand and rigidify, by combining with the material during transfer
an effective rigidifying amount of an aqueous solution of a water-soluble
polymer, said water-soluble polymer having an intrinsic velocity of at least 5 dl/g
[5 daltons/gram] (measured in 1 M NaCl at 25° C).
‘581 patent at page 7b lines 3-10.
[11] The patent recites that it has been unexpectedly found that the
addition of an aqueous solution of polymer to the slurry mixture during
transfer does not cause instant rigidification or any substantial settling of
the particulate matter while it is being transferred.
[12] The patent also states that the flow characteristics of the treated
material as it rigidifies are important:
[…] since once the material is allowed to
stand it is important that flow is minimised and that solidification of the
material proceeds rapidly. If the material is too fluid then it will not form
an effective stack and there is also a risk that it will contaminate water
released from the material. It is also necessary that the rigidified material
is sufficiently strong to remain intact and withstand the weight of subsequent
layers of rigidified material being applied to it.
‘581 patent at page 15 lines 12-19.
[13] The patent goes on to state that it is not possible to achieve the
objectives sought by adapting the flocculation step in the paste thickener and
that it is essential to treat the material formed as an underflow in the paste thickener.
This allows the treated material to rigidify effectively without compromising
the fluidity during transfer.
[14] That, in summary form, is the nature of the invention described in
the ‘581 patent and the relevant teachings of the patent.
THE DECISION UNDER APPEAL
[15] Unlike the usual scenario in which a patent holder sues a competitor
for infringement of its patent and is met by a counterclaim alleging invalidity
of the patent, this proceeding began as an action for a declaration of
invalidity of the ‘581 patent. Ciba counterclaimed alleging infringement but
that allegation was settled along the way so that the only issue before the
Federal Court was the validity of the ‘581 patent.
[16] In order to avoid repetition, I will deal with the details of the
Federal Court’s analysis in the course of my own analysis. At this stage, I
will simply highlight the Court’s conclusions on various issues so as to provide
an overview of its reasoning.
[17] The Federal Court began its reasons by providing the factual context
of the invention. It then provided a summary of the evidence of the witnesses,
both lay witnesses and experts. In the course of doing so, it offered its
critique of the witnesses’ evidence. In particular, the Federal Court compared
the evidence of SNF’s experts, Dr. Klein and Mr. Hyatt, to Ciba’s expert,
Dr. Farrow. In the end, the Court found that it would treat Dr. Farrow’s
evidence with caution for reasons which will be explained later in these
reasons.
[18] The next step in the Federal Court’s analysis was the identification
of the person skilled in the art to which the invention pertains (the Skilled
Person). The Court then set out the common general knowledge which the Skilled
Person would have at their disposal. The key issue in that area was whether
in-line addition of polymer was part of the common general knowledge. Based
upon the Court’s view that SNF’s experts “were closer
to the Common General Knowledge [than Dr. Farrow] given their greater field
experience”, it found that in-line polymer addition was part of the
common general knowledge at the material time: Reasons at paragraph 123.
The Court concluded this part of its analysis by itemizing a number of other
aspects of the common general knowledge of the Skilled Person.
[19] The Court then construed the patent, more particularly Claim 1
upon which all other claims are dependent, either directly or indirectly.
Claims 32 and following are indirectly dependent on Claim 1 in the
sense that they are dependent upon earlier claims which are themselves
dependent upon Claim 1.
[20] The principal issue in the construction of Claim 1 was the
meaning of the words “rigidify” and “rigidification”, coined words which are neither
scientific nor technical. After canvassing the evidence of the experts, the
Federal Court concluded that rigidification meant “increasing
the yield stress of a mineral deposit rapidly whereby the flow of the deposit
is minimized and the weight of subsequent layers of like deposit is supported”:
Reasons at paragraph 163.
[21] The Court then considered the issue of anticipation—which I do not
propose to address—before turning its attention to obviousness. The Court set
out the four-step obviousness analysis (the Windsurfing/Pozzoli
framework) adopted by the Supreme Court in Apotex Inc. v. Sanofi-Synthelabo
Canada Inc., 2008 SCC 61, [2008] 3 S.C.R. 265 (Plavix).
Since it had already completed step 1 by identifying the Skilled Person
and the common general knowledge, the Court went on to the second step, namely
the identification of the inventive concept. In the Court’s view, the inventive
concept was the insight “that an effective amount of
solution addition of water soluble polymer can result in a rigidification
analogous to the deposit of a paste thickener”: Reasons at paragraph 191.
[22] The Court then asked itself if it would be obvious to the Skilled
Person that the addition of an effective amount of the polymers listed in the
patent would result in rigidified deposits. It concluded that the Skilled
Person would go directly and without difficulty to the solution of adding a
minimum dose of polymer to a tailings feed and then increasing the dosage to
achieve the desired outcome. In that sense, applying an effective amount of
polymer would have been obvious.
[23] The Court went on to say that “an effective
amount of solution addition of a water soluble polymer would have been obvious
to try”: Reasons at paragraph 196. The Court then reviewed the list
of non-exhaustive factors proposed by the Supreme Court in Plavix in
relation to the “obvious to try” test and
concluded that they were met so that the “obvious to
try” test was also met. On that basis, the Court found that ‘581 patent
was invalid for obviousness.
[24] The Court then addressed the other grounds of invalidity raised by
SNF even though its conclusion on obviousness was sufficient to dispose of the
action. As I do not intend to deal with those grounds, I will say no more about
them.
ISSUES
[25] Ciba argues that the Federal Court committed a series of cascading
errors, the earlier errors leading to subsequent errors, culminating in the
erroneous conclusion that the invention disclosed in the ‘581 patent was
obvious. Ciba alleges first that the Federal Court erred in preferring the
evidence of SNF’s experts over the evidence of its expert, Dr. Farrow. This in
turn caused the Federal Court to err in its determination of the common general
knowledge of the Skilled Person. This led to an erroneous conclusion as to the
inventive concept which in turn led to the mistaken conclusion that the ‘581
patent was invalid for obviousness. I will address each of these in turn.
[26] Since this is an appeal from a decision of the Federal Court sitting
as a trial court, the appellate standard of review applies: palpable and
overriding error for questions of fact and questions of mixed fact and law,
except for extricable questions of law for which the standard of review is
correctness: Housen v. Nikolaisen, 2002 SCC 33, [2002] 2 S.C.R. 235
(Housen).
ANALYSIS
Preference for some experts over others
[27] Ciba alleges that the Federal Court erred in preferring the evidence
of SNF’s experts, Dr. Klein and Mr. Hyatt, to that of its expert, Dr.
Farrow. The assessment of expert evidence is a question of fact, reviewable on
the standard of palpable and overriding error: Eurocopter v. Bell Helicopter
Textron Canada Ltée, 2013 FCA 219 at paragraph 74, 120 C.P.R.
(4th) 394, Halford v. Seed Hawk Inc., 2006 FCA 275 at paragraph 11,
54 C.P.R. (4th) 130. A court will fall into palpable and overriding error when
it comes to a conclusion for which there is no factual basis, or when its
reasoning is illogical or unrelated to the evidence: Mahjoub v. Canada
(Minister of Citizenship and Immigration), 2017 FCA 157 at paragraph 62,
[2017] F.C.J. No. 726 (QL).
[28] Ciba argues that the Federal Court’s preference for SNF’s experts
because they had “greater field experience” is a
palpable and overriding error. Ciba invites us to compare the experts’
qualifications and to come to our own conclusion. That is not the role of an
appellate court. Our role is to determine if there was a factual basis for the
Federal Court’s conclusion. In my view, there was such a basis.
[29] Beginning at paragraph 62 of its reasons, the Federal Court
considered the academic qualifications and the practical experience of the
experts tendered by the parties. It touched upon Dr. Klein’s practical
experience, without setting it out in detail. It found that “Klein brought an element of practicality to what was a
practical patented process”: Reasons at paragraph 71. The Court
also summarized Mr. Hyatt’s 30-year career as a vendor of process chemicals and
consultant to the mining industry. There was a basis upon which the Federal
Court could find as it did on the issue of SNF’s experts’ practical experience.
[30] Quite apart from the issue of practical experience, at paragraphs 83
to 87 of its Reasons, the Court explained why it preferred the evidence of
SNF’s experts to Dr. Farrow’s. The Court found Dr. Farrow’s evidence “less persuasive, consistent, objective and balanced than one
would reasonably expect.” It noted that on a major issue in the
construction of the patent, Dr. Farrow “advanced
different and shifting meanings” and supplied “a
result oriented interpretation”: Reasons at paragraphs 83-84.
[31] Overall, the Court found that Dr. Farrow was more of an advocate for
the patent’s validity than was appropriate, given his status as an expert. As a
result, the Court approached his evidence with grave caution.
[32] The Federal Court’s stance is consistent with the Supreme Court’s
teachings on expert witnesses:
Expert witnesses have a special duty to the
court to provide fair, objective and non-partisan assistance. A proposed expert
witness who is unable or unwilling to comply with this duty is not qualified to
give expert opinion evidence and should not be permitted to do so. Less
fundamental concerns about an expert's independence and impartiality should be
taken into account in the broader, overall weighing of the costs and benefits
of receiving the evidence.
White Burgess Langille Inman v. Abbott
and Haliburton Co., 2015 SCC 23 at paragraph 2,
[2015] 2 S.C.R. 182.
[33] The Federal Court was entitled to treat Dr. Farrow’s evidence with
the caution it did on the basis of its conclusions as to the latter’s
partiality.
The content of the common general knowledge
[34] Ciba’s primary concern in raising the issue of the expert evidence
was the difference between the parties’ experts on the question of whether the
common general knowledge attributable to the Skilled Person at the material
date included the concept of introducing polymer to a slurry “in-line” or “in-pipe”,
i.e. while it is being pumped or transferred to a tailings deposition area.
[35] At paragraph 121 of its Reasons, the Federal Court noted that SNF’s
experts were of the view that “in-line polymer
treatment of tailings was part of the Skilled Person’s Common General
Knowledge”, while Ciba’s expert Dr. Farrow disagreed. The major reason
for Dr. Farrow’s disagreement was the absence of references to in-line polymer
treatment in two publications: “The 2002 Paste and
Thickened Tailings – A Guide” and “Mineral
Processing Plant Design, Practice and Control Proceedings (2002)”.
[36] The Federal Court held that the absence of a reference to a
particular fact in one or more publications does not disprove that fact. This
is a very context-specific observation, but in the context of the whole of the
evidence which the Federal Court had before it, it is an observation which it
was entitled to make. This did not prove that in-line polymer treatment was
part of the common general knowledge but it was sufficient to set aside the
position taken by Dr. Farrow and which continues to be advanced by Ciba.
[37] As this Court noted in Janssen-Ortho Inc. v. Novopharm Ltd.,
2007 FCA 217 at paragraph 25(3):
Not all knowledge is found in print form. On
the other hand, not all knowledge that has been written down becomes part of
the knowledge that a person of ordinary skill in the art is expected to know or
find.
[38] In this case, the Federal Court had before it the evidence of Dr. Klein
and Mr. Hyatt to the effect that in-line polymer treatment was part of the
common general knowledge and Dr. Farrow’s evidence that it was not. The Court
assessed that evidence in the context of all the evidence and its assessment of
the witnesses’ credibility and concluded that it preferred the evidence of Dr. Klein
and Mr. Hyatt.
[39] In Housen, while discussing the many reasons why appellate
courts should defer to trial courts on questions of fact, the Supreme Court
quoted with approval the following passage from R. D. Gibbens, “Appellate Review of Findings of Fact” (1992) 13:4
Advocates’ Q. 445, at page 446:
The trial judge is said to have an expertise
in assessing and weighing the facts developed at trial. Similarly, the trial
judge has also been exposed to the entire case. The trial judge has sat through
the entire case and his ultimate judgment reflects this total familiarity with
the evidence. The insight gained by the trial judge who has lived with the case
for several days, weeks or even months may be far deeper than that of the Court
of Appeal whose view of the case is much more limited and narrow, often being
shaped and distorted by the various orders or rulings being challenged.
Housen at
paragraph 14.
[40] This passage was distilled into one of the three basic principles
which the Supreme Court put forward as justifying deference to the trial
judge’s findings of fact:
The trial judge is better situated to make
factual findings owing to his or her extensive exposure to the evidence, the
advantage of hearing testimony viva voce, and the judge's familiarity
with the case as a whole. Because the primary role of the trial judge is to
weigh and assess voluminous quantities of evidence, the expertise and insight
of the trial judge in this area should be respected.
Housen at
paragraph 18.
[41] The debate on the issue of the content of the common general
knowledge demonstrates the wisdom of this principle. It is very difficult for
this Court to acquire the familiarity with the evidence which a trial judge has
developed over the course of the trial. As a result, it is unwise for us to
interfere with a trial judge’s conclusions of fact on the basis of isolated elements
of the evidence brought to our attention by counsel. These debates seldom occur
in a context in which there is no evidence on a given point. They almost always
occur where, as here, there is conflicting evidence. It is not our function,
absent exceptional circumstances, to resolve conflicts in the evidence. That is
the role of a trial judge and, so long as there is evidence to support the conclusion
and the reasoning is sound and anchored in the evidence, this Court should not
intervene.
[42] Therefore, I would not interfere with the Federal Court’s
determination that the in-line polymer treatment was part of the common general
knowledge at the material time.
Obviousness
[43] Ever since the Supreme Court adopted the Windsurfing/Pozzoli
framework for the analysis of obviousness in Plavix, it has been at the
centre of discussions of obviousness. The Windsurfing/Pozzoli framework
was elaborated in two U.K. cases, Windsurfing International Inc. v. Tabur
Marine (Great Britain) Ltd, [1985] R.P.C. 59 (C.A.), (Windsurfing),
and Pozzoli SPA v. BDMO SA, [2007] F.S.R. 37, [2007] EWCA Civ 588
(Pozzoli).
[44] In this case, the Federal Court misstated and misapplied the Windsurfing/Pozzoli
framework; in particular, it did not properly identify the proper roles of the
prior art and the common general knowledge. In the end, however, it came to the
right conclusion so that this Court’s intervention is not warranted.
[45] The elements of the Windsurfing/Pozzoli framework, as set out
in Plavix, are as follows:
1)
(a) Identify the notional "person skilled in the art";
(b) Identify the relevant common general knowledge of that person;
2) Identify the inventive concept of the claim in question or if that
cannot readily be done, construe it;
3) Identify what, if any, differences exist between the matter cited as
forming part of the "state of the art"
and the inventive concept of the claim or the claim as construed;
4) Viewed without any knowledge of the alleged invention as claimed, do
those differences constitute steps which would have been obvious to the person
skilled in the art or do they require any degree of invention?
Plavix, at
paragraph 67.
[46] In the decision before us, the Federal Court did not refer to the Supreme
Court’s elaboration of the Windsurfing/Pozzoli framework but relied
instead on the Federal Court’s summary of the latter in Eli Lilly Canada Inc.
v. Mylan Pharmaceuticals ULC, 2015 FC 125 at paragraph 158, 130
C.P.R. (4th) 116:
1) Identify the notional "person skilled
in the art" and the relevant common general knowledge of that
person;
2) Identify the inventive concept claimed in the patent;
3) Identify the differences between the common general knowledge and
the inventive concept;
4) Do those differences require a degree of invention, or are they more
or less self-evident?
Reasons, at
paragraph 182.
[47] This formulation introduces an error in the framework when it
substitutes “the common general knowledge” for “the matter cited as forming part of the ‘state of the art’”.
The error is that, at step 3, the inventive concept is not to be compared
to the common general knowledge but to the prior art.
[48] One of the advantages of the Windsurfing/Pozzoli framework is
that it has brought to the fore the distinct conceptual steps in assessing
obviousness. It will be recalled that section 2 of the Act defines an invention
as a something new and useful. Patent law has different ways of addressing “newness” or novelty such as anticipation and double
patenting. Obviousness is not concerned with novelty as a stand-alone ground of
invalidity; on the other hand, if a patent does not contain something new,
there can be no invention. This is why step 3, of the Windsurfing/Pozzoli
framework begins “Identify what, if any, differences…”.
If there are no differences, the inquiry is at an end.
[49] This logic was applied in In re I. G. Farbenindustrie A. G.'s
Patents, (1930), 47 R.P.C. 289 (Ch. D.) (Farbenindustrie) quoted
with approval in Apotex Inc. v. Sanofi-Synthelabo Canada Inc., 2008 SCC
61 at paragraph 9, [2008] 3 S.C.R. 265, a case dealing with selection patents
which, as was noted there, are subject to the same principles as any other
patent. In the course of his analysis, Maugham J. noted that if the compounds
claimed in the selection patent had been made before, the latter would fail “would fail for want of novelty” : Farbenindustrie
at p. 322.
[50] So the exercise at step 3 involves an assessment of whether the
patent in suit has novel elements but this does not answer the question of “Novel relative to what, the common general knowledge or the
prior art?” In principle, novelty should be determined relative to the
prior art since it comprises all of what has been done before. The common
general knowledge is merely a subset of the prior art: see Eli Lilly Canada
Inc. v. Mylan Pharmaceuticals ULC, 2016 FCA 119 at paragraphs 23-25, [2017]
2 F.C.R. 280.
[51] In Anglo-Canadian jurisprudence, the comparison at step 3 is to the
prior art. In Canada, this position is reflected in section 28.3 of the Act.
[52]
Step 3 of the Windsurfing/Pozzoli
framework asks what differences exist between “the
matter cited as forming part of the ‘state of the art’ and the inventive
concept of the claim or the claim as construed.” The expression the
‘state of the art’ is a term of art in English law.
[53] At the time Windsurfing was decided, the Patent Act, 1949,
12, 13 & 14 Geo. 6 Ch. 87, was in force. It dealt with obviousness in
the following terms:
32.-(1) Subject to the provisions of this
Act, a patent may, on the petition of any person interested, be revoked by the
court any of the following grounds, that is to say,-
…
(f) that the invention, so far as
claimed in any claim of the complete specification, is obvious and does not
involve any inventive step having regard to what was known or used,
before the priority date of the claim, in the United Kingdom; (my emphasis)
[54] In Windsurfing, at page 73, Oliver L.J. described step 3
in his framework in the following way:
The third step is to identify what, if any
differences exist between the matter cited as being “known and used” and the
alleged invention.
[55] In the course of his restatement of the framework in Pozzoli,
Lord Jacob reformulated step 3. At paragraph 22 of his reasons Lord
Jacobs says:
The third step also requires a little
reformulation - Windsurfing was a case under the 1949 Act where the
statutory words for the prior art were “known or used”. The European Patent
Convention uses the words “state of the art”.
[56] As a result, the words “state of the art”
in step 3 of the Windsurfing/Pozzoli framework are a reference to
the prior art. In Plavix, the Supreme Court did not specifically comment
on the meaning of “the state of the art”, but in
the course of its discussion of the Lundbeck factors it said the
following:
It is true that obviousness is largely
concerned with how a skilled worker would have acted in the light of the
prior art. … if the inventor and his or her team reached the invention
quickly, easily, directly and relatively inexpensively, in light of the
prior art and common general knowledge, that may be evidence supporting a
finding of obviousness. … Their course of conduct would suggest that a skilled
person, using his/her common general knowledge and the prior art, would
have acted similarly and come up with the same result.
Plavix, at paragraphs 70-71
[57] I conclude from this that the Supreme Court took the same view of
the role of the prior art in the obviousness analysis as the English Courts. It
would be surprising if it were otherwise given the provisions of section 28.3
of the Act which provides as follows:
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28.3The subject-matter defined by a claim in an application for a
patent in Canada must be subject-matter that would not have been obvious on
the claim date to a person skilled in the art or science to which it
pertains, having regard to
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28.3 L’objet que définit la
revendication d’une demande de brevet ne doit pas, à la date de la
revendication, être évident pour une personne versée dans l’art ou la science
dont relève l’objet, eu égard à toute communication :
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(a) information disclosed more than one year before the filing
date by the applicant, or by a person who obtained knowledge, directly or
indirectly, from the applicant in such a manner that the information became
available to the public in Canada or elsewhere; and
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a) qui a été faite, plus d’un an
avant la date de dépôt de la demande, par le demandeur ou un tiers ayant
obtenu de lui l’information à cet égard de façon directe ou autrement, de
manière telle qu’elle est devenue accessible au public au Canada ou ailleurs;
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(b) information disclosed before the claim date by a person not
mentioned in paragraph (a) in such a manner that the information became
available to the public in Canada or elsewhere.
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b) qui a été faite par toute
autre personne avant la date de la revendication de manière telle qu’elle est
devenue accessible au public au Canada ou ailleurs.
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[58] Section 28.3 is essentially to the same effect as the legislation in
effect in the U.K. except that it specifically excludes certain elements of
prior art, that is, those elements disclosed or made known by specified persons
less than 1 year from the material date.
[59] In the end, the jurisprudence and the Act confirm that step 3 requires
a comparison between the inventive step (or the claim as construed) and the
prior art. To the extent that I said otherwise at paragraph 48 of Bristol-Myers
Squibb Canada Co. v. Teva Canada Ltd., 2017 FCA 76, I misspoke. The correct
position is found at paragraphs 44, 65 and 67.
[60] To conclude, a word about “the matter cited
as forming part of the prior art”, the phrase used in Pozzoli and
Plavix. The matter cited as forming part of the prior art is simply the prior
art relied upon by the person alleging obviousness. Obviousness is not
determined by reference to the prior art at large. The person alleging
obviousness must point to one or more elements of prior art which make the
impugned invention obvious. The choice of those elements of prior art is
entirely in the hands of the party alleging obviousness, limited only by
section 28.3 of the Act which sets out the cut-off date for opposable
prior art. In fact, the challenger may rely on a combination of pieces of prior
art under the “mosaic” theory of obviousness: Wenzel
Downhole Tools Ltd. v. National-Oilwell Canada Ltd., 2012 FCA 333 at
paragraph 87, [2014] 2 F.C.R. 459.
[61] The Federal Court’s paraphrase of step 4 of the Windsurfing/Pozzoli
framework also introduces, if not an error, then an oversimplification of the
original statement of that step. At step 4, Lord Jacob inquired if the
differences identified at step 3 constituted steps “which would have been obvious to the person skilled in the
art or do they require any degree of invention?”: Pozzoli, at paragraph
23. The Federal Court’s formulation asks whether those differences require a
degree of invention i.e. inventiveness or whether they are more or less
self-evident. The error or ambiguity arises in the reference to “self-evident”.
[62] As has previously been pointed out, if the difference between the
inventive step (or the claim as construed) and the prior art can be bridged by
the Skilled Person using only the common general knowledge of such a person,
the “invention” is obvious: Bristol-Myers
Squibb Canada Co. v. Teva Canada Ltd., 2017 FCA 76 at paragraph 65,
146 C.P.R. (4th) 216. It is at this point that the common general knowledge is
relevant. The Skilled Person can have recourse to their common general
knowledge supplemented by those pieces of prior art which could be discovered by
a reasonably diligent search: see, for example, Uponor AB v. Heatlink Group
Inc., 2016 FC 320 at paragraph 46, 139 C.P.R. (4th) 393; Hoffmann-La
Roche Ltd. v. Apotex Inc., 2011 FC 875 at paragraph 55, 104
C.P.R. (4th) 233. In my view, this inquiry goes beyond asking whether the
relevant differences are self-evident or not.
[63] I conclude from this that the Federal Court erred in its formulation
of the Windsuring/Pozzoli framework and, as we shall see, it applied
that erroneous formulation to the facts of the case before it.
[64] The reasoning which led the Court to its articulation of the
inventive concept is found in the following paragraph:
Considering the Common General Knowledge, it
is apparent that the invention is the effective rigidifying amount of an
aqueous solution of water soluble polymer that leads to rigidification as
defined by the Court. The Patent is argued to be an advancement over what was
known and part of the Common General Knowledge as to the potential result of a
solution addition of water soluble polymers to a mineral slurry. Thus, the
difference and the inventive concept is that an effective amount of solution
addition of water soluble polymer can result in a rigidification analogous to
the deposit of a paste thickener. It is noted that this type of deposit is only
one of several claimed by the Patent under the disguise of rigidification.
Reasons at paragraph 191.
[65] The Court’s reasons on the issue of the inventive concept are somewhat
elliptical but it appears that it first defined the invention, then referred to
the fact that the invention is an advance over the common general knowledge,
and concluded that the difference between the two is the inventive concept.
[66] This methodology appears to conflate steps 2 and 3 of the Windsurfing/Pozzoli
framework as it was paraphrased by the Federal Court but instead of comparing
the inventive step to the common general knowledge, it compares the invention
to the common general knowledge to arrive at the inventive step.
[67] The final step of the Federal Court’s analysis is ambiguous. Having
previously identified the invention as:
“the effective rigidifying amount of an
aqueous solution of water soluble polymer that leads to rigidification as
defined by the Court” and the inventive concept as:
and the inventive concept as:
“an effective amount of solution addition of
water soluble polymer can result in a rigidification analogous to the deposit
of a paste thickener”,
it asked itself if:
“it was obvious to the Skilled Person that
an effective addition of the polymers listed in the 581 Patent would result in
rigidified deposit.”
Reasons at paragraphs 191-192.
[68] It is not apparent if the Federal Court was asking whether the
invention or the inventive concept was obvious. In either case, from the point
of view of the Windsurfing/Pozzoli framework, the Federal Court was
asking itself the wrong question. The inquiry at step 4 is whether the
difference between the inventive concept (or the claim as construed) and
the prior art can be bridged by the Skilled Person using only their common
general knowledge and other information which they could have found by making a
reasonably diligent search. If it can, then the claimed invention is obvious.
From the point of view of the ultimate issue, the question is, in fact, whether
the invention is obvious but the point of the Windsurfing/Pozzoli
framework is to break that question down into the discrete elements found at
steps 3 and 4.
[69] The Federal Court erred in applying the wrong legal test to the
facts of the case before it which, as taught in Housen v. Nicolaisen, 2002
SCC 33 at paragraph 27, [2002] 2 S.C.R. 235, is an extricable
error of law reviewable on the correctness standard. Rather than return the
matter to the Federal Court to enable it to re-do its analysis, I intend to
undertake that analysis myself.
Application of the correct legal test
[70] The identification of the skill set of the Skilled Person is contentious
only to the extent that Ciba alleges that the Federal Court erred when it “approached the Skilled Person in this case as being
relatively akin to SNF’s expert witness Mr. Hyatt, and the co-inventor of the
581 Patent Mr. Scammell”: Ciba’s Memorandum of Fact and Law at paragraph 33.
I agree with SNF’s response to this argument: “The
Judge was merely observing that the skilled person was ‘much more like Scammell
and Hyatt that a white coat lab technician’, appreciating that in the context
of this practical process, the skilled person had hands-on ‘on the ground’
experience, like Mr. Hyatt and Mr. Scammell”: SNF’s Memorandum of Fact
and Law at paragraph 23.
[71] The identification of the common general knowledge was contentious
with respect to one particular issue, namely whether it included in-line
polymer treatment of tailings. Ciba challenges this finding, but there is
evidence which supports the Federal Court’s decision. Without reviewing the
evidence at length, I note the following excerpt from Dr. Farrow’s report which
the Federal Court quoted in its Reasons:
Flocculation of the particles within the
tailings slurry is achieved in various ways, sometimes by adding flocculant
into the tailings pipe prior to discharge into the tailing pond or dam, or by
adding flocculant into the tailings pond or dam in the vicinity of the
discharge point.
Reasons at paragraph 124.
[72] The next issue is the identification of the inventive concept. We
can find some guidance as to how to approach the inventive concept in Pozzoli.
At paragraph 17 of the Court of Appeal’s reasons, Lord Jacob quoted from
his reasons in the Court of Appeal’s decision in Unilever v. Chefaro,
[1994] R.P.C. 567 (Unilever) at page 580:
It is the inventive concept of the claim in
question which must be considered, not some generalised concept to be derived
from the specification as a whole. Different claims can, and generally will,
have different inventive concepts. The first stage of identification of the
concept is likely to be a question of construction: what does the claim mean?
It might be thought there is no second stage - the concept is what the claim
covers and that is that. But that is too wooden and not what courts, applying Windsurfing
stage one, have done. It is too wooden because if one merely construes the
claim one does not distinguish between portions which matter and portions
which, although limitations on the ambit of the claim, do not. One is trying to
identify the essence of the claim in this exercise.
[73] This passage anticipates the Supreme Court’s teaching on patent
construction in Whirlpool Corp. v. Camco Inc., 2000 SCC 67 at
paragraph 45, [2000] 2 S.C.R. 1067, where it said:
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.
[74] The reminder in Unilever that it is inventive concept of the
claim which is in issue, “not some generalised concept
to be derived from the specification as a whole,” is very apt: Unilever
at page 569. Part of the difficulty in the search for the inventive
concept is the use made, or to be made, of the disclosure portion of the
specification of the patent. In Connor Medsystems Inc v. Angiotech
Pharmaceuticals Inc. [2008] UKHL 49, [2008] R.P.C. 28 (Connor),
Lord Hoffman wrote at paragraph 19 that “[t]he
patentee is entitled to have the question of obviousness determined by
reference to his claim and not to some vague paraphrase based upon the extent
of his disclosure in the description.”
[75] This emphasis on the claims is consistent with section 28.3 of
the Act which stipulates that it is “the subject-matter
defined by a claim” which must not be obvious.
[76] Lord Jacob was alive to the possibility that difficulties in the
identification of the inventive concept could lead to “unnecessary
satellite debate”. His counsel was that “if a
disagreement about the inventive concept of a claim starts getting too
involved, the sensible way to proceed is to forget it and simply to work on the
features of the claim”: Pozzoli at paragraph 19. Lord
Hoffman wrote, once again in Connor at paragraph 20, that the
inventive concept “is a distraction almost as soon as
there is an argument as to what it is.”
[77] There may be cases in which the inventive concept can be grasped
without difficulty but it appears to me that because “inventive
concept” remains undefined, the search for it has brought considerable confusion
into the law of obviousness. That uncertainty can be reduced by simply avoiding
the inventive concept altogether and pursuing the alternate course of
construing the claim. Until such time as the Supreme Court is able to develop a
workable definition of the inventive concept, that appears to me to be a more
useful use of the parties’ and the Federal Court’s time than arguing about a
distraction or engaging in an unnecessary satellite debate.
[78] As a result, I turn to the construction of Claim 1 upon which,
either directly or indirectly, all other claims depend. For ease of reference,
I reproduce Claim 1 below:
A process of
rigidifying a material whilst retaining the fluidity of the material during
transfer, in which the material comprises an aqueous liquid with dispersed
particulate solids that is transferred as a fluid to a deposition area, then
allowed to stand and rigidify, by combining with the material during transfer
an effective rigidifying amount of an aqueous solution of a water-soluble
polymer, said water-soluble polymer having an intrinsic viscosity of at least 5 dl/g
(measured in 1 M NaCl at 25 °C).
‘581 patent at page 40.
[79] The remaining 49 claims of the patent add various qualifications to
this basic outline, specifying, for example, the characteristics of the
dispersed particulate solids, the characteristics of the water-soluble polymer,
and the source of the original aqueous liquid.
[80] The Federal Court’s construction of Claim 1 is largely focussed
the words “rigidify” and “rigidification”. The Court noted that “rigidify” and “rigidification”
were coined words which were neither scientific nor technical terms. In the
end, the Federal Court held that “rigidification”
meant “increasing the yield stress of a mineral deposit
rapidly whereby the flow of the deposit is minimized and the weight of
subsequent layers of like deposits is supported”: Reasons at paragraph 163.
[81] The Court’s references to minimizing the flow of the deposit and to
supporting subsequent layers of like deposits are both taken from page 15
of the patent which teaches that the rheological (flow) characteristics of the
treated slurry or tailings are important because once those materials are
allowed to stand, flow must be minimized and solidification of the material
must proceed rapidly so that they can withstand the weight of subsequent layers
of treated material.
[82] Minimizing flow must not be confused with the requirement that treated
materials must be capable of being transferred without solids settling out
during transfer. The flow referred to in the Court’s construction of
rigidification is the flow of material once it is discharged at the deposition
site and not its fluidity in the course of transfer to that area.
[83] Claim 1 describes a process for rigidifying a material which
comprises an aqueous liquid with dispersed particulate solids - a slurry - by
adding an effective amount of an aqueous solution of a water-soluble polymer to
the material while it is being transferred as a fluid i.e. in-line addition. At
the deposition area, the material is allowed to stand and rigidify, which means
that the flow of the deposit is minimized and the weight of subsequent layers
of like deposits is supported. The polymer solution must have an intrinsic
viscosity of at least 5 dl/g (measured at 1 M Na Cl at 25° C).
[84] The expression “effective rigidifying
amount” is ambiguous, which allows reference to the disclosure to
understand what is meant. In the course of a discussion as to the problems
associated with the treatment of tailings slurry, the patent refers to the fact
that attempts have been made to solve those problems “by
treating the feed to the tailings dam using a coagulant or a flocculant”
but that these attempts were unsuccessful “as these
treatments have been applied at conventional doses […]”: ‘581 patent at
page 3, lines 21-25. The disclosure portion of the patent identifies preferred
ranges of doses of flocculant which it claims have a beneficial effect.
[85] The conclusion to be drawn from this is that while conventional
doses of flocculant were ineffective in solving the problems to which the
invention was directed, doses in the ranges described in the patent, which must
be taken to be outside the range of conventional doses, would have a beneficial
effect.
[86] Having thus construed claim 1 of the ‘581 patent, the next step
is to identify the differences between the claim as construed and the prior art
relied upon by SNF. The Federal Court noted in its Reasons that SNF relied on
two patents or a combination of the two. In fact, the Federal Court’s analysis
focussed on the Gallagher patent. SNF’s reliance on the Gallagher patent in not
surprising since both it and the ‘581 patent address the same problem using the
same class of compounds and both are owned by Ciba. In fact, the Federal Court
was of the view that the ‘581 patent was drafted with the Gallagher patent in
mind: see the Court’s discussion of the evidence of Mr. William Peatfield,
the patent agent who drafted the ‘581 patent at paragraphs 40-49 of the Reasons.
[87] The teachings of the Gallagher patent are described as follows in
the ‘581 patent:
WO-A-0192167 [the Gallagher patent] describes
a process where a material comprising a suspension of particulate solids is
pumped as a fluid and then allowed to stand and rigidify. The rigidification is
achieved by introducing into the suspension particles of a water soluble
polymer which has an intrinsic viscosity of at least 3 dl/g. This treatment
enables the material to retain its fluidity was [sic] being pumped, but upon
standing causes the material to rigidify. This process has the benefit that the
concentrated solids can be easily stacked, which minimises the area of land
required for disposal. … The importance of using particles of water soluble
polymer is emphasised and it is stated that the use of aqueous solutions of the
dissolved polymer would be ineffective.
‘581 patent at page 5,
lines 31-32, page 6, lines 1-11.
[88] For ease of reference, I set out Claim 1 of the Gallagher
patent:
A process in which material comprising an
aqueous liquid with dispersed particulate solids is pumped as a fluid then
allowed to stand and rigidify and the rigidification is improved whilst
retaining the pumpability of the material by combining polymeric particles with
the material during or prior to pumping the material, wherein the polymeric
particles comprise water-soluble synthetic polymer which has an intrinsic
viscosity of at least 3 dl/g…
Gallagher patent at page 23, lines
2-10.
[89] As can be seen, much of what is claimed in Claim 1 of the ‘581
patent is found in the Gallagher patent. In particular, the Gallagher patent
teaches the treatment of a solution of dispersed particulate matter by the
in-line addition of water-soluble polymer. The treated solution maintains its
fluidity while being pumped but solidifies or rigidifies upon deposition.
[90] Both the Gallagher patent and the ‘581 patent refer to a lower
threshold for intrinsic viscosity. In the case of the Gallagher patent, the
threshold is 3 dl/g while in the ‘581 patent it is 5 dl/g. However in
both cases, the disclosure portion of the specification indicates a preferred
range of intrinsic viscosity. In the case of the ‘581 patent, the preferred
range is 8-25 dl/g while the more preferred range is 11 or 12 dl/g to 18
or 20 dl/g. The Gallagher patent refers to a preferred range of 8-20 dl/g
and a more preferred range of 11 or 12 to 16 or 17 dl/g. I have not been
able to find any evidence which would show that there is some significance to
the difference between the ranges.
[91] The elements of the ‘581 patent which are not found in the Gallagher
patent are the notions of an “effective rigidifying
amount” and of “an aqueous solution of a water
soluble polymer.”
[92] The next step in the analysis, step 4, is to determine if these
differences could be bridged by the skilled person using only their common
general knowledge and those elements of the prior art which that person could
find by conducting a reasonably diligent search. Simply put, would the Skilled
Person with the Gallagher patent in hand, using only the information identified
above, arrive without difficulty at the conclusion that slurries could be
treated to produce the desired effect by using “an
effective rigidifying amount” of “an aqueous
solution of a water-soluble polymer”?
[93] It will be recalled that the Federal Court found that the common
general knowledge included the knowledge that slurries could be treated using
an aqueous solution of water-soluble polymers: see Reasons at paragraph 186.
That finding of fact means that, on this point of difference, the Skilled
Person would readily bridge the difference between claim 1 as construed
and the prior art (as exemplified by the Gallagher patent) because the
knowledge required to do so was part of the common general knowledge. That
aspect of claim 1 was therefore obvious.
[94] This leaves the question of the use of an effective rigidifying
amount of such an aqueous solution of water-soluble polymers. On that issue, the
Federal Court reasoned as follows:
The Skilled Person would have gone directly
and without difficulty to the step of using a minimum dosage of polymer to
achieve the level of rigidification of the slurry deposit for the job. It is
routine for the Skilled Person to decide, inter alia: the nature of the
polymer; its form and dosage; and the point of addition to the slurry line.
Thus, applying an “effective” amount is obvious, as the Skilled Person would
continue to apply the necessary polymer to achieve the necessary outcome and
discontinue application once overdosing occurred.
Reasons at paragraph 195.
[95] I agree with this reasoning. A Skilled Person, using their common
general knowledge, would be able to bridge the difference between the claim as
construed and the cited prior art (the Gallagher patent). The Federal Court
found that the common general knowledge included the knowledge that
flocculation was dose-dependent: Reasons at paragraph 185. It requires no
inventiveness to go from that knowledge to the knowledge that increasing the
dose beyond conventional dosage would eventually produce the desired results.
As a result, the invention claimed in the ‘581 patent is obvious.
[96] Even though this conclusion was sufficient to dispose of the issue
of obviousness, the Federal Court then embarked on the “obvious
to try” analysis which the Supreme Court endorsed in Plavix. In
my view, the Federal Court need not have done so. The finding that the skilled
person would have known to use an aqueous solution of water-soluble solution
and then to adjust the dose until the desired result was achieved means that
the question of “obvious to try” either did not
arise or had already been answered. To the extent that Ciba argues that the
Federal Court erred in embarking upon the “obvious to
try” analysis, it is correct though not for the reasons it suggests.
[97] The result is that Claim 1 is obvious and, since all other
claims are directly or indirectly dependent on Claim 1, the ‘581 patent is
invalid.
CONCLUSION
[98] I would therefore dismiss the appeal with costs.
"J.D. Denis Pelletier"
“I agree
Donald J. Rennie J.A.”
WOODS J.A. (Concurring reasons)
[99] I have read the well-written reasons of the majority by Justice
Pelletier and agree with my colleagues that this appeal should be dismissed. I
also concur with the reasons, except that I would decline to provide an opinion
on the issue discussed at paragraphs 51 to 63, above. This part of the analysis
concerns the effect of section 28.3 of the Act on the determination of
obviousness.
[100] In my view, it is preferable for this issue to be left for another
day, as it was in E. Mishan & Sons, Inc. v. Supertek Canada Inc., 2015
FCA 163, 134 C.P.R. (4th) 207 at paragraph 21. The issue is better
addressed in an appeal where it is relevant to the outcome and in which the Court
has the benefit of full submissions from counsel, which was not the case here.
"Judith M. Woods"
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