Kauzal v Lee [1936] HCA 39; (1936) 58 CLR 670 (14 August 1936)

Appeal from the judgment of Long Innes J. restraining the appellant from infringing the respondent's letters patent 14463/28 "for improvements in drenchers for sheep and other stock."

Long before the respondent's invention, drenches or medicine had been forcibly administered to sheep and other stock by means of an ordinary drenching funnel. The object of the respondent's invention, according to his specification, was to provide a drencher whereby a predetermined quantity of drench might be administered under pressure by means of a hand-controlled plunger device in connection with a reservoir in which a thorough mixture of the liquid preparation was assured. The respondent described his invention in detail. I shall not go through that description. It is enough to say that evidence accepted by the learned trial judge established that the specification described no new mechanical method; that it described no element that was new, either structurally or functionally, unless in respect of a device for limiting the throw of the plunger by means of a stop pin or stud, illustrated in drawings attached to the specification. But it is conceded, or at all events is clear, that the elements of the invention described in the specification had never before been all brought together, and had never before been used in drenchers for sheep or other stock. The apparatus described works well, and is effective in use.

The respondent made six claims, but only two were relied upon at the hearing of the action, namely, the third and the fifth. Claim 3 was as follows:—"In drenchers for sheep and other stock of the kind described, a hand-controlled valve mechanism having a detachable barrel, a nozzle housing inlet and discharge valves, and provided with a nipple for connection to the reservoir, and a plunger in said barrel actuated by a trigger and adapted to draw a predetermined quantity of the drench into the barrel and force it therefrom through said nozzle." Now claim 3, it must be observed, limits the application of the invention to drenchers for sheep and other stock of the kind described in the specification (See Morris and Bastert v. Young[1]). But it is said that the claim is vague and ambiguous. Taken with the specification, a drencher of the kind described is one with a reservoir with a valve at the foot thereof connected by flexible or other tubing to a control valve mechanism adapted to draw the drench into a detachable barrel. The elements of the hand-controlled valve mechanism are then set forth. The main features of the mechanism are concisely stated in the claim, and are plain enough when read in conjunction with the specification of which they form part. But the words in claim 3, "and adapted to draw a predetermined quantity of the drench into the barrel and force it therefrom through said nozzle," occasion some difficulty. It is not important, I think, whether these words attach to "a hand-controlled valve mechanism" or to "a plunger in said barrel actuated by a trigger." But how is the mechanism or plunger adapted? And in what manner and by whom is the quantity of the drench predetermined? The specification itself contemplates barrels of different capacities in the mechanism. The specification and the claim rather point, I think, to the user determining the dose, and the specification contains and describes a mechanical contrivance whereby he can so predetermine it. The claim is not limited to that contrivance, but covers generally any means of adaptation for predetermining the dose. But that does not involve ambiguity or vagueness. An inventor is entitled to assume competence and ordinary skill in the person to whom the specification is addressed. And, given the methods suggested in the specification, any competent person would, I am satisfied, perceive and understand how adaptations to predetermine the dose might be made.

Claim 5 I shall deal with shortly. It is as follows:—"In drenchers for sheep and other stock of the kind described, a hand-controlled valve mechanism substantially as herein described and as illustrated in the accompanying drawings." This claim is limited to the particular mechanism illustrated in the drawings, and so limited, can, I think, be supported. But for this limitation, the claim would have been hopelessly bad, for there would have been no precise statement of the monopoly claimed.

It follows that claims 3 and 5, though without much originality, are not wanting in subject matter. Long Innes J. held that these claims had been infringed, and in this conclusion I agree and have nothing to add.

The appeal should be dismissed, subject, as was agreed, to a variation of the decree limiting the injunction to an infringement of claims 3 and 5.

The decree under appeal, although drawn up in general terms, establishes two only of the claims comprised in the patent put in suit. The claims relate to portion of an apparatus for dosing sheep with a drench, especially an oil drench. The apparatus consists of a tank or reservoir for the liquid slung on the shoulders of the operator, of a flexible tube leading to a pistol-shaped implement held in the hand and of that implement, which draws off the dose and ejects it through a nozzle into the sheep's mouth and down its gullet.

The need for such an apparatus arose not long before the patent was applied for. It was found that carbon-tetrachloride was a remedy both for fluke and for worms in sheep and paraffin oil proved a suitable vehicle for administering it. It was natural to look for some better and less wasteful means of drenching sheep with such a mixture than the funnel commonly used for water drenches.

The liquid is drawn from the flexible tube into the barrel of the pistol. The tube is fixed to a nipple leading to a valve in the nozzle. It is an inlet valve through which the dose is drawn. A plunger moves in the barrel and when it is pulled back it draws the liquid in through the valve which opens, that is to say, the atmospheric pressure forces the liquid into the barrel where otherwise a vacuum would be formed by the receding plunger. It is drawn back by a helical spring the resistance of which is overcome on the forward movement of the plunger by the pressure of the fingers on a lever corresponding in position to the trigger of a pistol. The upper part of the lever is attached by an arm to a rod which moves the plunger backwards and forwards in the barrel. The spring is fastened to the lever between its fulcrum and the arm and thus pulls the plunger back when the trigger is released. The forward movement of the plunger expels the charge or dose of liquid. It expels it through another valve in the nozzle, an outlet valve. The outlet valve opens with the pressure of the liquid and, of course, at the same time the inlet valve is kept closed. It is apparent that the amount of liquid thus administered must depend primarily upon the size of the barrel. But it also depends upon the distance to which the plunger retreats upon its backward movement. For the throw of the plunger determines how much of the chamber provided by the barrel is actually used for the intake of liquid. By means of a pin the extent to which the plunger may be drawn back can be limited and the dose thus diminished.

There is no difficulty in picking out the essential features of such an implement. It necessarily possesses separate orifices for the intake and expulsion of the liquid. For the chamber could not be automatically recharged from the reservoir through its outlet. The orifices must be sealed and opened in turn and are, therefore, provided with valves. The valves are both placed in the nozzle so that the chamber may be filled and emptied by the two opposite strokes of the plunger. The maximum dose is determined by the size of the barrel but, by checking the retreat of the plunger, it may be lessened to another definite amount.

An additional feature, which does not seem essential to its working, is given to the implement in the form adopted by the patentee. The barrel is made detachable. No doubt it is easier to clean if the barrel can be removed. But apparently the purpose of constructing the implement with a detachable barrel was to allow the use of barrels of different capacities.

The device contains no feature that is not in itself familiar. Its operation depends upon old principles. But nothing has been found anticipating the particular combination of elements which produces the implement and makes it effective. The search for anticipations seems to have been taken into every field where for some purpose or another devices for drawing liquid of any sort from a reservoir and expelling it might find a place. The citations not only relate to drenchers for administering liquids to animals but they range over things as diverse as hypodermic and surgical syringes, lubricating grease guns, fruit tree sprayers, paint sprayers, water pistols and even strange weapons for police use devised to throw chemical fluids or gases upon or over men or beasts in the hope of incapacitating, drugging or indelibly marking them. But not one of these devices, when examined, discloses the same means of attaining its purpose as the combination made by the patentee. Accordingly there appears to be nothing in the way of prior publication to destroy the validity of the patent.

The attack on its validity is put upon other and more substantial grounds. The specification and, in particular, the two claims on which the patentee now relies are said to be insufficient and avoidably ambiguous. It is denied, too, that the claims disclose any invention possessing subject matter.

The body of the specification states the object of the invention to be to devise a drencher whereby a predetermined quantity of the drench may be administered under pressure by means of a hand-controlled plunger device in communication with a reservoir in which a thorough mixture of the liquid preparation is assured. When the specification comes to the pistol-shaped hand piece, which it calls the control valve mechanism, it says that it is "preferably plunger-operated." But the specification gives no other means of operation. It then describes the invention by reference to detailed drawings, but again it speaks of the drawings as illustrations of "a preferred form" of drenching apparatus. The lever which, under pressure from the fingers, drives forward the plunger is called a trigger, a name which, although perhaps incorrectly used of what has no releasing action, nevertheless cannot be misunderstood if the drawings are examined. The description of the drawings includes an explanation of the manner in which the pin may intercept and limit the back stroke of the plunger. The principle employed is made clear enough, if to so simple a thing the word "principle" can be applied. But the exact way in which the pin is inserted is stated somewhat confusedly. We do not think obscurity upon such a detail could be fatal to the patent. For the invention does not depend upon the exact way in which the patentee would carry out this commonplace step, the mechanical nature of which is sufficiently indicated.

The first in order of the two surviving claims is the third in the specification. It is as follows:—"In drenchers for sheep and other stock of the kind described, a hand-controlled valve mechanism having a detachable barrel, a nozzle housing inlet and discharge valves, and provided with a nipple for connection to the reservoir, and a plunger in said barrel actuated by a trigger and adapted to draw a predetermined quantity of the drench into the barrel and force it therefrom through said nozzle."

This claim presents some difficulties because of the generality of the language used to describe each integer of the combination. It is important in considering its effect to notice the limiting operation of the introductory words, "in drenchers ... of the kind described." The reference is to a hand-operated drencher fed by a tube or pipe from a portable reservoir. The claim is restricted to an implement connected with such a tube. Moreover, the limitation explains the purpose of the nipple and of the inlet valve, afterwards mentioned in the claim. The integers in combination forming the "hand-controlled valve mechanism" are then enumerated. As we interpret the claim, it specifies eight features the combination of which forms the invention:—(a) the barrel is not fixed but removable; (b) its nozzle contains the inlet and the outlet; (c) these are valves; (d) the inlet has a nipple for connection with the reservoir; (e) there is a plunger in the barrel; (f) it is actuated by a lever used like a trigger; (g) the plunger is adapted to draw a predetermined quantity of liquid into the barrel; (h) it is adapted to force that quantity out through the nozzle.

In so stating the elements of the combination, we have attached grammatically to the word "plunger" the qualifying phrase "and adapted to draw a predetermined quantity of the drench into the barrel and force it therefrom through said nozzle." No doubt it is capable of qualifying the earlier expression "hand-controlled mechanism." But we think in both sense and form it is attached to the later word "plunger." It is the nearer noun. The conjunction "and" seems to couple the "actuated" and the "adapted." It is the plunger which forces the fluid through the nozzle. As appears from the description in the body of the specification and drawings, it is the plunger that draws in the drench. The whole phrase provides the chief ground for attacking the claim as insufficient and avoidably ambiguous. The construction we have given to the phrase in what we have said does not remove the main complaint against it. It deals only with one matter. But it is a matter which when resolved should be put on one side and no longer treated as tending to make the ambit of the monopoly uncertain. Vagueness of description, want of particularity and evident indistinctness of thought may be the source of so much uncertainty as to the scope of the monopoly that the claim fails to fulfil the requirement of stating with definiteness to what the patentee is exclusively entitled. In such a case the grammatical construction of the language may present no difficulty. Such indefiniteness has a deeper cause than an accident in the formal arrangement of a sentence which leaves it open to attribute an expression to either of two possible antecedents. When that happens a true question of construction arises. The language is open to two meanings. Each may be as definite as the other. The only doubt is which of the two was meant and the doubt springs from verbal order, position, or the like. In such a case, it is not likely that the scope of the claim would be so obscure as to disentitle the patentee to protection for what he meant to claim. But, in the present case, the imputation of ambiguity depends on more than a verbal equivocation. It is said that the claim does not state by whom or by what means the quantity of drench is predetermined, or how the plunger is adapted to draw the quantity. This criticism obtains its force from the generality of the language used in the phrase now in question. The specification gives two considerations upon which the size of the dose depends, viz., the size of the barrel and the stroke of the plunger. The size of the barrel and the stroke of the plunger may each be varied. It is obvious that the maker will decide the length to which the plunger may recede and the point where the pin to check it will be placed; he will decide what barrels he will supply. The user will decide which barrel and which stroke he will use.

The claim, instead of alluding to the size of the barrel and the travel of the plunger, covers the determination of the quantity by general words ascribing to the plunger a capacity to govern the matter. It is important to keep steadily in view the operation of such a qualification in the claim. It limits the ambit of the claim. Given a rival device containing every other feature stated in the claim, it would not amount to an infringement unless it could be said of the plunger that it was adapted to draw a predetermined quantity of the fluid. Now, so understood, the generality of the words used in the limitation means simply that the patentee is saying that his plunger does draw off a previously ascertained quantity, i.e., in the manner indicated in the specification, and he claims the combination of other features in conjunction with any plunger by which a previously ascertained quantity is drawn off, even although it is not done in the same manner as he has indicated.

The specification or claim cannot be accused of insufficiency. The patentee is not undertaking in the claim to describe a mode of predetermining the quantity. He has shown such a mode or modes. Nor is he undertaking to describe how the plunger may be controlled. This too he has done. Nor is there really any ambiguity. He states a general proposition. It is meant to be wide in one sense. But it is a limiting proposition. It requires that the quantity drawn off by the plunger should be predetermined. It is too obvious to need stating that the quantity must be settled by the capacity of the chamber when the plunger is drawn back to the full extent that is for the moment permitted to it. The claim seeks to avoid limiting the monopoly by confining it to one mechanical mode only of defining in advance the size of that chamber, or by allotting to the user and maker the parts to be played by them respectively in setting it. By failing to do this and so narrow the claim further, the patentee may have made his combination too wide. Its greater width has not in the event resulted in his encountering an anticipation. But, on the question of subject matter, it is, of course, true, in general, that the greater the number of limitations upon the area of a combination claim, the less danger there is to the patent.

The reference in the present claim to the plunger removes one difficulty arising from the body of the specification. It removes the uncertainty created by the use of the words "preferably" and "preferred" in referring to the apparatus illustrated in the drawings and describing it as "plunger-operated."

The question whether the claim discloses subject matter is the final and not least difficult of the matters upon which its validity depends. It is a combination the inventive merit of which can lie only in the exact association of features which leads to the achievement of its purpose. These eight features we have already enumerated. No doubt the utility of the implement depends upon them all. But its decisive characteristics seem to be the choice of the position of the valves and the use of a plunger moved by the trigger-like lever so that it would draw in and expel a fixed quantity of the drench. Because of the position of the valves, the plunger need not carry a valve itself, and yet can fulfil the double purpose by alternate strokes. The manual ease with which the implement may be operated depends on the trigger-like lever. Although the principles relied upon are old and simple and the features, separately considered, are used in daily practice for all sorts of purposes, the production of a new implement by their judicious use may involve an inventive step or display inventive ingenuity, if the integers are so combined and related that they work in co-operation to effect a purpose or provide an appliance which is new.

In the present case the appliance is a new one. The drenching of sheep is not a new purpose. But the use of oil drenches was a recent practice and former appliances do not seem to have been suitable. On the whole, we think that subject matter for an invention was involved in the patentee's mode of turning familiar principles to the purpose of producing a new drenching appliance and combining well-known elements in an arrangement resulting in the construction of an efficient automatic implement. There is more than one analogy to the present case in Higginson and Arundel v. Bentley and Bentley Ltd.[2]. Lord Sterndale said that no argument is required to show that the application of a well-known thing like a suction pump in a different manner and with a different object is not in itself subject matter of a patent. But he thought the idea was to make use of a pump to supply petrol to a carburettor, a thing not before successfully done, and for that purpose to make of the pump and other matters an apparatus which would produce the result. The main idea was in fact novel in the relevant connection, and was carried into effect by a particular combination devised for the purpose of known mechanical appliances, and the combination prima facie afforded subject matter.

The generality of the patentee's final limitation upon his monopoly does not appear to us to detract from the inventive steps which the combination involves.

The second of the two surviving claims is number five in the specification. It is as follows:—"In drenchers for sheep and other stock of the kind described, a hand-controlled valve mechanism substantially as herein described and as illustrated in the accompanying drawings."

We think this claim fails for ambiguity and vagueness. We are unable to ascertain from it what exactly is the combination of features claimed. If every substantial feature disclosed by the drawings goes to make up the invention claimed, perhaps a definite combination can be spelled out from them. But the words "as illustrated" seem to us to show that the drawings cannot be regarded as disclosing the only form of the invention. If the text of the specification is to be read as, so to speak, possessing equal or greater authority, then it seems to us that the indefiniteness arising from the use of the words "preferably" and "preferred" is fatal to the claim.

The third claim, however, is clearly infringed by the appellant's appliance and, in the view we take of the case, the fifth claim becomes immaterial. We think the decree should be amended to limit it to the third claim in the specification. Subject to this variation, the appeal should be dismissed with costs.

Subject to a variation in the decree appealed from, appeal dismissed with costs.

[1] (1895) 12 R.P.C. 455.

[2] (1922) 39 R.P.C., at pp. 186, 187.

High Court of Australia

Kauzal v Lee [1936] HCA 39; (1936) 58 CLR 670 (14 August 1936)

HIGH COURT OF AUSTRALIA