Melbourne v Terry Fluid Controls Pty Ltd
[1994] FCA 134
•11 MARCH 1994
JOHN STANLEY MELBOURNE v. TERRY FLUID CONTROLS PTY LIMITED
No. VG283 of 1993
FED No. 134/94
Number of pages - 16
Patents
(1994) AIPC 91-058
COURT
IN THE FEDERAL COURT OF AUSTRALIA
VICTORIA DISTRICT REGISTRY
GENERAL DIVISION
NORTHROP, GUMMOW AND OLNEY JJ
CATCHWORDS
Patents - construction of claims - narrowing of claim to accord with general expectation of those skilled in the art - whether permissible - validity - novelty.
Patents Act 1952, ss. 40, 100
Meyers Taylor Pty Ltd v Vicarr Industries Ltd (1977) 137 CLR 228
Minnesota Mining and Manufacturing Company v Beiersdorf (Australia) Ltd (1980) 144 CLR 253
Welch Perrin and Company Pty Ltd v Worrel (1961) 106 CLR 588
Norton and Gregory Ltd v Jacobs (1937) 54 RPC 271
Catnic Components Ltd v Hill and Smith Ltd (1982) RPC 183
Commonwealth Industrial Gases Ltd v MWA Holdings Pty Ltd (1970) 44 ALJR 385
Allsop Inc. v Bintang Ltd (1989) 15 IPR 686
HEARING
MELBOURNE, 7 and 8 March 1994
#DATE 11:3:1994
Counsel and solicitors Mr R. Macaw QC and
for the appellant: Mr M.T. Bevan-John
instructed by Galbally and O'Bryan.
Counsel and solicitors Dr J. Emmerson QC and
for the respondent: Mr G.S. Clarke
instructed by Garland Hawthorn Brahe.
ORDER
THE COURT ORDERS THAT:
(1) The appeal be dismissed.
(2) The appellant pay the costs of the respondent of the appeal.
Note: Settlement and entry of orders is dealt with by Order 36 of the Federal Court Rules.
JUDGE1
NORTHROP, GUMMOW AND OLNEY JJ The appellant is registered proprietor of Patent No. 584738 ("the Patent"). The Patent was granted pursuant to the Patents Act 1952 ("the 1952 Act"). The priority date of each of the claims of the complete specification is 14 January 1986. The complete specification is for an invention entitled "Air Cylinder Device".
By a proceeding commenced in this Court on 19 December 1989 the appellant sought relief in respect of alleged infringement by the respondent of the claims of the Patent.
By its cross-claim, the respondent alleged that each of the claims of the Patent was invalid, and sought an order that the Patent be revoked.
After a trial which extended over 12 days, the primary Judge ordered that the appellant's application be dismissed and that, on the cross-claim, the Patent be revoked. His Honour's judgment is reported (1993) 26 IPR 292.
The 1952 Act was repealed by s. 230 of the Patents Act 1990 ("the 1990 Act"). The 1990 Act commenced on 30 April 1991. In his judgment (26 IPR at 295) his Honour set out the legislation which produced the result that despite the repeal of the 1952 Act during the pendency of the proceeding, the 1952 Act continued to apply to the issues both of infringement and validity.
In the cross-claim, validity was attacked for inutility, want of novelty and obviousness. The provisional specification had been filed on 14 January 1986, and the complete specification on 2 September 1986. The respondent contended that the claims were not fairly based on matter described in the provisional specification with the result that validity was to be determined as at 2 September 1986. The interval between January and September 1986 was significant for the respondent's case because on one branch of the argument it alleged that one of the anticipations upon which it relied (the importation of what were called the SMC devices) took place within that period.
There was no allegation that any of the claims was invalid because it did not define the invention or was not clear and succinct, or otherwise did not comply with s. 40 of the 1952 Act.
The primary Judge held that the respondent failed in its attack on validity based upon inutility and obviousness. There is no appeal from these findings. However, the respondent succeeded in satisfying the primary Judge that the claims were not novel. Three particular anticipations had been relied upon by the respondent. The first was the manufacture and sale by the respondent in about 1983 of certain devices made in accordance with a drawing numbered 602. The second was the manufacture of a device by Alcan Australia Limited in accordance with a drawing dated 2 October 1985 ("the Festo drawing"). The third was the importation into Australia of certain equipment manufactured by a Japanese company known as "S.M.C.".
The primary Judge approached the issues of anticipation in a manner consistent with that explained by Aickin J in Meyers Taylor Pty Ltd v Vicarr Industries Ltd (1977) 137 CLR 228 at 235. That is to say, the basic test for anticipation is the same as that for infringement and generally one can properly ask whether, if the Patent were valid, the alleged anticipation would constitute an infringement.
The primary Judge held that in a device manufactured in accordance with the Festo drawing, an essential integer of the claims in the complete specification was lacking. The Festo drawing therefore was not an anticipation.
There was a debate as to whether the user of the S.M.C. equipment was a secret use within the meaning of sub-s. 100 (2) of the 1952 Act such that account was not to be taken of it for the purposes of the alleged anticipation. His Honour decided that the user had not been a secret use, but that the S.M.C. devices did not constitute an anticipation because not all the essential integers as claimed in the Patent were found therein.
However, the primary Judge held that devices manufactured in accordance with the 602 drawing were anticipations of the invention claimed by the appellant in his Patent. On this ground the cross-claim succeeded and the order for revocation was made. At the end of his judgment (26 IPR at 306) his Honour added:
"If the patent had not been revoked, its infringement would have been established. Proof was made of several infringements by the respondent. In his final address (counsel for the respondents) made no submission against a finding of those infringements."
On the appeal, the appellant seeks to have the orders made by the primary Judge set aside and in place thereof the appellant seeks injunctive relief and a certificate as to validity. An order is also sought for judgment for the appellant for damages to be assessed or, at his option, an account of profits. The making of such an order would require the matter to be remitted to a Judge of the Court for further directions for the taking of the account or the assessment of the damages.
By its notice of contention, the respondent supports the orders of the primary Judge but contends that the issue of anticipation should have been decided in its favour on a different construction of the claims to that given by the primary Judge. The respondent contends that if the claims were construed as it would have them, then there would still have been an anticipation by the 602 devices. It also submits that on the construction given by the primary Judge to claim 1, there was no evidence that the allegedly infringing cylinders achieved electrical isolation which would continue for the period required by that construction.
On the other hand, the appellant contends that the primary Judge correctly construed the claims but fell into error in then deciding that, on that construction, there was anticipation by the 602 devices. Rather, the appellant submits, the Court should have held that there was no anticipation by devices embodying the 602 drawing, because they had not been shown to provide electrical isolation over the necessary period. The significance of this requirement of durability of electrical isolation will appear later in these reasons.
Both sides accept that if the respondent be correct in the construction it would place upon the claims, then the 602 devices would be an anticipation.
The differing submissions as to construction are at the centre of the appeal. However, before turning to consider the issue of construction, we should indicate that in the alternative the respondent contends that the primary Judge should have held that a device made in accordance with the Festo drawing was an anticipation, and that he should have reached the same conclusion in respect of the S.M.C. devices. In relation to this last issue, the parties also are at odds as to questions of secret use and fair basing.
There are 9 claims for the invention. Claim 9 is a Raleigh Cycle claim, being for a device as in claim 1 "substantially as herein described with reference to (4 drawings)". Claims 2 - 8, as well as claim 9, are dependent upon claim 1. The attack on validity proceeded on the basis that if claim 1 fell, the other claims also fell. The relief sought in respect of infringement is directed to claim 1. Accordingly, both before the primary Judge and on appeal, the arguments focussed upon the construction and operation of claim 1.
Before turning to the text of claim 1, it is appropriate to set out the passages in the complete specification in which the inventor describes the problem or difficulty sought to be overcome by the invention. He states:
"This invention relates to an improved extendable cylinder device, such as an air cylinder. In particular the invention relates to such device for high temperature application, such as for use in extending and retracting a crust breaking implement for a molten salt electrolytic cell.
Air cylinder devices for actuating crust breaking implements must of necessity be of a robust, electrically insulated form. In one arrangement ends of a cylinder of the device are closed by respective end assemblies, with tie bolts extending along the exterior of the cylinder and projecting through the end assemblies being secured by retaining nuts threaded onto each projecting end of each tie bolt, such as disclosed in my copending application No. 57896/86. A piston of the device has a piston rod which projects through one end assembly and is pneumatically extendable and retractable for causing a crust breaking implement mounted on one end of the rod to be impacted against crust to be broken open. It is necessary that the piston be electrically isolated from the cylinder. However, particularly as the device is to operate under heavy mechanical loading at temperatures typically up to about 450oF, there is difficulty in providing a satisfactory arrangement for electrically isolating the piston. This difficulty is most pronounced at the end assembly of the cylinder from which the piston rod projects.
The invention provides a cylinder device for use as an actuator for a fused salt electrolytic cell crust breaking implement, the device having a cylinder in which a piston is slidable, a rod of the piston extending through an end assembly at one end of the cylinder, and an isolating arrangement within the end assembly by which the piston is electrically isolated from the cylinder. According to the invention, the isolating arrangement is provided within the one end assembly and defines a bore through which the piston rod extends. The isolating arrangement includes a sleeve which defines a substantial portion of the axial extent of the bore. The arrangement also includes, at an end of the bore from which the piston rod extends, an annular scraper member having an annular body and an annular scraper fin which projects radially inwardly from the body to slidably engage the surface of the piston rod. Intermediate the sleeve and scraper member, the arrangement further includes an annular air seal. The sleeve, the air seal and at least the body of the scraper member are formed from a suitable heat resistant, electrically non-conducting material.
A variety of materials can be used for the sleeve, air seal and body of the scraper member. However a glass filled PTFE preferably is used, at least for the sleeve, because of its further advantage of being a low friction material. The glass filling of the PTFE can be of fibre or fine glass beads or powder; the glass content most preferably ranging from 15 to 25%. Other thermoplastic polymer materials or polyphenyl sulphide can be used, at least for the sleeve. The end of the sleeve remote from the air seal and scraper member may simply abut a surface defined by the end assembly. This arrangement is preferred, since it enables the sleeve to be of a maximum axial extent and define a major portion of the bore. The sleeve then is best able to reduce wear of itself and other components of the isolating arrangement, as well as of the rod by providing greater support for the rod against heavy slide loadings in use."
The primary Judge found (26 IPR at 293-294) that the smelting of aluminium in fused salt electrolytic cells is carried on at several places in Australia. He said:
"The cell is a large steel pot lined with a composite of aluminium, steel, carbon and tar based products which is thermally and electrically insulated from the steel pot. In operation the pot contains molten sodium aluminium fluoride. In that molten cryolite are suspended pure carbon blocks, which constitute anodes of the cell when electric current of low voltage and high amperage is passed through them and through the molten electrolyte to the cathode lining of the pot. Aluminium oxide
(alumina) obtained from bauxite is fed into the cell in measured quantity every few minutes. The alumina particles are less than a millimetre in diameter and may be so small as to resemble talcum powder. The very high temperature of the molten electrolyte facilitates the reduction of the alumina to aluminium, the oxygen combining with the carbon of the anode to product carbon dioxide. The aluminium sinks to the cathode whence it is periodically siphoned from the pot. The smelting process is continuous. . . . A very hard crust of irregular configuration forms during smelting on the surface of the molten electrolyte. The crust-breaking implement which the patented cylinder actuates is a metal ram attached to the end of the piston rod of the air cylinder, which is suspended above the pot. The air cylinder extends the ram vertically down to cause it to break a hole in the crust, through which the measured quantity of alumina falls into the molten electrolyte, and then retracts the ram clear of the surface of the crust. . . . At the head end of the air cylinder which encloses the piston rod there is a need of:
(a) Effective sealing between the surface of the piston rod and its housing to prevent escape of air under higher than atmospheric pressure within the cylinder to the outside of the cylinder;
(b) Support and restraint of the piston rod in opposition to the lateral forces applied by the hard irregularly shaped crust to the ram which is attached to the piston rod;
(c) Effective wiping or scraping from the surface of the piston rod, of matter adhering to it and likely to wear the piston rod and to abrade or distort the air seals, as the rod is retracted and before the adherent matter makes contact with an air seal."
His Honour explained the object sought to be attained by the invention as follows (26 IPR at 294):
"There are two principal obstacles to the satisfaction of those needs: high temperatures and electric current flowing from the electrolytic cell up the metallic ram and the attached metallic piston rod when the ram plunges into the molten cryolite. If the current flows from any part of the piston assembly to the metallic cylinder there is, or should be, yet an insulation by which the flow of current to earth is prevented. The structure supporting the anodes and the crust breaking apparatus and any point feeder not integral with that apparatus is electrically isolated from the crust-breaking apparatus by insulating material at the bolt connections between the supporting structure and those other structures. But the material wears and at times fails. Experience had shown the need for, and the specifications of aluminium smelter proprietors required, electrical isolation of the piston from the cylinder. Contact might occur between the head of the piston and the inner surface of the cylinder, and between the under-side of the head of the piston and the end assembly of the cylinder through which the piston rod projects when the rod is fully extended. Against the flow of current at those points of contact electrically-insulating material could be interposed. But contact between, or electrical arcing over the very small spaces separating, the piston rod and that part of the end assembly through which the piston rod was extended and retracted created difficulties which it was the patentee's object to overcome." (Emphasis supplied)
It is convenient now to turn to claim 1. It is for a combination in the sense of that term given by Aickin J in Minnesota Mining and Manufacturing Company v Beiersdorf (Australia) Ltd (1980) 144 CLR 253 at 266. That is to say, it combines a number of elements or integers which interact with each other to produce a new result. It is the interaction which is the essential requirement. Each of the integers may be old or some of them may be new.
Claim 1 states:
"A cylinder device for use as an actuator for a fused salt electrolytic cell crust breaking implement, the device having a cylinder in which a piston is slidable, a rod of the piston extending through an end assembly at one end of the cylinder, and an isolating arrangement within the end assembly by which the piston is electrically isolated from the cylinder; the isolating arrangement being provided within the one end assembly and defining a bore through which the piston rod extends, the isolating arrangement including a sleeve which defines a substantial portion of the axial extent of the bore, and an annular scraper member at an end of the bore from which the piston rod extends, the scraper member having an annular body and an annular scraper fin which projects radially inward from the body to slidably engage the surface of the piston rod, the arrangement further including an annular air seal intermediate the sleeve and scraper member; the sleeve, the air seal and at least the body of the scraper member being formed from a suitable heat resistant, electrically non-conducting material."
(Emphasis supplied)
The dispute as to the construction of claim 1 centres upon the passage "an isolating arrangement within the end assembly by which the piston is electrically isolated from the cylinder". It was necessary to determine that for which a monopoly is claimed before proceeding to consider objections to the validity of claim 1: Welch Perrin and Company Pty Ltd v Worrel (1961) 106 CLR 588 at 609. A difficulty in the present case is that the primary Judge placed what, in the event, is the crucial construction upon claim 1 only in the course of considering the objection to validity based upon the prior publication of the 602 devices.
The primary Judge referred to the harsh conditions in which an air cylinder for use in actuating a crust breaking implement in an alumina smelting pot must operate. His Honour said that there was expert evidence that the electrical isolation of the piston rod from the cylinder of a device manufactured in accordance with the 602 drawing "would not long continue". He then (26 IPR at 299) referred to the submission of counsel for the respondent:
". . . that no period of time during which electrical isolation would continue was claimed in any of the claims and that the absence of an integer of any of the claims is not shown by showing that the period during which isolation continues is short."
The primary Judge went on to give a construction to claim 1 which had the result that devices manufactured in accordance with the 602 drawing anticipated the invention claimed in the Patent.
The crucial passage in the judgment is as follows (26 IPR at 300):
"I think that the electrical isolation to which the claims refer is to be construed as such an isolation as will continue in use of the device for a period longer than a few months. But in the conditions of use prevailing in aluminium smelter potlines a brief life for some of a batch of air cylinders installed at about the same time can be expected, as I find. If some of the devices continue in use for years under those conditions, as I find that some of them did, the device falls, in my opinion, within the meaning of the phrase '(a) cylinder device . . . having . . . an isolating arrangement . . . by which the piston is electrically isolated from the cylinder" in claim 1. I accept (counsel for the respondent's) submission that none of the claims defines the device by reference to any promised period of use, or to any promised period of electrical isolation, so that only a period which matched the general expectation of those skilled in the art could be implied. The whole of the evidence suggested that that expectation was of a period not ordinarily exceeding the 18 months stated by Mr Van Acker, and often falling well short of 18 months." (Emphasis supplied)
The primary submission of the respondent, on its notice of contention, is that claim 1 states no criterion of durability and that the primary Judge erred in holding that the required electrical isolation within the meaning of claim 1 means electrical isolation which will continue during the use of the claimed cylinder device "for a period longer than a few months". The respondent further submits that its case for anticipation is made good whether or not the 602 device had electrical isolation which would continue during use for a period of longer than a few months.
In the course of dismissing the objection based on alleged inutility (a finding from which, as we have indicated, there is no appeal) the primary Judge resolved an alleged ambiguity in claim 1 by recourse to the body of the specification (26 IPR at 296). If an expression in a claim is not clear then it is permissible to resort to the body of the specification to define or clarify the meaning of words used in the claim: Interlego AG v Toltoys Pty Ltd (1973) 130 CLR 461 at 479, per Barwick CJ, Mason J.
But whilst this may be consistent with the course pursued by the primary Judge in dealing with the objection alleging inutility, in construing claim 1 as he did his Honour did not rely upon any passages in the complete specification. He went outside it, apparently to the general expectation of those in the art as to a reasonable period of durability. This was a more extreme step than that discussed in Interlego. Counsel for the appellant did not direct us to any portion of the body of the specification which dealt with durability of the electrical isolation.
Certainly the specification is to be construed in the light of the common knowledge in the art before the priority date: Welch Perrin, supra at 610. But as is pointed out by Dixon CJ, Kitto and Windeyer JJ in the same passage, it is not permissible to vary or qualify the plain and unambiguous meaning of a claim by reference to the body of the specification. Nor is it permissible to limit or expand a claim by language in the body of the specification appropriate to a subject matter narrower or broader than that comprehended by the claim: Sunbeam Corporation v Morphy-Richards (Australia) Pty Ltd (1961) 35 ALJR 212 at 220, per Windeyer J. In our view, still less is it permissible to imply a limitation upon a claim so as to match what is said to be the general expectation of those skilled in the art.
In Norton and Gregory Ltd v Jacobs (1937) 54 RPC 271, the English Court of Appeal dismissed an appeal from a holding that the patent in suit was bad for want of utility. When construed according to their natural meaning, the claims included substances which were undesirable and ineffective for producing the result sought by the patentee. Sir Wilfrid Greene M.R., at 276-277, said:
"Now if Claim 1 be read by itself and construed in accordance with the ordinary meaning of the language used, it is apparent that the use of any reducing agent falls within it. The character of the reducing agent to be used is not defined by reference to any particular quality or any particular result. If the matter stood there, the Claim would be unquestionably bad. But it is said . . . that the language of the Claim must be construed so as to exclude any reducing agent which a chemist of ordinary skill would know, with or without experiment, to be unsuitable in view of the result to be achieved. We are unable to accept this argument. The fact that a skilled chemist desiring to use the invention would reject certain reducing agents as being unsuitable is one thing; it is quite a different thing to say that a claim must in point of construction be cut down so as to exclude those reducing agents because a skilled chemist would not use them. To adopt the latter proposition would not be to construe the Specification but to amend it, and it would, in our opinion, be mere self-deception to hold otherwise. The duty of a patentee is to formulate his claim in such a way as to define with clarity the area of his monopoly; the claim is the solemn operative part of the Specification in which the patentee sets himself to achieve that purpose, and in construing it, it is of great importance not to lose sight of that fact. It is illegitimate to whittle away clear words in a claim by reading into them glosses and limitations extracted from the body of the Specification whose function is in its essence different from that of the claim. Each part of the document must be construed in the light of the function with is peculiarly its own. In the same way it is in our opinion illegitimate to whittle away the clear words of the claim - selected, as they must be taken to be, with the peculiar function of the claim in mind - by writing into them glosses and limitations based on the fact that a skilled chemist would avoid working in part of the area which the words in their ordinary meaning are wide enough to include. This does not mean that regard is not to be paid to the fact that the claim as well as the body of the Specification is addressed to persons skilled in the art and must be construed accordingly. But the argument here goes far beyond this and, under the pretence of construing the claim, in reality seeks to reform it."
This passage was approved and applied by Menzies J in Welch Perrin, supra at 601.
Moreover, if claim 1 were to be read in the manner which commended itself to the primary Judge by implying a criterion of durability, the result might well be to put the claim at risk of attack under s. 40 of the 1952 Act for ambiguity. It is true that lack of precise definition is not fatal to the validity of a claim so long as it provides a "workable standard" which is suitable for the intended use: Minnesota Mining and Manufacturing Company v Beiersdorf (Australia) Ltd, supra at 274. Nevertheless, the standard of durability propounded in the judgment under appeal is inherently lacking in clarity. We have set out the crucial passage earlier in these reasons. The claim is said to be for an apparatus with the result that electrical isolation will continue in use of the device for a period "longer than a few months". Then it is accepted that only a period which matched the general expectation of those skilled in the art could be implied. Finally, that general expectation is then found to be one not ordinarily exceeding 18 months and often falling well short of 18 months.
The invention consists of the combination of integers to form a sealing arrangement which prevents the escape of air pressure from within the cylinder and electrically isolates the piston rod from the end assembly. Claim 1 is defined by result but without any further gloss that the result must endure for a period equal to the expected life of other components of the cylinder device.
If claim 1 be read according to its ordinary meaning and without it being narrowed by the implication found by the primary Judge, then it is accepted that the 602 device was an effective anticipation.
However, the appellant sought to avoid this result by relying upon what it was submitted flowed from the speech of Lord Diplock in Catnic Components Ltd v Hill and Smith Ltd (1982) RPC 183 at 242-243. His Lordship there said:
"My Lords, a patent specification is a unilateral statement by the patentee, in words of his own choosing, addressed to those likely to have a practical interest in the subject matter of his invention (i.e. 'skilled in the art'), by which he informs them what he claims to be the essential features of the new product or process for which the letters patent grant him a monopoly. It is those novel features only that he claims to be essential that constitute the so-called 'pith and marrow' of the claim. A patent specification should be given a purposive construction rather than a purely literal one derived from applying to it the kind of meticulous verbal analysis in which lawyers are too often tempted by their training to indulge. The question in each case is: whether persons with practical knowledge and experience of the kind of work in which the invention was intended to be used, would understand that strict compliance with a particular descriptive word or phrase appearing in a claim was intended by the patentee to be an essential requirement of the invention so that any variant would fall outside the monopoly claimed, even though it could have no material effect upon the way the invention worked."
It is important to appreciate that this passage appears in a judgment in which what was at issue was not invalidity but an alleged infringement. The patent was in respect of steel lintels and claim 1 required that the rear member should "extend vertically". After the institution of a proceeding for infringement, the defendants produced a second form of lintel which, instead of being perpendicular to the base, was inclined at 6 or 8 degrees from the vertical. This departure had a negligible effect upon function.
In accordance with authority in Australia, what the defendants had done might well have been interpreted as an unsuccessful attempt to avoid trespass upon the literal meaning of the claim by a modification so small as to be insignificant and to have no material effect upon the way in which the invention, as claimed, worked: see Commonwealth Industrial Gases Ltd v MWA Holdings Pty Ltd (1970) 44 ALJR 385 at 388, Rehm Pty Ltd v Websters Security Systems (International) Pty Ltd (1988) 81 ALR 79 at 91-92. In Catnic, supra at 242-243 in the passage set out above, Lord Diplock formulated what he said was the question in each case in terms specifically apt to broaden the effect of a claim by, in effect, treating as inessential strict compliance with the claim where there was a variant which would have no material effect upon the way in which the invention worked.
That is not the present case. Here what is sought is to narrow the area of claim 1 by redefining the result in terms of durability of the apparatus.
What was said by Lord Diplock did not, and does not appear to have been intended to, recast the well understood authorities which govern a case such as the present.
That this is how the matter has since been understood in England is illustrated by the following passage from the judgment of Neill LJ in C. Van der Lely NV v Ruston's Engineering Co. Ltd (1985) RPC 461 at 502-503:
"In construing the claims the court is entitled within certain limits to look at the specification as a whole in order to determine how the claims would be understood. In Rosedale Associated Manufacturers Ltd v Carlton Tyre Saving Co. Ltd (1960) RPC 59, Lord Evershed, M.R., used these words:
'. . . It is clearly . . . legitimate and appropriate in approaching the construction of claims to read the specification as a whole. Thereby the necessary background is obtained and in some cases the meaning of the words used in the claims may be affected or defined by what is said in the body of the specification.'
The body of the specification may therefore be referred to to ascertain the meaning of words and phrases used in the claims and for the purpose of resolving difficulties of construction occasioned by the claims when read by themselves. But
'if the claims have a plain meaning in themselves, then advantage cannot be taken of the language used in the body of the specification to make them mean something different' (per Lord Porter in Electrical and Musical Industries Ltd v Lissen Ltd
(1939) 56 RPC 23 at 39) Thus it is the function of the claim to define the monopoly which is claimed. It is therefore not legitimate, if the meaning of the claim when read by itself is plain, to diminish the ambit of the monopoly merely because in the body of the specification the patentee has described his invention in more restricted terms or by reference to some limitation which is not expressly or by proper inference reproduced in the claim itself."
In this Court, reliance was placed upon Catnic in dealing with an issue of infringement which arose in Allsop Inc. v Bintang Ltd (1989) 15 IPR 686. The Full Court (Bowen CJ, Beaumont and Burchett JJ), after setting out the significant passage from the speech of Lord Diplock, said (at 697):
"A variant which would inevitably have a material effect upon the way the invention worked is expressly excluded by his Lordship's formulation of the question."
Their Honours went on to refer to the requirement that a claim provide a workable standard suitable to the intended use and to the requirement of s. 40 of the 1952 Act that a claim be clear and succinct and define the invention.
In the present case, there has been no attack upon claim 1 which is based on s. 40. That is not surprising. The claim defines the invention but it does so in plain terms which do not include any further limitation as to the durability of the device.
We conclude that the claims of the Patent are bad for anticipation, being devices manufactured in accordance with the 602 drawing before the priority date of 14 January 1986. However, whilst the primary Judge, in our view, correctly so concluded, the proper basis for doing so differs from that found by his Honour.
The result is that the order as to revocation is upheld, and the appeal fails.
In light of the conclusion we have reached as to the proper construction of claim 1 and the anticipation by the 602 device, it is unnecessary to consider the point as to infringement taken in the notice of contention and whether it also should have been held that there was anticipation by publication of either or both the Festo drawing and the SMC devices.
The appeal should be dismissed. The appellant should pay the costs of the respondent.
6
7
0