SNF (Australia) Pty Ltd v Ciba Specialty Chemicals Water Treatments Limited [2012] FCAFC 95 | Case summary

SNF (Australia) Pty Ltd v Ciba Specialty Chemicals Water Treatments Limited [2012] FCAFC 95 | Case summary | Zoe

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THE CONTEXT 4 The case concerns the processes by which tailings from mining operations are separated and stored. Commonly, tailings are transported as slurry to tailing dams where the slurry is allowed to settle out or sediment. At first instance the terms "settle" and "sediment" and cognate terms were sometimes used as alternatives ("settlement or sedimentation"), sometimes cumulatively, "settlement and sedimentation" and sometimes, in effect, synonymously. The Oxford English Dictionary (2nd ed) (the "OED") relevantly defines the term "settle" as: Of a liquid: To become still after agitation or fermentation, so that the suspended particles or impurities are separated as scum or sediment … . 5 A second meaning is: Of suspended particles or impurities in a liquid: To come to rest after agitation or disturbance; to collect as scum or sediment by gravitation … . 6 The word "settlement" relevantly means: The act of settling and clarifying after agitation or fermentation … . The sinking of floc and other solid particles in liquid sewage … . 7 The word "sediment" as a noun means: A settling, sinking down … . Matter composed of particles which fall by gravitation to the bottom of a liquid … . 8 As a verb, the word means: To deposit as sediment … . Of a liquid: to deposit a sediment. 9 Other parts of the definition identify the word as the process by which rocks may be formed. The word "sedimentation" means: Deposition of sediment … . 10 It seems that in some senses the words "settlement" and "sedimentation" may be synonymous. However it also seems that sediment may be one of two forms of solid which may emerge from a settlement process, the other being scum. Hence the word "settlement" may have a broader meaning than does the word "sedimentation". I shall generally use the term "settlement and sedimentation" as including both the settling process and the accumulation of solids on the dam floor. 11 In the tailings dam the solids settle on the floor of the dam and accumulate. The water from the slurry is reused in the mining operation. Tailings consist of particles of different sizes. In the course of settlement and sedimentation larger particles may settle more quickly than smaller particles, thus causing the larger and smaller particles to accumulate in separate piles. Such piles will be structurally unstable. There is, however, evidence that as these piles consolidate over time, they may strengthen and become more stable. This proposition is, to some extent, controversial. The smaller particles may also contaminate the water being drawn off for reuse. The claimed invention is said to cause rapid "rigidification" of solids. Such rapid rigidification causes the smaller and larger particles of solids to accumulate in more homogenous heaps (or stacks), with a quicker release of water. The first and second respondents (collectively "Ciba") allege infringement of the Patents by the appellant ("SNF"). SNF concedes that if the Patents are valid, its process (the "SNF process") infringes.

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THE CONSTRUCTION POINT AT TRIAL 12 At first instance construction of the words "rigidify" and "rigidification", as used in the Patents, assumed some importance. At [45] the primary Judge said that such construction was "significant for assessing whether the prior art … acts teach rigidification as opposed to settling or sedimentation", and that the question "also has implications for the clarity and sufficiency grounds …". At trial, SNF submitted that the words "rigidify" and "rigidification" have their ordinary dictionary meanings, and that such meanings are wide enough to include consolidation of sedimented solids. The use of the words to describe a process leading to the formation of rocks might support that view. However that argument was not put below or on appeal. Ciba submitted that the words, as used in the Patents, do not describe the effect produced by consolidation of solids following settlement and sedimentation. Ciba submitted that: the outcome of rigidification will be a process producing a different tailings deposit, with different characteristics, different dewatering potential in a quite different period of time to natural settlement and sedimentation processes. 13 These different characteristics are said to be attributable to the formation of a "networked structure" throughout the rigidified material. The evidence and Ciba's submissions suggest that such networking involves chemical bonding. I proceed on that basis. 14 At [47] the primary Judge said: Further, the evidence establishes that "rigidification" is not a term of art. One may accept that, in ordinary usage, "rigidify" means "[t]o become rigid, set, or inflexible"; and "rigid" means, in relation to material, "stiff; not pliant or flexible; firm; hard". See the [OED]. The question is what does the word "rigidification" signify in the specification and claims of Patent 944? 15 As I understand it, her Honour treated resolution of the construction question as substantially dependent upon her resolution of the conflict between the evidence of Professor Slatter (called by SNF) and that of Dr Farrow (called by Ciba), although her Honour also relied upon evidence concerning this aspect of the case from other witnesses called by SNF. At [48] her Honour observed: … [SNF] argued that the term "rigidification" and its variants within Patent 944 did not differ from the processes of settling and sedimentation disclosed in the prior art documents and acts. On the other hand, the Ciba respondents contended that rigidification was relevantly different from settling and sedimentation. The experts also differed on this point. Professor Slatter's view was that the process of settling, sedimentation and rigidification were not relevantly different because settling and sedimentation would always lead to rigidification as claimed. Dr Farrow disagreed, for the reasons explored below.

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The evidence - Dr Farrow 20 Her Honour understood Ciba to submit that Professor Slatter's view that the processes of settling and sedimentation would lead to rigidification as claimed "was not borne out by the evidence". This submission was largely based upon Dr Farrow's evidence that "(i)n the context of Patent 944, 'rigidification' was a qualitative term involving a 'networked structure' ". At [62]-[64] her Honour said: 62 Dr Farrow said that, in his view, in the context of Patent 944, "rigidification" was a qualitative term, although one that Patent 944 explained clearly as "a networked structure". Reading Patent 944, Dr Farrow said that: [T]he outcome of rigidification will be a process producing a different tailings deposit, with different characteristics, different dewatering potential in a quite different period of time to natural settling and sedimentation processes. Dr Farrow deposed (in his first affidavit) that the rigidified tailings material would: (a) be less likely to spread laterally after deposition, enabling more efficient land use; (b) more rapidly form a solid structure in the form of a beach or stack; (c) have a greater yield stress when deposited; (d) have increased uniformity or homogeneity of fine and coarse particles; (e) by reason of its heaped geometry, result in downward compression forces driving water out of the stack; and (f) result in more rapid and improved clarity of water release. 63 As to settling and sedimentation, Dr Farrow acknowledged that: … flocculation and settling in an environment with a fixed base (eg cylinder or a walled tailings dam or pond) will lead to the formation of a denser (consolidated) sediment due to the compactions force exerted as material accumulates on top of previously settled material. This sediment will often have a higher yield stress than the original feed suspension (eg thickener underflow) which will slowly increase with time. The extent of densification will increase as the sediment height increases (i.e. the compaction force), but only up to a point. 64 Dr Farrow disagreed, however, with Professor Slatter's proposition that, when the individual aggregates or floccs settled on the bottom of a tailings dam, there would be a mechanism by which they were linked and the result would be a structure the same as that formed by "beaching". Dr Farrow explained how sediment formed by flocculation, settling and consolidation would have a yield stress, which was "due to entanglement of individual aggregates" rather than "due to networking of the entire solid mass". Dr Farrow said that: In contrast, the '944 process commences with networking of the solids within the tailings stream, this is a process termed rigidification with '944. This is, in my opinion, an entirely different process to that of settling and consolidation. The 944 process requires a sufficiently high initial concentration (as often is achieved in a thickener underflow) so that there is the prospect of being about to create a network structure through the addition of flocculant. Hence the initial solids concentration is a key factor in the '944 process (as indicated on page 8, line 29 of '944). The solids need to be sufficiently concentrated so that when a flocculant is added the flocculant will be able to bridge all the particles together to form a network, not just form a multitude of individual aggregates. Consequently the solids concentration needs to be near the point where most solids are fairly close to touching, but it is not necessary for the initial solids concentration to be such that all solids are in contact. Flocculants work because they are very high molecular weight molecules, for example 20 million Daltons. However, they are still soluble and when in solution have a significant molecular size e.g. 1 micron. This enables flocculant molecules to form networks from particles that are not already touching. This process is not one where the particles remain stationary and the flocculant then bridges them together, rather it is a dynamic process where small "sub-networks" will initially form and then in the presence of the remaining flocculant these smaller "sub-networks" will progressively join to form an overall network (which is the aim of '944). In doing so, particles will be drawn together and significant volumes of water will become particle free and ready to drain away once the network solids are allowed to stand (as is the case on the free drainage region of a Belt Press Filter). 21 Dr Farrow's evidence concerning the characteristics of rigidified tailings appears in paras 33 and 34 of his affidavit filed on 24 July 2009. These characteristics are generally expressed in comparative terms, eg "less likely", "more efficient", "more rapidly, "greater yield stress", etc. Dr Farrow did not, at that point, identify a comparator. However, in para 35 he stated: Rigidification can be contrasted to a process of flocculation leading to sedimentation where the tailings material delivered to a deposition or impoundment facility has a low rheology or yield stress (ie, it is not rigidified) which results in the coarse fractions of the deposited materials settling to the bottom of the impoundment area with lateral segregation of the fine fractions and limited clear supernatant forming above the deposited or sedimented material. In the process of sedimentation, the deposited fine material has a greater tendency to flow laterally and the fine and coarse particles have a tendency to separate or segregate. Again I make reference to the diagrams which appear at pages 166 to 167 of JBF-1. 22 Hence it seems that the various comparisons are with a process of settlement and sedimentation, suggesting that the solids produced by such a process possess the compared characteristics, but to a lesser degree than is achieved using the claimed invention. Concerning settlement and sedimentation processes, Dr Farrow said, in his Notes of Supplementary Evidence: In his oral evidence, Professor Slatter at T 408:41-2 said, in relation to the structure of individual aggregates (also called flocs) settled on the bottom of a tailings dam that "I believe that once they touch each other there will be some mechanism by which they are linked". I do not agree that this will lead to the formation of a structure that is the same as that formed by "beaching" as that term was used by Professor Slatter and as shown in the video. It is true that flocculation and settling in an environment with a fixed base (eg a cylinder or a walled tailings dam or pond) will lead to the formation of a denser (consolidated) sediment due to the compactions force exerted as material accumulates on top of previously settled material. This sediment will often have a higher yield stress than the original feed suspension (eg thickener underflow) which will slowly increase with time. The extent of densification will increase as the sediment height increases (i.e. the compaction force), but only up to a point. The long-term characteristics of sediment formed by settling then consolidation will be very different to the characteristics of the same feed material that has been "beached". A sediment formed by settling/consolidation will comprise flocs that initially settled, then stop as they reached the top of the sediment bed. At this point they will not have undergone any dewatering during the settling process. As the settled aggregates are covered by more settled aggregates they will start to experience a force due to the weight of the overlying material. This will induce only limited densification of the aggregates. … 23 Thus it seems that Dr Farrow agreed that sedimentation will lead to increased yield stress. This is consistent with Professor Slatter's definition of the term "rigidification". However Dr Farrow asserted that rigidification necessarily also involves the networking effect.

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Some problems with Dr Farrow's evidence 24 At this point it is worth observing that Ciba's submissions tend to confuse process and outcome. In my view the Patents describe a process which if followed, is said to produce an outcome, namely improved rigidity of solids. The process of improving rigidity is a process of rigidification. A process of settlement and sedimentation will, according to Professor Slatter, produce heaps of solids which will consolidate and rigidify. Dr Farrow accepted that some rigidification will occur as sediment consolidates. Instinctively, one would say that such a process is a process of rigidification. However Dr Farrow said that rigidification, by definition, involves chemical bonding, and that sediment is not bonded. The concept of networking or chemical bonding is not mentioned in the Patents. 25 Ciba's case seems to be that various physical characteristics, such as "stacking" of solids and the rapid release of water are evidence of such networking. "Stacking" is said to be an event which may occur if the solids rigidify quickly after they leave the conduit and enter the tailings dam. Ciba submits that such characteristics distinguish processes of settlement and sedimentation from the process of rigidification. However stacking is specifically claimed in claim 3, not in claim 1. Similarly, the production and quality of water are claimed in claim 5, but not in claim 1. The structure of the claims suggests that neither stacking nor the production of water, nor the production of better quality water is a necessary feature of rigidification as that term is used in claim 1 and, presumably, elsewhere in the claims and in the body of the specification. If so, then it cannot be a basis for excluding processes of settlement and sedimentation from being processes of rigidification. Further, as will be seen, the Patents seem to attribute the characteristics of stacking and water production to processes involving settlement and sedimentation. See Patent 944 at p 1 l 29 to p 2 l 19. Counsel for Ciba asserts as much in the written outline of submissions at paras 15 and 41. 26 I note that much of the evidence concerning the alleged characteristics of the claimed invention consists of observations made by the witnesses Bembrick and Schroeter of the SNF process. Apparently Ciba submits that as that process admittedly infringes (if the Patents are valid) it provides evidence which may assist in construing the claims. I find this proposition difficult to accept.

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THE PRIMARY JUDGE'S CONCLUSIONS CONCERNING RIGIDIFICATION 27 Her Honour's conclusions as to the meaning of the term "rigidification" appear at [69]-[75] as follows. 69 I accept that, as Professor Slatter said, rigidification is a process of developing strength (in terms of yield stress). For the reasons already stated, I also accept that, as Dr Farrow said, rigidification is a qualitative term, in which a networked structure is formed. As explained, to the extent that Dr Farrow's evidence is inconsistent with Professor Slatter's on this issue of rigidification, I accept the evidence of Dr Farrow. 70 The meaning that Dr Farrow accorded the word "rigidification" accorded with the natural meaning of the word, considered in the context of the specification as a whole. The meaning for which SNF contended involved focussing on individual words and phrases, without having regard to what was evidently being taught, with the result that what was being disclosed was obscured. 71 Dr Farrow's evidence supported the Ciba respondents' basic contention that, reading the specification as a whole, when compared with the process of settling and sedimentation, the claimed "process of improving rigidification": (a) results in fast solidification (in that material has greater yield stress); (b) produces more recovered water; and (c) results in chemically-bonded tailings that occupy a smaller surface area, which is more quickly rehabilitated. SNF maintained that concepts of speed or time were not essential to claim 1. I reject this proposition because speed or time are inherent in the "process of improved rigidification", of which claim 1 speaks: see, for example, Patent 944 at pp 13-14. 72 If "rigidification" is understood in this way, then I accept that, reading the specification as a whole, the specification gives meaning and content to a process of improving rigidification of a material the subject of the claims. The process as taught does not encompass settling and sedimentation. 73 By way of further explanation, I make the following further brief comments about the evidence given by the experts. Professor Slatter is undeniably expert in his field of rheology. As already noted, however, his evidence at trial was in large part at a theoretical level, and he had not been afforded an opportunity to study Mr Bembrick's video and paper. Further, there were, as noted already, deficiencies in Professor Slatter's evidence, some of which was not borne out by the evidence given by other witnesses such as Mr Bembrick and Mr Schroeter (both of whom were impressive witnesses). 74 More generally, the Ciba respondents criticised Professor Slatter's approach here and elsewhere as overly technical. They complained that Professor Slatter considered the specification "as if it was a laboratory protocol in which every term should be defined with enormous technical precision". Generally speaking, Professor Slatter's approach was precise and, at times, exacting - an approach in keeping with his professional training and status - but not directly transferable to the method of patent construction to be adopted by a court. Further, with respect to this and other issues, Dr Farrow's expertise in chemistry proved to be more helpful that [sic] Professor Slatter's expertise in rheology (though the expertise of both was relevant to understanding the claimed process and the prior art). 75 Given the practical nature of what is taught by the specification, Dr Farrow's background as an experienced member of the CSIRO placed him in a better position than Professor Slatter to identify and explain this teaching. The effect of Dr Farrow's evidence was to assist in understanding the chemistry and practical effect of the process as taught in the specification and as claimed. Dr Farrow's evidence focussed attention on the teaching of the specification as a whole and, when viewed in this way, the teaching in the specification made clear what was meant by a "process of improving rigidification" in integer (a) of claim 1, as well as by such words as "stand and rigidify" in integer (b) and "effective rigidifying amount" in integer (d). If, however, there had been any doubt about "rigidification" in claim 1, then, as the Ciba respondents noted, it would have been removed by claim 3, integers (l) and (m). 28 At [69] the primary Judge concluded that the term "rigidification" necessarily involves production of the "networked structure" referred to by Dr Farrow in his evidence. I accept that Dr Farrow said as much. I also accept that the SNF process produces that result. I am willing to assume for present purposes that the claimed invention will also do so. 29 Concerning the phrase, "a process of improving rigidification", her Honour said at [46]: … "Improve" in this context, is to make "rigidification" greater in amount or degree; even "to increase the value or excellence" of "rigidification" as applied to the disposition of mineral waste. Compare The Oxford English Dictionary (2nd ed, 1989). Reading the specification as a whole, the word "improve" necessitates a comparison - here with processes other than the claimed process. As the Ciba respondents noted, neither the claims nor the specification assert that "rigidification" of tailings is the "invented" process. 30 At [45] her Honour said that the meaning of the term "rigidification" and its variants are: … significant for assessing whether the prior art documents referred to below at Slatter 10, 12 and 13 and various prior art acts teach rigidification as opposed to settling or sedimentation. … 31 This approach seems to assume a dichotomy between rigidification on the one hand and settling and sedimentation on the other. Neither the claims nor the specification expressly draw, or draws such a distinction.

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PRINCIPLES OF CONSTRUCTION 32 At [21]-[24] the primary Judge identified principles applicable to construction of a patent. In particular, her Honour identified the primary requirement that the specification be read as a whole and "in light of common knowledge in the art before the priority date". Her Honour identified the notional addressee of the specification as the non-inventive person skilled in the art, before the priority date. At [24] the primary Judge recognized that an expert might give evidence as to the meaning which a person, skilled in the art, would give to a technical or scientific term, and as to any special meaning which an ordinary word might convey to such a person. Her Honour also observed that a person having the knowledge, skill and experience of the notional addressee might give evidence as to how he or she would have read the patent but that, ultimately, it was for the Court to construe the patent. 33 In addition to these general propositions I add a number of further limitations, really consequences of the requirements identified by the primary Judge. First, in construing a claim, it is not appropriate to refer to prior art, save to the extent that it is referred to in the specification or comprises part of the common general knowledge of the skilled addressee. See Sartas No 1 Pty Ltd v Koukourou & Partners Pty Ltd (1994) 30 IPR 479 per Gummow J at 485-6. Further, it is not legitimate to construe the claim with reference to the alleged infringement. See CCom Pty Ltd v Jiejung Pty Ltd (1994) 51 FCR 260 at 267-8 and Sartas (supra) at 486. An expert's understanding of how the claimed invention works is also excluded, save to the extent that it would have been so understood by the skilled addressee from a reading of the specification and in light of common general knowledge at the relevant time. 34 In summary, I set out the words of Lord Hoffmann in Kirin-Amgen Inc and Others v Hoechst Marion Roussel Ltd (2004) 64 IPR 444 at [32]-[35]: 32 Construction, whether of a patent or any other document, is of course not directly concerned with what the author meant to say. There is no window into the mind of the patentee or the author of any other document. Construction is objective in the sense that it is concerned with what a reasonable person to whom the utterance was addressed would have understood the author to be using the words to mean. Notice, however, that it is not, as is sometimes said, "the meaning of the words the author used", but rather what the notional addressee would have understood the author to mean by using those words. The meaning of words is a matter of convention, governed by rules, which can be found in dictionaries and grammars. What the author would have been understood to mean by using those words is not simply a matter of rules. It is highly sensitive to the context of and background to the particular utterance. It depends not only upon the words the author has chosen but also upon the identity of the audience he is taken to have been addressing and the knowledge and assumptions which one attributes to that audience. … . 33 In the case of a patent specification, the notional addressee is the person skilled in the art. He (or, I say once and for all, she) comes to a reading of the specification with common general knowledge of the art. And he reads the specification on the assumption that its purpose is both to describe and to demarcate an invention - a practical idea which the patentee has had for a new product or process - and not to be a textbook in mathematics or chemistry or a shopping list of chemicals or hardware. It is this insight which lies at the heart of "purposive construction". If Lord Diplock did not invent the expression, he certainly gave it wide currency in the law. But there is, I think, a tendency to regard it as a vague description of some kind of divination which mysteriously penetrates beneath the language of the specification. Lord Diplock was in my opinion being much more specific and his intention was to point out that a person may be taken to mean something different when he uses words for one purpose from what he would be taken to mean if he was using them for another. The example in the Catnic case was the difference between what a person would reasonably be taken to mean by using the word "vertical" in a mathematical theorem and by using it in a claimed definition of a lintel for use in the building trade. The only point on which I would question the otherwise admirable summary of the law on infringement in the judgment of Jacob LJ in Rockwater Ltd v Technip France SA … is when he says in subpara (e) that to be "fair to the patentee" one must use "the widest purpose consistent with his teaching". This, as it seems to me, is to confuse the purpose of the utterance with what it would be understood to mean. The purpose of a patent specification, as I have said, is no more nor less than to communicate the idea of an invention. An appreciation of that purpose is part of the material which one uses to ascertain the meaning. But purpose and meaning are different. If, when speaking of the widest purpose, Jacob LJ meant the widest meaning, I would respectfully disagree. There is no presumption about the width of the claims. A patent may, for one reason or another, claim less than it teaches or enables. 34 "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. On the other hand, it must be recognised that the patentee is trying to describe something which, at any rate in his opinion, is new; which has not existed before and of which there may be no generally accepted definition. There will be occasions upon which it will be obvious to the skilled man that the patentee must in some respect have departed from conventional use of language or included in his description of the invention some element which he did not mean to be essential. But one would not expect that to happen very often. 35 One of the reasons why it will be unusual for the notional skilled man to conclude, after construing the claim purposively in the context of the specification and drawings, that the patentee must nevertheless have meant something different from what he appears to have meant, is that there are necessarily gaps in our knowledge of the background which led him to express himself in that particular way. The courts of the UK, the Netherlands and Germany certainly discourage, if they do not actually prohibit, use of the patent office file in aid of construction. There are good reasons: the meaning of the patent should not change according to whether or not the person skilled in the art has access to the file and in any case life is too short for the limited assistance which it can provide. It is however frequently impossible to know without access, not merely to the file but to the private thoughts of the patentee and his advisors as well, what the reason was for some apparently inexplicable limitation in the extent of the monopoly claimed. One possible explanation is that it does not represent what the patentee really meant to say. But another is that he did mean it, for reasons of his own; such as wanting to avoid arguments with the examiners over enablement or prior art and have his patent granted as soon as possible. This feature of the practical life of a patent agent reduces the scope for a conclusion that the patentee could not have meant what the words appear to be saying. It has been suggested that in the absence of any explanation for a restriction in the extent of protection claimed, it should be presumed that there was some good reason between the patentee and the patent office. I do not think that it is sensible to have presumptions about what people must be taken to have meant but a conclusion that they have departed from conventional usage obviously needs some rational basis.

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INTEGERS OF THE CLAIM 35 Her Honour accepted Dr Farrow's identification of the integers of the claims in Patent 944 as follows: Claim 1 (a) a process of improving rigidification of a material whilst retaining the fluidity of the material during transfer (b) 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 (c) by combining with the material during transfer (d) an effective rigidifying amount of (e) an aqueous solution of a water-soluble polymer having an intrinsic viscosity of at least 5 dl/g (measured in 1M NaCl at 25º C) (f) in which the material comprises coal tailings. Claim 2 (g) a process according to claim 1 in which the water-soluble polymer is anionic (h) in which the polymer is formed from monomer(s) selected from the group consisting of (meth) acrylic acid, allyl sulphonic and 2-acrylamido-2-methyl propane sulphonic as the free acid or salts thereof (j) wherein the effective rigidifying amount of the water-soluble polymer is in the order of 10 to 3000 grams per tonne of material solids. Claim 3 (k) a process according to claim 1 or claim 2 in which the material is pumped to an outlet (l) where it is allowed to flow over the surface of previously rigidified material and (m) wherein the material is allowed to stand and rigidify to form a stack. Claim 4 (n) A process according to any one of claims 1 to 3 in which aqueous suspensions of fine and coarse particulate materials are combined for the purpose of co-disposal and (o) wherein the effective rigidifying amount of the water-soluble polymer solution is added during or after the mixing of the different waste streams into a homogenous slurry. Claim 5 (p) A process according to any one of claims 1 to 4 in which the material is dewatered during rigidification, releasing liquor and (q) in which the clarity of the liquor is improved by the addition of an aqueous solution of water-soluble polymer. 36 Her Honour also said: Dr Farrow maintained, and for present purposes I accept, that there was an inessential integer in claim 2: namely, "(i) optionally in combination with non-ionic comonomers, selected from the group consisting of (meth) acrylamide, hydroxyl alkyl esters of (meth) acrylic acid and N-vinyl pyrrolidone".

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THE SKILLED ADDRESSEE 37 At [42]-[44] the primary Judge identified the skilled addressee as follows: 43 As counsel for the Ciba respondents submitted in closing, the relevant art is "the art of dealing with tailings in mines". In this case, the skilled addressee is a practical person working in the mining industry, with practical knowledge of and experience in the treatment and disposal of mining wastes. Such skilled addressees would include SNF's technical sales representatives who gave evidence at trial. The gist of their evidence in this regard was that in the course of their ordinary employment they gave technical advice to SNF's customers with respect to processes for treating mining waste. Other skilled addressees might be mines engineers familiar with waste disposal processes (including the plant and equipment used in such processes). 44 Having regard to the evidence adduced at trial, a skilled addressee would have a good working knowledge of: (1) polymers and their use in flocculating mine wastes; and (2) the flow of flocculated and unflocculated mine wastes. A skilled addressee would be able to perform and interpret the routine tests necessary to give effect to a secondary flocculation process. A skilled addressee would not need to be a scientific expert in rheology or chemistry (or polymers). 38 In the last sentence at [44] her Honour was referring to the areas of expertise of Professor Slatter and Dr Farrow respectively, implying that each had expertise well beyond that of the skilled addressee. At [56] her Honour recognized Mr Schroeter, SNF's managing director, as a skilled addressee. At [185]-[186], in considering the associated question of common general knowledge before the priority date, the primary Judge made reference to the evidence of numerous "industry witnesses", making no mention of Professor Slatter or Dr Farrow. However, at [49], her Honour seems to have accepted that the evidence of both men was relevant to the construction issue, particularly as to the "scientific and industrial context in which the claimed process would operate and in which "rigidification" was to be understood". Of course such evidence would necessarily be limited to the knowledge and understanding of the skilled addressee. A possible exception to that general proposition is identified by Lord Reid in Van der Lely NV v Bamfords Ltd [1963] RPC 61 at 72. His Lordship there suggested that the skilled addressee might consult a scientist about the meaning of a technical term. However that exception would not permit consultation about how a word should be understood in the context of the patent as a whole. 39 Both Professor Slatter and Dr Farrow seem to have given evidence concerning the knowledge of the skilled addressee in connection with the issue of sufficiency. See the reasons for judgment at [244] and [247]. As I have previously mentioned, various witnesses gave evidence as to common general knowledge.

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APPEAL CONCERNING THE CONSTRUCTION QUESTION 40 SNF's grounds of appeal on this construction question are effectively that: in adopting Dr Farrow's approach to the meaning of the word "rigidification", the primary Judge erroneously adopted an approach which was inconsistent with the specification in that such approach: required networking as an element of rigidification; and excluded the process of settlement and sedimentation; and the primary Judge erred in adopting Dr Farrow's approach in that his evidence was neither that of a skilled addressee nor evidence as to how a skilled addressee would construe that term. 41 SNF submits that, in construing the Patent, it was essential that the primary Judge distinguish between evidence as to the knowledge of the skilled addressee and other expert evidence. It asserts that her Honour failed so to do and, as a result, incorrectly concluded that the word "rigidification", as used in Patent 944, necessarily describes a process which produces networked solids, and so does not include a process of settlement and sedimentation (which produces strengthening through consolidation). SNF effectively submits that there was no basis for concluding that the skilled addressee would have so read the Patents. Dr Farrow may have so read them, but SNF submits that her Honour found that he was not merely a skilled addressee. He had knowledge well beyond that of the skilled addressee. SNF concedes that he was qualified to give evidence as to the knowledge of the skilled addressee but submits that, on the construction question, he actually gave evidence of his own knowledge and views, and not those of the skilled addressee. The distinction may sound somewhat arcane, but it lies at the heart of the patenting process. 42 It is important to keep in mind that both Professor Slatter and Dr Farrow gave evidence relating to issues other than the construction issue. It is no part of SNF's appeal that Dr Farrow was unqualified to give expert evidence, or that all of his evidence was irrelevant. Insofar as concerns the construction point, the submission is simply that his evidence did not go to the knowledge and understanding of the skilled addressee. 43 In effect Ciba's case is that the skilled addressee would have understood the word "rigidification" and cognate words as necessarily involving the production of networked solids. Her Honour accepted that proposition. Although not overtly, Ciba puts its case on construction in this way: claim 1 describes an improved process of rigidification of material whilst retaining fluidity during transfer; the SNF process admittedly infringes upon claims 1 to 5, if they are valid; persons who are, or may be skilled addressees recognize that the SNF process produces a stacking effect and the rapid release of water, results which are identified in the Patents as flowing from the claimed invention; Dr Farrow considers that these characteristics result from the formation of a networked (or chemically bonded) solid; the skilled addressee would understand the word "rigidification" to mean a process producing stacked solids and the rapid release of water; hence rigidification necessarily involves production of the networked effect; processes of settlement and sedimentation do not produce a networked effect; and hence they do not produce rigidification as that term is used in claim 1. 44 If this is a fair summary of Ciba's approach, as I believe it is, then such approach: is almost totally divorced from the content of the claims and the body of the specification; and overlooks the fact that claim 3 (but not claim 1) expressly incorporates the feature of stacking, and that claim 5 (but not claim 1) expressly incorporates the features of dewatering and improved water quality, suggesting that these characteristics are not incorporated into the notion of rigidification in claim 1. 45 The primary question on appeal is as to whether the evidence, especially that of Dr Farrow, supports her Honour's conclusion as to the meaning of the word "rigidification". SNF submits that such evidence was not as to the understanding and knowledge of the skilled addressee and so does not support the finding. As far as I can see: none of Dr Farrow's evidence, to which the primary Judge refers in connection with the construction question, expressly addresses the knowledge and understanding of the skilled addressee as to the meaning of the word "rigidification"; none of the other evidence to which we have been referred on the question of construction addresses the skilled addressee's understanding of the word "rigidification"; and despite the clear assertion by SNF that there was no evidence as to the skilled addressee's understanding of the word "rigidification", Ciba has not pointed to any such evidence, other than generalized references to the evidence of Dr Farrow, Mr Schroeter and Mr Bembrick. 46 I should point out that at [15] the primary Judge said: There were numerous objections to the experts' affidavits. As indicated at trial, I have dealt with these objections on the basis that in general they affected weight rather than admissibility. It should be presumed that I have found the expert evidence to which I refer below admissible.

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DID DR FARROW GIVE EVIDENCE AS TO THE KNOWLEDGE AND UNDERSTANDING OF THE SKILLED ADDRESSEE? 47 At [75], her Honour observed that Dr Farrow's evidence assisted "in understanding the chemistry and practical effect" of the claimed invention and: … focussed attention on the teaching of the specification as a whole and, when viewed in this way, the teaching in the specification made clear what was meant by a "process of improving rigidification" … . and other terms used in the claim. 48 A reading of the reasons for judgment discloses no reference to any evidence from Dr Farrow which expressly purported to deal with the state of knowledge of the skilled addressee, as opposed to his own views. This position is to be contrasted with the primary Judge's summary of the evidence as to sufficiency at, for example, [247]. As far as can be discerned from the reasons and the evidence to which we were referred on appeal, no other witness gave evidence to the effect that the skilled addressee would have understood the term "rigidification" necessarily to involve the networking of solids. Ciba points to observations made by Messrs Bembrick and Schroeter as to the performance of the SNF process, submitting that their observations of rapid settling, the formation of stacks and the rapid release of relatively clear water describe characteristics of the operation of the claimed invention as described in the Patents. Ciba submits that the witnesses were able to distinguish between these observations and processes involving settlement and sedimentation. Dr Farrow's evidence is used to justify the assertion that these witnesses' observations reflect the claimed invention as described in the Patents and to explain the observations by reference to the networking effect. Ciba submits that for these reasons it should be inferred that the skilled addressee would have understood the term "rigidification", as used in the Patents, as describing either the claimed invention, or its result, or the benefits of such results, or all three. I have difficulty in understanding why that should be so, particularly as neither stacking nor water production is mentioned in claim 1. In the body of the specification, both aspects are treated as being preferred features. 49 On appeal the Court was not provided with all of Dr Farrow's evidence. We have two affidavits, the Notes of Supplementary Evidence, to which I have previously referred, and some parts of his oral evidence. Dr Farrow deals with the question of construction primarily in his affidavit filed on 24 July 2009. At para 22 he refers to various terms or expressions "understood in the industry" and then seems to set out his own understanding of those terms. Thus at para 22(iv) he states: "rigidification" and "rigidify" are qualitative terms describing the strength and characteristics of the tailings material deposited in a deposition or impoundment facility. I discuss this term in more detail later in this affidavit. 50 At paras 32-35, in discussing claim 1, he discusses rigidification. At para 32 he states: "I am aware of this term and it has been used in the industry". He then continues: … I consider, in the context of the Patents, rigidification to be a qualitative term describing the strength and characteristics of the tailings material deposited in the deposition or impoundment facility. A term widely used to describe the strength of the solid-liquid suspension is its rheology. 51 None of this is particularly controversial, but none of it is said to reflect the understanding of the skilled addressee. At para 33 Dr Farrow purports to identify the characteristics of rigidification as they are set out by the primary Judge at [62], namely that the solids will: be less likely to spread laterally; more rapidly form a solid structure in the form of a beach or stack; have greater yield stress; have increased uniformity or homogeneity of fine and coarse particles; involve downward compression forces exerted by the beach or stack; and show more rapid and improved clarity of water release. 52 I have previously referred to the comparative terms used and to the fact that the comparison is apparently with the qualities of the product of a process of settlement and sedimentation. It is difficult to understand how Dr Farrow moved from a description of rigidification, which depended upon such comparative characteristics, to the conclusion that rigidification "can be contrasted to" the process of flocculation leading to sedimentation. One might think that in describing rigidification he was describing a quality which could be present in varying degrees in tailings deposited by different methods. Further, there is no suggestion that he was addressing the views of the skilled addressee rather than conveying his own opinions. 53 In Dr Farrow's Notes of Supplementary Evidence, under the heading "Issues surrounding whether the process of flocculation, settling and sedimentation leading to rigidification is substantially different to flocculation leading directly to rigidification", he conceded that consolidation of sediment would bring about increased yield stress. Indeed, the heading suggests that the process of settling and sedimentation produces a degree of rigidification. He then said: This issue was highlighted in Slatter 2 in numerous locations. For example Paragraph 14, c) "the process of flocculation and settling will always lead to rigidification and Paragraph 31 "…… my explanation of the terms flocculation, sedimentation, settling and rigidification given at Paragraph 14 above. I believe rigidification will most likely occur in all situations given enough time.". In his oral evidence, Professor Slatter at T 408:41-2 said, in relation to the structure of individual aggregates (also called flocs) settled on the bottom of a tailings dam that "I believe that once they touch each other there will be some mechanism by which they are linked". I do not agree that this will lead to the formation of a structure that is the same as that formed by a "beaching" as that term was used by Professor Slatter and as shown in the video. It is true that flocculation and settling in an environment with a fixed base (eg a cylinder or a walled tailings dam or pond) will lead to the formation of a denser (consolidated) sediment due to the compactions force exerted as material accumulates on top of previously settled material. This sediment will often have a higher yield stress than the original feed suspension (eg thickener underflow) which will slowly increase with time. The extent of densification will increase as the sediment height increases (i.e. the compaction force), but only up to a point. The long-term characteristics of sediment formed by settling then consolidation will be very different to the characteristics of the same feed material that has been "beached". A sediment formed by settling/consolidation will comprise flocs that initially settled, then stop as they reached the top of the sediment bed. At this point they will not have undergone any dewatering during the settling process. As the settled aggregates are covered by more settled aggregates they will start to experience a force due to the weight of the overlying material. This will induce only limited densification of the aggregates [Refer to Farrow et al paper exhibit PS-1 (CB 2174) to Slatter 2, page 146 (CB 2179), 2nd paragraph that states "It is notable that …. Passage through the bed down to a depth of 300 mm had not substantially altered their structure from that formed during flocculation". This is saying that compression forces in this situation did not densify the aggregates despite the solids concentration increasing from 4.3 wt% (feed concentration) to 13.6 wt% (at 0.3 m depth).] This shows that, initially, the increase in solids concentration within a bed formed from settled material arises due to closer packing of the aggregates and not from any significant densification. As the bed builds up, the aggregates within the bed will be forced closer together and will entangle. They will not bond together (there is no driving force for flocculant that is binding aggregates together to desorb from a surface and re-adsorb on the surface of a different aggregate that may now be in close proximity. However, entanglement of aggregates (which have an extremely asymmetric three-dimensional structure) will make it difficult to disentangle individual aggregates from one another. Consequently a sediment formed by flocculation, settling and consolidation will have a yield stress but this is due to entanglement of individual aggregates and not due to networking of the entire solid mass. The same will occur for unflocculated solids in a concentrated suspension. If they are packed close enough together (i.e. the solids concentration is sufficiently high) they [sic] because of their asymmetry and surface roughness they will interlock and resist an applied force - thus exhibiting a yield stress. In contrast, the '944 process commences with networking of the solids within the tailings stream, this is a process termed rigidification within '944. This is, in my opinion, an entirely different process to that of settling and consolidation. 54 This document seems to contain Dr Farrow's first reference to the networking effect. Dr Farrow accepted that the product of a process of settlement and sedimentation might develop increased yield stress as the result of compaction. As the primary Judge accepted (at [69]) that "rigidification" was a "process of developing strength (in terms of yield stress)", it follows that the process of settlement and sedimentation is a process of rigidification. Such process yields a product which is more solid than the slurry and will continue to rigidify as it compacts. The basis for Dr Farrow's distinction between the process of settlement and sedimentation and the claimed invention seems to be the absence of networking in the product of the former, a matter which is not expressly disclosed in the Patents. 55 Dr Farrow then described his understanding of the claimed invention, largely by reference to observations of the operation of the SNF process. He concluded at p 4: I also note the following comment from Professor Slatter at T 387:9-15 in response to Shavin's question: "Isn't that process of bridging the network between the particles will [sic] high doses of flocculant the concept of rigidification disclosed in this patent?--- Having been led through the questions, I believe that rigidification, the strength - rigidification to be the development of strength, which, in my language, would be the development of a yield stress - will occur with or without polymer particles present. I am convinced that the addition of certain polymers would speed up the process, but that process of rigidification I do not see as a separate scientific phenomenon from what would happen over time in any event". I respectfully disagree. Professor Slatter appears to me to be taking a very narrow view of what is [sic] rigidification is. My understanding of the term in the context of the teachings of the patent, as I have described above, is that the outcome of rigidification will be a process producing a different tailings deposit, with different characteristics, different dewatering potential in a quite different period of time to natural settling and sedimentation processes. 56 I would have thought that it was Dr Farrow who was trying to narrow the meaning attributable to the word "rigidification" by insisting upon presence of the networking effect. 57 In any event the concluding paragraph demonstrates that Dr Farrow was not giving evidence as to any specialized meaning of the word "rigidification", whether according to his own understanding or that of the skilled addressee. He was rather giving evidence as to his construction of the patent in which he attributed a special and, I suggest, narrow meaning, allegedly dictated by the "context", but with no reference to any particular part of the document. He simply chose to use the word as describing only the outcome which the patentee seeks to achieve by the claimed invention or, perhaps, the results achieved by the SNF process. In any event, as far as I can see, there is no suggestion that a skilled addressee, as opposed to a scientist such as Dr Farrow, would so understand the term. 58 The consequences of Dr Farrow's approach to the meaning of the term "rigidification" appear in his affidavit filed on 9 November 2009. He treated various items of prior art as irrelevant to the questions of anticipation and innovation on the basis that such items involved settlement and sedimentation. The primary Judge adopted that approach. 59 In some circumstances, one might assume that the parties had conducted the case at first instance upon the basis that Dr Farrow's evidence was tacitly directed towards the knowledge and understanding of the skilled addressee. References to use of the term in the industry, although without any direct assertion as to the knowledge or understanding of the skilled addressee, might be treated as suggesting as much. However it seems that the case was not conducted in that way. In the notice of appeal SNF specifically challenges her Honour's construction of the term "rigidification", attributes her error to the adoption of Dr Farrow's evidence and asserts that such evidence was not as to the way in which a skilled addressee would have understood the specification. SNF's submissions concerning construction are at paras 8 to 16 of its outline. At para 16, it submits: These submissions were made at length at trial (Applicant's closing submissions at trial, pars 8-26) and, it is submitted, were not given proper consideration in the trial judgment. It is therefore submitted that the trial judge erred in her ultimate construction of the term "rigidification"; this error, moreover, has an impact on the balance of her decision in relation to the issues of novelty, innovative step and sufficiency of description (see further below). 60 I infer that the primary Judge's remarks at [15], concerning admissibility of evidence, referred to these matters. Clearly, the question is at the core of the appeal.

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CIBA'S RESPONSE ON APPEAL 61 In my view, Ciba has simply not responded to SNF's challenge to the primary Judge's acceptance of Dr Farrow's evidence as going to the understanding of the skilled addressee. In order to demonstrate my reasons for reaching this conclusion, it is necessary that I deal in some detail with Ciba's submissions, both written and oral. 62 At paras 11-29 of its written outline, Ciba refers to a number of principles of construction which are broadly favourable to a finding of validity and asserts that the primary Judge's approach was "wholly consistent with these principles". It observes that the primary Judge recognized that "although 'rigidification' is not a term of art, it was necessary to determine what the word signified in the context of the specification and claims of the Patents …". Ciba submits that the ordinary meaning of a word may vary by virtue of the context in which it is used, and that her Honour found that the "industrial context" in which the word was used was such that expert opinion was admissible and appropriate. Ciba then submits that at the trial, SNF relied heavily on its own expert (Professor Slatter) in advancing its preferred construction of the term "rigidification", and that "It is not now open to the appellant to contend that the primary judge erred by considering expert evidence on the question". However SNF does not complain about the receipt of expert evidence on the construction question. It simply submits that such evidence should have been as to the meaning which the skilled addressee would have attributed to the term in question at the relevant time. That proposition is amply supported by the decision in Glaverbel SA v British Coal Corporation [1994] RPC 443 at 486, upon which decision the primary Judge relied. Mummery J said at ll 41-46: It was for the Court, not for any witness, however expert, to decide the question of construction in accordance with the meaning of the language used. Experts could give evidence to enlighten the judge on the meaning which those skilled in the art would give to technical or scientific terms and phrases and on unusual or special meanings given by such persons to words which might otherwise bear their ordinary meaning. … 63 At para 15 of its outline, Ciba submits that SNF seeks to establish that rigidification includes the processes of settling and sedimentation, and that "[Patent 944] sought from the outset" to distinguish between such processes and the claimed invention. Ciba seems to have sought, at trial, to establish that rigidification was not a term which could properly be used to describe a process of settlement and sedimentation. SNF's position seems to have been, and to be, that in considering the prior art, such processes should at least be examined to see if they disclose all of the integers of the claims, and that they should not be excluded from such examination by the attribution of an unnecessarily narrow meaning to the word "rigidification", or by use of the term "settlement and sedimentation" as a mantra, the use of which excludes otherwise relevant items of prior art. Ciba submits that her Honour's preference for the evidence of Dr Farrow over that of Professor Slatter should be respected. I accept that proposition, but the question is whether Dr Farrow's evidence went to the knowledge and understanding of the skilled addressee. 64 Ciba then defines the hypothetical skilled person as "a person acquainted with the surrounding circumstances of the state of the art and manufacture at the relevant time", refers to the primary Judge's description of the skilled addressee and asserts that Dr Farrow satisfied these requirements and could therefore give relevant evidence on construction. These matters are not in dispute. However SNF submits that the evidence which Dr Farrow gave was as to his own views, not those of the skilled addressee, and that such views were informed by knowledge and experience beyond that of the skilled addressee. 65 At paras 21 and 22 of its written submissions, Ciba summarizes Dr Farrow's evidence and submits that his conclusions "accord completely with the evidence of Mr Bembrick in relation to the SNF Process, an embodiment of the patented process". It may well be that Dr Farrow considered that Mr Bembrick was describing characteristics similar to those to be produced by the claimed invention, but it is not suggested that Mr Bembrick had any particular understanding of the word "rigidification" or offered any evidence as to that matter. Further, whilst the SNF process may fall within the boundaries of the claims, assuming that they are valid, it may well lie at the very centre of the claimed territory. SNF's attack upon the claims may deal with more marginal areas. The point of the construction exercise was to determine the territory claimed so that the validity of the Patents could be determined by reference to the prior art. Similar comments apply to Ciba's attempts to rely upon the evidence of Mr Schroeter concerning the SNF process. 66 At para 24 of the outline Ciba addresses another central aspect of the construction issue: requirement of a networked structure as a condition of rigidification. Ciba submits that there is nothing in the specification which is inconsistent with "such an approach". It asserts that Dr Farrow simply provided an "expert chemist's explanation of why rigidified material behaved differently to material obtained by settling and sedimentation". Further it submits that "practical people working in the field" were able to recognize rigidified material "even if they did not understand, as a matter of chemistry, why rigidified material had such advantageous properties", a reference to the evidence of Mr Bembrick, Mr Schroeter and, perhaps, others. Ciba's submission seems to be that the evidence of Messrs Schroeter and Bembrick concerning their observations of the SNF process necessarily demonstrates the networking effect identified by Dr Farrow. Further, it is said to follow that, as her Honour concluded, networking (chemical bonding) is a necessary integer of the claimed invention, notwithstanding the absence of any reference to it in the body of the specification or the claims. 67 At [69] the primary Judge concluded that rigidification was "a qualitative term, in which a networked structure is formed". The word "qualitative" (used by Dr Farrow) means (OED) "relating to, connected or concerned with, quality or qualities". The OED also indicates that the word is usually used in implied or expressed opposition to the word "quantitative", suggesting a concern with quantity. I do not fully understand the meaning intended to be conveyed by Dr Farrow in using the word "qualitative". As best I can ascertain, he meant that the word "rigidification" is used to imply the creation in the relevant material of a degree of rigidity, but not any particular degree. This approach is difficult to reconcile with the comparative terms used in describing the characteristics of rigidification to which I have previously referred. 68 Ciba submits (at para 27) that SNF's submissions pay insufficient regard to integer (d) of Claim 1 which prescribes the addition of "an effective rigidifying amount" of flocculant. This submission seems to mean that the effective rigidifying amount is the amount necessary to produce the "type of effect described in [Patent 944] at pp 13 and 14". The results discussed on those pages are associated with a preferred embodiment of the claimed invention in which the flocculated slurry flows over the surface of previously rigidified material, then stands and, itself, rigidifies. The process is repeated, forming "stacks" which impose higher downward compaction pressure "enhancing the rate of dewatering". As I have previously pointed out, stacking and dewatering are integers of claims 3 and 5 respectively, but not of claim 1. This suggests that neither "stacking" nor "dewatering" are necessary elements of rigidification as that word is used in claim 1. I shall return to this question. 69 At para 28 Ciba submits that SNF's references to networking as a "pre-condition" or a "key or distinguishing feature of rigidification", and assertions that "rigidification means networking" "proceed on a misapprehension of the evidence, the Patents and the primary Judge's reasons". This submission is in response to SNF's submission at par 15 of its outline that Patent 944 refers to results and says nothing about networking. Ciba then submits: (b) The non-chemist skilled addressee needs to know nothing about "networking" to work the invention; as submitted below with respect to sufficiency, the evidence was that practical people routinely undertook testing of the kind necessary to implement the process successfully. (c) Dr Farrow's evidence on "networking" merely confirmed, and provided a scientific underpinning to, what practical people already knew: rigidified material obtained from the patented process is materially different to settled material. 70 This submission seems to go more to sufficiency than construction. Further, as I have observed, her Honour, at [69], found that "rigidification" is "a process of developing strength (in terms of yield stress)" and "is a qualitative term, in which a networked structure is formed". In other words, it is a necessary aspect of the invention that a networked structure is produced. On this basis the absence of networking is used to exclude settlement and sedimentation processes from the prior art base. If networking is not a necessary aspect of the claimed invention, then the finding is wrong. It is no answer to say that the Patents describe the effects to be produced, and so the requirement for networking is implicitly included in the meaning of the term "rigidification", at least in the absence of evidence that the skilled addressee would understand that such effects could not be produced in any other way. It is true that at least one industry witness said that his observation of the SNF process suggested that it was different from settlement. However he was not speaking about his understanding of the term "rigidification". Further, the differences in question seem to have been the stacking effect (which has never been defined) and the enhanced yield of water of improved purity. However it is not said that either is exclusively produced by the networking effect. Hence it is difficult to understand her Honour's conclusion that networking is a necessary aspect of rigidification as that term is used in the Patents. 71 The difficulty produced by Ciba's approach is demonstrated by the use to which Dr Farrow's evidence is put in this case. The absence of networking is used as a basis for treating processes of settlement and sedimentation as being different from the claimed invention and, on that basis, excluded from the prior art base. That conclusion is reached notwithstanding the fact that the claimed invention is said to be an improvement on processes involving settlement and sedimentation, involves similar treatment to that involved in those processes, possibly with variations, and is said to involve "deposition" and/or "settlement" areas. I do not mean to prejudge questions of novelty and invention. I observe only that the exclusion of processes involving settlement and sedimentation from the prior art base seems an unlikely result, given the absence of any reference to networking in the Patents, the comparative terms used to define the word "rigidification" and the structure of claims 1, 3 and 5 of the Patents. 72 At para 29 Ciba submits that the primary Judge's conclusion, that the process of improved rigidification did not encompass settling and sedimentation, was plainly open to her. Such a submission implies that her Honour's conclusion should be treated as beyond challenge on appeal because it was "available" on the evidence. Decisions as to construction do not enjoy such immunity, even when they are informed by expert evidence. Her Honour's preference for the evidence of Dr Farrow over that of Professor Slatter must be respected, but that does not place her Honour's construction beyond appeal. In determining such appeal this Court must have regard to that evidence, the way in which her Honour used it and the rules of construction applicable to patents. 73 The question is not whether, as a scientific fact, "rigidification" is a word which includes settlement or sedimentation. The question is as to how the skilled addressee would have understood the term "rigidification" as used in the Patents. That question is not to be resolved by reference to Dr Farrow's own opinions as to the meaning of the word or as to the proper construction of the Patents, nor by reference to those of Professor Slatter. The Court must address the position of the skilled addressee. SNF's point is that there was no clear evidence as to how the skilled addressee would have read the Patents and, in particular, would have understood the word "rigidification" and the term "a process of improving rigidification". In the absence of such evidence, her Honour could only give the words their ordinary meanings. 74 I turn to Ciba's oral submissions concerning the construction question. Counsel commenced with the statement that: … In understanding this case, it's very important to understand not only what the first part of the first integer of the claim 1 is, which is the only part of claim 1 that our friends have sought to rely upon, but to understand what, in fact, was the debate between Dr Farrow and Professor Slatter, what was the debate as to the underlying disclosure in this patent, what was the context in which claim 1 as a whole should be looked at and understood as forming part of … . 75 At p 82 ll 1-5 counsel said: And thus it is … very important, in our respectful submission, for the court to be able to distinguish between that process of settling and sedimentation acknowledged in the body of the specification as part of the prior art and that which is claimed. 76 Ciba's oral submissions focussed very much upon Dr Farrow's evidence and her Honour's preference for it over that of Professor Slatter. However, at no point did it identify any clear evidence from Dr Farrow as to the understanding of the skilled addressee. Counsel also referred extensively to the evidence of Mr Schroeter who was accepted as a skilled addressee. However the references were to evidence concerning his observations of the SNF process. Mr Bembrick may also have been a skilled addressee, but his evidence was similarly descriptive of the SNF process. As I have said we were referred to no evidence from either Mr Schroeter or Mr Bembrick concerning his understanding of the term "rigidification" in the Patents. Counsel also referred to evidence from Mr Woolley and Mr Coleman describing a process used at the Londonderry sand mine, a pleaded example of prior publicly available information. Again it is not clear to me that such evidence can assist in construction of the Patents. 77 As far as I can see, Ciba has simply not addressed SNF's submission concerning evidence as to the meaning of the term "rigidification". It has rather focussed upon the alleged distinction between the SNF process (and, by implication, the claimed invention) on the one hand, and processes involving settlement and sedimentation on the other, a distinction which does not seem to arise out of the Patents themselves. Given that SNF has clearly challenged the primary Judge's reliance on Dr Farrow's evidence in construing the Patents, upon the basis that such evidence did not go to the knowledge or understanding of the skilled addressee, one would have expected Ciba to have identified any part of the evidence which directly addressed such knowledge and understanding. It did not do so. 78 Finally, I observe that the primary Judge's reasons for preferring the evidence of Dr Farrow to that of Professor Slatter (at [69]-[75]) suggest that her Honour was not addressing a conflict in their evidence as to the knowledge and understanding of the skilled addressee, but a dispute as to personal scientific opinion. Her Honour's treatment of the construction point is to be contrasted with her treatment of common general knowledge. At [185] and [186], her Honour set out in some detail the evidence of those recognized as being skilled in the art. Similarly, in addressing the question of sufficiency, her Honour referred to evidence from both Professor Slatter and Dr Farrow, addressing the position of the person skilled in the art. 79 The primary Judge's reasons suggest that her consideration of the construction question was dominated by Ciba's attempt to demonstrate that the claimed invention was different from processes involving settlement and sedimentation. It sought to do so primarily by reference to the evidence of Mr Schroeter and Mr Bembrick in describing the SNF process, and to Dr Farrow's evidence explaining those observations. However it seems that neither Mr Schroeter nor Mr Bembrick gave evidence directly bearing on the construction questions. In my view Ciba sought to construe the word "rigidification" in the context of the claimed invention, as understood by Dr Farrow, but neglected the words of the Patents. There is a risk of circuitousness in using a known word to describe a new process, and then seeking to redefine the word by reference to that process. This is the problem identified by Lord Hoffmann in the passage cited above. Finally, as I shall attempt to demonstrate, reference to the body of the specification of Patent 944 establishes that the word "rigidification" is used with its ordinary meaning. 80 I conclude that the primary Judge erred in receiving and acting upon the evidence of Dr Farrow as to his understanding of the meaning of the term "rigidification" and associated terms. The evidence was inadmissible because it was irrelevant to the proper inquiry which was as to the relevant knowledge and understanding of the skilled addressee. Part 3.3 of the Evidence Act 1995 (Cth) has no relevant effect on the position.

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THE WORDS "RIGID", "RIGIDITY" AND RIGIDIFICATION" 81 In the absence of any helpful evidence concerning the knowledge and understanding of the skilled addressee, the construction exercise must focus on the words of the Patents and the ordinary meaning of the relevant words. My approach to this task does not involve reliance upon the evidence of either Professor Slatter or Dr Farrow. Although I accept the primary Judge's identification of the dictionary definitions of these words, I should say a little more about them. The word "rigid" is defined as "stiff; not pliant or flexible; firm; hard". The verb "rigidify" may be either transitive or intransitive. In its transitive form it means "to make rigid". In its intransitive form it means "to become rigid". The word "rigidification" means "the action of making or becoming rigid". It is to be distinguished from the word "rigidity". The latter word means "the state of being rigid; stiffness, hardness". Some of these definitions may suggest that both "rigidity" and "rigidification" are absolute, rather than comparative terms. However the OED suggests that comparative usage is also possible. The Patents suggest as much. Thus, in transitive usage, the word "rigidify" means "to make rigid" or "to make more rigid". In intransitive usage, the word means "to become rigid" or "to become more rigid". 82 Claim 1 of Patent 944, upon which the other claims depend, speaks of "improving rigidification of a material", meaning that the degree of "making or becoming rigid" is to be increased. The primary Judge concluded, at [46], that: … the word "improve" necessitates a comparison here with processes other than the claimed process. As the Ciba respondents noted, neither the claims nor the specification assert that 'rigidification' of tailings is the 'invented' process. 83 Patent 944 commences with a description of the disposal of tailings in mining operations. In underground mines, tailings may be used as backfill. In such cases, the tailings may be pumped into the mine as slurry, usually containing a high proportion of large-sized particles. It is then left to dewater, leaving sedimented solids in place. A flocculant may be used to increase the rate of sedimentation. Larger particles will settle more quickly than finer particles, resulting in an heterogeneous deposit of coarse and fine solids. Waste cannot always be used as backfill. An alternative method is to pump it, as a slurry, to lagoons, heaps or stacks and allow it to dewater gradually through the actions of sedimentation, drainage and evaporation. There is a need to minimize such use of land and to use existing waste areas more effectively. One method of achieving this outcome is to "load multiple layers of waste onto an area to thus form higher stacks of waste". This method presents the difficulty of ensuring that: the waste material can only flow over the surface of previously rigidified waste within acceptable boundaries, is allowed to rigidify to form a stack, and that the waste is sufficiently consolidated to support multiple layers of rigidified material, without the risk of collapse or slip. Thus the requirements for providing a waste material with the right sort of characteristics for stacking is altogether different from those required for other forms of disposal, such as back-filling within a relatively enclosed area. 84 In a typical mining operation, waste solids are separated from mineral products in an aqueous process, producing an aqueous suspension of waste solids. The solids may be concentrated by flocculation and pumped to a surface holding area, often called a tailings pit or dam. Once deposited there, water continues to be released, resulting in further concentration over time. Such a dam usually has a gently sloping bottom which allows any water released from the solids to collect in one area so that it can be pumped back to the plant for re-use. Fine particles may be carried away with the run-off water, contaminating it and creating a detrimental impact on its suitability for subsequent use. 85 It is desirable that coarse and fine waste particles be disposed of as a homogenous mixture, improving both the mechanical properties of the dewatered solids and greatly reducing the time and cost of rehabilitating the land. Achievement of this aim is not usually possible because the larger particles settle more quickly than the smaller particles. Further, where the proportion of coarse material is relatively high: the rapid sedimentation of the coarse material may produce excessive beach angles which promotes the run-off of aqueous waste containing high proportions of fine particles, further contaminating the recovered water. As a result, it is often necessary to treat the coarse and fine waste stream separately, and recombine these material [sic] by mechanically re-working, once the dewatering process is complete. Attempts have been made to overcome all the above problems by treating the feed to the tailings dam using a coagulant or a flocculant to enhance the rate of sedimentation and/or improve the clarity of the released water. However, this has been unsuccessful as these treatments have been applied at conventional doses and this has brought about little or no benefit in either rate of compaction of the fine waste material or clarity of the recovered water. 86 To this point, the specification is discussing processes which involve settlement and sedimentation. The words "sedimented" and "sedimentation" are frequently used (p 1 ll 18, 20, 21, 27 and p 3 ll 9 and 18). The general tenor of the discussion at, for example, p 2 ll 9-19, 25-28 and p 3 ll 7-14 and 16-21, similarly suggests that view. In that context the words "rigidify" and "rigidification" are also used, for example, at p 2 ll 1, 2 and 3. The reference to "concentration" (p 2 l 17) also suggests rigidification. It might be suggested that the paragraph commencing at p 1 l 32 and concluding at p 2 l 7 is not discussing settlement and sedimentation processes. However the subsequent discussion on pp 2 and 3 is clearly about such processes, suggesting that all of the foregoing discussion concerns processes of that kind. Thus Patent 944, itself, attributes the production of rigidification to settlement and sedimentation processes. 87 At p 3 ll 23-28, Patent 944 asserts that: It would therefore be desirable to provide treatment which provides more rapid release of water from the suspension of solids. In addition it will be desirable to enable the concentrated solids to be held in a convenient manner that prevents both segregation of any coarse and fine fractions, and prevents contamination of the released water whilst at the same time minimises the impact on the environment. 88 At p 3 l 30 and following, the "Bayer process" is discussed. It involves the recovery of alumina from bauxite. It is a settlement process (see p 4 ll 12 and 13). The reference at p 4 l 13 to "prolonged settlement" suggests that it is a process of settlement and sedimentation. At p 4 ll 17-20 it is said that: The mud can be disposed of and/or subjected to further drying for subsequent disposal on a mud stacking area. To be suitable for mud stacking the mud should have a high solids content and when stacked, should not flow but should be relatively rigid in order that the stacking angle should be as high as possible so that the stack takes up as little area as possible for a given volume. The requirement for high solids content conflicts with the requirement for the material to remain pumpable as a fluid, so that even though it may be possible to produce a mud having the desired high solids content for stacking, this may render the mud unpumpable. (emphasis added) 89 Hence Patent 944 describes the product of this process as having a degree of rigidity and, indeed, a capacity to be stacked. 90 The specification then discusses Patent EP-A-388108 which is said to describe: … adding a water-absorbent, water insoluble polymer to a material comprising an aqueous liquid with dispersed particulate solids, such as red mud, prior to pumping and then pumping the material, allowing the material to stand and then allowing it to rigidify and become a stackable solid. The polymer absorbs the aqueous liquid of the slurry which aids the binding of the particulate solids and thus solidification of the material. (emphasis added) 91 The Patent 944 specification identifies two problems with this process. First, it requires high doses of the polymer. Second, although there may be "an apparent increase in solids", the aqueous liquid is in fact held within the absorbent polymer. This presents a disadvantage in that the aqueous liquid may, under certain circumstances, be subsequently desorbed, creating a risk of re-fluidization of the waste material and de-stabilization of the stack. The reference to "allowing the material to stand and then allowing it to rigidify" does not suggest the almost immediate rigidification which is said to occur in the SNF process and, as Ciba submits, the claimed invention. It is not clear whether Ciba classifies this process as one of "rigidification" or "settlement and sedimentation". The word "rigidify" is frequently used, but it seems that the rapid production of water is not a significant characteristic. 92 The Patent 944 specification then addresses Patent WO-A-96/05146 which is referred to in the primary Judge's reasons as "Slatter 4". It describes: a process of stacking an aqueous slurry of particulate solids which comprises ad-mixing an emulsion of a water-soluble polymer dispersed in a continuous oil phase with the slurry. 93 Concerning this patent, the specification states: Preference is given to diluting the emulsion polymer with the diluent, and which is preferably in a hydro carbon liquid or gas and which will not invert the emulsion. Therefore it is a requirement of the process that the polymer is not added in to the slurry as an aqueous solution. 94 Patent WO-A-0192167, referred to in the primary Judge's reasons as "Slatter 3", is said to describe: 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 (whilst) being pumped, but upon standing causes the material to rigidify. 95 The Patent 944 specification states that the Slatter 3 process facilitates the easy stacking of solid material and releases water, but that it emphasizes "the importance of using particles of water-soluble polymer". It also observes that Slatter 3 states that "the use of aqueous solutions of the dissolved polymer would be ineffective". That observation may not accurately report the relevant passage in Slatter 3. I shall return to that question. The Patent 944 specification then asserts that notwithstanding the improvements brought about by Slatter 3, there is still a need "to further improve the rigidification of suspensions of materials and further improve upon the clarity of liquor released". The objectives of the claimed invention are said to be: to find a more suitable method for treating coarse and/or fine particulate waste material in order to provide better release of liquid and a more effective means of disposing of the concentrated solids; and to improve the dewatering of suspensions of waste solids that have been transferred to a settling area for disposal and provide improvements in the clarity of run-off water. 96 The claimed invention is then explained in some detail. It is said to be a process of improving rigidification whilst retaining fluidity during transfer. The process involves an aqueous liquid with particulate solids, being transferred as a fluid to a deposition area, and there allowed to stand and rigidify. The process involves addition to that liquid, during transfer, of an "effective rigidifying amount" of an aqueous solution of a water-soluble polymer, having an intrinsic viscosity of at least 5 dl/g (measured in 1M NaCl at 25oC). Such addition is said to allow retention of fluidity during transfer, and until the fluid is allowed to stand. The fluid will then form a solid mass, strong enough to support subsequent layers of rigidified material. Such addition does not cause instant rigidification or any settling prior to standing. Appropriate dosages of the polymer may vary greatly. Although the slurry may contain both coarse and fine material, better results are obtained where the solids are relatively concentrated and homogeneous. Usually, lower concentrations of the polymer are desirable. The reference to a "deposition area" and to there being no settling "prior to standing" may be relevant to the construction question. I note that at p 6 ll 15-16 the term "settling area" is used, suggesting that settlement may not be completely irrelevant in a description of the claimed invention. 97 Preferably, the slurry, after addition of the polymer, should be allowed to flow over rigidified material and allowed to stand. It will rigidify, forming stacks based on the previously rigidified material. It is important that there be no settlement during transit, and that, whilst the fluid is standing, flow be minimized in order that solidification can proceed rapidly. The heaped geometry and the "co-immobilization" of fine and coarse material will facilitate the release of water, perhaps because of downward compaction pressures. I note that at p 15 l 28 and p 16 l 6, the term "settling area" is again used in connection with the claimed invention. In argument, reference was made to photographs which appear in Patent 944. It is difficult to discern much from them except that they demonstrate the stacking effect. 98 I turn to the construction of the words "rigidification", "rigidify" and "a process of improved rigidification". A further question is the meaning of the words "stand and rigidify". Another may be the meaning of the term "deposition area". As I have demonstrated, those words, or associated words are used in the body of the specification. For the moment, I shall focus on claim 1 and the body of the specification. However it seems probable that the meaning of the words "rigidification" and "rigidify" in claim 1 will be consistently reflected in the use of the same and cognate words in the other claims. 99 The word "material", appearing twice in integer 1, must mean the slurry described in integer 1(b). The aim of the process referred to in integer 1(a) is to improve rigidification of the slurry, that is to improve the process by which the slurry becomes more rigid. Fluidity of the slurry is to be retained during transfer. The slurry is to be allowed to stand and rigidify in the "deposition" area. The word "deposition" is generally used in connection with removal from office or giving evidence on oath. However the OED also includes the following meanings: The action of depositing, laying down, or placing in a more or less permanent or final position … The process of depositing or fact of being deposited by natural agency; precipitation … The result of this process; a deposit, precipitate, sediment. … 100 The word "deposit" is said to mean: To lay, put, or set down; to place in a more or less permanent position of rest. … 101 No doubt there is room for argument but, in this context, the word "deposition" seems to mean something like "settlement" or "sedimentation". As I have observed the words "deposition" and "settlement" are used in connection with the claimed invention. 102 The phrase "stand and rigidify" has acquired some significance in the case. It seems to be accepted that the word "stand" implies that the slurry ceases to flow. This is said to be necessary in order that rigidification proceed. However the two events do not occur simultaneously in that the flow must stop so that the slurry stands, and then rigidifies. If the slurry continues to flow, it may not rigidify or, at least, not to the desired extent. It is said that rigidification must proceed quickly once the slurry ceases to flow. 103 At the risk of over-simplifying things, I would summarize the identified problem to be solved as follows: In a mining operation slurry is piped from the mine to a "deposition area" where it is to be stored, at least temporarily. It is desirable that: the space used for such storage be minimized; and the water released from the slurry be reused, and therefore be suitable for re-use. In the absence of further action, the slurry will stand in a tailings dam where solid particles will settle on the floor of the dam and accumulate, to some extent being compressed so that they achieve a degree of yield stress or solidity. The water will be collected and re-used. However loose solid particles may contaminate it, reducing its usefulness. It is desirable that: solid material be stacked to reduce the area of the tailings dam, but stacking requires that the solid material have sufficient yield stress to enable it to form stacks; water recovery be maximized; and water quality be improved. The process must be conducted so that solids do not settle out of the slurry prior to its being deposited in the tailings dam. The process may be accelerated by use of a flocculant. 104 The claimed invention is said to: avoid premature settlement of solids; bring about rapid de-watering of the slurry once it reaches the tailings dam; produce improved "rigidification" of the solids so that they quickly form stacks, based on previously rigidified material; and in so doing, permit the rapid recovery of water of improved purity. 105 The mechanism by which these results are achieved is: addition of a suitable dosage of a suitable polymer flocculant in solution, to a suitably concentrated slurry containing a suitably homogeneous mixture of solid particles, so that when the slurry ceases to flow, the flocculant binds the particles of solid material into a solid mass, preferably, the slurry is allowed to flow over previously rigidified material, thus forming stacks which stand on the floor of the tailings dam, and preferably, water containing "significantly less solids" runs off. 106 In summary, the evidence discloses that the claimed invention produces a networked, or chemically bonded mass of particles, and that such bonding brings about the desired results. The Patents do not expressly disclose this fact. Ciba says that the claimed invention is to be distinguished from other processes in which particles, often assisted by flocculation, settle on the floor of the tailings dam as individual particles, lacking the yield stress to form stacks. Water is released more slowly and is at risk of contamination by loose particles. It seems that the claimed invention uses the flocculant in a way which produces much larger clumps of material than do other processes, including those using flocculants. 107 I have previously identified the use of the word "rigidified" in Patent 944 in connection with settling and sedimentation (Patent 944 p 2 l 3), and the use of the words "settlement" and "rigid" in connection with the Bayer process. In discussing the claimed invention, the specification also uses the words "deposition area" (Patent 944 p 6 l 25, p 7 l 24 and p 13 ll 13, 16 and 26-27.). At p 7 ll 2-4, the following passage appears: We have unexpectedly found that the addition of the aqueous solution … does not cause instant rigidification or substantially any settling of the solids prior to standing. 108 This sentence certainly distinguishes between rigidification and settlement. However it seems to suggest that in a process of rigidification there will be settlement, presumably of rigidified solids, after standing. At Patent 944 p 15 l 18, there is reference to a "settling area", a term which is arguably synonymous with the term "deposition area". See also l 27 and p 16 l 6. 109 Construction of a patent is not a purely semantic exercise. Nonetheless the words are important. The primary Judge concluded that the "process as taught does not encompass settlement and sedimentation". That proposition, not apparent on the face of the Patents, assumes a precise definition of the words "settlement and sedimentation". No such definition appears from the evidence. The term seems to have been used to describe processes in which solids settle out of a slurry, with or without use of a flocculant, but excluding Slatter 3, Slatter 4, the SNF process and the claimed invention. The distinction is said to lie in the meaning of the word "rigidification", notwithstanding the somewhat promiscuous use of the terms "rigidification", "settlement", "sedimentation" and cognate words in the body of the specification. 110 The precise meaning attributed by the primary Judge to the word "rigidification" is not entirely clear. Her conclusions appear at [69]-[75]. The approach seems to be as follows: rigidification is a process of developing strength (in terms of yield stress); it is a qualitative term in which a networked (chemically bonded) structure is formed; the words "process of improved rigidification" invite comparison with the "process of settlement and sedimentation"; such comparison demonstrates that the claimed invention results in: faster solidification (in that material has greater yield stress); produces more recovered water; and results in chemically bonded tailings that occupy a smaller surface area, which is more quickly rehabilitated; rigidification is to be "understood in this way"; the process as taught does not encompass settling and sedimentation. 111 The process of "rigidification" is said to involve faster solidification, greater water production and networking. The claimed invention is said to do these things faster and better than do processes of settlement and sedimentation. It follows (and the evidence demonstrates) that the latter processes produce some degree of solidification and some water. There is no clear indication as to the point in the continuum at which a process ceases to be one of settlement and sedimentation and becomes one of rigidification. Further, to define rigidification in terms of the extent to which the claimed invention produces better results than do other processes is, in my view, unsatisfactory. It raises the spectre of circuitousness to which I have referred. 112 At trial, Ciba ultimately relied upon the concept of networking and its absence from the sediment produced by processes of settlement and sedimentation. The requirement for networking is, on the evidence, not a matter of degree or comparison. However networking is not mentioned in the Patents. Ciba submits that the networking phenomenon produces the characteristics of solidification and dewatering, but they are also features of settlement and sedimentation processes, although perhaps to a lesser degree. Hence those characteristics offer no basis for distinguishing the claimed invention from processes of settlement and sedimentation. To some extent, Ciba relies on the forming of stacks and the production of water as being unique to the networked outcome. However the Patents treat both as incidents which occur in settlement and sedimentation processes. See Patent 944 at p 1 ll 31-32, p 2 ll 15-20 and p 4 ll 17-18. More importantly, both are only preferred aspects of the claimed invention, thus making it unlikely that either is encompassed by the term "rigidification" in claim 1. 113 Nothing in the body of the specification or in the claims indicates any reason for departing from the usual meanings of the word "rigidification" and cognate words or the phrase "a process of improving rigidification". A process of improving rigidification is a process which develops yield strength. Professor Slatter's lay description of the term as the "development of solid properties" seems to be consistent with the dictionary meaning and the evidence, save that which seeks to attribute to the word "rigidification" the requirement for networking or particular, but unspecified degrees of stacking, water production and water quality. The "material" identified in integer 1 (the slurry) contains both solids and liquid. Solidification or rigidification necessarily involves separation of the solids from the liquid. I see no reason to attribute any narrower meaning to the term. A sufficient degree of rigidity may produce beneficial outcomes such as the capacity to stack, and therefore save space, or the production of water in volumes, and of a quality which will allow its re-use. But there is no basis for using those beneficial characteristics as defining the word "rigidification" in claim 1. They are expressly dealt with in claims 3 and 5. Presumably, the word is used consistently throughout the claims and in the body of the specification. Claims 3 and 5 either limit or expand the territory claimed in claim 1. If they have limiting effects, then claim 1 must claim more than a process which produces stacking and/or the release of liquid with a degree of improved clarity. If claims 3 and 5 expand the territory claimed in claim 1, then claim 1 must not claim the subject matter of claims 3 and 5. In either case, claim 1 cannot be construed as limited to processes which produce stacking and/or water of improved quality or in increased quantities. 114 The word "rigidification" should have its ordinary meaning: the action of making or becoming rigid or more rigid, the word "rigid" meaning "stiff", "unyielding", "not pliant or flexible", "firm", "hard". To modify Professor Slatter's words, it is the development of strength in terms of yield stress, meaning the development of solid properties. A "process of improving rigidification" is any process which improves the process of developing strength or "solidness". 115 In considering other aspects of the case it may be necessary to define other terms used in the claims. I shall address those matters as they arise.

[44]

Slatter 10 122 The primary Judge disposed of Slatter 10 at [114]-[116] as follows: 114 Dr Farrow's evidence was that Slater 10 was "a technology for enhancing settling or sedimentation, which are different from rigidification". Dr Farrow's analysis in his third affidavit sets out the basis for this conclusion, which, for the reasons Dr Farrow stated, I accept. 115 For the reasons set out earlier, I accept that the process of settling and sedimentation should be distinguished from the process of "improving rigidification" as claimed in the Patents in suit. 116 Accordingly, I conclude that the Patents in suit are novel over Slatter 10. SNF has not established the contrary proposition (explained in original). 123 Slatter 10 asserts, at column 1 ll 18-27 that: The present invention relates to a method of forming reclaimed ground using coagulative surface active agents, wherein the coagulative surface active agents are admixed with water of a sand pump containing various earth particles of assorted sizes, such as silt, clay, sand and other coarse grains, and the particles deposited to form a uniform fill. It is an object of the present invention to provide an efficient method for producing reclaimed ground having superior properties. 124 Slatter 10 then describes a process by which earth is dredged from the sea bottom or a river bed and delivered to a reclaiming area with sea or river water. At column 1 ll 31-42 it is said that: When the dredged earth includes a large amount of fine soft earth such as silt or clay, the sand and other comparatively coarse grains will be deposited near the outlet of the sand pump, and the finer silt or clay will be deposited the farther from the outlet. Thus, the production of reclaimed fill having substantially uniform properties is not accomplished. The present invention provides a method for forming reclaimed ground using coagulative surface active agents, which are admixed with the earth particles containing the delivery water, resulting in the deposition of a uniform earth fill. 125 At column 1 l 67 to column 2 l 10 the patent continues: In accordance with the present invention, a small effective amount of a coagulative surface active agent is introduced into the pipe containing the water and earth particles at a predetermined position within about 200 meters from the discharge outlet so that, after discharge from the pipe, the earth particles settle rapidly to form a reclaimed ground deposit having superior properties including a substantially uniform load bearing capacity. Whereas the deposits formed when not using the coagulative agent appear to be primarily deposits of coarse grained material such as sand, gravel etc., at one location and deposits of fine particles such as clay, silt, and the like, at another location, the deposits formed when using the coagulative surface active agent are a relatively uniform aggregated structure formed from a deposited admixture of both coarse and fine particles. 126 It is then said that: the coagulative surface active agents are to be inserted into the delivery pipe at a position which is within 200 m and, preferably, between about 20 and 50 m from the outlet; introduction of the agent too close to the outlet may mean that there is insufficient time for it to mix uniformly with the earth particles, resulting in some non-uniform deposition and inefficient utilization of such agent; alternatively, if the agent is introduced into the pipe at too great a distance from the outlet, the flocs formed by coagulation may be broken up before discharge at the outlet. 127 At column 7 ll 1-6 it is said that: In the reclaiming operation, flocs were well formed and the water near the surface became transparent. The floc formation was visible from a scaffolding board … . The water was also transparent at the spillway and hence, it can be said that any suspensions were no longer present. 128 Concerning the outcome it is said at column 7 ll 31-43 that: The reclaimed ground produced by the process of this invention is of a uniform aggregated structure and has superior characteristics. These include excellent permeability which permits rapid run-off of water, uniform and high load bearing characteristics which is evidence of effective consolidation and compressibility properties. The reclaimed land tested has exhibited these properties over long periods of time evidencing good stability. The process is advantageous in that there is little or no waste of fine particles with the overflow. It is also advantageous in that the fill settles uniformly and rapidly with quick drainage of the water permitting the land-fill operations to be carried out expeditiously. 129 Claim 4 of Patent 944 deals with the situation in which separate suspensions of fine and coarse particles are combined for the purpose of co-disposal. In Patent 944, this matter is discussed at various places. At p 7 ll 22-28, Patent 944 discloses such combination occurring at any convenient point prior to discharge at the deposition area. It also discloses addition of the polymer solution "at any convenient point, typically during transfer". At p 13 ll 4-19, Patent 944, dealing generally with the point of addition of the polymer, suggests that the polymer may be added before pumping, during pumping, or as the material exits the outlet. At p 13 ll 21-24, Patent 944 states: When aqueous suspensions of fine and coarse particulate material are being combined for the purposes of co-disposal, the effective rigidifying amount of the water-soluble polymer solution will normally be added during or after the mixing of the different waste streams into a homogenous slurry. 130 Finally, at p 16 ll 3-8, Patent 944 states: The underflow-suspension flows from the vessel, is optionally combined with additional coarse particulate material, and in which the material is then pumped to a settling area where it is allowed to dewater. The aqueous polymer solution is mixed into the material after flocculating the suspension and before the material is allowed to rigidify and dewater. 131 Notwithstanding these variations, claim 4 is limited to addition of the polymer solution "during or after" the mixing of the waste streams, but presumably "during transfer", given that claim 4 is dependent upon claim 1. 132 Ciba argues that Slatter 10 does not disclose the addition of the polymer solution during or after the mixing of different waste streams into an homogenous slurry. However this submission must be seen in light of Ciba's apparent acceptance that integer (n) is satisfied, namely that aqueous suspensions of fine and coarse particulate materials are combined for the purpose of co-disposal. Slatter 10 deals with the dredging of material from the sea bottom or a river bed for use in reclamation work. It contemplates there being a mixture of smaller and larger particles in that material. However there is no point at which any "combining" or "mixing" occurs. The material is derived from the sea bottom or river bed in a mixed state. Ciba's acceptance, that integer (n) is disclosed, suggests an assumption that the words "are combined" in integer (n) are not equivalent to the words "the mixing of the different waste streams" in integer (o). One must not lose sight of the fact that the division of claim 4 into two integers is an artificial device. The claim must be construed as a whole and, where appropriate, with regard to the specification as a whole. In Slatter 10 the coarse and fine materials are combined from the moment at which they are dredged and without any human intervention. Clearly, there is a sense in which it can be said that integer (n) is disclosed. However integer (o) requires not only "mixing" but also the existence of "different waste streams". In Slatter 10 there are no different waste streams. There is only one stream of slurry containing the dredged material. Further, it is not really a "waste stream". It is rather material acquired for a particular purpose. Claim 1, on the other hand, discloses a process for treatment of slurry containing both coarse and fine solids, regardless of how they have become mixed. 133 The question must be addressed having regard to the skilled addressee's understanding of each of the two documents. Professor Slatter considered that Slatter 10 should be read as disclosing integer (o), whilst Dr Farrow said that it was not disclosed. For present purposes, I disregard any question as to whether their evidence went to the knowledge and understanding of the skilled addressee. The primary judge did not deal with this aspect of the evidence. If, in the end, resolution of the case depends upon this question, it should be remitted for further consideration.

[45]

Slatter 12 134 As with Slatter 10, I need only consider integer (o). Slatter 12 is concerned with the treatment of phosphatic clays resulting from mining operations in the phosphate industry. The residue, after the extraction of phosphate, consists of "primary and secondary slimes and sands from processing steps" in separate streams. It is desirable that water be recovered for reuse, and that the slimes (and sand) be discarded at minimum cost. It seems that the sands and the slime are derived from different parts of the process. The following description of the invention appears at column 5 ll 31-69: It is now found that by adding a polyelectrolyte to the sands, and then mixing the sands with phosphate mine slimes, there is obtained an admixture of said sands and slimes which will compact, with the release of water to a fill material which is sufficiently strong to support men and cattle as well as mechanized farm equipment usually within a few months. It is found that if the polymer is added to a mixture of sands and slimes, the tremendous surface area of the slimes, as compared with the sands, adsorbs and hence requires an uneconomically large quantity of polyelectrolyte. Additionally the polyelectrolyte may tend to bind water and maintain fluidic characteristics which are undesirable for the present purposes. In contradistinction if the polyelectrolyte is adsorbed on the sands, it tends to bind the slimes to the surface of the sands so that the sands carry the slimes down with them and yield a mixture which in a month or longer become sufficiently rigid to support useful loads. It has been previously taught that adding the sands to the slimes of certain density will result in the sands intermingling with the slimes and carrying the slimes down to form a compact fill. The use of a polyelectrolyte greatly expands the useful operable range of solids concentration of the slimes suspension which can be compacted, and useful results can be economically obtained more readily. In the very useful range of 5% to 10% slime solids, the polyelectrolyte prevents classification of the sands, with the sands settling out first, and leaving the slimes as a residual layer above the settled sands. For best results, the sands are treated with the polyelectrolyte and added to the slimes just before the materials are deposited in the settling basin. If the suspension of sands, polyelectrolyte, and slimes is too vigorously agitated, the polyelectrolyte bonds between the sands and the slimes may be ruptured under conditions such that reconstitution does not rapidly occur and additional polyelectrolyte must be added or a larger original polyelectrolyte usage results. 135 At column 6 ll 3-13, it is said that: … but the important consideration in the present invention is the increased density of the settled materials which is now a land-fill, and stabilization to the point that the surface of the land-fill will support men, animals and equipment. A preliminary separation of some water occurs rapidly but the settling and stabilization to give a bearing surface requires considerable time often in the matter of months. Stabilization within a year or two is perfectly satisfactory and a tremendous improvement on disposal of the slimes without the sands being incorporated. 136 At column 8 ll 60-75 to column 9 ll 1-12 it is said that the process as claimed is: A process for preparing a reconstituted land-fill of bearing strength sufficient to support men, cattle and farm equipment within a period of several months which comprises: (a) just before deposition in a land-fill area, admixing waste slimes from phosphate ore processing operations, said slimes consisting essentially of an aqueous suspension of solid particles at least 99% by weight of which on a dry basis have a particle size smaller than 105 microns (- 150 mesh), said suspension having a solids content of from about 5% to about 25% by weight at the time of admixing, and, per part by weight on a dry basis of said slimes, (b) from about 0.8 to about 5 parts, by weight on a dry basis, of waste tailings, that is the sands from an ore processing operation, said tailings comprising solid particles at least 95% by weight on a dry basis of which have particle size in the range of 105 to 1000 microns (- 16 + 150 mesh), (c) said sands having added thereto, per ton of slime solids, about 0.05 to 0.5 pound of a polyacrylamide which is up to 40% hydrolyzed and has a molecular weight of at least 1,000,000, and (d) separating the water relief from said mixture, for at least one month, until the solids compact enough to possess load bearing characteristics. 137 I would have thought that Slatter 12 discloses the addition of the polymer solution to the sand, prior to its being mixed with the slimes, and that addition during or after mixing is not disclosed. However Professor Slatter said otherwise, and, Dr Farrow disagreed. This aspect of the evidence has not been resolved. If the matter is significant in the resolution of the case, it should be remitted.

[46]

Slatter 13 138 Slatter 13 is a French patent. We have two English translations. At p 1 ll 1-4 of one translation, it is said that: The present invention relates to the optimum utilization of chemical compounds which, when added in small quantities to the mixtures constituting hydraulic fills that are partially or entirely made up of what are commonly called fines, serve to improve the bearing capacity of the fill being deposited. 139 The process involves flocculation. A problem with flocculated material is that small particles are surrounded by water, causing considerable delay in release of such water and in the development of a denser structure with the required shear strength. The patent identifies a further problem, namely that particles settle at different rates, depending upon size, with the larger particles settling more quickly in the absence of a flocculant. At p 2 ll 24-28 it is said that: By substantially narrowing down the grain size distribution of the soil particles, the flocculants have the effect of causing all the particles to settle quasi-simultaneously, thereby homogenising the fill so that it contains enough sand at all points in its structure for it to immediately present an adequate bearing capacity. 140 It is then said that in the known processes the flocculant is introduced into the pipe through which the mixture is discharged, preferably between 20 and 50 metres from its orifice. It should not be introduced any closer to the orifice as it will become "practically impossible" to disperse the flocculant and ensure that it is uniformly mixed through the fines. If introduced any further from the orifice, the flocs will be "destroyed outright by the turbulence". In the known processes there is no procedure "to accelerate the draining off of the water contained in the sandy silt or sandy clay fill …". At p 3 ll 6-9 it is said that: The proposed invention will allow hydraulic fills that are potentially composed exclusively of fines to be treated with flocculants, and will allow the efficiency of that treatment to be improved while reducing the implementation requirements and accelerating the increase in bearing capacity of the fill. 141 At p 3 l 35 to p 7 l 3, it is further said that: The benefits of the improved dispersal of the flocculant and the increased efficiency of the treatment are twofold: on the one hand, they allow richer mixtures to be processed, and potentially those that are exclusively rich in fines, and on the other hand the deposited fines treated in this way are endowed with mechanical properties due to the increase in permeability such that, within just a few weeks, even in the absence of sand, the fill acquires a bearing capacity that is in the order of several tens of bars, i.e. sufficient for human beings, standard vehicles and like building structures. 142 Claim 1 is: Treatment for increasing the permeability of a hydraulic fill, characterized by the addition to the compound chemical flocculant mixture of which the fill is partially or totally composed of particles measuring less than around 50-100 microns in diameter. 143 It seems that the flocculant is to be added to material which is partially or totally composed of particles measuring less than around 50-100 microns. There is no suggestion that separate waste streams be mixed. Nonetheless Professor Slatter says otherwise, and Dr Farrow disagrees. If the dispute must be resolved in order to dispose of the case, the question should be remitted.

[48]

Slatter 3 145 Slatter 3 deals with "the treatment of mineral material, especially waste from the Bayer alumina process, including the treatment of red mud wastes in order to render it more easily disposable". In the third paragraph on p 1 it is said that: In some cases the waste material such as mine tailings can be conveniently disposed of in a mine to form a backfill. Generally backfill waste comprises a high proportion of coarse large sized particles together with other smaller sized particles and is pumped into the mine [as a] slurry where it is allowed to dewater leaving the sedimented solids in place. It is common practice to use flocculants to assist this flocculation process. 146 The patent identifies the need to load multiple layers of waste in stacks and refers to the difficulties, identified in Patent 944, in ensuring that it flows over the surface of previously rigidified waste, within acceptable boundaries, and is allowed to rigidify to form such stacks. Those stacks may be used to support multiple layers of rigidified material without the risk of collapse or slip. There is then reference to the Bayer process and to some of the prior art also mentioned in Patent 944. 147 At the third and fourth paragraphs on p 3 it is said that: A process according to the present invention provides 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 polymer which has an intrinsic viscosity of at least 3 dl/g. The addition of the polymeric particles, comprising water soluble polymer to the material enables the material to retain its fluidity and to be easily pumped but upon standing forms a solid mass that is strong enough to support layers of subsequent rigidified material. We have surprisingly found that the presence of water soluble polymers applied in the form of particles actually enables the material to remain fluid and pumpable during the pumping stage but results in rapid loss of fluidity and rigidification on standing. Furthermore this treatment desirably results in aqueous liquid being released from the material on standing. 148 At para 4 on p 6, Slatter 3 continues: In the invention the water soluble polymer may be formed by any suitable polymerisation process. The polymers may be prepared for instance as gel polymers by solution polymerisation, water-in-oil suspension polymerisation or by water-in-oil emulsion polymerisation. 149 At para 3 on p 7 it is said that: Alternatively the water soluble polymer particles may be provided as a dispersion in an aqueous medium. 150 In the last paragraph on p 14 and on p 15 it is said that: It is surprising that the process according to the invention forms a product which rigidifies far better than alternative treatments, for instance the use of water swellable, water swellable polymers or pre-formed solutions of water soluble polymers. It is surprising that especially good results are obtained by employing solid grade particulate polymers, comprising solid grade polymer, comprising individual large size polymer particles as described herein. 151 In the second paragraph on p 15 it is said that: One advantage of additions in powder form is that the viscosity does not increase or diminish as rapidly as a solution-based addition. 152 The primary Judge accepted Dr Farrow's evidence that the addition of the polymer as an aqueous solution was an essential element of claim 1. Dr Farrow accepted that water-soluble polymer might be added to mineral tailings, other than in solution, but said that in such cases, the polymer would act in a different manner, and have different effects compared to its use in solution. 153 At [96] her Honour concluded that Slatter 3 "recommends against the addition of polymer in aqueous solution and in favour of the use of polymeric particles" and continued: Consistently with this, Slatter 3 distinguishes between aqueous solutions, emulsions and dispersions. Slatter 3 expressly describes its own teaching (the use of polymer in the form of particles, whether solid, in dispersion or an emulsion) as "far better" than alternatives such as "pre-formed solutions of water soluble polymers". 154 Her Honour then observed that Dr Slatter had conceded that: … first, Slatter 3 does not teach the administration of aqueous solution of polymer; second, Slatter 3 teaches that adding the polymer either as a particulate dispersion or as an emulsion gives a far better result than using an aqueous solution; third, where particulate matter is present in an aqueous medium, it is not dissolved; and, finally, there is "no doubt" that Slatter 3 is particularly looking at adding the polymer to the slurry in a particle form. 155 Use of language such as "distinguishes between", "recommends against" "describes its own teaching" and the word "teaching" raises questions concerning the precise requirement of the Patents Act 1990 (Cth) (the "Patents Act") as to novelty. Resolution of these questions involves consideration of s 7 of the Patents Act in conjunction with the definitions of the terms "prior art base" and "prior art information" contained in the statutory dictionary. It appears to be common ground that Slatter 3 is an article of prior art information and that it was, at the relevant time, part of the relevant prior art base for the purpose of determining, pursuant to s 18, whether the claimed invention was novel. Section 7(1) provides: For the purposes of this Act, an invention is to be taken to be novel when compared with the prior art base unless it is not novel in the light of any one of the following kinds of information, each of which must be considered separately: (a) prior art information (other than mentioned in paragraph (c) made publicly available in a single document or through doing a single act … . 156 The requirement is that the invention be novel when compared with an appropriate prior art document. Thus a question arises as to whether an earlier disclosure anticipates a claim in a later patent if, in the document containing the earlier disclosure, another process or product is said to be better in achieving a particular purpose. I turn to the cases. The starting point is the decision of the English Court of Appeal in General Tire & Rubber Company v Firestone Tyre and Rubber Company Ltd (1971) 1A IPR 121, especially at 137-138 where Sacks LJ said: The word "anticipation" is not used in the text of the Patents Act 1949, although it appears in the side notes to ss 7 and 8 of the Act. The language of s 32(1)(e), with which we are concerned in this aspect of the case, is as follows: That the invention, so far as claimed in any claim of the complete specification, is not new having regard to what was known or used, before the priority date of the claim, in the United Kingdom. Stated in the shortest terms, the problem is to determine whether the device, to use a neutral expression, has been forestalled in this country. For the sake of clarity we will refer to the patentee or would-be patentee of the device which is alleged to have been anticipated as the "patentee" and to the inventor of the device which is alleged to constitute anticipation as the "prior inventor". In the present case we are not concerned with anticipation by earlier use of the patentee's device but with anticipation by prior publication: that is to say, it is contended that the plaintiffs' invention as claimed in their patent was at the priority date of their claim something which was known in the United Kingdom by reason of prior publication. To determine whether a patentee's claim has been anticipated by an earlier publication it is necessary to compare the earlier publication with the patentee's claim. The earlier publication must, for this purpose, be interpreted as at the date of its publication, having regard to the relevant surrounding circumstances which then existed, and without regard to subsequent events. The patentee's claim must similarly be construed as at its own date of publication having regard to the relevant surrounding circumstances then existing. If the earlier publication, so construed, discloses the same device as the device which the patentee by his claim, so construed, asserts that he has invented, the patentee's claim has been anticipated, but not otherwise. In such circumstances the patentee is not the true and first inventor of the device and the claimed invention is not new in the terms of s 32(1)(e). The earlier publication and the patentee's claim must each be construed as they would be at the relevant respective dates by a reader skilled in the art to which they relate having regard to the state of knowledge of such art at the relevant date. The construction of these documents is a function of the court, being a matter of law, but since documents of this nature are almost certain to contain technical material, the court must, by evidence, be put in the position of a person of the kind to whom the document is addressed, that is to say, a person skilled in the relevant art at the relevant date. … When the prior inventor's publication and the patentee's claim have respectively been construed by the court in the light of all properly admissible evidence as to technical matters, the meaning of words and expressions used in the art and so forth, the question whether the patentee's claim is new for the purposes of s 32(1)(e) falls to be decided as a question of fact. If the prior inventor's publication contains a clear description of, or clear instructions to do or make, something that would infringe the patentee's claim if carried out after the grant of the patentee's patent, the patentee's claim will have been shown to lack the necessary novelty, that is to say, it will have been anticipated. The prior inventor, however, and the patentee may have approached the same device from different starting points and may for this reason, or it may be for other reasons, have so described their devices that it cannot be immediately discerned from a reading of the language which they have respectively used that they have discovered in truth the same device; but if carrying out the directions contained in the prior inventor's publication will inevitably result in something being made or done which, if the patentee's patent were valid, would constitute an infringement of the patentee's claim, this circumstance demonstrates that the patentee's claim has in fact been anticipated. If, on the other hand, the prior publication contains a direction which is capable of being carried out in a manner which would infringe the patentee's claim, but would be at least as likely to be carried out in a way which would not do so, the patentee's claim will not have been anticipated, although it may fail on the ground of obviousness. To anticipate the patentee's claim the prior publication must contain clear and unmistakable directions to do what the patentee claims to have invented: ….. A signpost, however clear, upon the road to the patentee's invention will not suffice. The prior inventor must be clearly shown to have planted his flag at the precise destination before the patentee. 157 In this passage anticipation is variously said to arise because the invention was "known", or the "device" was "disclosed", or it was "described", or there were "instructions to do or make" something which would infringe the patentee's claim. 158 In Nicaro Holdings Pty Ltd v Martin Engineering Co (1990) 91 ALR 513 at 517, Lockhart J expressed the test for anticipation in this way: It is well established that the prior art must disclose all features of the invention embodied in the patent in suit and must do so in clear, unequivocal and unmistakable terms. The prior art must enable the notional skilled addressee at once to perceive and understand and be able practically to apply the discovery without the necessity of making further experiments. Whatever is essential to the invention must be read out of or gleaned from the prior publication … . 159 At 530 Gummow J (Jenkinson J concurring) cited the following passage from the speech by Lord Reid in Van der Lely NV v Bamfords Ltd (supra) at 71-72: The law regarding anticipation derives from Lord Westbury's statement of it in Hill v Evans … . There are two branches of this statement. The first is that "a person of ordinary knowledge of the subject would at once perceive and understand and be able practically to apply the discovery without the necessity of making further experiments". The appellants maintain that even if the skilled man could perceive in the photograph all the integers in claim 1 he could not apply the discovery without making further experiments. But Lord Westbury must have meant experiments with a view to discovering something not disclosed. He cannot have meant to refer to the ordinary methods of trial and error which involve no inventive step and are generally necessary in applying any discovery to produce a practical result. … The other requirements is that "the information given by the prior publication must for the purposes of practical utility be equal to that given by the subsequent patent". There may be cases where the skilled man has to have the language of the prior publication translated for him or where he must get from a scientist the meaning of technical terms or ideas with which he is not familiar, but once he has got this he must be able to make the machine from what is disclosed by the prior publication … . 160 After reference to other authorities Gummow J observed at 531: It follows from the English authorities as they have been applied in Australia that, whilst Hill v Evans does not require a literal disclosure and something less may suffice, and whilst an alleged paper anticipation is to be treated as read by a skilled addressee, a disclosure will fall short of an anticipation by description of an effective means by which the combination claimed in the patent in suit might be produced, if what is required of the skilled addressee is the exercise of any inventive ingenuity and the taking of any inventive step. 161 In Bristol-Myers Squibb Co v FH Faulding & Co Ltd (2000) 97 FCR 524 at 546-547, Black CJ and Lehane J set out the following passage from the judgment of Lord Westbury in Hill v Evans (1862) 4De & GFJ 258; 45 ER 1195 at (300; 1199): The question then is, what must be the nature of the antecedent statement? I apprehend that the principle is correctly thus expressed: - the antecedent statement must be such that a person of ordinary knowledge of the subject would at once perceive, understand, and be able practically to apply the discovery without the necessity of making further experiments and gaining further information before the invention can be made useful. If something remains to be ascertained which is necessary for the useful application of the discovery, that affords sufficient room for another valid patent. And (at 301, 302;1199-1200): The invention must be shewn to have been before made known. Whatever, therefore, is essential to the invention must be read out of the prior publication. If specific details are necessary for the practical working and real utility of the alleged invention, they must be found substantially in the prior publication. Apparent generality, or a proposition not true to its full extent, will not prejudice a subsequent statement which is limited and accurate, and gives a specific rule of practical application. The reason is manifest, because much further information, and therefore much further discovery, are required before the real truth can be extricated and embodied in a form to serve the use of mankind. It is the difference between the ore and the refined and pure metal which is extracted from it. Again, it is not, in my opinion, true in these cases to say, that knowledge, and the means of obtaining knowledge, are the same. There is a great difference between them. To carry me to the place at which I wish to arrive is very different from merely putting me on the road that leads to it. There may be a latent truth in the words of a former writer, not known even to the writer himself; and it would be unreasonable to say that there is no merit in discovering and unfolding it to the world. Upon principle, therefore, I conclude that the prior knowledge of an invention to avoid a patent must be knowledge equal to that required to be given by a specification, namely, such knowledge as will enable the public to perceive the very discovery, and to carry the invention into practical use. 162 Their Honours then referred to the decision of Parker J in Flour Oxidizing Co Ltd v Carr & Co Ltd (1908) 25 RPC 428. That case concerned a patent for using an apparatus previously disclosed as suitable for a different use. His Lordship said (at 457): But where the question is solely a question of prior publication, it is not, in my opinion, enough to prove that an apparatus described in an earlier Specification could have been used to produce this or that result. It must also be shown that the Specification contains clear and unmistakable directions so to use it. 163 After considering other authorities Black CJ and Lehane J continued at 548: What all those authorities contemplate, in our view, is that a prior publication, if it is to destroy novelty, must give a direction or make a recommendation or suggestion which will result, if the skilled reader follows it, in the claimed invention. A direction, recommendation or suggestion may often, of course, be implicit in what is described and commonly the only question may be whether the publication describes with sufficient clarity the claimed invention or, in the case of a combination, each integer of it. (emphasis added) But in this case medical practitioners hardly needed to be told that it was possible to infuse a particular dose of Taxol over three hours, or how to do it. Nor, equally obviously, is that the point of the claims … . 164 In that case, the claimed invention was a process of administering a drug (Taxol), in the treatment of cancer. The relevant prior art documents were reports of clinical trials. Their Honours concluded that although the prior art disclosed the treatment of cancer, using Taxol, and although the process of administration, the subject of the patent, was actually disclosed, problems of toxicity and hypersensitivity were also identified. In effect, the various items of prior art demonstrated that there had been trials, identifying positive outcomes, but with complications and/or that further work was necessary before the drug could be used for clinical purposes. In that sense the prior art documents did not recommend the use of the drug, either in accordance with the regime identified in the patent or otherwise. 165 In H Lundbeck A/S v Alphapharm Pty Ltd (2009) 177 FCR 151, Emmett J said at [69]: If the prior art information discloses information that enables the so-called invention to be performed, the so-called invention will not be novel. Whether prior art information does so will depend upon the claims made in respect of the so-called invention. Thus, it is necessary to identify the so-called invention, so far as claimed in a particular claim. Once the so-called invention has been properly identified, it is a question of whether the prior art information discloses sufficient information to enable the relevant skilled addressee, at or before the priority date for the claim of the so-called invention, to perform the invention. 166 At [178] et seq, Bennett J said: 178 Care must be taken to distinguish between the tests for novelty and want of inventive step, in particular when looking to see what the prior art "teaches". The concept of novelty in Australia involves a comparison between the invention as claimed in the claims of the patent and prior art information. Often, this must be determined by looking to prior publications which are to be read by the skilled addressee to determine what they disclose. Generally speaking, the consideration of what a prior publication "teaches", especially when one talks of "teaching away" from the claimed invention, tends to be relevant to questions of obviousness not inventive step. 179 As Lord Hoffmann said …, an invention is a piece of information and making matter available to the public therefore requires the communication of information. Whether or not such information has been communicated depends on the subject matter of the claim and the extent of the prior disclosure to the skilled addressee. 180 Where the prior publication discloses exactly what is claimed, there is anticipation. This can be objectively determined and, apart from an understanding of terms of art, the evidence of the skilled addressee is not likely to be of much further assistance. However, this does not always occur and many of the authorities contain discussions of the extent to which a disclosure less than the entirety of the claim constitutes an anticipation of a product or a process to deprive the claimed invention of novelty. 181 If the prior art discloses some but not all integers of a claimed patent to a product, such as a combination, there is anticipation if the skilled addressee would add the missing information as a matter of course and without the application of inventive ingenuity or undue experimentation … . 182 It may be that the prior disclosure is of a method that produces the claimed product. If that method leads inexorably to the product, there is anticipation … . If it may or may not result in the claimed product, there is no anticipation. 183 It is these last two examples that, in Australia, could be said to be within a shorthand description of "enabling disclosure". That is, the disclosure is not complete but it is sufficient to enable the skilled addressee, in the ordinary course and without invention, to add what is missing in the prior publication to obtain the claimed invention … . 167 At [190] her Honour continued: It follows that, where the prior publication is of the subsequently claimed invention, that is sufficient. Where the prior disclosure falls short of a complete disclosure, the question of the sufficiency of that disclosure arises. It is there that consideration must be given to the quality of a disclosure to the skilled addressee armed with common general knowledge. It is in that context that, in a limited fashion, questions of "enablement" can be said to arise. The use of that expression tends to cause confusion between anticipation and sufficiency. Rather, the Court, armed with the evidence of the skilled addressee as to terms of art and the nature and extent of the disclosure in the prior art document, must determine whether the prior disclosure is sufficient to enable the skilled addressee to perceive, understand and, where appropriate, apply the prior disclosure necessarily to obtain the invention. 168 Concern over the use of the word "teach" in connection with novelty is, I suspect, founded upon a fear that it may tend to emphasize recommendation rather than disclosure. As Black CJ and Lehane J said in Bristol-Myers, an anticipating direction, recommendation or suggestion may be implicit in a description or disclosure. Where, as in that case, the disclosure was accompanied by a description of negative aspects of the trials, it was difficult to construe the document as a "direction, recommendation or suggestion". Further, some cases use other words to describe the necessary essence of a disclosure. The word "disclosure" is, itself, commonly used. Whilst the Bristol-Myers disclosure was not sufficient to constitute anticipation, this was because of the negative aspects, disclosed by the clinical trials. 169 In the end, the question is whether Slatter 3 discloses the use of a polymer solution as part of the process of improving rigidification given that, save for integer (o), all other integers of the claimed invention are disclosed. In my view the passage on p 14, commencing with the words "It is surprising" involves a comparison of the performance of the invention using polymers in particulate form and in solution. As I have said, Slatter 3 discloses that the use of particulate polymers "forms a product which rigidifies far better than the alternative treatments", and that the "process of the invention more effectively minimizes the area taken up by the stack of the material of given volume" whilst "maintaining the pumpability of the material." There is no suggestion that use of a polymer solution will not work. Slatter 3 rather implies that a polymer solution will work, but not as well as if it be used in particulate form. Thus it discloses use of a polymer solution in the process claimed. The difference in performance may be attributable to the fact that use in particulate form will not produce any increase or diminution in viscosity. In any event, integer (e) is disclosed as part of the process described in Slatter 3. 170 Slatter 3 does not describe the method for preparing a solution of the aqueous polymer. That matter is dealt with in some detail in Patent 944. I do not understand Ciba to rely upon the absence of such instructions. No doubt the mechanics of performing that function would be well known to a person skilled in the relevant art. 171 I should add that Professor Slatter saw anticipation of integer (e) in other aspects of Slatter 3. However, on appeal, SNF does not rely on that aspect of his evidence. 172 I turn to integer (o). I have previously discussed it in connection with Slatter 10, Slatter 12 and Slatter 13, concluding that the question depends upon resolution of the conflict between the evidence of Professor Slatter and that of Dr Farrow. The same problem arises in connection with Slatter 3. Dr Slatter read Slatter 3 as disclosing the mixture of fine and coarse particles, and that the polymer solution should be added during or after combination. SNF submits that this evidence was unchallenged and, perhaps, supported by Dr Farrow's evidence that in the Bayer process, some plants separate the fines from the sand, whilst others transfer the material in combined form. However Ciba points out that in his written evidence Dr Farrow disputed the assertion that Slatter 3 disclosed integer (o). If it be necessary that the conflict be resolved in order to decide the case, the question should be remitted.

[49]

Slatter 4 173 This patent concerns processes by which mineral slurries are treated for more efficient, cost-effective disposition. Specifically, it relates to the tailings generated from the Bayer process and methods for stacking such tailings. Slatter 4 refers generally to existing processes using tailings dams and asserts at p 2 ll 12-15: Water-soluble polymeric emulsions have been used as flocculants, generally in the form of inverted dilute solutions, in dewatering applications for solid liquid separations. Though dewatering can be effective, it can be expensive to conduct and may not be practical or efficient for treating large volumes of material. 174 The patent continues at p 2 ll 21-28: A method of treating red mud is disclosed in European Patent Application EP 388108. In that patent application, red mud from a Bayer process is blended with particles of water absorbent, water-insoluble polymer and the mixture is allowed to stand and rigidify. The process disclosed is believed by the patentee to be particularly suitable for treating materials having dispersed particulate solids of very small particle size, though generally aqueous liquids of dispersed particulate solids are also disclosed. The water-insoluble polymers may be added in the form of bonded aggregates or a dispersion in water immiscible liquid. 175 The patent then discloses that a water-soluble polymer, in the form of an inverse (water in oil) emulsion, can be used to stabilize slurries of particulate solids in order to modify their characteristics so as to render them stackable, thereby maximizing the use of waste storage space. It is said at p 2 l 34 - p 3 l 3 that: Moreover, the stabilizing effectiveness of the water-soluble polymers is surprisingly enhanced when they are used in their inverse emulsion form, rather than first being inverted to form a dilute aqueous solution, as such polymers are typically used in the art. See, for example US Patent No 4,767,540. 176 Other evidence suggests that the effect of inverting an emulsion to form a dilute aqueous solution has the effect that the relevant polymer particles are dissolved in water. If so, then the addition of an inverted emulsion will involve the addition of a solution of a water-soluble polymer in water. I shall return to this matter at a later stage. 177 At p 4 ll 14-20 it is said that: Typical slurries that are stabilized according to the instant invention include but are not limited to aqueous dispersions, preferably tailings or mineral slurries obtained from a platinum ore body, a body of coal, a copper ore body, a tar sand body, an ore-body from a diamond mine, phosphate and gold slimes. Aqueous slurries of particulate solids that comprise a clay are also contemplated. A process for stacking aqueous [slurrys] comprising particulate solids, either organic or inorganic, is also contemplated by the instant invention. 178 Slatter 4 discloses the results of tests using polymers in various forms, including two tests in which a dilute solution was used. Both produced less satisfactory results than those in which emulsions were used. At trial the only question concerning Slatter 4 was whether integers (e) and (o) were disclosed. Professor Slatter considered that the reference in Slatter 4 to the previously known use of inverted dilute polymer solutions derived from polymer emulsions anticipated integer (e). As with Slatter 3, he also saw other aspects in which Slatter 4 anticipated that integer. As with Slatter 3 SNF has not, on appeal, relied on that evidence. 179 According to the primary Judge at [105]-[106]: 105. In Dr Farrow's opinion, the key difference between Slatter 4 and Patent 944 was that Slatter 4 involved the use of a water-soluble polymer in a form of water-in-oil emulsion. As he said: This means that the water soluble polymer is not in solution, rather it is trapped within very small water droplets within a continuous oil phase. As a result, in his opinion, integer (e) was absent. 106. Dr Farrow explained the difference: With a aqueous solution of a water soluble polymer the molecules are separated and solvated (ie, surrounded by water molecules) and will have an elongated confirmation which enhances their ability to co-absorb on two or more particles to induce flocculation. With a water and oil emulsion, the flocculant molecules are "trapped" in a concentrated form within small water droplets distributed throughout an oil phase. "Activation" of a water in oil flocculant requires high shear mixing such as that induced by a centrifugal pump, as described in Slatter 4 on page 10, lines 24-31. Consequently the properties of the flocculant molecules in an aqueous solution are very different to those in a water-in-oil form. In fact, the examples set out on pages 11-13 in Table 1 on page 14 of Slatter 4 suggests that use of an aqueous or dilute solution of polymer would not achieve the intended outcome of the process. 180 Concerning Professor Slatter's evidence her Honour said at [101]-[102]: 101. SNF argued, first, that Slatter 4 disclosed the use of polymers in aqueous solutions, referring in particular to the statements that: Water-soluble polymeric emulsions have been used as flocculants, generally in the form of inverted dilute solutions, in dewatering applications for solid liquids separations. Moreover, the stabilising effectiveness of the water-soluble polymers is surprisingly enhanced when they are used in their inverted emulsion form, rather than first being inverted to form a dilute aqueous solution, as such polymers are typically used in the art. See, for example, US Patent no 4, 767,540) (pp 2-3). 102. SNF contended that the significance of these passages lay in their disclosure of the use of water-soluble polymers in solution following inversion (or "flipping") from their emulsified form. The evidence at trial established that it was commonly accepted by persons skilled in the field of mining waste disposal (such as Messrs Schroeter, Coleman and Bannister [sic]) that, in the present context, before an emulsion becomes effective, it must be flipped, that is, dissolved in solution. SNF submitted that the cited passages reflected a common practice with respect to the use of water-soluble polymers, and constituted comments on the effectiveness of the emulsion form as compared with the aqueous form in achieving the object of the invention - the stacking of particular solids in an aqueous liquid. According to SNF, Slatter 4 did not contain a teaching away, as alleged by the Ciba respondents. 181 The evidence of the witnesses Schroeter, Coleman and Banister is of some importance. At ts 173 ll 1-19, in the cross-examination of Mr Schroeter, the following passage appears: And it is true to say that the solid form is a powder which would ordinarily be made into a solution, perhaps very close to the time it is used?---It would normally be a granular solid, yes - perhaps not a powder, a granular solid. A granular solid?---And it would normally be prepared as an aqueous solution prior to use. Could be prepared as a particulate or dispersion?---It could be. There are methods for preparing it as a particulate dispersion but it would be very unusual to see that in practice. Right. And the emulsion would ordinarily be a reverse phase emulsion?---Yes. Yes. And the emulsion could either be applied as an emulsion or it could be flipped, could it not, into a solution?---Again, normal practice would have it flipped and turned into a solution prior to application but on occasion the customer requirements or conditions are such that you don't have the right equipment or water or whatever it is that you need, then on very rare occasions, applied as the neat emulsion. 182 Similarly in Mr Coleman's cross-examination at ts 219 l 42 to ts 220 l 13, the following passage appears: You said that the Alfloc 625 was an emulsion product. In what way was that applied? Was it applied as an emulsion?---No, as - it's purchased as an emulsion and then it's diluted to a water soluble product. The active components are water soluble so that, effectively, you have a solution that you will then use to apply. Was the emulsion flipped?---That's correct. During the dissolution you flip the emulsion. It's an aqueous phase little droplets with the active ingredient in it in a continual oil phase as purchased. Then you flip it so that what you're left is with little droplets of oil, and the continuous phase is the solution containing the polymer. Yes, right. So that the product that you acquired was not, in this case, in its raw state applied? In other words, it wasn't applied - - -?---That's correct, but no - - - - - - as an emulsion?--- - - no product would be. Well, her Honour can deal with other evidence in relation to that, but what you're saying is that the Alfloc 625 was not applied in the way in which it was received; it was flipped and in solution, it was applied?---That's correct. 183 Finally in Mr Banister's cross-examination at ts 241 l 34 to ts 242 l 7 the following passage appears: … So a soluble polymer which, in the solution - it might have a particular salt concentration that rendered the polymer, in that solution, insoluble so it was to be in a particulate form. Would you regard that as different to finding the polymer in an aqueous solution?---Your description of that is outside of my experience of it, right? Now, I would say that again, in my experience, the materials that have been presented to me over the years and I have used, right, have always been totally dissolved so that they are in a liquid state, be it an emulsion of whatever concentration. Yes. So when you refer to an aqueous solution, you refer to a polymer that is fully dissolved?---Correct. And if you are referring to an emulsion that has been administered, you would be referring to the emulsion that has been flipped?---It has been an emulsion. It will be in a liquid form, right, and whatever solids were in there at - prior to conversion from a solid has water added to it at some stage of the production process, and then that - so that there is no more solids that can be seen in solution. Yes. And if it in an emulsion that we are talking about, that has to be turned into a solution by high shearing forces. Is that generally correct?---Not necessarily, but that is one of the methods. 184 At paras 38 and 39 of its written submissions Ciba asserts: 38. At trial Professor Slatter contended that the disclosure of the addition of polymer in emulsion was the disclosure of polymer in aqueous solution. The aqueous phase of an emulsion is not an aqueous solution and the appellant now appears to accept this. Examples 3 and 5 in Slatter 4 use polymer in aqueous solution for slump tests but these examples are unsuccessful. Thus Slatter 4 tells the reader to avoid using aqueous solutions but rather to use emulsions. 39. Having been taken through Slatter 4, Professor Slatter conceded under cross examination that: (a) the document suggests that one does not combine an emulsion that has been inverted into a solution but rather one should combine the emulsion in its emulsion form; (b) the emulsion is "physically different" to the solution form; (c) there will be a delay in the activation of the polymer if it is added as emulsion rather than solution; and (d) he was not in a position to disagree with Dr Farrow that the properties of flocculant molecules in an aqueous solution are very different to those in a water-in-oil form. 185 The parties seem not to have engaged on this issue, or at least they did not do so at the trial. Professor Slatter is, fairly clearly, speaking about disclosure of the use of an aqueous polymer solution derived from an emulsion. His evidence, in conjunction with that of Messrs Schroeter, Coleman and Banister, particularly that of Mr Coleman, demonstrates that following inversion, one is left with "little droplets of oil, and the "continuous phase" which is an aqueous solution containing the polymer. In the course of argument it was explained to us that the "continuous phase" is the material in which another substance is dissolved, in the case of an aqueous solution, water. Thus Mr Coleman said that following the flipping of the emulsion, instead of having the polymer contained in small particles of water within the continuous phase, namely oil, as described by Dr Farrow, one has water in which the polymer is dissolved and, separately, small drops of oil. It is relatively clear that the passage from Dr Farrow's evidence to which her Honour refers at [105] and [106] is not dealing with that situation. When this distinction is understood, the various statements said to have been conceded by Professor Slatter in cross-examination are really quite irrelevant. It has not been suggested that the evidence of Messrs Schroeter, Coleman and Banister was challenged in any way in this regard, or that there was evidence to the contrary concerning the state of an inverted emulsion. 186 If I were to decide this matter, upon the material to which we have been referred, I would be inclined to conclude that, as a matter of logic, and based upon the evidence of Messrs Schroeter, Coleman and Banister, particularly that of Mr Coleman, following inversion of an emulsion, the polymer is contained in an aqueous solution and that Slatter 4 anticipates that aspect of the claimed invention. As with Slatter 3 Ciba submits that it was not so disclosed, primarily because it was not recommended by Slatter 4. Slatter 4 disclosed that experiments using aqueous solutions were found to be unsuccessful. It is also submitted, as it is with respect to Slatter 3, that its use, as part of the process otherwise disclosed by Patent 944, is not disclosed in Slatter 4. 187 Slatter 4 certainly discloses the use of unflipped emulsions. This appears particularly at p 2, ll 10-20 and p 2, l 29 to p 3 l 3. However the disclosure of the historical use of flipped emulsions cannot be read as disclosing use in the process otherwise described. Further, as a result of testing, it is said that "emulsion polymers significantly reduce their stabilising effectiveness if the emulsion is inverted prior to use on the dispersion of mineral solids." Although I consider that Slatter 4 discloses use of an aqueous polymer solution (produced by inversion of a polymer emulsion), it suggests that such use will not be successful if used in the claimed process in place of the uninverted emulsion. I therefore conclude that Slatter 4 does not anticipate the claimed invention. 188 Professor Slatter and Dr Farrow again disagree as to integer (o). However, in view of my conclusion as to integer (e), it is not necessary that the question be remitted.

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Londonderry 190 The primary Judge accepted evidence from Peter James Woolley that he tested and implemented a "super-flocculation" process at Londonderry, and that polymers were used in the process of treating mineral sands there from about 1981 until at least 1989. The process involved adding flocculant in solution to slurry, after the slurry had passed through a hydrocyclone which removed coarser particles. The flocculant was added at a minimum of two points during the transfer of the slurry to the deposition area. The process "caused the solids in the tailings to separate very rapidly from the water and as a result solids stacked up at the end of the pipe which deposited the tailings in the deposition area". Mr Woolley said that the pipe had to be regularly moved to avoid the stacks becoming too high. Three photographs taken by Mr Woolley in 1981 demonstrate this effect. In cross-examination he said that the effect of the super flocculation process was to speed up "dramatically" the time in which the deposits in the deposition area could be reworked, that is, walked upon, dug out, reafforested or revegetated. Without this process the deposits were like quicksand and would take months to dry out. 191 Mr Coleman also gave evidence concerning the Londonderry process. He said that in 1984, polymers were used there to treat tailings. Her Honour accepted his evidence as to the clarity of water released and the formation of stacks compacted in a homogeneous mass which could be walked upon within six weeks. This evidence confirmed that of Mr Woolley. Mr Coleman gave evidence that cracks in the deposits were 12 feet deep, suggesting stacking, and that the material appeared, to the naked eye, to be very largely homogeneous. In his affidavit, Mr Coleman described the process as involving the addition of flocculants to the tailings stream in a number of locations, whilst the stream travelled through the transfer pipe to the dam. He said that in order to recover further water, flocculant was also added to the waste slurry stream as it entered the tailings dam. This caused the formation of stacks. He said that even after the disposal of rigidified tailings in one dam was discontinued, and another commissioned, stacks in the first dam continued to dewater, allowing further water to be recovered for reuse. The dewatered stacks would dry out rapidly over several weeks and could then be loaded on to trucks and relocated. The water which ran off was of very high quality, sometimes of drinking quality. 192 The photographs taken by Mr Woolley seem strongly to support his description of the outcome of the process and the description given by Mr Coleman. I should also say that they look very similar to the so-called stacks which appear in a video recording of the process at Bulga (made in 2006) and are said to show the SNF process. That process is said to be, effectively, an embodiment of the claimed invention. The evidence that the Londonderry stacks were capable of being walked upon shortly after their formation, appeared to the naked eye to be of relatively consistent homogeneity and continued to dry out, yielding further water with the passage of time, is important. These characteristics are said to be distinctive of the product of the claimed invention. As I have said, her Honour accepted the evidence of both Mr Woolley and Mr Coleman. At [145] her Honour identified the real point at issue between the parties with regard to the Londonderry process as being "whether the deposition of flocculated fine particle slurries in the deposition area was to be characterized as settling/sedimentation or rigidification". 193 Professor Slatter said that Mr Woolley's statement, that super-flocculation led to the formation of floccs and subsequent settling, led him to conclude that there was rigidification because this process "must always result in rigidification". He considered that rigidification and dewatering were clearly described by Mr Woolley when he said that, "Once the flocculants had been added the tailings almost immediately separated into large floccs of solids and clear water". Her Honour said, at [146], that SNF relied again upon the proposition that there was no material difference between the process of settling/sedimentation and the process of rigidification, and that this proposition was "assumed in Professor Slatter's conclusion that all elements of the claims of the patent (in this case, Patent 834) were present". 194 At [148] her Honour set out the following statement by Dr Farrow: I note the process described by Mr Woolley in para 16(a), which he called Super Flocculation, "causes the solids in the tailings to form large floccs and rapidly settle". I do not consider that this discloses or describes a process of rigidification … In paragraph 24, Mr Woolley makes a statement relating to the solids rapidly forming stacks in the deposition area. The supplied photos do not show any evidence of the formation of a stacked deposit with any real structure or strength or homogenous distribution. It appears to me that what is occurring is really sub-surface settlement or sedimentation. Therefore, at least elements (a), (b) and (c) of claim 1 are not present. 195 Although the primary Judge accepted the evidence of Messrs Woolley and Coleman concerning the Londonderry process, such evidence was dismissed as an example of anticipating prior art. In so doing her Honour was influenced by Dr Farrow's assertion that Mr Woolley's account did not describe a process of rigidification. For reasons which I have given, Dr Farrow's definition of that term does not reflect its meaning in the Patents. Mr Woolley said that the process produced stacking. Her Honour accepted that evidence. Dr Farrow said that he could not identify stacking in Mr Woolley's photographs. Curiously, in its written submissions on appeal, at para 47, Ciba submits that although SNF relies on the evidence from Messrs Woolley and Coleman that stacks formed, such formation did not "establish anticipation" apparently because Patent 944 discloses that the existence of stacking was disclosed in the prior art (at p 1 ll 26 and 32). Such an approach seems to be inconsistent with any assertion that the distinction between a process of settlement and sedimentation and a process of rigidification is the forming of stacks. Further, if Ciba's submission is correct, one wonders why so much time was spent on the question of stacking, both at trial and on appeal. 196 It is unclear to me how her Honour reconciled her acceptance of the evidence of Mr Woolley and Mr Coleman with her acceptance of Dr Farrow's view that Mr Woolley's photographs did not show stacking. It may be that the absence of any clear definition of "stacking" has caused the problem. Although there are other unsatisfactory aspects to this part of the case, her Honour's decision was so dominated by the perceived distinction between settlement and sedimentation, on the one hand, and rigidification on the other, that the relevant findings should be set aside and the question remitted for further consideration, unless the case is disposed of on some other basis. I should add that Ciba did not seek to support her Honour's finding on any basis other than her finding as to such distinction.

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Bulga 197 I have previously referred to use of the SNF process at Bulga. It is shown in the video recording. However, relevant to the question of novelty is a different process, used there in 2002. Mr Banister said that in 2002 the mine operators were encountering problems with the poor quality of water being recovered from the deposition area. He devised a method, which he called "secondary flocculation", to address the problem. The primary Judge set out his evidence as follows at [153]: This process involved pumping the ultra-fines forming at the top of the first [pit] through a pumping and flocculating station from the first (dirty) to the second [empty] [pit]. This additional flocculant aided in separating out the ultra fines material pumped from the first [pit]. The second [pit] did not have a flat graded floor. … As a result the second [pit] actually housed a number of smaller depressions which acted as large settling ponds. The slurry which was pumped into the second [pit], having been treated with flocculant a second time, settled in these ponds allowing the solids to settle and the water to be clarified. [T]he product used for the secondary flocculation was a Nalco flocculating product which was a water soluble polymer. Liquid flocculant was injected into the slurry as it was pumped from the first [pit] to the second [pit]. … The flocculant was added as an aqueous solution to the slurry. 198 Her Honour accepted Mr Banister's evidence, noting that Ciba's cross-examination of him was designed to establish that "the result was not rigidification within the Patents in suit". Predictably, Professor Slatter asserted that Mr Banister's evidence disclosed all integers of the claims in Patent 944, again assuming his approach to the "settling/sedimentation and rigidification debate". Based upon his distinction between settling and sedimentation and rigidification, Dr Farrow concluded that integers (a), (b) and (d) of claim 1 were not present. Her Honour, having accepted Dr Farrow's construction of the term "rigidification", found that the Bulga process did not disclose improved rigidification as described in the Patents. Again, Ciba did not seek to support her Honour's finding on any basis other than the distinction between settling and sedimentation on the one hand, and rigidification, on the other. Given my view concerning the construction question, and assuming that the case is not otherwise disposed of on appeal, I would set aside the finding and remit the question for further consideration.

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Beenup 199 Evidence concerning the Beenup mine process was given by Mr Cigulev, a metallurgist employed there from 1996 until 1999. He said that polymers were used as flocculants in the treatment of mineral sands tailings between 1997 and 1999. When he commenced work at the mine, difficulties were being experienced in recovering water from tailings slurry because the tailings involved slow-settling clay and sand. Much of the waste material was sludge or slime from which it took a long time to recover water. In order to accelerate the process he decided to add flocculant to the slurry at a number of places in the waste stream. He said: I recommended that flocculant be added both shortly before each of the outlet points being an open ended pipe that discharged the Tails Slurry into the [deposition area] and at the end of each of the outlet points. … The flocculant was added approximately 10 metres from each outlet point and also at the outlet point directly into the stream as it flowed into the [deposition area]. 200 He also said that the flocculant was in an oil emulsion and was activated with water as per the manufacturer's recommendation and that: Once the doses of flocculant were added, the slurry which was deposited in the [deposition area] separated into a solid clay and sand stack, and the clarified water could be reused. The process resulted in stacks of the sand and clay being formed in the [deposition area], that is, the floccs produced by the co-flocculation process were so rigid so as to stack rather than flow upon being deposited in the [deposition area]. Stacks rose in height forming a "volcano" and threatened to tower over the wall of the [deposition area]. 201 Her Honour accepted Mr Cigulev's evidence. Professor Slatter considered that all of the integers of the invention were disclosed on the basis of "his understanding of the settling/sedimentation and rigidification controversy". Dr Farrow explained the "volcanoes" referred to by Mr Cigulev as follows: While Mr Cigulev refers to a stack being formed, there is no evidence that this is a homogenous mixture of coarse and fine particles, rather than a segregated stack. In my opinion, the "volcanoes" he stated to build up rapidly would have been composed mainly of coarse material. The remainder of the solids would quickly run-off in suspension (probably causing significant erosion at the point of contact with the "volcanoes") and be deposited in a pool at the foot of the stack where they would settle or sediment out. My conclusion here is supported by Mr Cigulev's diagram of the process "JC-3". This shows a second addition point for the flocculant as the tailings are discharged into the disposal area. As also discussed above in relation to the process described in Mr Coleman's affidavit, what appears to be happening at Beenup is that as the polymer is added on discharge, the coarse and fine fractions immediately segregate causing the rapid build up of stacks of course material. Again I refer to page 3, line 3 onwards of the Patent, relating to the problems associated with such deposition including excessive beach angles and run off of aqueous waste contaminating recovered water. I would not consider the stacks to be rigidified. 202 The primary Judge disposed of this issue upon the basis of her construction of the word "rigidification" and has not dealt with the apparently conflicting evidence of Professor Slatter and Dr Farrow as to other grounds. Should the case not be resolved on some other basis, I would remit this question, including the issues raised by the notice of contention, for further consideration.

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INNOVATION 203 Relevantly, s 7 of the Patents Act provides: … Innovative step (4) For the purposes of this Act, an invention is to be taken to involve an innovative step when compared with the prior art base unless the invention would, to a person skilled in the relevant art, in the light of the common general knowledge as it existed in the patent area before the priority date of the relevant claim, only vary from the kinds of information set out in subsection (5) in ways that make no substantial contribution to the working of the invention. (5) For the purposes of subsection (4), the information is of the following kinds: (a) prior art information made publicly available in a single document or through doing a single act; (b) prior art information made publicly available in 2 or more related documents, or through doing two or more related acts, if the relationship between the documents or acts is such that a person skilled in the relevant art would treat them as a single source of that information. (6) For the purposes of subsection (4), each kind of information set out in subsection (5) must be considered separately. [Notes: (1) For the meaning of document see section 25 of the Acts Interpretation Act 1901. (2) See also the definitions of prior art base and prior art information in Schedule 1: see also paragraph 18(1)(b) and subsection 98(1).] 204 The term "prior art information" is defined in Schedule 1 relevantly as follows: (c) For the purposes of subsection 7(5) - information that is part of the prior art base in relation to deciding whether an invention does or does not involve an innovative step. 205 The definition of "prior art base" in Schedule 1 is relevantly as follows: (a) in relation to deciding whether an invention does or does not involve an inventive step or an innovative step: (i) information in a document that is publicly available, whether in or out of the patent area; and (ii) information made publicly available through doing an act, whether in or out of the patent area. 206 In considering innovation the primary Judge referred to the decision in Dura-Post (Aust) Pty Ltd v Delnorth Pty Ltd (2009) 177 FCR 239 at [73]-[74] and observed at [177] as follows: Accordingly, in determining the issue of innovative step, the court must ascertain: (a) the invention "so far as claimed in any claim"; (b) the person skilled in the relevant art; (c) the common general knowledge of the person skilled in the art as it existed in Australia before the priority date; and (d) whether, when considered from the perspective of a person skilled in the art, in the light of that common general knowledge, the invention as claimed only varied from the kinds of information in s 7(5) - here the cited prior art information - in ways that make no substantial contribution to the working of the invention as claimed. 207 Her Honour also referred to the following observation by Kenny and Stone JJ in Dura-Post: In substance, s 7(4) deems an invention as claimed to involve an innovative step unless the invention does not differ from the relevant prior disclosure in a way that makes the substantial contribution to the working of the invention as claimed - in the sense of the device or process the subject of each claim. This is a factual inquiry. The assessment is, of course, from the perspective of a person skilled in the art, having regard to the relevant common general knowledge. 208 The primary Judge observed that she had previously identified the relevant art and the skilled addressee and held that the skilled addressee was also a person skilled in the art. Her Honour then turned to the question of common general knowledge, observing at [180] that it: … "involves the use of that which is known or used by those in the relevant trade" and "forms the background knowledge and experience which is available to all in the trade in considering the making of new products, or the making of improvements in old, and it must be treated as being used by an individual as a general body of knowledge": see Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Ltd (1980) 144 CLR 253 at 295 (Aickin J). 209 Her Honour then referred to various other authorities concerning common general knowledge. At paras 184, 185 and 186 her Honour observed: 184. The Ciba respondents submitted that a body of prior art had been identified but there was limited evidence as to the common general knowledge of the skilled worker in the field. As the Ciba respondents noted, this is the context in which the person skilled in the art would consider whether the invention as claimed only varies from each piece of prior art information in ways that make no substantial contribution to the working of the invention. In this connection, the Ciba respondents noted, and SNF accepted, that none of the cited prior art documents had been shown to form any part of the common general knowledge in Australia at the priority date. 185. Notwithstanding this, some matters of common knowledge were clearly established. Industry witnesses, such as Messrs Bannister [sic], Coleman and Woolley, gave evidence (which I accept) that, before the priority date, they were familiar with the use of water-soluble polymers (including in high doses) as flocculants to dewater slurries of mining waste, as indicated in the belt press example given by Mr Schroeter. The evidence of industry witnesses was that before the priority date: (1) they knew that polymer might be added as flocculant in a number of ways - as powder, in emulsions or aqueous solution; and (2) they had for some years regularly added flocculant in aqueous solution to tailings slurries. I accept that this knowledge formed part of the common general knowledge before the priority date. Mr Schroeter also gave evidence that the use of polymers in emulsions, and their mode of activation, was known in the industry before the priority date. Given Mr Schroeter's long experience in the industry, I accept that this knowledge formed part of the common general knowledge before the priority date. 186. There was also evidence from industry witnesses that, as part of their common general knowledge before the priority date, they would have been aware that the flow properties of slurries are determined by the mineralogy and water content of the slurry, "applied shear" (as witnesses called it), and the polymer dose. Industry witnesses were also aware as part of their common general knowledge that: (1) mining tailings could be disposed of by pumping the tailings slurry through a conduit to a disposal area where the material could be allowed to stand, with a view to land reclamation and water recycling; (2) the addition of polymer as flocculant to a tailings slurry prior to, or during, pumping of the slurry to a disposal site enable the slurry to thicken and dewater more effectively upon standing; and (3) tailings slurries dosed with polymers in this way could be deposited at a disposal site in which the material would settle and form sediments. Further, as part of this common general knowledge, the industry witnesses knew that, generally speaking, the higher the flocculant dose, the greater the flocculation. The knowledge of these industry witnesses can to be taken to have formed part of the common general knowledge of a person skilled in the art before the priority date. 210 At para 3 of its notice of contention, Ciba gave notice that it proposed to support the judgment below, if necessary, upon the grounds that integers (f), (o) and (q), represented aspects in which the claimed invention varied from the prior art base in ways which make substantial contributions to the working of the invention. However, in its written outline and in its oral submissions on appeal, it did not pursue that contention. Counsel for SNF drew attention to this fact at ts 73 ll 1-2 and was not contradicted. Thus I proceed on the basis that Ciba seeks to uphold the judgment, as it deals with innovation, on the basis adopted by the primary Judge and does not rely on the notice of contention. 211 At [190] her Honour identified the following alleged variations as suggested by Ciba: settling as opposed to rigidification; whether the polymer is combined with the slurry material in the form of an aqueous solution; and whether the flocculant is added to the slurry material between the thickener and the deposition area. 212 However, on appeal, Ciba asserts that the relevant variations are: as to Slatter 10, Slatter 12, Slatter 13, Londonderry, Beenup and Bulga, "settling as opposed to rigidification"; and as to Slatter 3 and slatter 4, "whether the polymer is combined with the slurry material in the form of an aqueous solution". 213 In limiting my consideration of the case to those aspects, I do not seek to place upon Ciba, any burden of proof. I accept that SNF must demonstrate absence of an innovative step. However that does not preclude the long-established practice pursuant to which the parties generally identify the matters in dispute. Slatter 10, Slatter 12, Slatter 13, Londonderry, Beenup and Bulga 214 Insofar as concerns Slatter 10, Slatter 12, Slatter 13, Londonderry, Beenup and Bulga, the parties conducted the appeal on the basis that resolution of the construction question would resolve the innovation question. As I would resolve the construction question in favour of SNF, the result is that, as compared with the information in each of those Patents, each of the Patents lacks an innovative step.

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Slatter 3 and Slatter 4 215 Ciba submits that the claimed invention varies from the relevant prior art information in Slatter 3 and Slatter 4 only in that it teaches addition of the polymer in the form of an aqueous solution. Before considering this question, I should say something about the proper construction of s 7(4). Complex sections such as ss 7(1), 7(2) and 7(4) are frequently difficult to apply in practice. They prescribe very precise tests. As appears from the reasons in Dura-Post the concept of innovation is quite different from the concepts of novelty and inventiveness. These observations all underline the need for care in identifying the test to be applied pursuant to s 7(4). Approaches taken in considering novelty or inventiveness may not necessarily be appropriate in considering innovation. 216 Pursuant to s 7(1) the Court must compare the patent in suit, as understood by the skilled person, with an item of prior art as understood by that notional person. Section 7(2) addresses the notional opinion of a person skilled in the art who has read the patent in suit and considered the relevant items of prior art, in the light of common general knowledge. The relevant opinion is as to whether the invention is obvious, having regard to common general knowledge and the prior art. Section 7(4) also addresses the opinion of a person skilled in the art. That person is to compare the invention (as claimed in any claim) with, generally, prior art information in a single document, in the light of common general knowledge. 217 Section 7(4) poses two questions, namely: whether the invention varies from relevant prior art information; and if so, whether such variations make no substantial contribution to the working of the invention. It is not presently necessary to deal with s 7(5)(b). 218 I make a number of observations concerning s 7(4). First, as in the case of s 7(1), the test assumes the skilled person's understanding of both the patent in suit and the item of prior art. Secondly, it should not be assumed that a "variation" for the purposes of s 7(4) will necessarily be the same as an "integer" found to be missing in an item of prior art for the purposes of s 7(1). Thirdly, the comparison pursuant to s 7(1) is not informed by common general knowledge, although the construction of each relevant document may be so informed. Pursuant to s 7(4), the comparison is to be informed by common general knowledge. Fourthly, the second question is not concerned with inventiveness. It assumes that the skilled person has identified some variation between the patent in suit and relevant prior art information, and asks whether he or she would consider that such variation did not make a substantial contribution to the working of the invention. In other words, if a claimed invention is novel (within the meaning of s 7(1)), not inventive (within the meaning of s 7(2)), but varies from the relevant prior art information, it will be patentable, unless it is shown that the variations make no substantial contribution to the working of the invention. 219 The questions posed by s 7(4) are to be answered by the Court, putting itself into the position of the skilled person. The question of whether there is a variation may well be one of degree and judgment, and therefore may be more difficult to resolve than the second question. The latter may frequently involve only the acceptance or rejection of a mechanical explanation. 220 It should not be assumed that the skilled person's answer to the first question will necessarily be based upon a semantic analysis of the patent in suit and the prior art information in a document. There may be more subtle considerations in which an understanding of the inter-relationship of aspects of the invention leads to a different result from that which would arise from a semantic analysis, even if informed by evidence as to the skilled addressee's understanding of the patent in suit and the prior art. Further, differences in taxonomies may affect the answer to the question. The answer to the second question, as to substantial contribution, may be similarly affected. 221 I understand all of this to be consistent with the decision in Dura-Post. Indeed the primary Judge so directed herself when, at [178], she set out [79] from the Dura-Post judgment.

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Slatter 3 222 The primary judge observed that the industry witnesses had said that for some years prior to the priority date, a flocculant had been regularly added in aqueous solutions to tailings slurries. Professor Slatter said that as a matter of course, a flocculant could only be active when in solution, and that the effect of adding polymer in particulate form and in aqueous solution is the same. The polymer will only take effect when it dissolves. When a flocculant in particulate form is mixed with aqueous slurry, it dissolves in the slurry which generally contains water. Thus Professor Slatter considered that in the Slatter 3 process, there would be a delay in activation of the flocculant but, thereafter, the process would be the same as with the claimed invention, using a polymer solution. Professor Slatter also pointed out that the fact that an aqueous polymer solution would take effect more quickly was not necessarily an advantage, in that it might increase the risk of rigidification within the pipe and prior to deposition. He agreed that this consideration might suggest the use of the polymer in particulate form rather than in solution. 223 On the other hand, Dr Farrow's evidence was that the addition of the polymer in aqueous solution would act in a different manner, and have a different effect from the addition of polymer in other forms, including in particulate form. The primary Judge inferred that Professor Slatter's evidence, in substance, supported the proposition that the form in which the polymer was added would have a material effect on how the process worked, observing that his evidence in this respect was borne out by the evidence of industry witnesses. Mr Schroeter said that an emulsion might be used if one wanted to slow the process. Mr Banister agreed that the particulate form would act at a different rate from that of a solution. Mr Cigulev said that adding flocculant in forms other than solution was less effective. 224 At [197] her Honour then said: The evidence at trial therefore supports the conclusion that a person skilled in the art, in the light of the common general knowledge before the priority date, would consider the form in which the flocculant is added to have an important effect on the process. The evidence does not establish that the person skilled in the art, in light of relevant common general knowledge, would consider that the invention as claimed in each of the claims of Patent 944 only varied from Slatter 3 in a way or ways that make no substantial contribution to the working of the invention. SNF failed to discharge its onus of proof. Therefore, by virtue of s 7(4) of the Act, Patent 944 and the other patents in suit have an innovative step when compared to Slatter 3. 225 Her Honour, in connection with Slatter 3, considered only the second of the three variations identified by Ciba, the combination of an aqueous polymer solution with the slurry. Having concluded, for the purposes of s 7(1), that addition of the polymer in aqueous form was not anticipated, her Honour concluded that such addition was a variation from Slatter 3 and proceeded to consider whether or not such variation made a substantial contribution to the working of the claimed invention. In my view the proper approach was to ask whether the skilled person would consider that there was a variation between the Patents and the information in Slatter 3, and then to consider whether or not that variation made a substantial contribution to the working of the invention. Having regard to the common general knowledge as to the use of polymers in particulate form, in emulsions and in aqueous solutions, as found by her Honour, and to the fact that their mode of activation was known in the industry before the priority date, it seems quite likely to me, given my construction of Slatter 3, that the skilled person would read the paragraph at the foot of p 14 in Slatter 3 as disclosing the use of a pre-formed solution of a soluble polymer for the purpose of the Slatter 13 invention. If so, then the Patents would not vary from Slatter 3 in the way suggested by Ciba, namely in disclosing the use of a polymer in solution. However that question was to be answered having regard to the likely view of a person skilled in the art. Her Honour seems to have assumed that the absence of integer (e) was a relevant variation and to have proceeded accordingly. In my view the skilled person might not approach the question by dividing the invention into integers. Such a person would read the two documents and identify any variation for him- or herself. On my understanding of Slatter 3, he or she might conclude that addition of the polymer in aqueous solution, as part of the relevant process, appeared from the specification. It would follow that there was no relevant variation as between the claimed invention and Slatter 3. Of course, the question was to be considered from the point of view of the skilled person. It is not clear to me that there was any evidence as to how such a person would approach the question. 226 Assuming that the skilled person would identify the addition of an aqueous polymer solution as a variation from Slatter 3, the Court would then have to determine whether the skilled person would consider that such variation did not make a substantial contribution to the working of the claimed invention. The skilled person understood that use of such a solution would accelerate the process, and that use as an emulsion would slow the process. The skilled person also understood that use in particulate form would produce a different rate of reaction from use of the other forms. The skilled person knew that acceleration of the process might increase the risk of premature deposition. Her Honour concluded, apparently on the basis of this knowledge, that the skilled person would "consider the form in which the flocculant is added to have an important effect on the process", and that, therefore, SNF had failed to demonstrate that the skilled person would consider that the claimed invention only varied from Slatter 3 in a way or ways which made no substantial contribution to its working. 227 I accept for present purposes that the skilled person would have considered that the "form in which the flocculant is added" would have an "important effect on the process". However I am not sure that this proposition can necessarily be translated into negation of the proposition that addition of the polymer in aqueous form made no substantial contribution to the operation of the claimed invention. The use of a test expressed in terms more general than those prescribed in s 7(4) creates a risk of error. 228 Both questions were to be answered from the point of view of the skilled person. It is not clear whether there was any admissible evidence going directly to that matter. If it were otherwise necessary, I would conclude that the primary Judge had addressed the wrong question and remit it for further consideration. 229 As I have previously observed the notice of contention was not pursued in connection with the issue of innovation.

[59]

COSTS 232 Despite its failure at trial, SNF sought costs against Ciba in connection with an issue concerning a mining operation at Carborough Downs. The primary Judge declined the application, publishing reasons on 9 June 2011. SNF asserts that as it succeeded on that issue, it should have been awarded its costs as against Ciba, notwithstanding its failure in the action as a whole. This issue is relevant only if SNF's appeal is otherwise unsuccessful. 233 Costs are generally in the discretion of the Court. In House v The King (1936) 55 CLR 499 at 525-526, Dixon, Evatt and McTiernan JJ said: The manner in which an appeal against an exercise of discretion should be determined is governed by established principles. It is not enough that the judges composing the appellate court consider that, if they had been in the position of the primary judge, they would have taken a different course. It must appear that some error has been made in exercising the discretion. If the judge acts upon a wrong principle, if he allows extraneous or irrelevant matters to guide or affect him, if he mistakes the facts, if he does not take into account some material consideration, then his determination should be reviewed and the appellate court may exercise its own discretion in substitution for his if it has the materials for doing so. It may not appear how the primary judge has reached the result embodied in his order, but, if upon the facts it is unreasonable or plainly unjust, the appellate court may infer that in some way there has been a failure properly to exercise the discretion which the law reposes in the court of first instance. In such a case, although the nature of the error may not be discoverable, the exercise of the discretion is reviewed on the ground that a substantial wrong has in fact occurred. 234 In this case, the Carborough Downs operation was significant in two respects. First, SNF commenced these proceedings, seeking both declarations that the Patents were invalid and that threats were unjustifiable. The threats were contained in a letter from Ciba's solicitors, asserting that SNF was breaching the Patents by its conduct at Carborough Downs. SNF also alleged that Ciba had spoken to personnel at Carborough Downs, suggesting that use of the SNF process would infringe the Patents. Secondly, Ciba asserted, as a particular instance of infringement by SNF, that it had offered to use and implement the SNF process at Carborough Downs. Ultimately, it did not pursue that aspect of the case. 235 The primary Judge refused the application for costs, setting out the history of the proceedings. Her Honour noted that "the issue remained in pleadings on SNF's side throughout the trial". It is true that SNF persevered in its assertion that threats made in connection with Carborough Downs were unjustifiable. However, given SNF's concession as to infringement (if the Patents were valid) that assertion seems not to have required any close examination of the Carborough Downs operation. The question was as to the validity of the Patents. 236 In her Honour's reasons dated 9 June 2011, it was observed at [77] that: … Carborough entered the cross-claimant's pleading in particulars of infringement and loss and damage in the Further Amended Defence and Further Amended Cross-claim filed on 1 October 2009. A further affidavit of Mr Tobin was filed on 20 November 2009. Most references to Carborough were deleted from the Second Further Defence and Further Amended Cross-claim of 16 February 2010. Only one remained, again in particulars as to infringement: see reasons for judgment delivered 6 May 2011 at [302]: Senior counsel for the cross-claimant informed the Court in opening that Mr Tobin was not required for cross-examination, and that the cross-claimant accepted that the allegedly offending conduct had stopped. At this point, so senior counsel for the cross-claimant stated, the question as to Carborough was whether there was evidence to justify injunctive relief. Thereafter until closing submissions, the issue of Carborough was not agitated and, as I have already noted in reasons for judgment of 6 May 2012 [302], in closing, senior counsel for the cross-claimant confirmed that the case on infringement at Carborough was not pursued. 237 At [9] her Honour observed that: … Generally speaking, however, a trial judge will only order the successful party to pay the other party's costs of an 'issue' if the successful party's conduct at trial was such as to prolong unreasonably the proceedings or for some other like reason …. The conduct of (Ciba) in this case was not such as to justify an award of costs against it and in (SNF's) favour. 238 One circumstance in which such an order might be justified would be where the unsuccessful party had continued to incur costs in connection with an issue upon which it eventually succeeded, even if the length of the trial had not been extended. 239 It is curious that Ciba should have indicated, at the beginning of the trial, that it did not wish to cross-examine the relevant witness but did not, at the same time, indicate that it no longer wished to pursue the allegation of infringement. Such considered conduct might well have encouraged SNF to believe that the issue remained alive throughout the trial. Indeed that is probably the case. There is no suggestion that Ciba indicated to SNF at any time that it proposed not to press the Carborough issue. Ciba seems to have wanted to have it both ways: keeping open the issue in case something "came up", but doing so without exposing itself to the risk of having to pay any costs legitimately incurred by SNF in connection with that issue. If the matter were at large, I would have been inclined to make the order sought by SNF. However there is no reason to believe that her Honour did not consider such a possibility. In those circumstances I cannot conclude that the discretion miscarried. I would therefore dismiss the appeal against the order as to costs.

[67]

patent 944 249 The primary judge set out various parts of the specification of Patent 944 at [27]-[36] as follows: Patent 944 is headed "Treatment of Aqueous Suspensions". The specification begins with a brief statement of the subject to which the invention relates. This statement reads: The present invention relates to the treatment of mineral material, especially waste mineral slurries. The invention is particularly suitable for the disposal of tailings and other waste material resulting from mineral processing and beneficiation processes, including the co-disposal of coarse and fine solids, as a homogenous mixture. The specification describes two common ways of waste disposal, amongst other things, stating that where waste is not disposed of in a mine - … it is common practice to dispose of this material by pumping the aqueous slurry to lagoons, heaps or stacks and allowing it to dewater gradually through the actions of sedimentation, drainage and evaporation. The specification also describes an existing waste disposal method - "to load multiple layers of waste onto an area to thus form higher stacks of waste". However, this presents a difficulty of ensuring that the waste material can only flow over the surface of previously rigidified waste within acceptable boundaries, is allowed to rigidify to form a stack, and that the waste is sufficiently consolidated to support multiple layers of rigidified material, without the risk of collapse or slip. Thus the requirements for providing a waste material with the right sort of characteristics for stacking is altogether different from those required for other forms of disposal, such as back-filling within a relatively enclosed area. The specification gives the following account of an existing mineral processing operation: In a typical mineral processing operation, waste solids are separated from solids that contain mineral values in an aqueous process. The aqueous suspension of waste solids often contain clays and other minerals, and are usually referred to as tailings. These solids are often concentrated by a flocculation process in a thickener to give a higher density underflow and to recover some of the process water. It is usual to pump the underflow to a surface holding area, often referred to as a tailings pit or dam. Once deposited at this surface holding area, water will continue to be released from the aqueous suspension resulting in further concentration of solids over a period of time. Once a sufficient volume of water has been collected this is usually pumped back to the mineral processing plant. The specification notes that there are numerous difficulties with this kind of operation, including the size and costs of the tailings dam, the quality of the recovered water, and the composition of the dewatered solids. The specification refers to attempts to resolve these difficulties "by treating the feed to the tailings dam using a coagulant or a flocculant to enhance the rate of sedimentation and/or improve the clarity of the released water". The specification continues: However, this has been unsuccessful as these treatments have been applied at conventional doses and this has brought about little or no benefit in either rate of compaction of the fine waste material or clarity of the recovered water. Thus, so the specification says, "[i]t would … be desirable to provide treatment which provides more rapid release of water from the suspension of solids". In addition it will be desirable to enable the concentrated solids to be held in a convenient manner that prevents both segregation of any coarse and fine fractions, and prevents contamination of the released water whilst at the same time minimises the impact on the environment. The specification discusses at length the merits and demerits of various known treatment processes (the 'Bayer process', EP-A-388108, WO-A-96/05146 ('Slatter 4': see below) and WO-A-0192167 ('Slatter 3': see below)), concluding in relation to Slatter 3: However, despite the improvements brought about by [it], particularly in the treatment of red mud, there is still a need to further improve the rigidification of suspensions of materials and further improve upon the clarity of liquor released. The objective of the invention in Patent 944 is to improve upon Slatter 3. Thus the specification states: In particular, an objective of the present invention is to find a more suitable method for treating coarse and/or fine particulate waste material from mineral sands, alumina or other mineral processing operations in order to provide better release of liquor and a more effective means of disposing of the concentrated solids. Furthermore, there is a need to improve the dewatering of suspensions of waste solids that have been transferred as a fluid to a settling area for disposal and provide improvements in the clarity of run-off water. In particular, it would be desirable to provide a more effective treatment of waste suspensions transferred to disposal areas, for instance tailings dams, ensuring fast, efficient concentration and more environmentally friendly storage of solids and improve clarity of released liquor. The consistory clauses in Patent 944 commence with the statements: According to one aspect the present invention provides a process of improving rigidification of 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 aqueous solution of a water-soluble polymer … A significant part of the argument in this case focussed on the meaning of "rigidification" and cognate words. The outcome of much of SNF's challenge to validity depended on what was meant by this term. The Patentee observed that: The addition of the aqueous solution of water-soluble polymer to the material allows it to retain sufficient fluidity during transfer and then once the material is allowed to stand it will form a solid mass strong enough to support subsequent layers of rigidified material. We have unexpectedly found that the addition of the aqueous solution of polymer to the material does not cause instant rigidification or any settling of the solids prior to standing. Generally suspended solids will be concentrated in a thickener and this material will leave the thickener as an underflow which will be pumped along a conduit to a deposition area. The conduit is any convenient means for transferring the material to the deposition area and may for instance be a pipe or a trench. The material remains fluid and pumpable during the transfer stage until the material is allowed to stand. 250 The following should be noted: Patent 944 is titled "Treatment of Aqueous Suspensions", not limited to a particular process. The invention is said to relate to the treatment of mineral material, especially waste mineral slurries. The specification acknowledges certain matters as prior art: It is common to dispose of waste by pumping the aqueous slurry to stacks and allowing it to dewater through the action of sedimentation, although this has difficulties as described. Tailings are often concentrated by a flocculation process and, after deposition at a surface holding area, water will be released from the aqueous suspension, resulting in concentration of solids over a period of time. This also has the difficulties described. Attempts to resolve the difficulties by the use of flocculants to enhance the rate of sedimentation and/or improve the clarity of the released water are said to have been unsuccessful at conventional doses. A goal in the art is said to be concentrated solids held in a convenient manner that prevents both segregation of any course and fine fractions (homogeneity), prevents contamination of the released water and minimises the impact on the environment. The specification cites Slatter 3 and Slatter 4 as each disclosing known treatment processes. Following a discussion of Slatter 3, a goal in the art is said to be the improvement of the rigidification of suspension of materials and improvement on the clarity of the liquor released. The invention is said to provide a process of improving the rigidification of the material while retaining the fluidity of the material during transfer. 251 The meaning of rigidification is explained in Patent 944 in terms of 'once the material is allowed to stand it will form a solid mass strong enough to support subsequent layers of rigidified material'. However, this is only after the material has been transferred as a fluid and allowed to stand. The advantage of the claimed invention is that the addition of the aqueous solution of polymer does not cause instant rigidification, or any settling of the solids prior to standing. That is, the material remains fluid and pumpable during the transfer stage until the material is allowed to stand. 252 As noted by the primary judge at [40]-[41], the claims of Patent 944, separated into integers as agreed by the parties, are to: Integers of claim 1 (a) a process of improving rigidification of a material whilst retaining the fluidity of the material during transfer (b) 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 (c) by combining with the material during transfer (d) an effective rigidifying amount of (e) an aqueous solution of a water-soluble polymer having an intrinsic viscosity of at least 5 dl/g (measured in 1M NaCl at 25° C) (f) in which the material comprises coal tailings. Integers of claim 2 (g) a process according to claim 1 in which the water-soluble polymer is anionic (h) in which the polymer is formed from monomer(s) selected from the group consisting of (meth) acrylic acid, allyl sulphonic and 2-acrylamido-2-methyl propane sulphonic as the free acid or salts thereof (j) wherein the effective rigidifying amount of the water-soluble polymer is in the order of 10 to 3000 grams per tonne of material solids. Integers of claim 3 (k) a process according to claim 1 or claim 2 in which the material is pumped to an outlet (l) where it is allowed to flow over the surface of previously rigidified material and (m) wherein the material is allowed to stand and rigidify to form a stack. Integers of claim 4 (n) A process according to any one of claims 1 to 3 in which aqueous suspensions of fine and coarse particulate materials are combined for the purpose of co-disposal and (o) wherein the effective rigidifying amount of the water-soluble polymer solution is added during or after the mixing of the different waste streams into a homogenous slurry. Integers of claim 5 (p) A process according to any one of claims 1 to 4 in which the material is dewatered during rigidification, releasing liquor and (q) in which the clarity of the liquor is improved by the addition of an aqueous solution of water-soluble polymer.

[71]

The meaning of rigidification 260 At [45], her Honour noted that claim 1 is for a 'process of improving rigidification'. "Improve", as her Honour noted at [46]: … in this context, is to make "rigidification" greater in amount or degree; even "to increase the value or excellence" of "rigidification" as applied to the disposition of mineral waste… Reading the specification as a whole, the word "improve" necessitates a comparison - here with processes other than the claimed process. 261 As to rigidification, her Honour observed at [47] that: … the evidence establishes that "rigidification" is not a term of art. One may accept that, in ordinary usage, "rigidify" means "[t]o become rigid, set, or inflexible"; and "rigid" means, in relation to material, "stiff; not pliant or flexible; firm; hard". 262 There is no issue on appeal with respect to the ordinary meanings of "improve" and "rigidification". It is important to take into account, as her Honour did, that the word "rigidification" in the claim is in the context of a process of improving rigidification. 263 The question as, with respect, her Honour correctly observed at [47], is what the word "rigidification" signifies in the specification and claims of Patent 944. Her Honour recorded Dr Farrow's explanation of how the claimed process effected rigidification. That is not strictly relevant to the construction of the terms "rigidification" or "improving rigidification". It may simply have been helpful to her Honour in understanding the nature of the claimed invention in the context of a claimed improvement over existing processes of rigidification, including settling and sedimentation. 264 The primary judge accepted Professor Slatter's explanation that rigidification is a process of developing strength (in terms of yield stress). Her Honour noted Professor Slatter's evidence that, although it was enhanced by the addition of flocculant, stiffening or hardening could occur without the addition of flocculant. However, her Honour also noted Professor Slatter's acknowledgment that, in the context of the claimed process, time was 'critically important' in that rigidification 'must occur immediately after leaving the pipe but not before, so as not to impinge on fluidity in the pipe'. Professor Slatter acknowledged that Patent 944 seeks to bring about a faster process, such that 'not only is the material able to be rehabilitated, but that water can be recycled'. 265 The primary judge set out in detail Professor Slatter's evidence describing the importance of the minimisation of flow after the material is allowed to stand and the need for rapid solidification of the material. Her Honour also referred to the evidence of Mr Schroeter, SNF's managing director and Mr Bembrick, SNF's regional sales manager for Queensland, as to the increased and more rapid release of water in the SNF Process, which was also described as the "beaching" process. As noted earlier, the SNF Process is within the scope of the claims of Patent 944. 266 Dr Farrow said that "rigidification" was a qualitative term. Dr Farrow described the rigidification process of Patent 944 as one that: produced a different tailings deposit with different characteristics, different dewatering potential and in a different period of time to natural settling and sedimentation; produced rigidified tailings that would be less likely to spread laterally after deposition, enabling more efficient land use; produced rigidified tailings that more rapidly form a solid structure in the form of a beach or stack; produced rigidified tailings that have a greater yield strength when deposited; produced rigidified tailings that have increased uniformity or homogeneity of fine and coarse particles; produced rigidified tailings that, by reason of its heaped geometry, result in downward compression forces driving water out of the stack; produced rigidified tailings that result in more rapid improved clarity of water release; and results in a very significant increase in the rate and extent of water release. 267 Dr Farrow described the rigidification process of Patent 944 as being 'an entirely different process to that of settling and consolidation'. Her Honour accepted this evidence and observed at [66] that Mr Schroeter had no difficulty in distinguishing the SNF Process from a settling process. In his evidence Mr Schroeter described the general process in terms of an unhindered sedimentation process, where the larger particles settle by flowing through water to a hindered settling process, where the particles are in contact with each other. This is followed by a compaction phase, where the particles are fully in contact and the water works its way out as the gravity compression of the particles increases. He described that as subsurface sedimentation, in contrast to the SNF Process. He described the differences between a settling and sedimentation process and one which uses quantities of flocculants where there is a more structured sludge and the water is driven out and discharged far more rapidly. 268 In her conclusion, the primary judge said that to the extent that Dr Farrow's evidence was inconsistent with that of Professor Slatter on the issue of rigidification, she accepted the evidence of Dr Farrow. Further, her Honour observed that Professor Slatter's evidence and conclusions contradicted those of Messrs Bembrick and Schroeter. 269 Her Honour said that the meaning that Dr Farrow accorded to rigidification 'accorded with the natural meaning of the word, considered in the context of the specification as a whole' in contrast to a focus on individual words and phrases within the specification. Her Honour rejected SNF's submission that concepts of speed or time were not essential to claim 1, noting that speed and time are inherent in the 'process of improved rigidification'. Further, her Honour concluded, the process as taught and claimed in Patent 944 does not encompass settling and sedimentation. 270 At the heart of SNF's submissions are the following contentions, as set out in its written submissions in reply: The claims of Patent 944 make no reference to "networking". Claim 1 of Patent 944 makes no reference to rapid dewatering. Claim 5 does refer to dewatering but not to rapid dewatering. "Stand and rigidify", as used in claim 1, means to become stationary and to harden. The primary judge erred in importing into the construction of claim 1 the evidence of Dr Farrow because: it was not a matter of applying Dr Farrow's evidence; Dr Farrow's view was not adopted by the trade witnesses and was inconsistent with findings on common general knowledge; and Dr Farrow applied a definition not supported by the natural meaning of the claims and specification. 271 SNF accepts that the primary judge took the correct approach in asking what the word "rigidification" signifies in the context of the specification and claims of Patent 944. However, SNF submits that there was no proper basis to interpret the term in the manner contended for by Dr Farrow. In particular, SNF submits that there was no good reason to exclude the process of settling and sedimentation from the scope of claim 1. SNF criticises Dr Farrow's view as importing into the term "rigidification" a process in which a networked structure is formed, which itself excludes the processes of settling and sedimentation. SNF contends that Dr Farrow's evidence on this issue was not in keeping with the understanding of the skilled addressee and that it was at odds with the language of the claims and specification. SNF points out that there is no reference to networking in the specification or the claims. SNF says that there is nothing in the consistory clause of Patent 944 covering networking, nor a directional requirement that improved rigidification will only occur where there is networking. Indeed, SNF points out, the specification leaves it entirely open as to how the asserted improvement occurs, so long as there is the addition during transfer of increased flocculant at the dosage points. 272 The specification describes the prior art mineral processing operation as follows: Waste solids are separated from solids that contain mineral values. The waste solids are in aqueous suspension (tailings). The solids are often concentrated by a flocculation process to give a higher density underflow and to recover some of the processed water. The underflow is pumped to a surface holding area, a tailings pit or dam. Once deposited, water will be released from the aqueous suspension, resulting in further concentration of solids over a period of time. Once a sufficient volume of water has been collected, it is pumped back to the mineral processing plant. 273 The specification notes the difficulties and inadequacies of this process and refers to prior art methods of using a coagulant or a flocculant to enhance the rate of sedimentation and/or to improve the clarity of released water. The specification notes that these treatments have been unsuccessful with little or no benefits in either rate of compaction or clarity of the recovered water. In that context, the specification describes the desirability of providing a treatment for more rapid release of water from the suspension of solids. It also describes a need further to improve 'the rigidification of suspensions of materials and further improve upon the clarity of liquor released'. In particular, the stated object of the invention is to improve upon the process of Slatter 3, including a means of ensuring fast and efficient concentration and improved clarity of released water. 274 It is in this context that the specification refers to the invention 'improving rigidification of a material whilst retaining the fluidity of the material during transfer' such that the material is transferred as a fluid to the deposition area and then allowed to stand and rigidify. This is achieved by the use of 'an effective rigidifying amount' of aqueous solution of a water-soluble polymer. The addition of that aqueous solution of a water-soluble polymer allows it to retain sufficient fluidity during transfer and then, on being allowed to stand, to form a solid mass strong enough to support subsequent layers of rigidified material. 275 In that context it is clearly apparent that the improved rigidification process of Patent 944 was different from prior art processes of settling and sedimentation and did not include them. Although Professor Slatter said that settling and sedimentation always leads to rigidification, the improved rigidification of claim 1 and of the invention was contrasted with the "natural" rigidification process brought about simply by settling and sedimentation, despite the fact that flocculation was used in the process. 276 Dr Farrow's explanation of a networked structure formed the basis of Ciba's approach to the effect of improved rigidification, in part to explain its meaning, in that he explained the way in which the claimed process worked. However, there is no requirement for the patentee to provide an explanation of how the invention works. In any event, as noted by Ciba, there is nothing in the specification inconsistent with that explanation, nor is networking a requirement of the claims. Ciba emphasises that the non-chemist skilled addressee does not need to know networking to work the invention. 277 The construction of the claim in the context of the specification does not depend on, or take account of, the concept of a networked structure or the evidence in relation to it. 278 Relevantly, her Honour concluded that practical people working in the field such as Mr Bembrick had no difficulty in distinguishing between a process leading to improved rigidification in accordance with the patent's process and the process of settlement or sedimentation. The evidence was that practical people routinely undertook testing of the kind necessary to implement the process successfully. Mr Bembrick described the technology at the level of "bucket chemistry". 279 In my view, the primary judge's conclusion on the construction of the word "rigidification" in Patent 944 was correct. I will now turn to consider the remaining relevant findings of the primary judge, together with the issues in the appeal.

[73]

Additional matters arising from Patent 944 282 Patent 944 acknowledges prior processes which involve the pumping of waste materials as slurry which is allowed to dewater, leaving the sedimented solids in place. Patent 944 acknowledges that it is common practice to use flocculants to assist this process to increase the rate of sedimentation. However, Patent 944 notes, in such cases the coarse material will normally sediment at a faster rate, resulting in a heterogeneous deposit of coarse and fine solids. The same applies to the waste solids or tailings that result from a typical mineral processing operation. Those waste solids are also often concentrated by a flocculation process in a thickener to give a higher density underflow and to recover some of the process water. The thickener is the vessel in which a suspension containing solids is flocculated in order to separate the suspension into a supernatant layer and an underflow layer. Once deposited in a tailings pit or dam, water is released from the aqueous suspension, resulting in a further concentration of the solids over a period of time. 283 The identified problem is that the tailings dam is often of limited size and tends to have a gently sloping bottom. Patent 944 also states that 'a problem that frequently occurs is when fine particles of solids are carried away with the run-off water, thus contaminating the water and having a detrimental impact on the subsequent uses of the water'. It is also said to be desirable to dispose of coarse and fine waste particles as a homogeneous mixture. 284 The specification states that attempts to overcome the above problems by treating the feed to the tailings dam using a coagulant or a flocculant to enhance the rate of sedimentation and/or improve the clarity of the released water have been unsuccessful. The "goal" was said to be to provide treatment which provides more rapid release of water from the suspension of solids, to hold the concentrated solids in a manner that prevents segregation of coarse and fine fractions and prevent contamination of the released water while minimising the impact on the environment. 285 The specification then makes specific reference to two earlier patents, referred to in these proceedings as Slatter 4 and Slatter 3. 286 Slatter 4 is said to describe a process of stacking an aqueous slurry. This comprises admixing an emulsion of a water-soluble polymer dispersed in a continuous oil phase with the slurry. It is a requirement that the polymer is not added into the slurry as an aqueous solution. 287 Slatter 3 is said to describe 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 a water-soluble polymer. This treatment enables the material to retain its fluidity as it is being pumped, but to rigidify on standing. This process is said to have the benefits that: concentrated solids can be easily stacked; and in comparison with the use of cross linked water absorbent polymers, water from the suspension is released rather than being absorbed and retained by the polymer. As the specification says, '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'. 288 The process in Slatter 3 is said to result in what could be described as improved rigidification. 289 However, the specification then states that despite that improvement, there is a need further to improve the rigidification of suspensions of material and further to improve the clarity of liquor released. The specification says that the present invention provides such an improved process. Recognising the importance of retaining sufficient fluidity during transfer, the specification states that the inventors 'have unexpectedly found that the addition of the aqueous solution of polymer to the material does not cause instant rigidification or substantially any settling of the solids prior to standing'. 290 Patent 944 states that the material can typically be treated at any suitable point after flocculation in the thickener but before the material is allowed to stand. Patent 944 emphasises the importance of the addition of a solution of water-soluble polymer. It adds that, when aqueous suspensions of fine and coarse particle materials are being combined for the purposes of co-disposal, the effective rigidifying amount of water-soluble polymer solution will normally be added during or after the mixing of the different waste streams into a homogenous slurry. 291 Patent 944 identifies the importance of the rheological characteristics of the material as it flows through the conduit to the deposition area and the rheological characteristics of the material as it rigidifies. Both are important to the efficiency of the mining operations and the minimisation of the flow of waste material. Patent 944 states that preferably the process of the invention will achieve a heaped disposal geometry and will co-immobilise the fine and coarse fractions of the solids in the material and also allow any released water to have a higher driving force to separate it from the material, that is, an enhanced rate of dewatering.

[75]

Slatter 3 295 Slatter 3 is a patent with an international filing date of 22 May 2001. Ciba is the patentee. 296 The specification of Slatter 3 states that the invention relates to the treatment of mineral material, especially waste from the Bayer alumina process, including the treatment of red mud waste in order to render it more easily disposable. The waste material is said to consist of an aqueous slurry or sludge comprising particulate mineral material and the specification also says that is normally necessary to dewater the waste slurries or sludges before disposal in a suitable location. The specification describes similar reasons for the need for a process to dispose of red mud by way of stacking. It states that, to be suitable for mud stacking, the mud should have a higher solids content and, when stacked, should not flow but should be relatively rigid in order that the stacking angle should be as high as possible, so that the stack takes up as little area as possible for a given volume. At the same time, the material must remain pumpable as a fluid. 297 The specification identifies a need to provide a process that will effectively and conveniently allow the material to be pumped readily as a fluid and which on standing will rigidify to provide a stackable solid waste. It states that there also exists a need to achieve this by substantially reducing the amount of aqueous fluid contained in the material. 298 The key aspect of the invention of Slatter 3 is a process 'in which material comprising an aqueous liquid with dispersed particulate solids is pumped as a fluid then allowed to stand and rigidify'. It is said that the rigidification is improved while retaining pumpability 'by combining polymeric particles with the material during or prior to pumping the material, wherein the polymeric particles comprise water soluble polymer'. The specification states that 'we have surprisingly found that the presence of water-soluble polymers applied in the form of particles actually enables the material to remain fluid and pumpable during the pumping stage but results in a rapid loss of fluidity and rigidity and rigidification on standing'. Again, it states that 'application of the particulate water soluble polymer' gives pumpable material. 299 Thus, in the invention of Slatter 3, 'the polymeric particles' are added. Alternatively, 'the water soluble polymer particles may be provided as a dispersion in an aqueous medium' and a particularly preferred form of the invention is one in which the polymer particles are in the form of an aqueous dispersion. In this context, Slatter 3 states, in a passage particularly relied upon by SNF: It is surprising that the process according to the invention forms a product which rigidifies far better than alternative treatments, for instance the use of water swellable polymers or pre-formed solutions of water soluble polymers. It is also surprising that especially good results are obtained by employing solid grade particulate polymers, comprising solid grade polymer, comprising individual large sized polymer particles as described herein. The process of the invention more effectively minimises the area taken up by a stack of the material of given volume. This is achieved whilst maintaining a pumpability of the material. Again it is said to be an advantage of the addition of material in powder form that the viscosity does not increase or diminish as rapidly as would a solution based addition. 300 The primary judge considered the opinions of the experts as to the disclosures of Slatter 3. Professor Slatter apparently considered that all integers of the claims of the Patent were present in Slatter 3. Dr Farrow deposed that integers (e), (n), (o), and (q) of the claims were not present. Her Honour noted at [87] that at trial 'the only issues with respect to Slatter 3 centred on integers (e) and (o)'. 301 Her Honour noted SNF's argument that there was 'sufficient disclosure of the use of an aqueous solution of water-soluble polymers in the treatment of mining slurries to achieve the promised effect of rigidification'. SNF relied upon the reference to the use of pre-formed solution of water-soluble polymers, as the alternative treatment that was said in Slatter 3 not to provide rigidification that was as good as the process of the invention, which contained additions in powder form. The additional passage to which SNF referred was 'one advantage of additions in powder form is that the viscosity does not increase or diminish as rapidly as a solution-based addition'. 302 Dr Farrow explained in his evidence the effect of the addition of aqueous solution of polymer when compared to the addition of solid particles, in the context of his discussion of Slatter 3 (at [95]). He said that the fully solubilised form was beneficial compared to the use of polymeric particles where the molecules would be clumped together. 303 Professor Slatter said, in evidence that was not challenged, that Slatter 3 describes fine and coarse particulate material being combined and that the polymer additive should be added during or after the fine and coarse particulate materials have been combined. 304 Professor Slatter equated the disclosure of the polymer emulsion with the disclosure of the polymers in an aqueous solution. Dr Farrow did not. 305 Professor Slatter accepted that a teaching that the polymer is insoluble in solution is not the same teaching as the administration of an aqueous solution of the polymer. He also agreed that particulate matter in an aqueous medium means that the particulate matter is not dissolved. 306 Her Honour preferred Dr Farrow's analysis, accepting that Slatter 3 recommends against the addition of polymer in an aqueous solution and in favour of the use of polymer in particles (at [96]). That is, her Honour found that Slatter 3 distinguishes between aqueous solutions, emulsions and dispersions. Accordingly, her Honour concluded that integer (e) was not present in Slatter 3. 307 As part of her consideration of the prior art information, by way of an introduction and overview of her approach, the primary judge noted a submission from SNF to the effect that there was a difference between a disclosure in a prior document of something said to be known or done and a stated preference for another option. SNF had apparently submitted that there is a difference between a disclosure in a prior document of something said to have already been done and a disclosure of a preference for another option, or a more limited or incidental disclosure, in the course of discussing or "teaching" that other option. 308 A prior publication will constitute an anticipation if it discloses all of the essential integers of the claim. In the present case the claim is for a process consisting of a number of integers in combination. The prior art publication must disclose those integers in that combination in order to deprive the later patent of novelty. Both parties referred to Hill v Evans (1862) 1A IPR 1 where Lord Westbury set out the well-known principles that have been adopted and applied in more cases over the years than can conveniently be set out here. Of particular relevance to the present case is Lord Westbury's statement at 7 that: Apparent generality, or a proposition not true to its full extent, will not prejudice a subsequent statement which is limited and accurate, and gives a specific rule of practical application. 309 A number of cases that have discussed Hill v Evans have done so in a context where there has been insufficient actual disclosure of the integers of a later claim but it is said that sufficient information has been disclosed or taught to amount to an anticipation. Reference may again be made to another statement of Lord Westbury at 7: Again, it is not, in my opinion, true in these cases to say, that knowledge, and the means of obtaining knowledge, are the same. There is a great difference between them. To carry me to the place at which I wish to arrive is very different from merely putting me on the road that leads to it. There may be a latent truth in the words of a former writer, not known even to the writer himself; and it would be unreasonable to say that there is no merit in discovering and unfolding it to the world. Upon principle, therefore, I conclude that the prior knowledge of an invention to avoid a patent must be knowledge equal to that required to be given by a specification, namely, such knowledge as will enable the public to perceive the very discovery, and to carry the invention into practical use. It was this passage from Hill v Evans that developed into the well-known test of "planting the flag" in General Tire & Rubber Co v Firestone Tyre & Rubber Co Ltd (1971) 1A IPR 121; see also H Lundbeck A/S v Alphapharm Pty Ltd (2009) 177 FCR 151 at [161]-[192]. 310 However, relevantly for this appeal, it is not submitted that there are any "signposts" in Slatter 3 that, in the sense described by Gummow J in Nicaro Holdings Pty Ltd v Martin Engineering Co (1990) 91 ALR 513, may be sufficient to disclose an integer to the skilled reader even where that integer is not clearly set out in the text. This is not such a case. Here the question is whether each of the integers of the claim has been disclosed in Slatter 3. This is not necessarily just a matter of looking at the words but involves considering what the passages relied upon would have disclosed to the skilled reader as at the priority date. 311 As submitted by Ciba, the following propositions are particularly relevant: Each integer of the claimed process must be in the prior document (Lundbeck at [169], [171]). A prior publication does not invalidate a patent unless it supplies sufficient information to enable a person of ordinary skill to produce the thing subsequently claimed (Lundbeck at [173]). The information as to the alleged invention given by the prior publication must, for the purposes of practical utility, be equal to that given by the subsequent patent. The question is not whether the claimed invention had previously been made, but whether it had been made known (Lundbeck at [174]). The prior art must disclose an invention which, if performed, would necessarily infringe the patent (Lundbeck at [189]). It is not enough to prove that something described in an earlier publication could have been used to produce the desired result; it must also be shown that the earlier publication contain clear and unmistakable directions to use it; the alleged anticipation must teach in the sense of direct, recommend or suggest the invention claimed (Bristol-Myers Squibb Co v FH Faulding & Co Ltd (2000) 97 FCR 524 at [67]). 312 SNF submits that sufficient disclosure has been made if the prior document clearly refers to something that has been done or is known but then says it will be better to carry out the process another way. SNF criticises the primary judge's use of the expression "teaching away" in the context of novelty and presses for the assessment of disclosure. SNF submits that the only question before the primary judge was whether or not integer (e) was itself disclosed. 313 A discussion of "teaching away" tends to be relevant to questions of obviousness, not to questions of novelty. However, as I have said above, it is necessary to look at the disclosures in context (Sigma Pharmaceuticals (Australia) Pty Ltd v Wyeth [2011] FCAFC 132 at [30]-[35]). It is a question of the disclosure to the skilled reader. 314 SNF argues against a consideration of the words that refer to an aqueous solution of water-soluble polymer in the context of the whole of the prior publication. However, it is necessary to understand the context in order to ascertain whether or not the integer was in fact disclosed and, importantly, disclosed as part of the claimed process. 315 This is not a case where Slatter 3 is said to contain clear and unmistakable directions to carry out the claimed process. There is no relevant signpost on the road to the patentee's invention. The key question, in determining whether Slatter 3 discloses the combination of the claims of Patent 944, is whether Slatter 3 discloses the combination of integer (e) with the other integers of the claimed process. It is not sufficient if, in the context of Slatter 3, the disclosure is of integer (e) alone. 316 The references within Slatter 3 to the use of pre-formed solutions of water-soluble polymers are limited. The disclosure is in terms of alternative treatments but does not descend into the detail of those alternative treatments. In context, Slatter 3 clearly refers to a process resulting in rigidification. However the following is not clear: whether the process using the water-soluble polymers is a process for improving rigidification where it is stated that an advantage of the addition in powder form is that the viscosity does not increase or diminish as rapidly as the solution based addition; whether the use of water-soluble polymers results in a process which retains the fluidity of the material during transfer; whether the waste material is transferred as a fluid to the deposition area and only then allowed to stand and rigidify; and whether the water-soluble polymer is combined with the material during transfer. 317 I accept that integer (e) is, of itself and in isolation, disclosed. However, it is not disclosed as part of a process which includes the remaining integers of the claimed process, nor is there a "teaching", in the sense of a recommendation, a direction or a signpost that discloses or results in those other integers being present. To the contrary, the warning in Slatter 3 that viscosity may increase or diminish rapidly with a solution based addition argues against its use with the material such that the requisite fluidity is maintained. 318 Consideration of the reasoning of Black CJ and Lehane J in Bristol-Myers at [71]-[72] does not affect the proper conclusions to be drawn from Slatter 3. Their Honours were there considering a disclosure of an administration schedule that proved to be feasible in respect of a particular drug. In context, the question of whether the particular publication anticipated the claimed invention involved a consideration of whether or not the prior publication gave a direction or made a recommendation or suggestion that, if the skilled reader followed it, would result in the claimed invention, either expressly or implicitly (at [67]). Their Honours noted the acceptance by counsel in that case that mere speculation as to whether a method subsequently claimed would work would not of itself destroy novelty and said at [68] that 'the question is still, what does the prior publication teach?'. 319 In my view, their Honours were not there referring to what a prior publication discloses where all integers are said to be disclosed. The word "teach" in that context was an examination of something less than an actual disclosure of all integers, as discussed in General Tire, Nicaro and Lundbeck. There may be a direction capable of being carried out in a manner which would infringe the patentee's claim; there may be a disclosure to the skilled addressee of a "missing integer" within the context of the prior publication. Their Honours said at [72] that 'there can be no serious doubt that the abstract teaches the shorter infusion period'. As I understand what was meant, this was an acceptance that the abstract did disclose the shorter infusion period to the skilled reader. 320 The Full Court in Merck & Co Inc v Arrow Pharmaceuticals Ltd (2006) 154 FCR 31 reached a similar conclusion as to the analysis in Bristol-Myers. Their Honours pointed out at [110] that the use of the word "teach" was in the sense of 'direct, recommend or suggest'. The Court also pointed out that a characterisation of an alleged anticipation as a suggestion is not necessarily fatal to a novelty argument but emphasised that the question was whether or not there was disclosure. That is, as stated in Hill v Evans: The invention must be shewn to have been before made known. Whatever, therefore, is essential to the invention must be read out of the prior application. [emphasis added] 321 Lundbeck contains other observations relevant to the novelty issues in this appeal (at [169]-[188]): If the prior publication contains a definite statement of facts and material from which the ordinary skilled addressee would clearly infer the existence of the integers of the claim, this is sufficient for an anticipation. The question is whether the prior publication is sufficient to make the claimed invention apparent to the skilled addressee. A prior publication does not invalidate a patent unless it supplies sufficient information to enable a person of ordinary skill, having at least the common general knowledge of the art, to produce the product subsequently claimed. Prior knowledge of an invention must be knowledge equal to that required to be given by the patent if it is to invalidate it. If prior information discloses some but not all of the integers of a claimed patent, there is anticipation if the skilled addressee would add the missing information as a matter of course and without the application of inventive ingenuity. The skilled addressee must be able to add what is missing in the prior information to obtain the claimed invention. Where there is an asserted prior use, what the skilled addressee observes on inspection must be sufficient to enable him or her to comprehend the complete invention. That is, it must be sufficient to amount to a disclosure to the skilled addressee of the claimed invention. The prior art must disclose subject matter which, if performed, would necessarily result in infringement of the claims of the patent. 322 SNF does not, in the appeal, rely upon the "teaching" of Slatter 3. It relies upon actual disclosure despite the absence of explicit disclosure of the other integers of the claim and process of Patent 944. However, as stated in General Tire, to anticipate the patentee's claim the prior publication must then contain clear and unmistakable directions to do what the patentee claims to have invented. Slatter 3 does not direct the use of an aqueous solution of water-soluble polymers as a process for improved rigidification. 323 SNF submits that anticipation should be tested by asking whether the skilled addressee who applied the teaching that polymers could be of an aqueous solution would inevitably have infringed the claims of the patent. It submits that the answer must be "yes", as all other integers of claim 1, including rigidification as defined by Dr Farrow, would clearly be present. However, there is no direction in Slatter 3 to use polymers in an aqueous solution and no evidence that the skilled reader would read Slatter 3 as recommending or disclosing that such a course would produce a process of improving rigidification. To the contrary, as the primary judge concluded at [96], based on Dr Farrow's analysis and Professor Slatter's concession, Slatter 3 recommends against the addition of polymer in aqueous solution. 324 Slatter 3 cannot be said to provide sufficient disclosure to constitute an anticipation of the process of claim 1 of Patent 944. 325 In circumstances where there has not been an anticipation of claim 1 by Slatter 3, it is not necessary to consider whether the additional integer (o) of claim 4 of Patent 944 is disclosed, as was raised in Ciba's notice of contention.

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Slatter 4 326 The specification of Slatter 4 states that the invention is generally directed to processes for stabilising the flow characteristics of fluid slurries of solids to permit the slurries to be stacked in piles. The invention more specifically relates to processes by which mineral slurries, such as the tailings produced by mineral extraction processes, may be treated so that they are disposed of in a more efficient, cost-effective manner. 327 The specification notes that water-soluble polymeric emulsions have been used as flocculants, generally in the form of inverted dilute solutions, in dewatering applications for solid liquid separations. It states that it has surprisingly been discovered that water-soluble polymers in the form of an inverse (water in oil) emulsion can be used to stabilise slurries and that the 'stabilizing effectiveness of the water-soluble polymers is surprisingly enhanced when they are used in their inverse emulsion form, rather than first being inverted to form a dilute aqueous solution, as such polymers are typically used in the art'. 328 Claim 1 of Slatter 4 is to 'a process for stabilising an aqueous slurry of particular soils which comprises: admixing an emulsion, in an amount sufficient to stabilize said slurry, with said slurry, said emulsion having a discontinuous phase comprising a water-soluble polymer'. 329 The primary judge noted that the evidence established that it was commonly accepted by persons skilled in the field of mining waste disposal in the context of Slatter 4 that before an emulsion becomes effective it must be "flipped", that is, dissolved in solution. As noted by the primary judge at [103], SNF argued that the application of the process of Slatter 4 'will inevitably entail the combination of polymer dissolved in aqueous solution with the slurry tailings'. 330 The primary judge accepted Dr Farrow's analysis of Slatter 4 over that of Professor Slatter. The primary judge said at [107]: Dr Farrow's point is that the aqueous phase of an emulsion is not an aqueous solution. This is reflected in Slatter 4, which contrasts emulsions with water-soluble polymers in dilute aqueous solution. Her Honour said that Slatter 4 taught the use of emulsions rather than of aqueous solutions and concluded at [109] that integer (e) of claim 1 of Patent 944 was not present. It followed that her Honour found the Patents novel over Slatter 4. 331 SNF submits that even though the examples in the specification of Slatter 4 show the use of polymers in aqueous solution for slump tests less successfully than in the case of material treated with emulsions, there is clear disclosure of the use of water-soluble polymers as typically used in the art. 332 Ciba's primary submission is straightforward: the aqueous phase of an emulsion is not an aqueous solution. Ciba points to the evidence, including the cross-examination of Professor Slatter, where he did not disagree with Dr Farrow that the properties of flocculant molecules in an aqueous solution are very different from those in a water in oil form. Ciba also points out that while the examples of Slatter 4 used polymer in aqueous solution for slump tests, those examples were unsuccessful. Ciba submits that Slatter 4 directs and discloses that the method is to avoid using aqueous solutions but rather to use emulsions. Ciba also submits that the reference to stacking in Slatter 4 is not synonymous with improved rigidification and that stacks were acknowledged in Patent 944 as part of the prior art. 333 In context, the disclosure in Slatter 4 of an aqueous solution of water-soluble polymer is not for use in the process of improved rigidification. There was no clear and unmistakable direction to use a process that necessarily would have included a solution of water-soluble polymers within the meaning of General Tyre. Claim 1 of Slatter 4 is a process for stabilising the slurry. It is to that to which Slatter 4 is directed. Slatter 4 does not disclose integer (e) of Patent 944. Further, it is not clear that the remaining integers of claim 1 of Patent 944, in particular, a process of improved rigidification and fluidity during transfer which is then followed by allowing the material to stand rigidified, are disclosed. 334 Slatter 4 does not anticipate the claims of Patent 944. 335 As agreed, it is unnecessary to deal with Slatter 10, Slatter 12 and Slatter 13 in light of the construction of the term "rigidification" explained above.

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The Londonderry Mine 337 As set out by the primary judge, SNF adduced evidence from Mr Woolley about the use of polymers in the process of treating mineral sands tailings at the Londonderry Mine in or around 1981 to at least 1989. Mr Woolley was employed to sell flocculants in the mining industry. Her Honour accepted Mr Woolley's evidence, which included the fact that he had tested and implemented a "super flocculation" process at the Londonderry Mine. Mr Woolley described super flocculation as the starting process of solids rigidification. His evidence was that the process involved adding flocculant solution to slurry after the slurry had passed through a hydrocyclone at a minimum of two points during the transfer of the slurry to the deposition area. The process caused the solids in the tailings to separate very rapidly from the water and, as a result, solids stacked up at the end of the pipe, which deposited the tailings in the deposition area. In Mr Woolley's words, 'the super flocculated tailing solids settled at or near the tailings discharge pipe and continued to build up forming stacks'. This process resulted in a dramatic speeding up of the timing after which the deposits could be reworked. However, in cross-examination, he said that the fine particles were the fine sand, the tailings were the clays and that the flocculant causes the fine particles to settle in the tailings dam. He agreed that the process was that the water sits in the pond, the discharge falls into it and the solids sink to the bottom and build up in the tailings dam. 338 SNF adduced evidence from Mr Coleman, who also worked in the mining industry, as to the use of polymers in the process of treating mineral sands tailings at the Londonderry Mine. Mr Coleman's evidence was to the effect that the problem at the Londonderry Mine was that the high content of fine particles of clay prevented the recovery of good quality water from the deposition area. The process then adopted was to add high doses of flocculant to the tailings stream in a number of locations while the stream travelled through the transfer pipe to the dam. The flocs formed would separate from the water in the tailings dam upon standing. Flocculant was also added to the waste slurry stream as it entered the tailings dam which caused the formation of stacks. The stacks would dewater, allowing further water to be recovered. He said that the clarity of the water, indicating that it was free of solids, was used as a parameter to ensure that the operation was running efficiently. Mr Coleman also said that the stacks that he saw were homogenous stacks of coarse and fine particles and included the finest particles in the original slurry. 339 Mr Coleman's evidence was accepted by the primary judge as confirming the description given by Mr Woolley, including in relation to the addition of flocculant to the overflow from the hydrocyclone, the clarity of water released and the formation of stacks compacted in a homogenous mass that could be walked over within six weeks. As her Honour noted at [145], the issue between the parties with regard to Mr Woolley's evidence was whether the deposition of flocculated fine particle slurries in the deposition area was characterised as settling/sedimentation or as rigidification. 340 As to this issue, Ciba relied on the evidence of Dr Farrow, who expressed the view that the photographs taken by Mr Woolley did not show any evidence of the formation of the stacks deposit with any real structure or strength or homogenous distribution. Dr Farrow said that it appeared to him that what had occurred was really sub-surface settlement or sedimentation. Her Honour observed that Dr Farrow also noted that the stacks described by Mr Coleman were said to be due to the addition of additional flocculant as it entered the tailings dam, rather than during transfer (at [150]). 341 In support of its contention that Mr Woolley's evidence established anticipation, SNF relied primarily on Professor Slatter's opinion that a process of flocculation and subsequent settling were sufficient to conclude that there was rigidification because, as he put it and as set out by the primary judge at [145], such a process 'must always result in rigidification'. That is, that there was no material difference between the process of settling and sedimentation and the process of rigidification. 342 The primary judge did not accept that contention and neither do I. Having rejected the contention that settling/sedimentation and rigidification were equivalent, her Honour said at [149] that 'if matters rested here, SNF would not have discharged its onus with respect to the Londonderry Mine'. Her Honour relied upon Dr Farrow's evidence as evidence of the worker skilled in the art. 343 The primary judge concluded that SNF had not established anticipation by reason of the acts at the Londonderry Mine. 344 SNF asks the Court to come to its own decision on the basis of Mr Woolley's evidence and the photographs that were in evidence before the primary judge. SNF asserts, but has not explained why, the primary judge was in error in relying upon and accepting the evidence of Dr Farrow as a person skilled in the art and, in particular, in relying on his conclusion that neither the evidence, the photographs nor the two together established that what was done was the process of claim 1 of Patent 944. SNF submits, in effect, that in accepting Dr Farrow's evidence, the primary judge's conclusions were inconsistent with her acceptance of the evidence of Messrs Woolley and Coleman. In particular, SNF points to the evidence that the tailings formed stacks. Mr Coleman also said that the stacks were compacted in a homogenous mass that could be walked over within six weeks, that the cracks in the deposits were 12 feet deep and that the material was, at least to the eye, very largely homogenous. 345 SNF submits that the primary judge was in error in preferring Dr Farrow's explanation of a chemical process which could not be directly observed or tested with respect to the prior use sites. It submits that Dr Farrow's evidence introduced an: …entirely unworkable standard of the concept of rigidification as "networking" which properly defies visual description (according to a description derived from the [Patents]), in particular when applied to the prior acts evidence, and can only be measured by scientific testing. This involves the application of criteria which are not disclosed by the specification or the claims in the [Patents], and such testing was clearly not done at, or in connection, with [the] Londonderry [Mine] (or other sites). 346 Ciba, in response, does not rely on the detailed explanation of networking nor upon a laboratory examination of homogenous stacks. Ciba contends that the evidence described the process of settling and not of rigidification. Professor Slatter agreed that that was the process described, not only in the Londonderry Mine but also in each of the other mining processes relied upon as prior use. 347 The primary judge understood the process described. Her Honour accepted Dr Farrow's description of that process and his understanding of the process depicted in the photographs. Her Honour concluded that the process was one of settling and not of rigidification. Once that distinction is accepted, which I have done, SNF has failed to establish anticipation by the process depicted at the Londonderry Mine.

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Beenup Mine 350 Mr Cigulev was a process metallurgist employed at the Beenup Mine from about June 1996 until June 1999. Mr Cigulev said that he decided to add flocculant to the tails slurry in a number of places in the waste stream in order 'to quickly settle the fines'. Mr Cigulev gave evidence that the previous process at the Beenup Mine involved the slow settling of clay and sand, which led to difficulties in recovering water. He explains that he introduced flocculant in an oil emulsion that was activated with water. The process resulted in stacks of the sand and clay that were so rigid as to stack rather than flow upon being deposited. The stacks rose in height forming a "volcano". 351 The primary judge accepted Mr Cigulev's evidence, which included the stage at which the flocculant was added and the fact that the flocculant was in an oil emulsion and was activated with water. The primary judge noted Professor Slatter's evidence that the process at the Beenup Mine resulted in settling and sedimentation. Her Honour also described Dr Farrow's evidence and, in particular, his explanation of the "volcanoes" referred to by Mr Cigulev. Dr Farrow concluded that there was no evidence that the stack formed at the Beenup Mine was a homogenous mixture of coarse and fine particles rather than a segregated stack. Dr Farrow also noted some other differences, in particular a second addition point for the flocculant as the tailings were discharged into the disposal area. His conclusion was that as the polymer was added on discharge, the coarse and fine fractions immediately segregated, causing a rapid build-up of stacks of coarse material. Dr Farrow noted that such a process was referred to, at page 3 of Patent 944, as relating to the problems associated with such deposition. Dr Farrow said that he did not consider the stacks to be rigidified (at [168]). 352 Her Honour accepted Dr Farrow's evidence and concluded at [171] that SNF had not discharged its onus of proof with respect to the process adopted at the Beenup Mine in that it had not established that the process was of improved rigidification, as in Patent 944. It followed that, in her Honour's view, the acts at the Beenup Mine did not constitute prior use and were not novelty defeating. 353 SNF submits that there was nothing in Mr Cigulev's evidence that suggested that the stacks were other than homogenous mixtures. Specifically, SNF draws attention to the fact that there is no requirement in the claims of Patent 944, apart from claim 4, for the rigidified material to be homogenous. SNF submits that 'there is nothing in the evidence of [Mr] Cigulev to show that rigidification in this sense was not present'. This, it seems to me, reverses the onus of proof. SNF also points out that Dr Farrow's evidence was merely an interpretation of what Mr Cigulev saw and observed, and should not have been preferred. The main point advanced by SNF is that Mr Cigulev's evidence demonstrates the existence of a process consisting of the integers of the claims of Patent 944 and that extraneous matters such as networking and homogeneity should have played no part in the assessment of anticipation. 354 The primary judge considered all of the evidence advanced as to the characterisation of the process of the Beenup Mine. This included not only the evidence of Mr Cigulev as to his use of polymers as flocculants, but also the evidence of Professor Slatter, who concluded that the process described by Mr Cigulev was of sedimentation and settling. While Professor Slatter viewed this as rigidification, her Honour did not agree. In my view, SNF has not established that the primary judge was in error in concluding that SNF had not discharged its onus of proof as to the existence of the integers of claim 1 of Patent 944. Her Honour found that a number of integers were not shown to have been present at the Beenup Mine. SNF has not established that those integers formed part of the process at the Beenup Mine. 355 In summary, in relation to the information arising from prior use at the Londonderry Mine, the Beenup Mine and the Bulga Mine, the primary judge set out the evidence presented and concluded that SNF had not discharged its onus of proof with respect to the processes there used. In particular, her Honour accepted the evidence of Dr Farrow, who identified integers in the claimed process that were either not present or that he could not see as present on the basis of the evidence advanced. Based on all of the evidence presented, which included extensive cross-examination, I am not satisfied that SNF has demonstrated any error in the primary judge's analysis.

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Innovative Step 356 SNF challenges her Honour's conclusion that it failed to make out its challenge to the validity of the Patents on the ground of lack of innovative step. 357 After setting out the applicable law, her Honour turned to consider the common general knowledge before the priority date. The primary judge pointed out at [184] that SNF accepted that none of the cited prior art documents had been shown to form any part of common general knowledge in Australia. Notwithstanding this, her Honour found that some matters of common general knowledge were clearly established, including the use of water-soluble polymers (including in high doses) as flocculants to dewater slurries of mining waste. Her Honour accepted that persons of skill in the art knew of the use of polymer as a flocculant added as powder in emulsions or aqueous solution. Her Honour also accepted that, as part of common general knowledge, persons of skill in the art in the industry would have been aware prior to the priority date that the flow properties of slurries are determined by mineralogy and water content of the slurry. Her Honour also accepted as common general knowledge, based on the evidence of industry witnesses, that: mining tailings could be disposed of by pumping the tailing slurry through a conduit to a disposal area where the material could be allowed to stand, with a view to land reclamation and water recycling; the addition of polymer as flocculant to a tailings slurry prior to, or during, pumping of the slurry to a disposal site enabled the slurry to thicken and dewater more effectively upon standing; tailing slurries dosed with polymers in this way could be deposited at a disposal site in which the material would settle and form sediments; and the higher the flocculant dose, the greater the flocculation. 358 Her Honour then turned to consider the application of s 7(4) of the Act. This section provides: For the purposes of this Act, an invention is to be taken to involve an innovative step when compared with the prior art base unless the invention would, to a person skilled in the relevant art, in the light of the common general knowledge as it existed in the patent area before the priority date of the relevant claim, only vary from the kinds of information set out in subsection (5) in ways that make no substantial contribution to the working of the invention. 359 Her Honour noted at [188] that, for the purposes of prior art information, SNF relied on the same prior art documents and acts on which it had relied for its novelty objection. 360 Ciba identified before the primary judge that, for the purposes of s 7(4) of the Act, there were three relevant variations between the prior art documents/acts and the claimed invention: 1. settling as opposed to rigidification; 2. whether the polymer is combined with the slurry material in the form of an aqueous solution; and 3. whether the flocculant is added to the slurry material between the thickener and the deposition area. 361 With respect to Slatter 3, the primary judge accepted Dr Farrow's evidence that adding the flocculant polymer to the slurry in the form of an aqueous solution makes a difference to the process. Her Honour concluded from the evidence that a person skilled in the art, in the light of common general knowledge before the priority date, would have considered the form in which the flocculant was added to have an important effect on the process. The evidence was not, her Honour said at [197], that such a person would consider that the invention as claimed in each of the claims of Patent 944 only varied from Slatter 3 in a way or ways that made no substantial contribution to the working of the invention. 362 The primary judge noted at [198] that the test in s 7(4) was that an invention is taken to involve an innovative step unless a person skilled in the art, in the light of common general knowledge before the priority date, would reach the conclusion referred to in the provision. Her Honour concluded that as SNF had failed to discharge its onus of proof, the Patents have an innovative step when compared to the process of Slatter 3 (at [197]). 363 With respect to Slatter 4, her Honour noted that the argument about innovative step turned on the fact that the principal difference between Slatter 4 and the Patents was that Slatter 4 referred to the addition of polymer in oil emulsion form rather than in aqueous solution. The primary judge accepted Dr Farrow's evidence that the difference in the form of the polymer would have an important effect on the process. Accordingly, her Honour found that SNF had failed to discharge its onus of proof and, by virtue of s 7(4) of the Act, the Patents have an innovative step when compared to Slatter 4. 364 Her Honour also concluded that SNF had failed to discharge its onus of proof with respect to the other prior art documents and acts relied upon. The basis of her Honour's conclusions with respect to these forms of prior art information was that the invention so far as claimed is of improved rigidification and, as described in the specification, the process of the claims is different from the process of settling or sedimentation, which is a difference that makes a substantial contribution to the working of the invention. It followed that Patent 944 involves an innovative step over Slatter 10, Slatter 12, Slatter 13 and the prior acts at the Bulga Mine, the Beenup Mine and the Londonderry Mine. 365 SNF does not criticise the primary judge's identification of the relevant common general knowledge of the persons skilled in the art for the purposes of s 7(4) of the Act. However, it submits that her Honour erred in finding that the inventions as claimed did not lack in innovative step. SNF relies on the comparison to be made for the purposes of s 7(4) between the invention, so far as claimed in the claim, and each piece of prior art, considered separately. 366 In this regard, Slatter 10, Slatter 12, Slatter 13, the Londonderry Mine, the Bulga Mine and the Beenup Mine do not need to be considered further, as SNF's submissions depend upon a finding in respect of those prior acts and publications that the term rigidification, as used in Patent 944, included the processes of settling and sedimentation. I have rejected this submission, as did the primary judge. 367 The comparison in s 7(4) is to be made from the perspective of the person skilled in the art in the light of common general knowledge in Australia before the priority date. It is then necessary to ascertain the nature of that difference and whether it makes a substantial contribution to the working of the invention (Dura-Post (Aust) Pty Ltd v Delnorth Pty Ltd (2009) 177 FCR 239 at [74]). Both parties submit that Delnorth, from which an application for special leave was refused, was correctly decided and that the primary judge correctly identified the relevant inquiry. 368 As Ciba submits, s 7(4) of the Act does not require the patentee to state the innovative step in the specification. The test, as stated in Delnorth, is whether the person skilled in the art in the light of common general knowledge would conclude that the invention only varied from the prior art in ways that made no substantial contribution to the working of the invention. As the primary judge observed, the onus for establishing a lack of innovative step rests upon the party challenging validity (cf. Firebelt Pty Ltd v Brambles Australia Ltd (2002) (2002) 188 ALR 280 at [31] in discussing s 7(2) of the Act). 369 Ciba submits that the advantages of rigidification over settling and sedimentation have been described by the primary judge and dealt with in the evidence. Ciba submits that the process of improved rigidification as claimed in the Patent clearly makes a substantial contribution to the working of the invention over the process of settling and sedimentation disclosed in the prior art. On that basis, Ciba submits, the Patent involves an innovative step over Slatter 10, 12 and 13 and the prior acts at Bulga, Beenup and Londonderry. 370 In essence, SNF submits that there was simply no advance in Patent 944, as previous patents had referred to the process of claim 1 as being an achievable result. 371 I now turn to consider the application of s 7(4) to the remaining relevant pieces of prior art.

[83]

Slatter 4 374 SNF says that there was nothing in Patent 944 to indicate an advantage in the use of polymers in aqueous solutions over the use of polymers in emulsion and submits that the primary judge erred in then not finding that, as a result of this, there was a lack of innovative step over Slatter 4. 375 This submission involves a misconstruction of s 7(4) of the Act. Section 18(1A) of the Act provides that, relevantly: An invention is a patentable invention for the purposes of an innovation patent if the invention, so far as claimed in any claim: (b) when compared with the prior art base as it existed before the priority date of that claim: … (ii) involves an innovative step. 376 As the primary judge stated at [177], s 7(4) of the Act provides that, in determining the issue of innovative step, the Court must ascertain: (a) the invention "so far as claimed in any claim"; (b) the person skilled in the relevant art; (c) the common general knowledge of the person skilled in the art as it existed in Australia before the priority date; and (d) whether, when considered from the perspective of a person skilled in the art, in the light of that common general knowledge, the invention as claimed only varied from the kinds of information in s 7(5) - here the cited prior art information - in ways that make no substantial contribution to the working of the invention as claimed. 377 Her Honour proceeded to consider each of those matters. It is apparent from s 7(4) that the onus is on the person seeking to establish an absence of innovative step and that that is established by the person of skill in the art armed with common general knowledge. It is not established by consideration of whether or not an innovative step is set out in the specification and claims of the patent under examination. 378 The primary judge noted that Professor Farrow's evidence was that the claimed process was different to that of Slatter 4 and that that difference would have an important effect on the process. Her Honour found that SNF failed to discharge its onus of proof to demonstrate that the invention as claimed only varied from Slatter 4 in ways that made no substantial contribution to the working of the invention. 379 SNF have not demonstrated any error in the approach taken by the primary judge or any error in her Honour's conclusions based on the evidence before her.

[84]

Sufficiency of Description 380 As the primary judge noted at [225], s 40(2)(a) of the Act provides that a complete specification must describe the invention fully, including the best method known to the patentee of performing the invention. SNF's complaints with regards to sufficiency were identified by the primary judge as, essentially, concerning the dosage and rate of addition of polymer and how the dosing point is to be identified so as to minimise shearing. 381 The primary judge cited the test as set out by the High Court in Kimberly-Clark Australia Pty Ltd v Arico Trading International Pty Ltd (2000) 207 CLR 1. Specifically, sufficiency is determined upon a consideration of the complete specification including the body and the claims, read as a whole, and the specification is sufficient if the skilled addressee would be enabled by the contents of the specification to produce something within each claim without new invention or addition or prolonged study of matters presenting initial difficulty (Lockwood Security Products Pty Ltd v Doric Products Pty Ltd (2004) 217 CLR 274 at [49], [60] and [103]). A specification is not insufficient merely because some experiment of a routine character is necessary in the particular case (Kimberly-Clark at [24]-[25]). 382 It is not suggested that the primary judge misstated, nor did SNF dispute, the basic principles set out by her Honour at [230]-[234]. 383 After considering the evidence, including: that of Dr Farrow, who expressed the view that 'practically skilled persons in the industry, such as SNF and the potential customers and industry members who were recipients of those SNF materials' would readily understand and be able to implement the processes, examples and descriptions used in the Patents (at [247]); that none of SNF's witnesses said they had any difficulty with the implementation of the SNF Process, itself an example of the claimed invention; and that it was part of the skill in the art to conduct experiments in the nature of trial and error to ascertain for example the optimum dosing point and flocculant dose to optimise the process; the primary judge concluded that Dr Farrow's evidence was supported by practically skilled persons in the industry. The primary judge concluded at [260] that SNF had failed to establish, on the balance of probabilities, that the disclosures in the Patents were not sufficient to enable the skilled addressee (in the light of common general knowledge at the priority date) to produce something within each claim without new inventions or additions. Her Honour said that the tests that such persons would need to carry out were no more than routine or standard tests that they would ordinarily carry out in the course of their work in the field and that those tests required neither invention nor ingenuity (at [260]). 384 SNF submits that the primary judge failed to take into account a number of matters in finding that a skilled addressee would have had to do no more than "routine trial and error". Accepting, for the purposes of the argument on sufficiency, that the relevant area of work which was routine before the priority date was a process concerned with settling and sedimentation, SNF says that the skills that were exercised in the field provide no evidence of the capacity of the individuals concerned to achieve the outcomes claimed in the Patents with respect to rigidification. SNF points to the evidence from Mr Bembrick that, it says, suggests that more than regular trial and error was involved. For example, $100,000 in capital costs were expended in the pilot trial. 385 SNF submits that the detailed criticisms of the various slump tests referred to in Patent 944 as described by Professor Slatter were not addressed by Dr Farrow and that Professor Slatter was not relevantly cross-examined. Nor were these criticisms, SNF says, addressed by the primary judge. As SNF put it in its written submissions: Ultimately, the point remains that, on the construction of the term "rigidification" applied by the trial judge (following the interpretation of Dr Farrow), it is impossible to identify from the reading of the specifications how rigidification, let alone improved rigidification, is achieved by the skilled addressee following the teaching contained therein. SNF points to the theoretical basis for the process set out by Dr Farrow, the networked structure, and points out that a person in the field would not know when a networked structure had been achieved, as distinct from the structure that results from settling and sedimentation. 386 Ciba's response is straightforward. It says that SNF's case at trial extended beyond the pleaded case, which identified a failure in the specification to identify the dosage and rate of addition of polymer and how the dosing point is to be identified so as to minimise shearing. That is, Ciba says, the case as pleaded alleged that Patent 944 does not teach the reader what to do to get the improved rigidification of the claims. 387 Ciba relies upon the evidence of Mr Schroeter and the findings of the primary judge that skilled addressees routinely undertook test work in order to optimise aspects of the claimed process, such as identifying the appropriate flocculant for a given situation, the physical conditions in which the flocculant was being applied, the type of equipment that was being used and the outcome that the customer was looking for from the application of the flocculant. Then, following standard laboratory tests, typically the technical sales representative would undertake a plant trial to see what happened. Once the flocculant had been chosen, the skilled person had to determine where the flocculant would be added in relation to the particular layout of the plant. This involves an element of trial and error to the extent that, as Ciba put it and as stated by Mr Schroeter, the skilled person 'would put some in and… would see how it ran… would look at what was coming out of the pipe'. 388 This evidence was accepted by the primary judge and formed the basis for her Honour's conclusion. Ciba submits that, on the basis of the evidence, the primary judge was correct to reject SNF's assertions concerning sufficiency and that SNF did not discharge the onus to establish lack of sufficiency. 389 I see no error on the part of the primary judge in accepting and relying on the evidence from the skilled witnesses, who talked of the nature and extent of routine trial and error carried out in the performance of processes such as the process of the claims of the Patent. I see no error in her Honour's conclusion that SNF failed to establish that the disclosures of Patent 944 were not sufficient to enable the skilled addressee to produce something within each claim without new inventions or additions.

SNF (Australia) Pty Ltd v Ciba Specialty Chemicals Water Treatments Limited

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Judgment (86 paragraphs)

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Cases Cited (22)

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