Infringement of Claim 4
77 The issue is whether the Fresenius system with the biBag as the vessel infringes claim 4.
78 Claim 4 of the patent is:
'A system for preparing a dialysis or replacement fluid or a component fluid thereof by mixing of at least one concentrate in powder form with water, said system comprising:
a source of water;
a vessel containing a powder concentrate, said vessel including an inlet at the top thereof and an outlet at the bottom thereof;
first fluid conducting means having a first end communicating with said source of water for withdrawing water from said source of water, and a second end for delivering a prepared fluid;
second fluid conducting means communicating with said source of water and with said inlet of said vessel for introducing water from said source of water into the top of said vessel, whereby a concentrate solution containing dissolved powder concentrate in water is produced in the vessel; and;
third fluid conducting means communicating said outlet of said vessel with a mixing point located in said first fluid conducting means intermediate said first and second ends for conducting said concentrate solution from the bottom of said vessel into said first fluid conducting means where it is mixed with fluid being conducted through said first fluid conducting means to thereby produce the prepared fluid, wherein the system is arranged such that a relatively constant concentration level of dissolved powder concentrate is maintained is said third fluid conducting means by fluid being conducted through said vessel from its top to its bottom.'
79 The primary judge accurately observed at [150] in respect of the biBag:
'There is no hole or aperture in the biBag at the bottom. Rather, a tube inside the vessel, with a filter at its end at the bottom of the vessel draws fluid from the bottom of the vessel and takes it to the intermediate annulated ring at the top of the vessel.'
80 The primary judge noted the definitions of outlet as 'an opening or passage by which anything is let out, a vent or exit' (Macquarie Dictionary) or 'an opening by which something escapes or is released; a means of issue or exit' (New Shorter Oxford (1993)). His Honour recognised that there is no opening of the vessel at the bottom of the vessel. However, his Honour accepted that the third fluid conducting means included the tube that is in the Fresenius biBag and that the concentrate enters the third fluid conducting means at the bottom of the vessel but inside the vessel. He acknowledged that, looking at the exhibit which is the biBag, 'one is tempted to view the outlet of the vessel as at the top of the vessel…because that is where the hole is which delivers the concentrate from inside the vessel to outside the vessel' at [155] (emphasis added). His Honour looked to the biBag as used, in operation and as part of the dialysis system. Viewed as part of the third fluid conducting means which begins on the internal side of the filter at the end of the tube at the bottom of the vessel, he concluded that there is an outlet at the bottom of the vessel into the third fluid conducting means.
81 In his Honour's analysis, the third fluid conducting means itself becomes the outlet, being the outlet for the fluid concentrate from the column and conducting it, internally in the vessel, from the bottom of the biBag to the top where it leaves the vessel. There is, however, no outlet from the vessel at the bottom. The primary judge relied on the evidence of Professor Schindhelm who saw the tube in the biBag as part of the third fluid conducting means and who saw no functional difference in part of the third fluid conducting means being inside the vessel from an aperture at the bottom of the vessel. His Honour concluded:
'Examining the matter functionally, the fluid concentrate leaves the powder column and the vessel at the point it passes through the filter into the third fluid conducting means at the bottom of the vessel. In this sense, though the vessel is not cut or pierced at the bottom, nevertheless there is an outlet at the bottom.'
82 Put simply, in the case of the biBag, the concentrate leaves the column at the bottom of the column, which is at the bottom of the vessel. The concentrate enters a tube (the third fluid conducting means) which does not exit the vessel at the bottom thereof but conducts the concentrate to an opening at the top of the vessel. Acknowledging at [158] that the biBag is not cut or pierced at the bottom, his Honour viewed the matter 'functionally' and said: '[i]n this sense, though the vessel is not cut or pierced at the bottom, nevertheless there is an outlet at the bottom'. Looking at the claim "purposively" his Honour found at [159] that the 'precise location of the break in the skin of the vessel through which the fluid passes into the intermediate ring and continues along the third fluid conducting means in functionally immaterial'. The conclusion was that "what is taught by the claims, read in the light of the specification' is that the outlet of the vessel is where the concentrate enters the third fluid conducting means and thereby exits the vessel and that point of exit is at the bottom of the vessel.
83 His Honour found that there was no functional advantage obtained by running the tube inside the bag up to the standard annulated fixture at the top. He concluded that the substantial idea disclosed by the body of the specification and made the subject of the claim 4 has been taken and embodied by the respondent in the biBag: (Radiation Limited at 51; Populin at 41; Bartlem Pty Ltd v Cox Industries (Aust) Pty Ltd (2002) 55 IPR 449, 477-78 [59]).
84 It is the case that each of the claims under consideration, including claim 2 and claim 4 commence with the words '[a] system for preparing a dialysis or replacement fluid or a component fluid thereof by mixing of at least one concentrate in powder form with water, said system comprising…'. However, there is a need to consider each claim as drafted by the patentee, in the context of the specification and to recognise that there are a series of claims, dealing with different aspects of the invention. Each claim seeks to define an aspect of the invention and the monopoly sought. In considering claim 2, his Honour recognised that it was a separate claim dealing with one aspect of the invention and that, while the system as claimed in the claim was "fed" into a larger system for dialysis, it had to be considered in its own terms. The same can be said for claim 4.
85 Relevant to the consideration of infringement of claim 4 are the words: 'a vessel containing a powder concentrate, said vessel including an inlet at the top thereof and an outlet at the bottom thereof.' (emphasis added) This clearly refers to the vessel itself. The claim clarifies the matter further. The second fluid conducting means communicates with the source of water and with 'said inlet of said vessel'. The third fluid conducting means communicates 'said outlet of said vessel' with a mixing point. The third fluid conducting means conducts said concentrate solution 'from the bottom of said vessel' into the first fluid conducting means. The fluid is conducted through the vessel 'from its top to its bottom'.
86 The primary judge's analysis looks to where, functionally, the concentrate solution leaves the vessel, in that it enters the third fluid conducting means which itself has an entry at the bottom of the vessel. The claim, on the other hand, speaks of a vessel containing a powder concentrate with an inlet at the top of the vessel and an outlet at the bottom of the vessel. The third fluid conducting means of the claim communicates the outlet of the vessel with a mixing point in the first fluid conducting means.
87 As part of his reasoning of the construction of claim 4, His Honour reiterated the 'essential integer' of the use of the powder in a vessel and dissolution of it by water on-line, which does not appear in the words of the claim. Fundamental to his Honour's reasons on this aspect was the lack of functional advantage of the biBag over the vessel of claim 4. Fresenius disputes that absence of functional difference but that is not to the point. Functionally, his Honour relied upon 'what is taught by' the claims, read in the light of the specification, rather than what is defined by the claims (s 40(2)(b) of the Act). If the description of the vessel as having an inlet at the top and an outlet at the bottom were an inessential integer of the claim, functional equivalence would be relevant to infringement. However, there is no infringement if an essential integer is replaced by a mechanical equivalent. As pointed out in Blanco-White 4th edition at 2-208, to characterise a feature set out in the claim as not an essential feature of that which is claimed and consequently to disregard it in determining the scope of the claim, is rare. The question whether differences in construction of the biBag are material to functionality is not relevant (Walker v Alemite Corporation (1933) 49 CLR 643 at 657; Bartlem at [84])
88 As was said by Lord Parker in Fellows v Thomas William Lench Ltd (1917) 34 RPC 454 at 55 and adopted by Dixon J in Walker v Alemite at 656, there may be reasons for the scope of a claim known to the inventor but not to the court.
89 Dixon J continued at 657:
'The question is not whether the differences of construction in the respondent's nipple and in that of the appellant are material to the utility of the appliance or to the manner of performing its function or whether ingenuity is involved in the changes. The question is: How wide is the monopoly? Once it is determined that the discarded features are essential to the claim, the substitution of other means of performing the like function cannot amount to infringement by colourable variation, or by the use of a mere mechanical equivalent. The changes are not insubstantial variations in detail under colour of which the thing claimed is taken. They are not other mechanical embodiments of the inventive idea for which protection has been obtained. The claim itself makes them cardinal. The intention of the appellant to take advantage of the narrowness of the monopoly is, of course, immaterial.'
90 In Azuko Pty Ltd v Old Digger Pty Ltd (2001) 52 IPR 75, while there was a difference of opinion on the construction of the claim under consideration, both Heerey J in dissent (at [77] and [83]) and Gyles J (at [157]) confirmed that once an essential integer or feature is missing, the question of functional significance is irrelevant.
91 This is not a case where the scope of the claim can, by the purposive construction of a word, be expanded to include the allegedly infringing article. The application of purposive construction has recently been considered in Sachtler at [42] - [44], [46] - [56], [62] and at [114]. As discussed in Sachtler, previous cases in Australia (such as Populin) and the United Kingdom (such as Catnic) stand for the proposition that the essential integers are determined by a common sense assessment of what the words of the claims convey in the context of then-existing published knowledge. So-called 'purposive construction' does not propound a novel principle.
92 One does not look to see whether the allegedly infringing article is the same in substance and effect as the disclosures of the specification or of the claims. The principle of "pith and marrow" applies to immaterial variations where an inessential part or step is omitted or substituted. There is no infringement if a variant has a material effect on the way the invention works (Sachtler at [51]-[52]). However, this does not mean that there is infringement where there has been no taking of all the essential integers of the claim (Olin at 246 per Gibbs J). The form and wording of the claim are determinative.
93 As Gyles J said in Grove Hill at [311] 'a patentee cannot eat the cake and have it too by persuading a court to construe a claim more widely than the patentee was prepared to risk when framing the claims under the guise of purposive construction'.
94 The whole of the specification must be read in order to construe the claim. So much is not in dispute. However, that does not mean that the words of the claim are to be ignored. Nor can it be ignored that the patentee has chosen not to include in a claim matters, integers or aspects of the invention that have been referred to in the body of the specification. This accords with the well-accepted principle enunciated in Welch Perrin at 610 that glosses drawn from the body of the specification cannot be used to narrow or expand the boundaries of the monopoly as fixed by the words of a claim.
95 In our view, the primary judge was in error in looking to what was "taught" by the claims, rather than what was claimed. To our mind, his Honour impermissibly construed the claim with an eye to the allegedly infringing article.
96 The vessel as identified in claim 4 is an item that is a discrete component of the system with which the third fluid conducting means communicates. The claim requires that the vessel and communicating means be distinct. The third fluid conducting means must communicate with the vessel. There must be an outlet from the vessel and that outlet must be at the bottom of the vessel.
97 His Honour focussed on the words requiring the outlet to be "at the bottom" of the vessel and construed them to require simply a physical location at the bottom of the vessel but not an outlet from the vessel at the bottom thereof. This ignores the words later in the claim requiring the third fluid conduction means to communicate the said outlet of the said vessel with a mixing point.
98 These are clearly made essential by the patentee in the claim.
99 The words of the claim, when the whole of the claim is considered, are clear: the outlet is an outlet of the vessel. That is, there must be an opening in the vessel itself at the bottom of it. That is a clear essential integer of claim 4. Further, the body of the specification envisages a system where the concentrate fluid is conducted from the top to the bottom of the column in the vessel or, alternatively, from the bottom to the top. The opening at the bottom of the vessel, at the bottom of the column, permits the exit of fluid from the column to the third fluid conducting means. The third fluid conducting means is not the outlet, it communicates or connects the outlet with a mixing point and conducts the concentrate solution from the bottom of the vessel.
100 When the claim is read in the light of the specification as a whole, including the figures, there can be no doubt that the outlet of the claim is an outlet both located at the bottom of the vessel and an outlet from the vessel. For example, at page 17 in the specification, lines 17-30 there is described a 'powder concentrate columns or vessels' in the form of a cartridge with penetrable membranes 'at its upper inlet and its lower outlet which are adapted to be penetrated by suitable connection devices'. At page 25, lines 20 to 23, there is reference to the vessel which includes 'an inlet at the top thereof and an outlet of the bottom thereof' (emphasis added).
101 This interpretation and requirement is also reinforced by the figures in the patent. Each of the figures shows a vessel with an outlet of the vessel at the bottom of the vessel. There is no suggestion in the specification of a vessel with other than an outlet from the bottom of the vessel.
102 By looking at the functionality of the biBag, rather than the clear wording of the claim, as supported by the specification, his Honour has substituted a mechanical equivalent of an essential integer of the claim. This is not permissible for the purposes of ascertaining novelty or infringement. The patentee has, by the wording of the claim to an apparatus, left open the design of the biBag.
103 The words of Dixon J in Radiation Limited, cited in [66] are apposite. Put another way by Aickin J in 3M at 286, a defendant cannot take the substance of the invention unless the wording of the claim makes it clear that the relevant area has been deliberately left outside the claim. Then, if the substantial idea is taken in a way so left open, there is no infringement. That is the case here.
104 If claim 4 is construed in a commonsense or "purposive" manner, in the sense properly envisaged in Catnic and Populin (see Sachtler), it is apparent that 'an opening at the bottom of the vessel' means an opening of the vessel at the bottom thereof. In looking to a "purposive" construction of the claim his Honour seems to have overemphasised the substantial idea disclosed in the body of the specification and effectively disregarded the words of claim 4.
105 As in Populin, the Fresenius system uses a good deal of the concept of the Gambro invention. However, the requirement for the vessel itself to have an inlet at the top and an outlet at the bottom is an essential feature of the claim. This is apparent, not only from the wording of the whole of the claim to the apparatus but also from the specification and the figures.
106 The Fresenius system with the biBag does not infringe claim 4.